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  • richardmitnick 4:40 pm on October 14, 2021 Permalink | Reply
    Tags: "Department of Energy gives green light for a flagship petawatt laser facility at SLAC", , , , Laser Technology, Locating high-energy high-power lasers next to an XFEL can now be realized., , , Two state-of-the-art laser systems ­– a high-power petawatt laser and a high-energy kilojoule laser., University of Rochester’s Laboratory for Laser Energetics (LLE)   

    From DOE’s SLAC National Accelerator Laboratory (US) : “Department of Energy gives green light for a flagship petawatt laser facility at SLAC” 

    From DOE’s SLAC National Accelerator Laboratory (US)

    October 7, 2021
    Ali Sundermier
    Glennda Chui

    High-power lasers will work in concert with the lab’s X-ray laser to dramatically improve our understanding of matter in extreme conditions.

    Petawatt lasers are the most powerful on the planet, generating a million billion watts to produce some of the most extreme conditions seen on Earth. But today’s petawatt lasers are standalone facilities, with limited ability to fully diagnose the conditions they produce.

    A new facility at the Department of Energy’s SLAC National Accelerator Laboratory will change that. It will be the first to combine these powerful lasers with an X-ray free-electron laser (XFEL) that can probe the extreme conditions they create as never before. Coupled to the lab’s Linac Coherent Light Source (LCLS), the Matter in Extreme Conditions Upgrade, or MEC-U, promises to dramatically improve our understanding of the conditions needed to produce fusion energy and to replicate a wide range of astrophysical phenomena here on Earth.

    1
    In a new underground experimental facility coupled to SLAC’s Linac Coherent Light Source (LCLS), two state-of-the-art laser systems – a high-power petawatt laser and a high-energy kilojoule laser – will feed into two new experimental areas dedicated to the study of hot dense plasmas, astrophysics, and planetary science. (Gilliss Dyer/SLAC National Accelerator Laboratory)

    The project got approval from the DOE Office of Science (SC) on Monday to move from its conceptual design phase to preliminary design and execution, having passed what is known as Critical Decision 1.

    “It’s been gratifying to see the community rally together to support this project, and I think this achievement really validates those efforts. It shows that this notion of locating high-energy high-power lasers next to an XFEL can now be realized,” said SLAC scientist Arianna Gleason.

    “Working in concert, they’ll allow us to look behind the curtain of physics at extreme conditions to see how it’s all stitched together, opening a new frontier.”

    A national opportunity

    SLAC will work in partnership with The DOE’S Lawrence Livermore National Laboratory (US) and University of Rochester’s Laboratory for Laser Energetics (LLE) to design and construct the facility in a new underground cavern.

    University of Rochester(US) Laboratory for Laser Energetics.

    There, two state-of-the-art laser systems ­– a high-power petawatt laser and a high-energy kilojoule laser ­– will feed into two new experimental areas dedicated to the study of hot dense plasmas, astrophysics, and planetary science.

    “Not only are we working with some of the leading laser laboratories in the world, but we’re also working with world experts in experimental science, high energy density science and the operation of DOE Office of Science user facilities, where scientists from all over the world can come to do experiments,” said Alan Fry, MEC-U Project Director.

    Scientists started discussing what would be needed to make a quantum leap in this field in 2014 at a series of high-power laser workshops at SLAC. Three years later, a National Academies report called “Opportunities in intense ultrafast lasers: Reaching for the brightest light” highlighted the importance of this field of science. It recommended that DOE secure a key global advantage for the U.S. by locating high-intensity lasers “with existing infrastructure, such as particle accelerators.”

    Building on success

    This project builds on the success achieved at the existing Matter in Extreme Conditions (MEC) instrument at LCLS. Funded by DOE SC’s Fusion Energy Sciences program (FES), MEC uses short-pulse lasers coupled to X-ray laser pulses from LCLS to probe the characteristics of matter with unprecedented precision. These experiments have delivered a wealth of outstanding science and attracted worldwide media attention, with examples such as the study of “diamond rain” thought to exist on Neptune, to investigating the signatures of asteroid impacts on the Earth, to studying potential failure mechanisms of satellites due to solar flares.

    3
    The Matter in Extreme Conditions instrument at SLAC serves hundreds of scientists from across the community, providing the tools necessary to investigate extremely hot, dense matter similar to that found in the centers of stars and giant planets. Credit: Matt Beardsley/SLAC National Accelerator Laboratory.

    The existing MEC instrument is however limited in the regimes it can access. It has only modest laser capabilities which don’t allow it to reach the conditions of highest interest to researchers. The community called for investment into a petawatt laser that can produce unprecedented light pressures and generate plasmas at the even higher temperatures found in cosmic collisions, the cores of stars and planets, and fusion devices, giving scientists access to more extreme forms of matter needed to address the most important scientific challenges identified by the broad community of scientific users.

    “The new high-power lasers being designed by Livermore and Rochester are world-leading in their own right,” Fry said. “The fact that they’re coupled to LCLS then really puts it over the top in terms of capabilities.”

    MEC-U will also take advantage of the LCLS-II upgrade to the LCLS facility, which will provide X-ray laser beams of unsurpassed brilliance for probing those plasmas, doubling the X-ray energy that has been attainable to date.

    SLAC/LCLS II projected view.

    Magnets called undulators stretch roughly 100 meters down a tunnel at SLAC National Accelerator Laboratory, with one side (right) producing hard x-rays and the other soft x-rays.Credit: SLAC National Accelerator Laboratory.

    New scientific frontiers

    Access to the facility will be open to researchers from across the country and around the world, facilitated in part by LaserNetUS, a research network that is boosting access to high-intensity laser facilities at labs and universities across the country. This will allow more MEC users in a broader range of fields to use the facility, while also helping train new staff and develop new techniques.

    “This new facility will lead to a greater understanding of everything from fusion energy to the most extreme phenomena in the universe, shedding light on cosmic rays, planetary physics and stellar conditions.” said Siegfried Glenzer, director of the High Energy Density Division at SLAC. “It really shows the DOE’s dedication to continue to tackle the most important and exciting problems in plasma physics.”

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    SLAC National Accelerator Laboratory (US) originally named Stanford Linear Accelerator Center, is a Department of Energy (US) National Laboratory operated by Stanford University (US) under the programmatic direction of the Department of Energy (US) Office of Science and located in Menlo Park, California. It is the site of the Stanford Linear Accelerator, a 3.2 kilometer (2-mile) linear accelerator constructed in 1966 and shut down in the 2000s, which could accelerate electrons to energies of 50 GeV.
    Today SLAC research centers on a broad program in atomic and solid-state physics, chemistry, biology, and medicine using X-rays from synchrotron radiation and a free-electron laser as well as experimental and theoretical research in elementary particle physics, astroparticle physics, and cosmology.

    Founded in 1962 as the Stanford Linear Accelerator Center, the facility is located on 172 hectares (426 acres) of Stanford University-owned land on Sand Hill Road in Menlo Park, California—just west of the University’s main campus. The main accelerator is 3.2 kilometers (2 mi) long—the longest linear accelerator in the world—and has been operational since 1966.

    Research at SLAC has produced three Nobel Prizes in Physics

    1976: The charm quark—see J/ψ meson
    1990: Quark structure inside protons and neutrons
    1995: The tau lepton

    SLAC’s meeting facilities also provided a venue for the Homebrew Computer Club and other pioneers of the home computer revolution of the late 1970s and early 1980s.

    In 1984 the laboratory was named an ASME National Historic Engineering Landmark and an IEEE Milestone.

    SLAC developed and, in December 1991, began hosting the first World Wide Web server outside of Europe.

    In the early-to-mid 1990s, the Stanford Linear Collider (SLC) investigated the properties of the Z boson using the Stanford Large Detector.

    As of 2005, SLAC employed over 1,000 people, some 150 of whom were physicists with doctorate degrees, and served over 3,000 visiting researchers yearly, operating particle accelerators for high-energy physics and the Stanford Synchrotron Radiation Laboratory (SSRL) for synchrotron light radiation research, which was “indispensable” in the research leading to the 2006 Nobel Prize in Chemistry awarded to Stanford Professor Roger D. Kornberg.

    In October 2008, the Department of Energy announced that the center’s name would be changed to SLAC National Accelerator Laboratory. The reasons given include a better representation of the new direction of the lab and the ability to trademark the laboratory’s name. Stanford University had legally opposed the Department of Energy’s attempt to trademark “Stanford Linear Accelerator Center”.

    In March 2009, it was announced that the SLAC National Accelerator Laboratory was to receive $68.3 million in Recovery Act Funding to be disbursed by Department of Energy’s Office of Science.

    In October 2016, Bits and Watts launched as a collaboration between SLAC and Stanford University to design “better, greener electric grids”. SLAC later pulled out over concerns about an industry partner, the state-owned Chinese electric utility.

    Accelerator

    The main accelerator was an RF linear accelerator that accelerated electrons and positrons up to 50 GeV. At 3.2 km (2.0 mi) long, the accelerator was the longest linear accelerator in the world, and was claimed to be “the world’s most straight object.” until 2017 when the European x-ray free electron laser opened. The main accelerator is buried 9 m (30 ft) below ground and passes underneath Interstate Highway 280. The above-ground klystron gallery atop the beamline, was the longest building in the United States until the LIGO project’s twin interferometers were completed in 1999. It is easily distinguishable from the air and is marked as a visual waypoint on aeronautical charts.

    A portion of the original linear accelerator is now part of the Linac Coherent Light Source [below].

    Stanford Linear Collider

    The Stanford Linear Collider was a linear accelerator that collided electrons and positrons at SLAC. The center of mass energy was about 90 GeV, equal to the mass of the Z boson, which the accelerator was designed to study. Grad student Barrett D. Milliken discovered the first Z event on 12 April 1989 while poring over the previous day’s computer data from the Mark II detector. The bulk of the data was collected by the SLAC Large Detector, which came online in 1991. Although largely overshadowed by the Large Electron–Positron Collider at CERN, which began running in 1989, the highly polarized electron beam at SLC (close to 80%) made certain unique measurements possible, such as parity violation in Z Boson-b quark coupling.

    Presently no beam enters the south and north arcs in the machine, which leads to the Final Focus, therefore this section is mothballed to run beam into the PEP2 section from the beam switchyard.

    The SLAC Large Detector (SLD) was the main detector for the Stanford Linear Collider. It was designed primarily to detect Z bosons produced by the accelerator’s electron-positron collisions. Built in 1991, the SLD operated from 1992 to 1998.

    SLAC National Accelerator Laboratory(US)Large Detector

    PEP

    PEP (Positron-Electron Project) began operation in 1980, with center-of-mass energies up to 29 GeV. At its apex, PEP had five large particle detectors in operation, as well as a sixth smaller detector. About 300 researchers made used of PEP. PEP stopped operating in 1990, and PEP-II began construction in 1994.

    PEP-II

    From 1999 to 2008, the main purpose of the linear accelerator was to inject electrons and positrons into the PEP-II accelerator, an electron-positron collider with a pair of storage rings 2.2 km (1.4 mi) in circumference. PEP-II was host to the BaBar experiment, one of the so-called B-Factory experiments studying charge-parity symmetry.

    SLAC National Accelerator Laboratory(US) BaBar

    SLAC National Accelerator Laboratory(US)/SSRL

    Fermi Gamma-ray Space Telescope

    SLAC plays a primary role in the mission and operation of the Fermi Gamma-ray Space Telescope, launched in August 2008. The principal scientific objectives of this mission are:

    To understand the mechanisms of particle acceleration in AGNs, pulsars, and SNRs.
    To resolve the gamma-ray sky: unidentified sources and diffuse emission.
    To determine the high-energy behavior of gamma-ray bursts and transients.
    To probe dark matter and fundamental physics.


    KIPAC

    The Stanford PULSE Institute (PULSE) is a Stanford Independent Laboratory located in the Central Laboratory at SLAC. PULSE was created by Stanford in 2005 to help Stanford faculty and SLAC scientists develop ultrafast x-ray research at LCLS.

    The Linac Coherent Light Source (LCLS)[below] is a free electron laser facility located at SLAC. The LCLS is partially a reconstruction of the last 1/3 of the original linear accelerator at SLAC, and can deliver extremely intense x-ray radiation for research in a number of areas. It achieved first lasing in April 2009.

    The laser produces hard X-rays, 10^9 times the relative brightness of traditional synchrotron sources and is the most powerful x-ray source in the world. LCLS enables a variety of new experiments and provides enhancements for existing experimental methods. Often, x-rays are used to take “snapshots” of objects at the atomic level before obliterating samples. The laser’s wavelength, ranging from 6.2 to 0.13 nm (200 to 9500 electron volts (eV)) is similar to the width of an atom, providing extremely detailed information that was previously unattainable. Additionally, the laser is capable of capturing images with a “shutter speed” measured in femtoseconds, or million-billionths of a second, necessary because the intensity of the beam is often high enough so that the sample explodes on the femtosecond timescale.

    The LCLS-II [below] project is to provide a major upgrade to LCLS by adding two new X-ray laser beams. The new system will utilize the 500 m (1,600 ft) of existing tunnel to add a new superconducting accelerator at 4 GeV and two new sets of undulators that will increase the available energy range of LCLS. The advancement from the discoveries using this new capabilities may include new drugs, next-generation computers, and new materials.

    FACET

    In 2012, the first two-thirds (~2 km) of the original SLAC LINAC were recommissioned for a new user facility, the Facility for Advanced Accelerator Experimental Tests (FACET). This facility was capable of delivering 20 GeV, 3 nC electron (and positron) beams with short bunch lengths and small spot sizes, ideal for beam-driven plasma acceleration studies. The facility ended operations in 2016 for the constructions of LCLS-II which will occupy the first third of the SLAC LINAC. The FACET-II project will re-establish electron and positron beams in the middle third of the LINAC for the continuation of beam-driven plasma acceleration studies in 2019.

    The Next Linear Collider Test Accelerator (NLCTA) is a 60-120 MeV high-brightness electron beam linear accelerator used for experiments on advanced beam manipulation and acceleration techniques. It is located at SLAC’s end station B

    SSRL and LCLS are DOE Office of Science user facilities.

    Stanford University (US)

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members.

    Stanford University, officially Leland Stanford Junior University, is a private research university located in Stanford, California. Stanford was founded in 1885 by Leland and Jane Stanford in memory of their only child, Leland Stanford Jr., who had died of typhoid fever at age 15 the previous year. Stanford is consistently ranked as among the most prestigious and top universities in the world by major education publications. It is also one of the top fundraising institutions in the country, becoming the first school to raise more than a billion dollars in a year.

    Leland Stanford was a U.S. senator and former governor of California who made his fortune as a railroad tycoon. The school admitted its first students on October 1, 1891, as a coeducational and non-denominational institution. Stanford University struggled financially after the death of Leland Stanford in 1893 and again after much of the campus was damaged by the 1906 San Francisco earthquake. Following World War II, provost Frederick Terman supported faculty and graduates’ entrepreneurialism to build self-sufficient local industry in what would later be known as Silicon Valley.

    The university is organized around seven schools: three schools consisting of 40 academic departments at the undergraduate level as well as four professional schools that focus on graduate programs in law, medicine, education, and business. All schools are on the same campus. Students compete in 36 varsity sports, and the university is one of two private institutions in the Division I FBS Pac-12 Conference. It has gained 126 NCAA team championships, and Stanford has won the NACDA Directors’ Cup for 24 consecutive years, beginning in 1994–1995. In addition, Stanford students and alumni have won 270 Olympic medals including 139 gold medals.

    As of October 2020, 84 Nobel laureates, 28 Turing Award laureates, and eight Fields Medalists have been affiliated with Stanford as students, alumni, faculty, or staff. In addition, Stanford is particularly noted for its entrepreneurship and is one of the most successful universities in attracting funding for start-ups. Stanford alumni have founded numerous companies, which combined produce more than $2.7 trillion in annual revenue, roughly equivalent to the 7th largest economy in the world (as of 2020). Stanford is the alma mater of one president of the United States (Herbert Hoover), 74 living billionaires, and 17 astronauts. It is also one of the leading producers of Fulbright Scholars, Marshall Scholars, Rhodes Scholars, and members of the United States Congress.

    Stanford University was founded in 1885 by Leland and Jane Stanford, dedicated to Leland Stanford Jr, their only child. The institution opened in 1891 on Stanford’s previous Palo Alto farm.

    Jane and Leland Stanford modeled their university after the great eastern universities, most specifically Cornell University. Stanford opened being called the “Cornell of the West” in 1891 due to faculty being former Cornell affiliates (either professors, alumni, or both) including its first president, David Starr Jordan, and second president, John Casper Branner. Both Cornell and Stanford were among the first to have higher education be accessible, nonsectarian, and open to women as well as to men. Cornell is credited as one of the first American universities to adopt this radical departure from traditional education, and Stanford became an early adopter as well.

    Despite being impacted by earthquakes in both 1906 and 1989, the campus was rebuilt each time. In 1919, The Hoover Institution on War, Revolution and Peace was started by Herbert Hoover to preserve artifacts related to World War I. The Stanford Medical Center, completed in 1959, is a teaching hospital with over 800 beds. The DOE’s SLAC National Accelerator Laboratory(US)(originally named the Stanford Linear Accelerator Center), established in 1962, performs research in particle physics.

    Land

    Most of Stanford is on an 8,180-acre (12.8 sq mi; 33.1 km^2) campus, one of the largest in the United States. It is located on the San Francisco Peninsula, in the northwest part of the Santa Clara Valley (Silicon Valley) approximately 37 miles (60 km) southeast of San Francisco and approximately 20 miles (30 km) northwest of San Jose. In 2008, 60% of this land remained undeveloped.

    Stanford’s main campus includes a census-designated place within unincorporated Santa Clara County, although some of the university land (such as the Stanford Shopping Center and the Stanford Research Park) is within the city limits of Palo Alto. The campus also includes much land in unincorporated San Mateo County (including the SLAC National Accelerator Laboratory and the Jasper Ridge Biological Preserve), as well as in the city limits of Menlo Park (Stanford Hills neighborhood), Woodside, and Portola Valley.

    Non-central campus

    Stanford currently operates in various locations outside of its central campus.

    On the founding grant:

    Jasper Ridge Biological Preserve is a 1,200-acre (490 ha) natural reserve south of the central campus owned by the university and used by wildlife biologists for research.
    SLAC National Accelerator Laboratory is a facility west of the central campus operated by the university for the Department of Energy. It contains the longest linear particle accelerator in the world, 2 miles (3.2 km) on 426 acres (172 ha) of land.
    Golf course and a seasonal lake: The university also has its own golf course and a seasonal lake (Lake Lagunita, actually an irrigation reservoir), both home to the vulnerable California tiger salamander. As of 2012 Lake Lagunita was often dry and the university had no plans to artificially fill it.

    Off the founding grant:

    Hopkins Marine Station, in Pacific Grove, California, is a marine biology research center owned by the university since 1892.
    Study abroad locations: unlike typical study abroad programs, Stanford itself operates in several locations around the world; thus, each location has Stanford faculty-in-residence and staff in addition to students, creating a “mini-Stanford”.

    Redwood City campus for many of the university’s administrative offices located in Redwood City, California, a few miles north of the main campus. In 2005, the university purchased a small, 35-acre (14 ha) campus in Midpoint Technology Park intended for staff offices; development was delayed by The Great Recession. In 2015 the university announced a development plan and the Redwood City campus opened in March 2019.

    The Bass Center in Washington, DC provides a base, including housing, for the Stanford in Washington program for undergraduates. It includes a small art gallery open to the public.

    China: Stanford Center at Peking University, housed in the Lee Jung Sen Building, is a small center for researchers and students in collaboration with Beijing University [北京大学](CN) (Kavli Institute for Astronomy and Astrophysics at Peking University(CN) (KIAA-PKU).

    Administration and organization

    Stanford is a private, non-profit university that is administered as a corporate trust governed by a privately appointed board of trustees with a maximum membership of 38. Trustees serve five-year terms (not more than two consecutive terms) and meet five times annually.[83] A new trustee is chosen by the current trustees by ballot. The Stanford trustees also oversee the Stanford Research Park, the Stanford Shopping Center, the Cantor Center for Visual Arts, Stanford University Medical Center, and many associated medical facilities (including the Lucile Packard Children’s Hospital).

    The board appoints a president to serve as the chief executive officer of the university, to prescribe the duties of professors and course of study, to manage financial and business affairs, and to appoint nine vice presidents. The provost is the chief academic and budget officer, to whom the deans of each of the seven schools report. Persis Drell became the 13th provost in February 2017.

    As of 2018, the university was organized into seven academic schools. The schools of Humanities and Sciences (27 departments), Engineering (nine departments), and Earth, Energy & Environmental Sciences (four departments) have both graduate and undergraduate programs while the Schools of Law, Medicine, Education and Business have graduate programs only. The powers and authority of the faculty are vested in the Academic Council, which is made up of tenure and non-tenure line faculty, research faculty, senior fellows in some policy centers and institutes, the president of the university, and some other academic administrators, but most matters are handled by the Faculty Senate, made up of 55 elected representatives of the faculty.

    The Associated Students of Stanford University (ASSU) is the student government for Stanford and all registered students are members. Its elected leadership consists of the Undergraduate Senate elected by the undergraduate students, the Graduate Student Council elected by the graduate students, and the President and Vice President elected as a ticket by the entire student body.

    Stanford is the beneficiary of a special clause in the California Constitution, which explicitly exempts Stanford property from taxation so long as the property is used for educational purposes.

    Endowment and donations

    The university’s endowment, managed by the Stanford Management Company, was valued at $27.7 billion as of August 31, 2019. Payouts from the Stanford endowment covered approximately 21.8% of university expenses in the 2019 fiscal year. In the 2018 NACUBO-TIAA survey of colleges and universities in the United States and Canada, only Harvard University(US), the University of Texas System(US), and Yale University(US) had larger endowments than Stanford.

    In 2006, President John L. Hennessy launched a five-year campaign called the Stanford Challenge, which reached its $4.3 billion fundraising goal in 2009, two years ahead of time, but continued fundraising for the duration of the campaign. It concluded on December 31, 2011, having raised a total of $6.23 billion and breaking the previous campaign fundraising record of $3.88 billion held by Yale. Specifically, the campaign raised $253.7 million for undergraduate financial aid, as well as $2.33 billion for its initiative in “Seeking Solutions” to global problems, $1.61 billion for “Educating Leaders” by improving K-12 education, and $2.11 billion for “Foundation of Excellence” aimed at providing academic support for Stanford students and faculty. Funds supported 366 new fellowships for graduate students, 139 new endowed chairs for faculty, and 38 new or renovated buildings. The new funding also enabled the construction of a facility for stem cell research; a new campus for the business school; an expansion of the law school; a new Engineering Quad; a new art and art history building; an on-campus concert hall; a new art museum; and a planned expansion of the medical school, among other things. In 2012, the university raised $1.035 billion, becoming the first school to raise more than a billion dollars in a year.

    Research centers and institutes

    DOE’s SLAC National Accelerator Laboratory(US)
    Stanford Research Institute, a center of innovation to support economic development in the region.
    Hoover Institution, a conservative American public policy institution and research institution that promotes personal and economic liberty, free enterprise, and limited government.
    Hasso Plattner Institute of Design, a multidisciplinary design school in cooperation with the Hasso Plattner Institute of University of Potsdam [Universität Potsdam](DE) that integrates product design, engineering, and business management education).
    Martin Luther King Jr. Research and Education Institute, which grew out of and still contains the Martin Luther King Jr. Papers Project.
    John S. Knight Fellowship for Professional Journalists
    Center for Ocean Solutions
    Together with UC Berkeley(US) and UC San Francisco(US), Stanford is part of the Biohub, a new medical science research center founded in 2016 by a $600 million commitment from Facebook CEO and founder Mark Zuckerberg and pediatrician Priscilla Chan.

    Discoveries and innovation

    Natural sciences

    Biological synthesis of deoxyribonucleic acid (DNA) – Arthur Kornberg synthesized DNA material and won the Nobel Prize in Physiology or Medicine 1959 for his work at Stanford.
    First Transgenic organism – Stanley Cohen and Herbert Boyer were the first scientists to transplant genes from one living organism to another, a fundamental discovery for genetic engineering. Thousands of products have been developed on the basis of their work, including human growth hormone and hepatitis B vaccine.
    Laser – Arthur Leonard Schawlow shared the 1981 Nobel Prize in Physics with Nicolaas Bloembergen and Kai Siegbahn for his work on lasers.
    Nuclear magnetic resonance – Felix Bloch developed new methods for nuclear magnetic precision measurements, which are the underlying principles of the MRI.

    Computer and applied sciences

    ARPANETStanford Research Institute, formerly part of Stanford but on a separate campus, was the site of one of the four original ARPANET nodes.

    Internet—Stanford was the site where the original design of the Internet was undertaken. Vint Cerf led a research group to elaborate the design of the Transmission Control Protocol (TCP/IP) that he originally co-created with Robert E. Kahn (Bob Kahn) in 1973 and which formed the basis for the architecture of the Internet.

    Frequency modulation synthesis – John Chowning of the Music department invented the FM music synthesis algorithm in 1967, and Stanford later licensed it to Yamaha Corporation.

    Google – Google began in January 1996 as a research project by Larry Page and Sergey Brin when they were both PhD students at Stanford. They were working on the Stanford Digital Library Project (SDLP). The SDLP’s goal was “to develop the enabling technologies for a single, integrated and universal digital library” and it was funded through the National Science Foundation, among other federal agencies.

    Klystron tube – invented by the brothers Russell and Sigurd Varian at Stanford. Their prototype was completed and demonstrated successfully on August 30, 1937. Upon publication in 1939, news of the klystron immediately influenced the work of U.S. and UK researchers working on radar equipment.

    RISCARPA funded VLSI project of microprocessor design. Stanford and UC Berkeley are most associated with the popularization of this concept. The Stanford MIPS would go on to be commercialized as the successful MIPS architecture, while Berkeley RISC gave its name to the entire concept, commercialized as the SPARC. Another success from this era were IBM’s efforts that eventually led to the IBM POWER instruction set architecture, PowerPC, and Power ISA. As these projects matured, a wide variety of similar designs flourished in the late 1980s and especially the early 1990s, representing a major force in the Unix workstation market as well as embedded processors in laser printers, routers and similar products.
    SUN workstation – Andy Bechtolsheim designed the SUN workstation for the Stanford University Network communications project as a personal CAD workstation, which led to Sun Microsystems.

    Businesses and entrepreneurship

    Stanford is one of the most successful universities in creating companies and licensing its inventions to existing companies; it is often held up as a model for technology transfer. Stanford’s Office of Technology Licensing is responsible for commercializing university research, intellectual property, and university-developed projects.

    The university is described as having a strong venture culture in which students are encouraged, and often funded, to launch their own companies.

    Companies founded by Stanford alumni generate more than $2.7 trillion in annual revenue, equivalent to the 10th-largest economy in the world.

    Some companies closely associated with Stanford and their connections include:

    Hewlett-Packard, 1939, co-founders William R. Hewlett (B.S, PhD) and David Packard (M.S).
    Silicon Graphics, 1981, co-founders James H. Clark (Associate Professor) and several of his grad students.
    Sun Microsystems, 1982, co-founders Vinod Khosla (M.B.A), Andy Bechtolsheim (PhD) and Scott McNealy (M.B.A).
    Cisco, 1984, founders Leonard Bosack (M.S) and Sandy Lerner (M.S) who were in charge of Stanford Computer Science and Graduate School of Business computer operations groups respectively when the hardware was developed.[163]
    Yahoo!, 1994, co-founders Jerry Yang (B.S, M.S) and David Filo (M.S).
    Google, 1998, co-founders Larry Page (M.S) and Sergey Brin (M.S).
    LinkedIn, 2002, co-founders Reid Hoffman (B.S), Konstantin Guericke (B.S, M.S), Eric Lee (B.S), and Alan Liu (B.S).
    Instagram, 2010, co-founders Kevin Systrom (B.S) and Mike Krieger (B.S).
    Snapchat, 2011, co-founders Evan Spiegel and Bobby Murphy (B.S).
    Coursera, 2012, co-founders Andrew Ng (Associate Professor) and Daphne Koller (Professor, PhD).

    Student body

    Stanford enrolled 6,996 undergraduate and 10,253 graduate students as of the 2019–2020 school year. Women comprised 50.4% of undergraduates and 41.5% of graduate students. In the same academic year, the freshman retention rate was 99%.

    Stanford awarded 1,819 undergraduate degrees, 2,393 master’s degrees, 770 doctoral degrees, and 3270 professional degrees in the 2018–2019 school year. The four-year graduation rate for the class of 2017 cohort was 72.9%, and the six-year rate was 94.4%. The relatively low four-year graduation rate is a function of the university’s coterminal degree (or “coterm”) program, which allows students to earn a master’s degree as a 1-to-2-year extension of their undergraduate program.

    As of 2010, fifteen percent of undergraduates were first-generation students.

    Athletics

    As of 2016 Stanford had 16 male varsity sports and 20 female varsity sports, 19 club sports and about 27 intramural sports. In 1930, following a unanimous vote by the Executive Committee for the Associated Students, the athletic department adopted the mascot “Indian.” The Indian symbol and name were dropped by President Richard Lyman in 1972, after objections from Native American students and a vote by the student senate. The sports teams are now officially referred to as the “Stanford Cardinal,” referring to the deep red color, not the cardinal bird. Stanford is a member of the Pac-12 Conference in most sports, the Mountain Pacific Sports Federation in several other sports, and the America East Conference in field hockey with the participation in the inter-collegiate NCAA’s Division I FBS.

    Its traditional sports rival is the University of California, Berkeley, the neighbor to the north in the East Bay. The winner of the annual “Big Game” between the Cal and Cardinal football teams gains custody of the Stanford Axe.

    Stanford has had at least one NCAA team champion every year since the 1976–77 school year and has earned 126 NCAA national team titles since its establishment, the most among universities, and Stanford has won 522 individual national championships, the most by any university. Stanford has won the award for the top-ranked Division 1 athletic program—the NACDA Directors’ Cup, formerly known as the Sears Cup—annually for the past twenty-four straight years. Stanford athletes have won medals in every Olympic Games since 1912, winning 270 Olympic medals total, 139 of them gold. In the 2008 Summer Olympics, and 2016 Summer Olympics, Stanford won more Olympic medals than any other university in the United States. Stanford athletes won 16 medals at the 2012 Summer Olympics (12 gold, two silver and two bronze), and 27 medals at the 2016 Summer Olympics.

    Traditions

    The unofficial motto of Stanford, selected by President Jordan, is Die Luft der Freiheit weht. Translated from the German language, this quotation from Ulrich von Hutten means, “The wind of freedom blows.” The motto was controversial during World War I, when anything in German was suspect; at that time the university disavowed that this motto was official.
    Hail, Stanford, Hail! is the Stanford Hymn sometimes sung at ceremonies or adapted by the various University singing groups. It was written in 1892 by mechanical engineering professor Albert W. Smith and his wife, Mary Roberts Smith (in 1896 she earned the first Stanford doctorate in Economics and later became associate professor of Sociology), but was not officially adopted until after a performance on campus in March 1902 by the Mormon Tabernacle Choir.
    “Uncommon Man/Uncommon Woman”: Stanford does not award honorary degrees, but in 1953 the degree of “Uncommon Man/Uncommon Woman” was created to recognize individuals who give rare and extraordinary service to the University. Technically, this degree is awarded by the Stanford Associates, a voluntary group that is part of the university’s alumni association. As Stanford’s highest honor, it is not conferred at prescribed intervals, but only when appropriate to recognize extraordinary service. Recipients include Herbert Hoover, Bill Hewlett, Dave Packard, Lucile Packard, and John Gardner.
    Big Game events: The events in the week leading up to the Big Game vs. UC Berkeley, including Gaieties (a musical written, composed, produced, and performed by the students of Ram’s Head Theatrical Society).
    “Viennese Ball”: a formal ball with waltzes that was initially started in the 1970s by students returning from the now-closed Stanford in Vienna overseas program. It is now open to all students.
    “Full Moon on the Quad”: An annual event at Main Quad, where students gather to kiss one another starting at midnight. Typically organized by the Junior class cabinet, the festivities include live entertainment, such as music and dance performances.
    “Band Run”: An annual festivity at the beginning of the school year, where the band picks up freshmen from dorms across campus while stopping to perform at each location, culminating in a finale performance at Main Quad.
    “Mausoleum Party”: An annual Halloween Party at the Stanford Mausoleum, the final resting place of Leland Stanford Jr. and his parents. A 20-year tradition, the “Mausoleum Party” was on hiatus from 2002 to 2005 due to a lack of funding, but was revived in 2006. In 2008, it was hosted in Old Union rather than at the actual Mausoleum, because rain prohibited generators from being rented. In 2009, after fundraising efforts by the Junior Class Presidents and the ASSU Executive, the event was able to return to the Mausoleum despite facing budget cuts earlier in the year.
    Former campus traditions include the “Big Game bonfire” on Lake Lagunita (a seasonal lake usually dry in the fall), which was formally ended in 1997 because of the presence of endangered salamanders in the lake bed.

    Award laureates and scholars

    Stanford’s current community of scholars includes:

    19 Nobel Prize laureates (as of October 2020, 85 affiliates in total)
    171 members of the National Academy of Sciences
    109 members of National Academy of Engineering
    76 members of National Academy of Medicine
    288 members of the American Academy of Arts and Sciences
    19 recipients of the National Medal of Science
    1 recipient of the National Medal of Technology
    4 recipients of the National Humanities Medal
    49 members of American Philosophical Society
    56 fellows of the American Physics Society (since 1995)
    4 Pulitzer Prize winners
    31 MacArthur Fellows
    4 Wolf Foundation Prize winners
    2 ACL Lifetime Achievement Award winners
    14 AAAI fellows
    2 Presidential Medal of Freedom winners

    Stanford University Seal

     
  • richardmitnick 10:49 am on October 10, 2021 Permalink | Reply
    Tags: "Ruling Electrons and Vibrations in a Crystal with Polarized Light", , Atomic vibrations-and therefore phonons-can be generated in a solid by shining light on it., Laser Technology, , , , To the naked eye solids may appear perfectly still but in reality their constituent atoms and molecules are anything but.,   

    From Tokyo Institute of Technology [東京工業大学](JP): “Ruling Electrons and Vibrations in a Crystal with Polarized Light” 

    tokyo-tech-bloc

    From Tokyo Institute of Technology [東京工業大学](JP)

    October 8, 2021

    Associate Professor Kazutaka G. Nakamura
    Institute of Innovative Research,
    Tokyo Institute of Technology
    nakamura@msl.titech.ac.jp
    Tel +81-45-924-5387

    Contact
    Public Relations Division
    Tokyo Institute of Technology
    media@jim.titech.ac.jp
    Tel +81-3-5734-2975

    The quantum behavior of atomic vibrations excited in a crystal using light pulses has much to do with the polarization of the pulses, say materials scientists from Tokyo Tech. The findings from their latest study offer a new control parameter for the manipulation of coherently excited vibrations in solid materials at the quantum level.

    1

    To the naked eye solids may appear perfectly still but in reality their constituent atoms and molecules are anything but. They rotate and vibrate, respectively defining the so-called “rotational” and “vibrational” energy states of the system. As these atoms and molecules obey the rules of quantum physics, their rotation and vibration are, in fact, discretized, with a discrete “quantum” imagined as the smallest unit of such motion. For instance, the quantum of atomic vibration is a particle called “phonon.”

    Atomic vibrations-and therefore phonons-can be generated in a solid by shining light on it. A common way to do this is by using “ultrashort” light pulses (pulses that are tens to hundreds of femtoseconds long) to excite and manipulate phonons, a technique known as “coherent control.” While the phonons are usually controlled by changing the relative phase between consecutive optical pulses, studies have revealed that light polarization can also influence the behavior of these “optical phonons.”

    Dr. Kazutaka Nakamura’s team at Tokyo Institute of Technology (Tokyo Tech) explored the coherent control of longitudinal optical (LO) phonons (i.e., phonons corresponding to longitudinal vibrations excited by light) on the surface of a GaAs (gallium arsenide) single crystal and observed a “quantum interference” for both electrons and phonons for parallel polarization while only phonon interference for mutually perpendicular polarization. “We developed a quantum mechanical model with classical light fields for the coherent control of the LO phonon amplitude and applied this to GaAs and diamond crystals. However, we did not study the effects of polarization correlation between the light pulses in sufficient detail,” says Dr. Nakamura, Associate Professor at Tokyo Tech.

    Accordingly, his team focused on this aspect in a new study published in Physical Review B. They modeled the generation of LO phonons in GaAs with two relative phase-locked pulses using a simplified band model and “Raman scattering,” the phenomenon underlying the phonon generation, and calculated the phonon amplitudes for different polarization conditions.

    Their model predicted both electron and phonon interference for parallel-polarized pulses as expected, with no dependence on crystal orientation or the intensity ratio for allowed and forbidden Raman scattering. For perpendicularly polarized pulses, the model only predicted phonon interference at an angle of 45° from the [100] crystal direction. However, when one of the pulses was directed along [100], electron interference was excited by allowed Raman scattering.

    With such insights, the team looks forward to a better coherent control of optical phonons in crystals. “Our study demonstrates that polarization plays quite an important role in the excitation and detection of coherent phonons and would be especially relevant for materials with asymmetric interaction modes, such as bismuth, which has more than two optical phonon modes and electronic states. Our findings are thus extendable to other materials,” comments Nakamura.

    Indeed, light has its ways of getting both materials and material scientists excited!

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    tokyo-tech-campus

    Tokyo Institute of Technology [東京工業大学](JP) is the top national university for science and technology in Japan with a history spanning more than 130 years. Of the approximately 10,000 students at the Ookayama, Suzukakedai, and Tamachi Campuses, half are in their bachelor’s degree program while the other half are in master’s and doctoral degree programs. International students number 1,200. There are 1,200 faculty and 600 administrative and technical staff members.

    In the 21st century, the role of science and technology universities has become increasingly important. Tokyo Tech continues to develop global leaders in the fields of science and technology, and contributes to the betterment of society through its research, focusing on solutions to global issues. The Institute’s long-term goal is to become the world’s leading science and technology university.

     
  • richardmitnick 12:26 pm on October 6, 2021 Permalink | Reply
    Tags: "Lasers to Probe Origin of Life on a Frigid Moon and Take the Space-Time Pulse of Star-Shattering Collisions Built in Goddard Lab", , , European Space Agency’s (ESA) Laser Interferometer Space Antenna (LISA), Laser Technology, , NASA’s Dragonfly mission to Titan.   

    From NASA’s Goddard Space Flight Center (US) : “Lasers to Probe Origin of Life on a Frigid Moon and Take the Space-Time Pulse of Star-Shattering Collisions Built in Goddard Lab” 

    NASA Goddard Banner

    From NASA’s Goddard Space Flight Center (US)

    Oct 6, 2021

    William Steigerwald
    NASA Goddard Space Flight Center, Greenbelt, Maryland
    William.A.Steigerwald@nasa.gov

    On Saturn’s giant moon Titan, liquid methane and other hydrocarbons rain down, carving rivers, lakes and seas in a landscape of frozen water. The complex chemistry on this icy world could be analogous to the period when life first emerged on Earth, or it might yield an entirely new type of life. And even farther – light-years away in deep space, a black hole shreds the ultra-dense core of a dead star, warping the fabric of space itself and sending waves of space-time flying across the universe.

    At the Space Laser Assembly Cleanroom (SLAC) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the Laser and Electro-Optics Branch is building lasers for NASA’s Dragonfly mission to Titan and the European Space Agency’s (ESA) Laser Interferometer Space Antenna (LISA), which will measure waves in space-time caused by massive collisions.

    Goddard’s SLAC is a center of expertise for the art and science of building lasers for advanced instruments to explore exotic and extreme environments such as those investigated by Dragonfly and LISA.

    1
    This is the Dragonfly Mass Spectrometer (DraMS) Laser: THANOS (Throttled Hydrocarbon Analysis by Nanosecond Optical Source) engineering model. This laser is a NASA Goddard Code 554 in-house design that is currently being built and tested in the SLAC optical lab space. Credits:Matt Mullin/NASA.

    Lasers are difficult — they don’t “want” to work, says Barry Coyle, physicist at NASA Goddard.

    “Everything has to perfect,” Coyle said.

    That’s why assembling them in one place is so critical to efficiency — both in production and cost. This is the idea behind the SLAC, and it was conceived shortly after the launch of ICESat-1.

    ICESat-1 housed the Geoscience Laser Altimeter System, which was produced at a joint University of Maryland and Goddard facility. Although the laser worked well, Coyle said, producing space-flight laser systems outside of NASA could be expensive and inefficient.

    Coyle said he and others realized these expenses could be reduced if lasers were produced at an in-house laboratory. Additionally, time and energy could be saved.

    Pamela Millar, head of the Earth Science Technology Office, was the Remote Sensing branch head at the time and lead the effort to secure the funding for the SLAC, Coyle said. Ever since, the lab has been churning out lasers.

    Currently, the Goddard team is developing an ultraviolet (UV) laser in the SLAC — the Dragonfly Mass Spectrometer (DraMS) laser — for the Dragonfly mission. The mission involves a rotorcraft lander designed for multiple stops across the surface of Titan. The lander, being designed and built at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, will carry a full suite of instruments to sample materials and develop further knowledge of the moon’s surface composition and other properties.

    2
    This is the SLAC thermal vacuum chamber which is used to do environmental testing on space-flight class laser systems. The ICESAT-2 and GEDI lidar mission made use of this chamber for qualification and risk reduction testing. The flight and engineering model Dragonfly Mass Spectrometer (DraMS) Lasers as well as the engineering model LISA laser will be tested here next. Credit: Matt Mullin/NASA.

    Goddard laser engineer Matt Mullin is currently working on the DraMS laser, where his day-to-day work involves building or aligning hardware, building the laser, or running testing on subcomponents.

    “Basically, the UV laser beam will be focused down into a sample cup, which holds some of Titan’s surface materials. The beam will desorb molecular compounds from the sample and excite ions (atoms and molecules with a net electric charge) to be ingested into the mass spectrometer which the scientists can use to detect what that sample is comprised of,” he said.

    The laser is exciting because it is flying on a New Frontiers mission, Mullin said. The New Frontiers program is a NASA initiative that aims to fund missions that will explore parts of the solar system that are considered high priorities in planetary science.

    “We’ve sent a probe to Titan in the past, but this instrument and this mission is destined to solve a lot of the mysteries involved with this really interesting moon following on previous exploration,” Mullin said. “And to see if this moon could potentially harbor any form of life would be very interesting.”

    However, extremely cold temperatures and methane in Titan’s atmosphere and on its surface pose obstacles.

    “How do you get a laser there and how do you get it to work there?” Coyle said. “Those are the two challenges.”

    It is critical that the instrument is as small as possible and that the weight and energy consumption is minimized. On top of that, lasers need the perfect conditions to work properly.

    “You’re like balancing an egg on its end, it always wants to not work. You’re harnessing photons (particles of light) to do what you want — that’s very hard,” Coyle said.

    This is why the SLAC helps. Without SLAC, producing the laser would involve a lot of moving between buildings with separate teams working on it.

    “It helps having a central location where we can do the optics bonding, the cleaning assembly, all the infrastructure here — it’s great,” Coyle said.

    In addition to its work on Dragonfly, NASA-designed lasers, contributions to the ESA-led LISA mission, will be built in the lab. LISA will be the first space-based observatory of space-time waves, called gravitational waves. ESA looks to test Einstein’s theory of gravity by measuring gravitational waves in space generated by extremely violent events like black hole collisions.

    “The SLAC is a perfect place for us to build the LISA lasers,” Anthony Yu, the product development lead for the LISA laser, said. “The LISA lasers have many stringent requirements and we need to set up in-situ test stations to verify the laser performance during the build process. The SLAC allows us to set up specialized test stations for testing the laser real-time and also when it undergoes thermal vacuum cycling tests after it is assembled.”

    Paul Stysley, Goddard’s associate branch head of laser and electro-optics, and product development lead for the DraMS laser, said the heart and soul of SLAC is in the way it streamlines the technology development and production of lasers.

    “What makes the SLAC unique is having a centralized location to develop, build and test space-flight laser systems,” Stysley said. “A product flow and infrastructure are in place to develop, environmentally test and monitor a laser design from cradle to grave for a space-flight mission leading to significant reduction of technical risk and cost.”

    Mullin said working on Dragonfly and with the team has been amazing.

    “The real pleasure and the exciting part has been working with some of the best engineers and scientists in the world on this project,” Mullin said. “I remember watching the Discovery Channel about future exploration to outer moons like Europa or Titan, but I never really imagined that I’d be on one of the teams helping explore it.”

    See the full article here.


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    Please help promote STEM in your local schools.


    Stem Education Coalition


    NASA/Goddard Campus

    NASA’s Goddard Space Flight Center, Greenbelt, MD (US) is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    GSFC also operates two spaceflight tracking and data acquisition networks (the NASA Deep Space Network(US) and the Near Earth Network); develops and maintains advanced space and Earth science data information systems, and develops satellite systems for the National Oceanic and Atmospheric Administration(US) .

    GSFC manages operations for many NASA and international missions including the NASA/ESA Hubble Space Telescope; the Explorers Program; the Discovery Program; the Earth Observing System; INTEGRAL; MAVEN; OSIRIS-REx; the Solar and Heliospheric Observatory ; the Solar Dynamics Observatory; Tracking and Data Relay Satellite System ; Fermi; and Swift. Past missions managed by GSFC include the Rossi X-ray Timing Explorer (RXTE), Compton Gamma Ray Observatory, SMM, COBE, IUE, and ROSAT. Typically, unmanned Earth observation missions and observatories in Earth orbit are managed by GSFC, while unmanned planetary missions are managed by the Jet Propulsion Laboratory (JPL) in Pasadena, California(US).

    Goddard is one of four centers built by NASA since its founding on July 29, 1958. It is NASA’s first, and oldest, space center. Its original charter was to perform five major functions on behalf of NASA: technology development and fabrication; planning; scientific research; technical operations; and project management. The center is organized into several directorates, each charged with one of these key functions.

    Until May 1, 1959, NASA’s presence in Greenbelt, MD was known as the Beltsville Space Center. It was then renamed the Goddard Space Flight Center (GSFC), after Robert H. Goddard. Its first 157 employees transferred from the United States Navy’s Project Vanguard missile program, but continued their work at the Naval Research Laboratory in Washington, D.C., while the center was under construction.

    Goddard Space Flight Center contributed to Project Mercury, America’s first manned space flight program. The Center assumed a lead role for the project in its early days and managed the first 250 employees involved in the effort, who were stationed at Langley Research Center in Hampton, Virginia. However, the size and scope of Project Mercury soon prompted NASA to build a new Manned Spacecraft Center, now the Johnson Space Center, in Houston, Texas. Project Mercury’s personnel and activities were transferred there in 1961.

    The Goddard network tracked many early manned and unmanned spacecraft.

    Goddard Space Flight Center remained involved in the manned space flight program, providing computer support and radar tracking of flights through a worldwide network of ground stations called the Spacecraft Tracking and Data Acquisition Network (STDN). However, the Center focused primarily on designing unmanned satellites and spacecraft for scientific research missions. Goddard pioneered several fields of spacecraft development, including modular spacecraft design, which reduced costs and made it possible to repair satellites in orbit. Goddard’s Solar Max satellite, launched in 1980, was repaired by astronauts on the Space Shuttle Challenger in 1984. The Hubble Space Telescope, launched in 1990, remains in service and continues to grow in capability thanks to its modular design and multiple servicing missions by the Space Shuttle.

    Today, the center remains involved in each of NASA’s key programs. Goddard has developed more instruments for planetary exploration than any other organization, among them scientific instruments sent to every planet in the Solar System. The center’s contribution to the Earth Science Enterprise includes several spacecraft in the Earth Observing System fleet as well as EOSDIS, a science data collection, processing, and distribution system. For the manned space flight program, Goddard develops tools for use by astronauts during extra-vehicular activity, and operates the Lunar Reconnaissance Orbiter, a spacecraft designed to study the Moon in preparation for future manned exploration.

     
  • richardmitnick 5:38 pm on October 5, 2021 Permalink | Reply
    Tags: "Process leading to supernova explosions and cosmic radio bursts unearthed at PPPL", , , Laser Technology, Plasma-the hot charged state of matter composed of free electrons and atomic nuclei-makes up 99 percent of the visible universe., Quantum electrodynamic (QED) cascades   

    From DOE’s Princeton Plasma Physics Laboratory (US) : “Process leading to supernova explosions and cosmic radio bursts unearthed at PPPL” 

    From DOE’s Princeton Plasma Physics Laboratory (US)

    at

    Princeton University

    Princeton University (US)

    October 5, 2021
    John Greenwald

    1
    Physicist Kenan Qu with figures from his paper. Credit: Photo of Qu by Elle Starkman/PPPL Office of Communications. Collage by Kiran Sudarsanan.

    A promising method for producing and observing on Earth a process important to black holes, supernova explosions and other extreme cosmic events has been proposed by scientists at Princeton University (US)‘s Department of Astrophysical Sciences , DOE’s SLAC National Accelerator Laboratory (US), and the DOE’s Princeton Plasma Physics Laboratory (PPPL)(US). The process, called quantum electrodynamic (QED) cascades, can lead to supernovas—exploding stars—and fast radio bursts that equal in milliseconds the energy the sun puts out in three days.

    First demonstration

    The researchers produced the first theoretical demonstration that colliding a laboratory laser with a dense electron beam can produce high-density QED cascades. “We show that what was thought to be impossible is in fact possible,” said Kenan Qu, lead author of a paper in Physical Review Letters that describes the breakthrough demonstration. “That in turn suggests how previously unobserved collective effects can be probed with existing state-of-the-art laser and electron beam technologies.”

    The process unfolds in a straightforward manner. Colliding a strong laser pulse with a high energy electron beam splits a vacuum into high-density electron-positron pairs that begin to interact with one another. This interaction creates what are called collective plasma effects that influence how the pairs respond collectively to electrical or magnetic fields.

    Plasma-the hot charged state of matter composed of free electrons and atomic nuclei-makes up 99 percent of the visible universe. Plasma fuels fusion reactions that power the sun and stars, a process that PPPL and scientists around the world are seeking to develop on Earth. Plasma processes throughout the universe are strongly influenced by electromagnetic fields.

    The PRL paper focuses on the electromagnetic strength of the laser and the energy of the electron beam that the theory brings together to create QED cascades. “We seek to simulate the conditions that create electron-positron pairs with sufficient density that they produce measurable collective effects and see how to unambiguously verify these effects,” Qu said.

    The tasks called for uncovering the signature of successful plasma creation through a QED process. Researchers found the signature in the shift of a moderately intense laser to a higher frequency caused by the proposal to send the laser against an electron beam. “That finding solves the joint problem of producing the QED plasma regime most easily and observing it most easily,” Qu said. “The amount of the shift varies depending on the density of the plasma and the energy of the pairs.”

    Beyond current capabilities

    Theory previously showed that sufficiently strong lasers or electric or magnetic fields could create QED pairs. But the required magnitudes are so high as to be beyond current laboratory capabilities.

    However, “It turns out that current technology in lasers and relativistic beams [that travel near the speed of light], if co-located, is sufficient to access and observe this regime,” said physicist Nat Fisch, professor of astrophysical sciences and associate director for academic affairs at PPPL, and a co-author of the PRL paper and principal investigator of the project. “A key point is to use the laser to slow down the pairs so that their mass decreases, thereby boosting their contribution to the plasma frequency and making the collective plasma effects greater,” Fisch said. “Co-locating current technologies is vastly cheaper than building super-intense lasers,” he said.

    This work was funded by grants from the National Nuclear Security Administration and the Air Force Office of Scientific Research. Researchers now are gearing up to test the theoretical findings at SLAC at Stanford University, where a moderately strong laser is being developed and the source of electrons beams is already there. Physicist Sebastian Meuren, a co-author of the paper and a former post-doctoral visitor at PPPL who now is at SLAC, is centrally involved in this effort.

    “Like most fundamental physics this research is to satisfy our curiosity about the universe,” Qu said. “For the general community, one big impact is that we can save billions of dollars of tax revenue if the theory can be validated.”

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition


    PPPL campus

    Princeton Plasma Physics Laboratory (US) is a U.S. Department of Energy national laboratory managed by Princeton University. PPPL, on Princeton University’s Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit https://energy.gov/science.

    Princeton University

    Princeton University

    About Princeton: Overview

    Princeton University is a private Ivy League research university in Princeton, New Jersey(US). Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the nine colonial colleges chartered before the American Revolution. The institution moved to Newark in 1747, then to the current site nine years later. It was renamed Princeton University in 1896.

    Princeton provides undergraduate and graduate instruction in the humanities, social sciences, natural sciences, and engineering. It offers professional degrees through the Princeton School of Public and International Affairs, the School of Engineering and Applied Science, the School of Architecture and the Bendheim Center for Finance. The university also manages the DOE’s Princeton Plasma Physics Laboratory. Princeton has the largest endowment per student in the United States.

    As of October 2020, 69 Nobel laureates, 15 Fields Medalists and 14 Turing Award laureates have been affiliated with Princeton University as alumni, faculty members or researchers. In addition, Princeton has been associated with 21 National Medal of Science winners, 5 Abel Prize winners, 5 National Humanities Medal recipients, 215 Rhodes Scholars, 139 Gates Cambridge Scholars and 137 Marshall Scholars. Two U.S. Presidents, twelve U.S. Supreme Court Justices (three of whom currently serve on the court) and numerous living billionaires and foreign heads of state are all counted among Princeton’s alumni body. Princeton has also graduated many prominent members of the U.S. Congress and the U.S. Cabinet, including eight Secretaries of State, three Secretaries of Defense and the current Chairman of the Joint Chiefs of Staff.

    Princeton University, founded as the College of New Jersey, was considered the successor of the “Log College” founded by the Reverend William Tennent at Neshaminy, PA in about 1726. New Light Presbyterians founded the College of New Jersey in 1746 in Elizabeth, New Jersey. Its purpose was to train ministers. The college was the educational and religious capital of Scottish Presbyterian America. Unlike Harvard University(US), which was originally “intensely English” with graduates taking the side of the crown during the American Revolution, Princeton was founded to meet the religious needs of the period and many of its graduates took the American side in the war. In 1754, trustees of the College of New Jersey suggested that, in recognition of Governor Jonathan Belcher’s interest, Princeton should be named as Belcher College. Belcher replied: “What a name that would be!” In 1756, the college moved its campus to Princeton, New Jersey. Its home in Princeton was Nassau Hall, named for the royal House of Orange-Nassau of William III of England.

    Following the untimely deaths of Princeton’s first five presidents, John Witherspoon became president in 1768 and remained in that post until his death in 1794. During his presidency, Witherspoon shifted the college’s focus from training ministers to preparing a new generation for secular leadership in the new American nation. To this end, he tightened academic standards and solicited investment in the college. Witherspoon’s presidency constituted a long period of stability for the college, interrupted by the American Revolution and particularly the Battle of Princeton, during which British soldiers briefly occupied Nassau Hall; American forces, led by George Washington, fired cannon on the building to rout them from it.

    In 1812, the eighth president of the College of New Jersey, Ashbel Green (1812–23), helped establish the Princeton Theological Seminary next door. The plan to extend the theological curriculum met with “enthusiastic approval on the part of the authorities at the College of New Jersey.” Today, Princeton University and Princeton Theological Seminary maintain separate institutions with ties that include services such as cross-registration and mutual library access.

    Before the construction of Stanhope Hall in 1803, Nassau Hall was the college’s sole building. The cornerstone of the building was laid on September 17, 1754. During the summer of 1783, the Continental Congress met in Nassau Hall, making Princeton the country’s capital for four months. Over the centuries and through two redesigns following major fires (1802 and 1855), Nassau Hall’s role shifted from an all-purpose building, comprising office, dormitory, library, and classroom space; to classroom space exclusively; to its present role as the administrative center of the University. The class of 1879 donated twin lion sculptures that flanked the entrance until 1911, when that same class replaced them with tigers. Nassau Hall’s bell rang after the hall’s construction; however, the fire of 1802 melted it. The bell was then recast and melted again in the fire of 1855.

    James McCosh became the college’s president in 1868 and lifted the institution out of a low period that had been brought about by the American Civil War. During his two decades of service, he overhauled the curriculum, oversaw an expansion of inquiry into the sciences, and supervised the addition of a number of buildings in the High Victorian Gothic style to the campus. McCosh Hall is named in his honor.

    In 1879, the first thesis for a Doctor of Philosophy (Ph.D.) was submitted by James F. Williamson, Class of 1877.

    In 1896, the college officially changed its name from the College of New Jersey to Princeton University to honor the town in which it resides. During this year, the college also underwent large expansion and officially became a university. In 1900, the Graduate School was established.

    In 1902, Woodrow Wilson, graduate of the Class of 1879, was elected the 13th president of the university. Under Wilson, Princeton introduced the preceptorial system in 1905, a then-unique concept in the United States that augmented the standard lecture method of teaching with a more personal form in which small groups of students, or precepts, could interact with a single instructor, or preceptor, in their field of interest.

    In 1906, the reservoir Carnegie Lake was created by Andrew Carnegie. A collection of historical photographs of the building of the lake is housed at the Seeley G. Mudd Manuscript Library on Princeton’s campus. On October 2, 1913, the Princeton University Graduate College was dedicated. In 1919 the School of Architecture was established. In 1933, Albert Einstein became a lifetime member of the Institute for Advanced Study with an office on the Princeton campus. While always independent of the university, the Institute for Advanced Study occupied offices in Jones Hall for 6 years, from its opening in 1933, until its own campus was finished and opened in 1939.

    Coeducation

    In 1969, Princeton University first admitted women as undergraduates. In 1887, the university actually maintained and staffed a sister college, Evelyn College for Women, in the town of Princeton on Evelyn and Nassau streets. It was closed after roughly a decade of operation. After abortive discussions with Sarah Lawrence College to relocate the women’s college to Princeton and merge it with the University in 1967, the administration decided to admit women and turned to the issue of transforming the school’s operations and facilities into a female-friendly campus. The administration had barely finished these plans in April 1969 when the admissions office began mailing out its acceptance letters. Its five-year coeducation plan provided $7.8 million for the development of new facilities that would eventually house and educate 650 women students at Princeton by 1974. Ultimately, 148 women, consisting of 100 freshmen and transfer students of other years, entered Princeton on September 6, 1969 amidst much media attention. Princeton enrolled its first female graduate student, Sabra Follett Meservey, as a PhD candidate in Turkish history in 1961. A handful of undergraduate women had studied at Princeton from 1963 on, spending their junior year there to study “critical languages” in which Princeton’s offerings surpassed those of their home institutions. They were considered regular students for their year on campus, but were not candidates for a Princeton degree.

    As a result of a 1979 lawsuit by Sally Frank, Princeton’s eating clubs were required to go coeducational in 1991, after Tiger Inn’s appeal to the U.S. Supreme Court was denied. In 1987, the university changed the gendered lyrics of “Old Nassau” to reflect the school’s co-educational student body. From 2009 to 2011, Princeton professor Nannerl O. Keohane chaired a committee on undergraduate women’s leadership at the university, appointed by President Shirley M. Tilghman.

    The main campus sits on about 500 acres (2.0 km^2) in Princeton. In 2011, the main campus was named by Travel+Leisure as one of the most beautiful in the United States. The James Forrestal Campus is split between nearby Plainsboro and South Brunswick. The University also owns some property in West Windsor Township. The campuses are situated about one hour from both New York City and Philadelphia.

    The first building on campus was Nassau Hall, completed in 1756 and situated on the northern edge of campus facing Nassau Street. The campus expanded steadily around Nassau Hall during the early and middle 19th century. The McCosh presidency (1868–88) saw the construction of a number of buildings in the High Victorian Gothic and Romanesque Revival styles; many of them are now gone, leaving the remaining few to appear out of place. At the end of the 19th century much of Princeton’s architecture was designed by the Cope and Stewardson firm (same architects who designed a large part of Washington University in St Louis (US) and University of Pennsylvania(US)) resulting in the Collegiate Gothic style for which it is known today. Implemented initially by William Appleton Potter and later enforced by the University’s supervising architect, Ralph Adams Cram, the Collegiate Gothic style remained the standard for all new building on the Princeton campus through 1960. A flurry of construction in the 1960s produced a number of new buildings on the south side of the main campus, many of which have been poorly received. Several prominent architects have contributed some more recent additions, including Frank Gehry (Lewis Library), I. M. Pei (Spelman Halls), Demetri Porphyrios (Whitman College, a Collegiate Gothic project), Robert Venturi and Denise Scott Brown (Frist Campus Center, among several others), and Rafael Viñoly (Carl Icahn Laboratory).

    A group of 20th-century sculptures scattered throughout the campus forms the Putnam Collection of Sculpture. It includes works by Alexander Calder (Five Disks: One Empty), Jacob Epstein (Albert Einstein), Henry Moore (Oval with Points), Isamu Noguchi (White Sun), and Pablo Picasso (Head of a Woman). Richard Serra’s The Hedgehog and The Fox is located between Peyton and Fine halls next to Princeton Stadium and the Lewis Library.

    At the southern edge of the campus is Carnegie Lake, an artificial lake named for Andrew Carnegie. Carnegie financed the lake’s construction in 1906 at the behest of a friend who was a Princeton alumnus. Carnegie hoped the opportunity to take up rowing would inspire Princeton students to forsake football, which he considered “not gentlemanly.” The Shea Rowing Center on the lake’s shore continues to serve as the headquarters for Princeton rowing.

    Cannon Green

    Buried in the ground at the center of the lawn south of Nassau Hall is the “Big Cannon,” which was left in Princeton by British troops as they fled following the Battle of Princeton. It remained in Princeton until the War of 1812, when it was taken to New Brunswick. In 1836 the cannon was returned to Princeton and placed at the eastern end of town. It was removed to the campus under cover of night by Princeton students in 1838 and buried in its current location in 1840.

    A second “Little Cannon” is buried in the lawn in front of nearby Whig Hall. This cannon, which may also have been captured in the Battle of Princeton, was stolen by students of Rutgers University in 1875. The theft ignited the Rutgers-Princeton Cannon War. A compromise between the presidents of Princeton and Rutgers ended the war and forced the return of the Little Cannon to Princeton. The protruding cannons are occasionally painted scarlet by Rutgers students who continue the traditional dispute.

    In years when the Princeton football team beats the teams of both Harvard University and Yale University in the same season, Princeton celebrates with a bonfire on Cannon Green. This occurred in 2012, ending a five-year drought. The next bonfire happened on November 24, 2013, and was broadcast live over the Internet.

    Landscape

    Princeton’s grounds were designed by Beatrix Farrand between 1912 and 1943. Her contributions were most recently recognized with the naming of a courtyard for her. Subsequent changes to the landscape were introduced by Quennell Rothschild & Partners in 2000. In 2005, Michael Van Valkenburgh was hired as the new consulting landscape architect for the campus. Lynden B. Miller was invited to work with him as Princeton’s consulting gardening architect, focusing on the 17 gardens that are distributed throughout the campus.

    Buildings

    Nassau Hall

    Nassau Hall is the oldest building on campus. Begun in 1754 and completed in 1756, it was the first seat of the New Jersey Legislature in 1776, was involved in the battle of Princeton in 1777, and was the seat of the Congress of the Confederation (and thus capitol of the United States) from June 30, 1783, to November 4, 1783. It now houses the office of the university president and other administrative offices, and remains the symbolic center of the campus. The front entrance is flanked by two bronze tigers, a gift of the Princeton Class of 1879. Commencement is held on the front lawn of Nassau Hall in good weather. In 1966, Nassau Hall was added to the National Register of Historic Places.

    Residential colleges

    Princeton has six undergraduate residential colleges, each housing approximately 500 freshmen, sophomores, some juniors and seniors, and a handful of junior and senior resident advisers. Each college consists of a set of dormitories, a dining hall, a variety of other amenities—such as study spaces, libraries, performance spaces, and darkrooms—and a collection of administrators and associated faculty. Two colleges, First College and Forbes College (formerly Woodrow Wilson College and Princeton Inn College, respectively), date to the 1970s; three others, Rockefeller, Mathey, and Butler Colleges, were created in 1983 following the Committee on Undergraduate Residential Life (CURL) report, which suggested the institution of residential colleges as a solution to an allegedly fragmented campus social life. The construction of Whitman College, the university’s sixth residential college, was completed in 2007.

    Rockefeller and Mathey are located in the northwest corner of the campus; Princeton brochures often feature their Collegiate Gothic architecture. Like most of Princeton’s Gothic buildings, they predate the residential college system and were fashioned into colleges from individual dormitories.

    First and Butler, located south of the center of the campus, were built in the 1960s. First served as an early experiment in the establishment of the residential college system. Butler, like Rockefeller and Mathey, consisted of a collection of ordinary dorms (called the “New New Quad”) before the addition of a dining hall made it a residential college. Widely disliked for their edgy modernist design, including “waffle ceilings,” the dormitories on the Butler Quad were demolished in 2007. Butler is now reopened as a four-year residential college, housing both under- and upperclassmen.

    Forbes is located on the site of the historic Princeton Inn, a gracious hotel overlooking the Princeton golf course. The Princeton Inn, originally constructed in 1924, played regular host to important symposia and gatherings of renowned scholars from both the university and the nearby Institute for Advanced Study for many years. Forbes currently houses nearly 500 undergraduates in its residential halls.

    In 2003, Princeton broke ground for a sixth college named Whitman College after its principal sponsor, Meg Whitman, who graduated from Princeton in 1977. The new dormitories were constructed in the Collegiate Gothic architectural style and were designed by architect Demetri Porphyrios. Construction finished in 2007, and Whitman College was inaugurated as Princeton’s sixth residential college that same year.

    The precursor of the present college system in America was originally proposed by university president Woodrow Wilson in the early 20th century. For over 800 years, however, the collegiate system had already existed in Britain at Cambridge and Oxford Universities. Wilson’s model was much closer to Yale University (US)’s present system, which features four-year colleges. Lacking the support of the trustees, the plan languished until 1968. That year, Wilson College was established to cap a series of alternatives to the eating clubs. Fierce debates raged before the present residential college system emerged. The plan was first attempted at Yale, but the administration was initially uninterested; an exasperated alumnus, Edward Harkness, finally paid to have the college system implemented at Harvard in the 1920s, leading to the oft-quoted aphorism that the college system is a Princeton idea that was executed at Harvard with funding from Yale.

    Princeton has one graduate residential college, known simply as the Graduate College, located beyond Forbes College at the outskirts of campus. The far-flung location of the GC was the spoil of a squabble between Woodrow Wilson and then-Graduate School Dean Andrew Fleming West. Wilson preferred a central location for the college; West wanted the graduate students as far as possible from the campus. Ultimately, West prevailed. The Graduate College is composed of a large Collegiate Gothic section crowned by Cleveland Tower, a local landmark that also houses a world-class carillon. The attached New Graduate College provides a modern contrast in architectural style.

    McCarter Theatre

    The Tony-award-winning McCarter Theatre was built by the Princeton Triangle Club, a student performance group, using club profits and a gift from Princeton University alumnus Thomas McCarter. Today, the Triangle Club performs its annual freshmen revue, fall show, and Reunions performances in McCarter. McCarter is also recognized as one of the leading regional theaters in the United States.

    Art Museum

    The Princeton University Art Museum was established in 1882 to give students direct, intimate, and sustained access to original works of art that complement and enrich instruction and research at the university. This continues to be a primary function, along with serving as a community resource and a destination for national and international visitors.

    Numbering over 92,000 objects, the collections range from ancient to contemporary art and concentrate geographically on the Mediterranean regions, Western Europe, China, the United States, and Latin America. There is a collection of Greek and Roman antiquities, including ceramics, marbles, bronzes, and Roman mosaics from faculty excavations in Antioch. Medieval Europe is represented by sculpture, metalwork, and stained glass. The collection of Western European paintings includes examples from the early Renaissance through the 19th century, with masterpieces by Monet, Cézanne, and Van Gogh, and features a growing collection of 20th-century and contemporary art, including iconic paintings such as Andy Warhol’s Blue Marilyn.

    One of the best features of the museums is its collection of Chinese art, with important holdings in bronzes, tomb figurines, painting, and calligraphy. Its collection of pre-Columbian art includes examples of Mayan art, and is commonly considered to be the most important collection of pre-Columbian art outside of Latin America. The museum has collections of old master prints and drawings and a comprehensive collection of over 27,000 original photographs. African art and Northwest Coast Indian art are also represented. The Museum also oversees the outdoor Putnam Collection of Sculpture.

    University Chapel

    The Princeton University Chapel is located on the north side of campus, near Nassau Street. It was built between 1924 and 1928, at a cost of $2.3 million [approximately $34.2 million in 2020 dollars]. Ralph Adams Cram, the University’s supervising architect, designed the chapel, which he viewed as the crown jewel for the Collegiate Gothic motif he had championed for the campus. At the time of its construction, it was the second largest university chapel in the world, after King’s College Chapel, Cambridge. It underwent a two-year, $10 million restoration campaign between 2000 and 2002.

    Measured on the exterior, the chapel is 277 feet (84 m) long, 76 feet (23 m) wide at its transepts, and 121 feet (37 m) high. The exterior is Pennsylvania sandstone, with Indiana limestone used for the trim. The interior is mostly limestone and Aquia Creek sandstone. The design evokes an English church of the Middle Ages. The extensive iconography, in stained glass, stonework, and wood carvings, has the common theme of connecting religion and scholarship.

    The Chapel seats almost 2,000. It hosts weekly ecumenical Christian services, daily Roman Catholic mass, and several annual special events.

    Murray-Dodge Hall

    Murray-Dodge Hall houses the Office of Religious Life (ORL), the Murray Dodge Theater, the Murray-Dodge Café, the Muslim Prayer Room and the Interfaith Prayer Room. The ORL houses the office of the Dean of Religious Life, Alison Boden, and a number of university chaplains, including the country’s first Hindu chaplain, Vineet Chander; and one of the country’s first Muslim chaplains, Sohaib Sultan.

    Sustainability

    Published in 2008, Princeton’s Sustainability Plan highlights three priority areas for the University’s Office of Sustainability: reduction of greenhouse gas emissions; conservation of resources; and research, education, and civic engagement. Princeton has committed to reducing its carbon dioxide emissions to 1990 levels by 2020: Energy without the purchase of offsets. The University published its first Sustainability Progress Report in November 2009. The University has adopted a green purchasing policy and recycling program that focuses on paper products, construction materials, lightbulbs, furniture, and electronics. Its dining halls have set a goal to purchase 75% sustainable food products by 2015. The student organization “Greening Princeton” seeks to encourage the University administration to adopt environmentally friendly policies on campus.

    Organization

    The Trustees of Princeton University, a 40-member board, is responsible for the overall direction of the University. It approves the operating and capital budgets, supervises the investment of the University’s endowment and oversees campus real estate and long-range physical planning. The trustees also exercise prior review and approval concerning changes in major policies, such as those in instructional programs and admission, as well as tuition and fees and the hiring of faculty members.

    With an endowment of $26.1 billion, Princeton University is among the wealthiest universities in the world. Ranked in 2010 as the third largest endowment in the United States, the university had the greatest per-student endowment in the world (over $2 million for undergraduates) in 2011. Such a significant endowment is sustained through the continued donations of its alumni and is maintained by investment advisers. Some of Princeton’s wealth is invested in its art museum, which features works by Claude Monet, Vincent van Gogh, Jackson Pollock, and Andy Warhol among other prominent artists.

    Academics

    Undergraduates fulfill general education requirements, choose among a wide variety of elective courses, and pursue departmental concentrations and interdisciplinary certificate programs. Required independent work is a hallmark of undergraduate education at Princeton. Students graduate with either the Bachelor of Arts (A.B.) or the Bachelor of Science in Engineering (B.S.E.).

    The graduate school offers advanced degrees spanning the humanities, social sciences, natural sciences, and engineering. Doctoral education is available in most disciplines. It emphasizes original and independent scholarship whereas master’s degree programs in architecture, engineering, finance, and public affairs and public policy prepare candidates for careers in public life and professional practice.

    The university has ties with the Institute for Advanced Study, Princeton Theological Seminary and the Westminster Choir College of Rider University(US).

    Undergraduate

    Undergraduate courses in the humanities are traditionally either seminars or lectures held 2 or 3 times a week with an additional discussion seminar that is called a “precept.” To graduate, all A.B. candidates must complete a senior thesis and, in most departments, one or two extensive pieces of independent research that are known as “junior papers.” Juniors in some departments, including architecture and the creative arts, complete independent projects that differ from written research papers. A.B. candidates must also fulfill a three or four semester foreign language requirement and distribution requirements (which include, for example, classes in ethics, literature and the arts, and historical analysis) with a total of 31 classes. B.S.E. candidates follow a parallel track with an emphasis on a rigorous science and math curriculum, a computer science requirement, and at least two semesters of independent research including an optional senior thesis. All B.S.E. students must complete at least 36 classes. A.B. candidates typically have more freedom in course selection than B.S.E. candidates because of the fewer number of required classes. Nonetheless, in the spirit of a liberal arts education, both enjoy a comparatively high degree of latitude in creating a self-structured curriculum.

    Undergraduates agree to adhere to an academic integrity policy called the Honor Code, established in 1893. Under the Honor Code, faculty do not proctor examinations; instead, the students proctor one another and must report any suspected violation to an Honor Committee made up of undergraduates. The Committee investigates reported violations and holds a hearing if it is warranted. An acquittal at such a hearing results in the destruction of all records of the hearing; a conviction results in the student’s suspension or expulsion. The signed pledge required by the Honor Code is so integral to students’ academic experience that the Princeton Triangle Club performs a song about it each fall. Out-of-class exercises fall under the jurisdiction of the Faculty-Student Committee on Discipline. Undergraduates are expected to sign a pledge on their written work affirming that they have not plagiarized the work.

    Graduate

    The Graduate School has about 2,600 students in 42 academic departments and programs in social sciences; engineering; natural sciences; and humanities. These departments include the Department of Psychology; Department of History; and Department of Economics.

    In 2017–2018, it received nearly 11,000 applications for admission and accepted around 1,000 applicants. The University also awarded 319 Ph.D. degrees and 170 final master’s degrees. Princeton has no medical school, law school, business school, or school of education. (A short-lived Princeton Law School folded in 1852.) It offers professional graduate degrees in architecture; engineering; finance and public policy- the last through the Princeton School of Public and International Affairs founded in 1930 as the School of Public and International Affairs and renamed in 1948 after university president (and U.S. president) Woodrow Wilson, and most recently renamed in 2020.

    Libraries

    The Princeton University Library system houses over eleven million holdings including seven million bound volumes. The main university library, Firestone Library, which houses almost four million volumes, is one of the largest university libraries in the world. Additionally, it is among the largest “open stack” libraries in existence. Its collections include the autographed manuscript of F. Scott Fitzgerald’s The Great Gatsby and George F. Kennan’s Long Telegram. In addition to Firestone library, specialized libraries exist for architecture, art and archaeology, East Asian studies, engineering, music, public and international affairs, public policy and university archives, and the sciences. In an effort to expand access, these libraries also subscribe to thousands of electronic resources.

    Institutes

    High Meadows Environmental Institute

    The High Meadows Environmental Institute is an “interdisciplinary center of environmental research, education, and outreach” at the university. The institute was started in 1994. About 90 faculty members at Princeton University are affiliated with it.

    The High Meadows Environmental Institute has the following research centers:

    Carbon Mitigation Initiative (CMI): This is a 15-year-long partnership between PEI and British Petroleum with the goal of finding solutions to problems related to climate change. The Stabilization Wedge Game has been created as part of this initiative.
    Center for BioComplexity (CBC)
    Cooperative Institute for Climate Science (CICS): This is a collaboration with the National Oceanographic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory.
    Energy Systems Analysis Group
    Grand Challenges

     
  • richardmitnick 12:13 pm on October 1, 2021 Permalink | Reply
    Tags: "Extending the power of attosecond spectroscopy", , ATAS: attosecond transient absorption spectroscopy, Laser Technology, , The powerful transient absorption spectroscopy technique can unravel ultrafast motion of electrons and nuclei in a molecule in real time and with atomic spatial resolution.   

    From Swiss Federal Institute of Technology in Lausanne [EPFL-École Polytechnique Fédérale de Lausanne] (CH): “Extending the power of attosecond spectroscopy” 

    From Swiss Federal Institute of Technology in Lausanne [EPFL-École Polytechnique Fédérale de Lausanne] (CH)

    01.10.21
    Nik Papageorgiou

    1
    Scientists at EPFL have shown that the powerful transient absorption spectroscopy technique can unravel ultrafast motion of electrons and nuclei in a molecule in real time and with atomic spatial resolution.

    The last few decades have seen impressive progress in laser-based technologies, which have led to significant advancements in atomic and molecular physics. The development of ultrashort laser pulses now allows scientists to study extremely fast phenomena, like charge transport in molecules and elementary steps of chemical reactions. But beyond that, our ability to observe such processes on the attosecond scale (one quintillionth of a second) means that it is also possible to steer and probe the dynamics of individual electrons on their natural timeframes.

    One of the emerging ultrafast technologies is attosecond transient absorption spectroscopy (ATAS), which can track the movement of electrons at a specific site of a molecule. This is a particularly appealing feature of ATAS, because it permits tracing the evolution of the molecular system with spatial resolution at the atomic scale.

    Modern lasers can push chemistry into unexplored domains of light-matter interactions, where the role of theory in interpreting the results of ATAS measurements will be more important than ever before. But so far, the theory behind ATAS has been developed only for atoms or for molecules either in the absence of nuclear motion or in the absence of electronic coherence.

    Now, a team of physicists from EPFL’s Laboratory of Theoretical Physical Chemistry (LCPT) have extended ATAS theory to molecules, including a full account of the correlated electron-nuclear dynamics.

    The work, in collaboration with Alexander Kuleff at Ruprecht Karl University of Heidelberg [Ruprecht-Karls-Universität Heidelberg](DE), is published in Physical Review Letters.

    “We present a simple quasi-analytical expression for the absorption cross-section of molecules, which accounts for the nuclear motion and non-adiabatic dynamics and is composed from physically intuitive terms,” says Nikolay Golubev, a postdoc at LCPT and the study’s lead author.

    By extending ATAS theory, the scientists also show that this spectroscopy technique has sufficient resolution to “see” the follow-up decoherence of electron motion caused by the molecule’s nuclear rearrangement.

    Putting theory into practice, the team tested the polyatomic molecule propiolic acid as an example. “The simulation of X-ray ATAS of the propiolic acid was made possible by combining high-level ab initio electronic structure methods with efficient semiclassical nuclear dynamics,” says Jiří Vaníček, head of the LCPT. By advancing our knowledge of the correlated motion of electrons and nuclei in molecules, the findings of the LCPT researchers could also help our understanding of various other “attochemistry” phenomena.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    The Swiss Federal Institute of Technology in Lausanne [EPFL-École polytechnique fédérale de Lausanne] (CH) is a research institute and university in Lausanne, Switzerland, that specializes in natural sciences and engineering. It is one of the two Swiss Federal Institutes of Technology, and it has three main missions: education, research and technology transfer.

    The QS World University Rankings ranks EPFL(CH) 14th in the world across all fields in their 2020/2021 ranking, whereas Times Higher Education World University Rankings ranks EPFL(CH) as the world’s 19th best school for Engineering and Technology in 2020.

    EPFL(CH) is located in the French-speaking part of Switzerland; the sister institution in the German-speaking part of Switzerland is the Swiss Federal Institute of Technology ETH Zürich [Eidgenössische Technische Hochschule Zürich)](CH) . Associated with several specialized research institutes, the two universities form the Domain of the Swiss Federal Institutes of Technology (ETH Domain) [ETH-Bereich; Domaine des Écoles polytechniques fédérales] (CH) which is directly dependent on the Federal Department of Economic Affairs, Education and Research. In connection with research and teaching activities, EPFL(CH) operates a nuclear reactor CROCUS; a Tokamak Fusion reactor; a Blue Gene/Q Supercomputer; and P3 bio-hazard facilities.

    ETH Zürich, EPFL (Swiss Federal Institute of Technology in Lausanne) [École polytechnique fédérale de Lausanne](CH), and four associated research institutes form the Domain of the Swiss Federal Institutes of Technology (ETH Domain) [ETH-Bereich; Domaine des Écoles polytechniques fédérales] (CH) with the aim of collaborating on scientific projects.

    The roots of modern-day EPFL(CH) can be traced back to the foundation of a private school under the name École spéciale de Lausanne in 1853 at the initiative of Lois Rivier, a graduate of the École Centrale Paris (FR) and John Gay the then professor and rector of the Académie de Lausanne. At its inception it had only 11 students and the offices was located at Rue du Valentin in Lausanne. In 1869, it became the technical department of the public Académie de Lausanne. When the Académie was reorganised and acquired the status of a university in 1890, the technical faculty changed its name to École d’ingénieurs de l’Université de Lausanne. In 1946, it was renamed the École polytechnique de l’Université de Lausanne (EPUL). In 1969, the EPUL was separated from the rest of the University of Lausanne and became a federal institute under its current name. EPFL(CH), like ETH Zürich(CH), is thus directly controlled by the Swiss federal government. In contrast, all other universities in Switzerland are controlled by their respective cantonal governments. Following the nomination of Patrick Aebischer as president in 2000, EPFL(CH) has started to develop into the field of life sciences. It absorbed the Swiss Institute for Experimental Cancer Research (ISREC) in 2008.

    In 1946, there were 360 students. In 1969, EPFL(CH) had 1,400 students and 55 professors. In the past two decades the university has grown rapidly and as of 2012 roughly 14,000 people study or work on campus, about 9,300 of these being Bachelor, Master or PhD students. The environment at modern day EPFL(CH) is highly international with the school attracting students and researchers from all over the world. More than 125 countries are represented on the campus and the university has two official languages, French and English.

    Organization

    EPFL is organised into eight schools, themselves formed of institutes that group research units (laboratories or chairs) around common themes:

    School of Basic Sciences (SB, Jan S. Hesthaven)

    Institute of Mathematics (MATH, Victor Panaretos)
    Institute of Chemical Sciences and Engineering (ISIC, Emsley Lyndon)
    Institute of Physics (IPHYS, Harald Brune)
    European Centre of Atomic and Molecular Computations (CECAM, Ignacio Pagonabarraga Mora)
    Bernoulli Center (CIB, Nicolas Monod)
    Biomedical Imaging Research Center (CIBM, Rolf Gruetter)
    Interdisciplinary Center for Electron Microscopy (CIME, Cécile Hébert)
    Max Planck-EPFL Centre for Molecular Nanosciences and Technology (CMNT, Thomas Rizzo)
    Swiss Plasma Center (SPC, Ambrogio Fasoli)
    Laboratory of Astrophysics (LASTRO, Jean-Paul Kneib)

    School of Engineering (STI, Ali Sayed)

    Institute of Electrical Engineering (IEL, Giovanni De Micheli)
    Institute of Mechanical Engineering (IGM, Thomas Gmür)
    Institute of Materials (IMX, Michaud Véronique)
    Institute of Microengineering (IMT, Olivier Martin)
    Institute of Bioengineering (IBI, Matthias Lütolf)

    School of Architecture, Civil and Environmental Engineering (ENAC, Claudia R. Binder)

    Institute of Architecture (IA, Luca Ortelli)
    Civil Engineering Institute (IIC, Eugen Brühwiler)
    Institute of Urban and Regional Sciences (INTER, Philippe Thalmann)
    Environmental Engineering Institute (IIE, David Andrew Barry)

    School of Computer and Communication Sciences (IC, James Larus)

    Algorithms & Theoretical Computer Science
    Artificial Intelligence & Machine Learning
    Computational Biology
    Computer Architecture & Integrated Systems
    Data Management & Information Retrieval
    Graphics & Vision
    Human-Computer Interaction
    Information & Communication Theory
    Networking
    Programming Languages & Formal Methods
    Security & Cryptography
    Signal & Image Processing
    Systems

    School of Life Sciences (SV, Gisou van der Goot)

    Bachelor-Master Teaching Section in Life Sciences and Technologies (SSV)
    Brain Mind Institute (BMI, Carmen Sandi)
    Institute of Bioengineering (IBI, Melody Swartz)
    Swiss Institute for Experimental Cancer Research (ISREC, Douglas Hanahan)
    Global Health Institute (GHI, Bruno Lemaitre)
    Ten Technology Platforms & Core Facilities (PTECH)
    Center for Phenogenomics (CPG)
    NCCR Synaptic Bases of Mental Diseases (NCCR-SYNAPSY)

    College of Management of Technology (CDM)

    Swiss Finance Institute at EPFL (CDM-SFI, Damir Filipovic)
    Section of Management of Technology and Entrepreneurship (CDM-PMTE, Daniel Kuhn)
    Institute of Technology and Public Policy (CDM-ITPP, Matthias Finger)
    Institute of Management of Technology and Entrepreneurship (CDM-MTEI, Ralf Seifert)
    Section of Financial Engineering (CDM-IF, Julien Hugonnier)

    College of Humanities (CDH, Thomas David)

    Human and social sciences teaching program (CDH-SHS, Thomas David)

    EPFL Middle East (EME, Dr. Franco Vigliotti)[62]

    Section of Energy Management and Sustainability (MES, Prof. Maher Kayal)

    In addition to the eight schools there are seven closely related institutions

    Swiss Cancer Centre
    Center for Biomedical Imaging (CIBM)
    Centre for Advanced Modelling Science (CADMOS)
    École cantonale d’art de Lausanne (ECAL)
    Campus Biotech
    Wyss Center for Bio- and Neuro-engineering
    Swiss National Supercomputing Centre

     
  • richardmitnick 9:54 am on October 1, 2021 Permalink | Reply
    Tags: "A Highly Effective Laser Network the Size of a Grain of Sand", From topological insulators to topological lasers, Laser Technology, , , The Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg (DE), The long road to new topological lasers, The Technion – Israel Institute of Technology [ הטכניון – מכון טכנולוגי לישראל] (IL), VCSELs: Vertical-Cavity Surface-Emitting Lasers   

    From The Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg (DE) via SciTechDaily : “A Highly Effective Laser Network the Size of a Grain of Sand” 

    From The Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg (DE)

    via

    SciTechDaily

    1
    Artistic rendition of a topological array of vertically emitting lasers. All 30 microlasers along a topological interface (blue) act as one, collectively emitting coherent laser light (red). Credit: Pixelwg, Christian Kroneck.

    Tiny lasers acting together as one: Topological vertical cavity laser arrays

    Israeli and German researchers have developed a way to force an array of vertical cavity lasers to act together as a single laser — a highly effective laser network the size of a grain of sand. The findings are presented in a new joint research paper published online by the prestigious journal Science on September 24, 2021.

    Cell phones, car sensors, or data transmission in fiber optic networks are all using so called Vertical-Cavity Surface-Emitting Lasers (VCSELs) – semiconductor lasers that are firmly anchored in our everyday technology. Though widely used, the VCSEL device has a minuscule size of only a few microns, which sets a stringent limit on the output power it can generate.

    For years, scientists have sought to enhance the power emitted by such devices through combining many tiny VCSELs and forcing them to act as a single coherent laser, but had limited success. The current breakthrough uses a different scheme: it employs a unique geometrical arrangement of VCSELs on the chip that forces the flight to flow in a specific path – a photonic topological insulator platform.

    From topological insulators to topological lasers

    Topological insulators are revolutionary quantum materials that insulate on the inside but conduct electricity on their surface — without loss. Several years ago, The Technion – Israel Institute of Technology [ הטכניון – מכון טכנולוגי לישראל] (IL) group led by Prof. Mordechai Segev has introduced these innovative ideas into photonics, and demonstrated the first Photonic Topological Insulator, where light travels around the edges of a two-dimensional array of waveguides without being affected by defects or disorder. This opened a new field, now known as “Topological Photonics,” where hundreds of groups currently have active research.

    In 2018, the same group also found a way to use the properties of photonic topological insulators to force many micro-ring lasers to lock together and act as a single laser. But that system still had a major bottleneck: the light was circulating in the photonic chip confined to the same plane used for extracting the light out. That meant that the whole system was again subject to a power limit, imposed by the device used to get the light out, similar to having a single socket for a whole power plant. The current breakthrough uses a different scheme: the lasers are forced to lock within the planar chip, but the light is now emitted through the surface of the chip from each tiny laser and can be easily collected.

    Circumstances and participants

    This German-Israeli research project originated primarily during the Corona pandemic. Without the enormous commitment of the researchers involved, this scientific milestone would not have been possible. The research was conducted by PhD student Alex Dikopoltsev from the team of Distinguished Professor Mordechai Segev, of the Physics Department and the Electrical & Computer Engineering Department at the Technion – Israel Institute of Technology, and PhD student Tristan H. Harder from the team of Prof. Sebastian Klembt and Prof. Sven Höfling at the Chair of Applied Physics at the University of Würzburg, and the Cluster of Excellence ct.qmat — Complexity and Topology in Quantum Matter, in collaboration with researchers from Jena and Oldenburg. The device fabrication took advantage of the excellent clean room facilities at the University of Würzburg.

    The long road to new topological lasers

    “It is fascinating to see how science evolves,” said Prof. Segev of the Technion. “We went from fundamental physics concepts to foundational changes therein, and now to real technology that is now being pursued by companies. Back in 2015, when we started to work on topological insulator lasers, nobody believed it’s possible, because the topological concepts known at that time were limited to systems that do not, in fact – cannot — have gain. But all lasers require gain. So topological insulator lasers stood against everything known at that time. We were like a bunch of lunatics searching for something that was considered impossible. And now we have made a large step towards real technology that has many applications.”

    The Israeli and German team utilized the concepts of topological photonics with VCSELs that emit the light vertically, while the topological process responsible for the mutual coherence and locking of the VCSELs occurs in the plane of the chip. The end result is a powerful but very compact and efficient laser, not limited by a number of VCSEL emitters, and undisturbed by defects or altering temperatures.

    “The topological principle of this laser can generally work for all wavelengths and thus a range of materials,” explains German project leader Prof. Sebastian Klembt of the University of Würzburg, working on light-matter interaction and topological photonics within the ct.qmat Cluster of Excellence. “Exactly how many microlasers need to be arranged and connected would always depend entirely on the application. We can expand the size of the laser network to a very large size, and in principle it will remain coherent also for large numbers. It is great to see that topology, originally a branch of mathematics, has emerged as a revolutionary new toolbox for controlling, steering and improving laser properties.”

    The groundbreaking research has demonstrated that it is in fact theoretically and experimentally possible to combine VCSELs to achieve a more robust and highly efficient laser. As such, the results of the study pave the way towards applications of numerous future technologies such as medical devices, communications, and a variety of real-world applications.

    Science paper:
    Science

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Julius-Maximilians-Universität Würzburg campus

    The The Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg](DE) is a public research university in Würzburg, Germany. The university is one of the oldest institutions of higher learning in Germany, having been founded in 1402. The university initially had a brief run and was closed in 1415. It was reopened in 1582 on the initiative of Julius Echter von Mespelbrunn. Today, the university is named for Julius Echter von Mespelbrunn and Maximilian Joseph.

    The university is part of the U15 group of research-intensive German universities. The university is also a member of the Coimbra Group.

     
  • richardmitnick 7:59 pm on September 28, 2021 Permalink | Reply
    Tags: "Cracking Open Strong Field Quantum Electrodynamics", A petawatt is 1 times ten to the fifteenth power (that is followed by 15 zeroes) or a quadrillion watts., , , Laser Technology, Petawatt class lasers – juiced to even higher intensities via light-matter interactions – might provide a key to unlock the mysteries of the strong-field (SF) regime of quantum electrodynamics (QE, The output of today’s most powerful lasers is measured in petawatts.   

    From DOE’s Lawrence Berkeley National Laboratory (US) : “Cracking Open Strong Field Quantum Electrodynamics” 

    From DOE’s Lawrence Berkeley National Laboratory (US)

    September 28, 2021
    By William Schulz

    1
    The successive interaction of a high-power laser pulse (red and blue) with a plasma mirror (not shown) and a secondary target (translucent light grey) could create the conditions to probe Strong Field Quantum Electrodynamics effects that are far beyond current experimental capabilities. (Credit: Luca Fedeli/(CEA)[Alternative Energies and Atomic Energy Commission [Commissariat à l’énergie atomique et aux énergies alternatives](FR)).

    A newly published theoretical and computer modeling study suggests that the world’s most powerful lasers might finally crack the elusive physics behind some of the most extreme phenomena in the universe – gamma ray bursts, pulsar magnetospheres, and more.

    The international research team behind the study includes researchers from Lawrence Berkeley National Laboratory (Berkeley Lab) and France’s Alternative Energies and Atomic Energy Commission (CEA-LIDYL). They report their findings in the prestigious journal Physical Review Letters.

    The research team was led by CEA’s Alternative Energies and Atomic Energy Commission [Commissariat à l’énergie atomique et aux énergies alternatives](FR) Henri Vincenti, who proposed the main physical concept. Jean-Luc Vay and Andrew Myers, of Berkeley Lab’s Accelerator Technology and Applied Physics (ATAP) Division and Computational Research Division, respectively, led development of the simulation code used for the research. (Vincenti previously worked at Berkeley Lab as a Marie Curie Research Fellow and remains an ATAP affiliate and frequent collaborator.) The theoretical and numerical work was led by Luca Fedeli from Vincenti’s team at CEA.

    The team’s modeling study shows that petawatt (PW)-class lasers – juiced to even higher intensities via light-matter interactions – might provide a key to unlock the mysteries of the strong-field (SF) regime of quantum electrodynamics (QED). A petawatt is 1 times ten to the fifteenth power (that is, followed by 15 zeroes) or a quadrillion watts. The output of today’s most powerful lasers is measured in petawatts.

    “This is a powerful demonstration of how advanced simulation of complex systems can enable new paths for discovery science by integrating multiple physics processes – in this case, the laser interaction with a target and subsequent production of particles in a second target,” said ATAP Division Director Cameron Geddes.

    Lasers probe some of nature’s most jealously guarded secrets

    While QED is a cornerstone of modern physics that has withstood the rigor of experiment over many decades, probing SF-QED requires electromagnetic fields of an intensity many orders of magnitude beyond those normally available on Earth.

    Researchers have tried side routes to SF-QED, such as using powerful particle beams from accelerators to observe particle interactions with the strong fields that are naturally present in some aligned crystals.

    For a more direct approach, the highest electromagnetic fields available in a laboratory are delivered by PW-class lasers. A 10-PW laser (the world’s most powerful at this time), focused down to a few microns, can reach intensities close to 1023 watts per square centimeter. The associated electric field values can be as high as 1014 volts per meter. Yet studying SF-QED requires even higher field amplitudes than that – orders of magnitude beyond what can be achieved with those lasers.

    To break this barrier, researchers have planned to call on powerful electron beams, accessible at large accelerator or laser facilities. When a high-power laser pulse collides with a relativistic electron beam, the laser field amplitude seen by electrons in their rest frame can be increased by orders of magnitude, giving access to new SF-QED regimes.

    Though such methods are challenging experimentally, as they call for the synchronization in space and time of a high-power laser pulse and a relativistic electron beam at femtosecond and micron scales, a few such experiments have been successfully conducted, and several more are planned around the world at PW-class laser facilities.

    Using a moving, curved plasma mirror for a direct look

    The research team proposed a complementary method: a compact scheme that can directly boost the intensity of existing high-power laser beams. It is based on a well-known concept of light intensification and on their theoretical and computer modeling studies.

    The scheme consists of boosting the intensity of a PW laser pulse with a relativistic plasma mirror. Such a mirror can be formed when an ultrahigh intensity laser beam hits an optically polished solid target. Due to the high laser amplitude, the solid target is fully ionized, forming a dense plasma that reflects the incident light. At the same time the reflecting surface is actually moved by the intense laser field. As a result of that motion, part of the reflected laser pulse is temporally compressed and converted to a shorter wavelength by the Doppler effect.

    Radiation pressure from the laser gives this plasma mirror a natural curvature. This focuses the Doppler-boosted beam to much smaller spots, which can lead to extreme intensity gains – more than three orders of magnitude – where the Doppler-boosted laser beam is focused. The simulations indicate that a secondary target at this focus would give clear SF-QED signatures in actual experiments.

    3
    Left: In the proposed scheme for probing SF-QED with present-day or near-future lasers, a plasma mirror shaped by radiation pressure converts an intense laser pulse (red) into Doppler-boosted harmonics (purple) and focuses them on a secondary target, reaching extreme intensities. The dimensions involved are tens to hundreds of microns (millionths of a meter); the diameter of a human hair is a few to several tens of microns. (Credit: Luca Fedeli/CEA)

    Right: Berkeley Lab’s key contribution was leading the development of the simulation code used for the research. In this simulation image, the intense Doppler-boosted light pulses (red and blue) plow through the solid target (gray), generating high-energy photons (orange) that decay into pairs of electrons (green) and positrons (purple) after further interaction with the incoming light pulses. Only photons that have not yet decayed into pairs are shown. (Credit: Luca Fedeli/CEA)

    Berkeley Lab integral to international team-science effort

    The study drew upon Berkeley Lab’s diverse scientific resources, including its WarpX simulation code, which was developed for modeling advanced particle accelerators under the auspices of the U.S. Department of Energy’s Exascale Computing Project (US). The novel capabilities of WarpX allowed the modeling of the intensity boost and the interaction of the boosted pulse with the target. All previous simulation studies had only been able to explore proof-of-principle configurations.

    Experimental verification of the research team’s methodology for probing SF-QED might come from the BELLA: The Berkeley Lab Laser Accelerator (US), a petawatt-class laser with a repetition rate, unprecedented at that power, of a pulse per second.

    A view of BELLA, the Berkeley Lab Laser Accelerator. Credit: Roy Kaltschmidt-Berkeley Lab.

    Now under construction is a second beamline that might also contribute to experimental studies of SF-QED by Berkeley Lab researchers. A proposed new laser, kBELLA, could enable future high rate studies by bringing high intensity at a kilohertz repetition rate to the facility.

    The discovery via WarpX of novel high-intensity laser-plasma interaction regimes could have benefits far beyond ideas for exploring SF-QED. These include the better understanding and design of plasma-based accelerators such as those being developed at BELLA. More compact and less expensive than conventional accelerators of similar energy, they could eventually be game-changers in applications that range from extending the reach of high-energy physics and of penetrating photon sources for precision imaging, to implanting ions in semiconductors, treating cancer, developing new pharmaceuticals, and more.

    “It is gratifying to be able to contribute to the validation of new, potentially very impactful ideas via the use of our novel algorithms and codes,” Vay said of the Berkeley Lab team’s contributions to the study. “This is part of the beauty of collaborative team science.”

    This work was supported by the French National Research Agency (ANR) T-ERC program, the European Union’s Horizon 2020 research and innovation program, and the Cross-Disciplinary Program on Numerical Simulation of CEA, the French Alternative Energies and Atomic Energy Commission. Berkeley Lab’s participation was supported by the Exascale Computing Project, a collaborative effort of DOE’s Office of Science and National Nuclear Security Administration. The simulations were run on the Summit supercomputer at DOE’s Oak Ridge National Laboratory (US), using computer time awarded to “Plasma Mirrors ‘in Silico’: Extreme Intensity Light Sources and Compact Particle Accelerators” by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program.

    ORNL OLCF IBM AC922 SUMMIT supercomputer, was No.1 on the TOP500..

    See the full article here .

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    LBNL campus

    Bringing Science Solutions to the World

    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) (US) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the The National Academy of Sciences (US), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the The National Academy of Engineering (US), and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (US) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the University of California- Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a University of California-Berkeley (US) physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    History

    1931–1941

    The laboratory was founded on August 26, 1931, by Ernest Lawrence, as the Radiation Laboratory of the University of California, Berkeley, associated with the Physics Department. It centered physics research around his new instrument, the cyclotron, a type of particle accelerator for which he was awarded the Nobel Prize in Physics in 1939.

    LBNL 88 inch cyclotron.


    Throughout the 1930s, Lawrence pushed to create larger and larger machines for physics research, courting private philanthropists for funding. He was the first to develop a large team to build big projects to make discoveries in basic research. Eventually these machines grew too large to be held on the university grounds, and in 1940 the lab moved to its current site atop the hill above campus. Part of the team put together during this period includes two other young scientists who went on to establish large laboratories; J. Robert Oppenheimer founded DOE’s Los Alamos Laboratory (US), and Robert Wilson founded Fermi National Accelerator Laboratory(US).

    1942–1950

    Leslie Groves visited Lawrence’s Radiation Laboratory in late 1942 as he was organizing the Manhattan Project, meeting J. Robert Oppenheimer for the first time. Oppenheimer was tasked with organizing the nuclear bomb development effort and founded today’s Los Alamos National Laboratory to help keep the work secret. At the RadLab, Lawrence and his colleagues developed the technique of electromagnetic enrichment of uranium using their experience with cyclotrons. The “calutrons” (named after the University) became the basic unit of the massive Y-12 facility in Oak Ridge, Tennessee. Lawrence’s lab helped contribute to what have been judged to be the three most valuable technology developments of the war (the atomic bomb, proximity fuse, and radar). The cyclotron, whose construction was stalled during the war, was finished in November 1946. The Manhattan Project shut down two months later.

    1951–2018

    After the war, the Radiation Laboratory became one of the first laboratories to be incorporated into the Atomic Energy Commission (AEC) (now Department of Energy (US). The most highly classified work remained at Los Alamos, but the RadLab remained involved. Edward Teller suggested setting up a second lab similar to Los Alamos to compete with their designs. This led to the creation of an offshoot of the RadLab (now the Lawrence Livermore National Laboratory (US)) in 1952. Some of the RadLab’s work was transferred to the new lab, but some classified research continued at Berkeley Lab until the 1970s, when it became a laboratory dedicated only to unclassified scientific research.

    Shortly after the death of Lawrence in August 1958, the UC Radiation Laboratory (both branches) was renamed the Lawrence Radiation Laboratory. The Berkeley location became the Lawrence Berkeley Laboratory in 1971, although many continued to call it the RadLab. Gradually, another shortened form came into common usage, LBNL. Its formal name was amended to Ernest Orlando Lawrence Berkeley National Laboratory in 1995, when “National” was added to the names of all DOE labs. “Ernest Orlando” was later dropped to shorten the name. Today, the lab is commonly referred to as “Berkeley Lab”.

    The Alvarez Physics Memos are a set of informal working papers of the large group of physicists, engineers, computer programmers, and technicians led by Luis W. Alvarez from the early 1950s until his death in 1988. Over 1700 memos are available on-line, hosted by the Laboratory.

    The lab remains owned by the Department of Energy (US), with management from the University of California (US). Companies such as Intel were funding the lab’s research into computing chips.

    Science mission

    From the 1950s through the present, Berkeley Lab has maintained its status as a major international center for physics research, and has also diversified its research program into almost every realm of scientific investigation. Its mission is to solve the most pressing and profound scientific problems facing humanity, conduct basic research for a secure energy future, understand living systems to improve the environment, health, and energy supply, understand matter and energy in the universe, build and safely operate leading scientific facilities for the nation, and train the next generation of scientists and engineers.

    The Laboratory’s 20 scientific divisions are organized within six areas of research: Computing Sciences; Physical Sciences; Earth and Environmental Sciences; Biosciences; Energy Sciences; and Energy Technologies. Berkeley Lab has six main science thrusts: advancing integrated fundamental energy science; integrative biological and environmental system science; advanced computing for science impact; discovering the fundamental properties of matter and energy; accelerators for the future; and developing energy technology innovations for a sustainable future. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab tradition that continues today.

    Berkeley Lab operates five major National User Facilities for the DOE Office of Science (US):

    The Advanced Light Source (ALS) is a synchrotron light source with 41 beam lines providing ultraviolet, soft x-ray, and hard x-ray light to scientific experiments.

    LBNL/ALS


    The ALS is one of the world’s brightest sources of soft x-rays, which are used to characterize the electronic structure of matter and to reveal microscopic structures with elemental and chemical specificity. About 2,500 scientist-users carry out research at ALS every year. Berkeley Lab is proposing an upgrade of ALS which would increase the coherent flux of soft x-rays by two-three orders of magnitude.

    The DOE Joint Genome Institute (US) supports genomic research in support of the DOE missions in alternative energy, global carbon cycling, and environmental management. The JGI’s partner laboratories are Berkeley Lab, DOE’s Lawrence Livermore National Laboratory (US), DOE’s Oak Ridge National Laboratory (US)(ORNL), DOE’s Pacific Northwest National Laboratory (US) (PNNL), and the HudsonAlpha Institute for Biotechnology (US). The JGI’s central role is the development of a diversity of large-scale experimental and computational capabilities to link sequence to biological insights relevant to energy and environmental research. Approximately 1,200 scientist-users take advantage of JGI’s capabilities for their research every year.

    The LBNL Molecular Foundry (US) [above] is a multidisciplinary nanoscience research facility. Its seven research facilities focus on Imaging and Manipulation of Nanostructures; Nanofabrication; Theory of Nanostructured Materials; Inorganic Nanostructures; Biological Nanostructures; Organic and Macromolecular Synthesis; and Electron Microscopy. Approximately 700 scientist-users make use of these facilities in their research every year.

    The DOE’s NERSC National Energy Research Scientific Computing Center (US) is the scientific computing facility that provides large-scale computing for the DOE’s unclassified research programs. Its current systems provide over 3 billion computational hours annually. NERSC supports 6,000 scientific users from universities, national laboratories, and industry.

    DOE’s NERSC National Energy Research Scientific Computing Center(US) at Lawrence Berkeley National Laboratory

    The Genepool system is a cluster dedicated to the DOE Joint Genome Institute’s computing needs. Denovo is a smaller test system for Genepool that is primarily used by NERSC staff to test new system configurations and software.

    PDSF is a networked distributed computing cluster designed primarily to meet the detector simulation and data analysis requirements of physics, astrophysics and nuclear science collaborations.

    NERSC is a DOE Office of Science User Facility.

    The DOE’s Energy Science Network (US) is a high-speed network infrastructure optimized for very large scientific data flows. ESNet provides connectivity for all major DOE sites and facilities, and the network transports roughly 35 petabytes of traffic each month.

    Berkeley Lab is the lead partner in the DOE’s Joint Bioenergy Institute (US) (JBEI), located in Emeryville, California. Other partners are the DOE’s Sandia National Laboratory (US), the University of California (UC) campuses of Berkeley and Davis, the Carnegie Institution for Science (US), and DOE’s Lawrence Livermore National Laboratory (US) (LLNL). JBEI’s primary scientific mission is to advance the development of the next generation of biofuels – liquid fuels derived from the solar energy stored in plant biomass. JBEI is one of three new U.S. Department of Energy (DOE) Bioenergy Research Centers (BRCs).

    Berkeley Lab has a major role in two DOE Energy Innovation Hubs. The mission of the Joint Center for Artificial Photosynthesis (JCAP) is to find a cost-effective method to produce fuels using only sunlight, water, and carbon dioxide. The lead institution for JCAP is the California Institute of Technology (US) and Berkeley Lab is the second institutional center. The mission of the Joint Center for Energy Storage Research (JCESR) is to create next-generation battery technologies that will transform transportation and the electricity grid. DOE’s Argonne National Laboratory (US) leads JCESR and Berkeley Lab is a major partner.

     
  • richardmitnick 9:54 am on September 23, 2021 Permalink | Reply
    Tags: "Quantum cryptography Records with Higher-Dimensional Photons", , Laser Technology, , The laws of quantum physics guarantee that no third party can intercept quantum encrypted information., Using photons to transmit information.   

    From Technical University of Vienna [TU Wien-Technische Universität Wien] (AT) : “Quantum cryptography Records with Higher-Dimensional Photons” 

    From Technical University of Vienna [TU Wien-Technische Universität Wien] (AT)

    21. September 2021

    Prof. Marcus Huber
    Institute for Atomic and Subatomic Physics, IQOQI Vienna
    TU Wien
    +43 1 58801 141881
    marcus.huber@tuwien.ac.at

    A research team at TU Wien developed a new quantum transmission protocol that allows a higher data transmission rate and is much more robust against interference.

    1
    Marcus Huber

    2
    Experimental set up in China © Xiamin Hu

    Quantum cryptography is one of the most promising quantum technologies of our time: Exactly the same information is generated at two different locations, and the laws of quantum physics guarantee that no third party can intercept this information. This creates a code with which information can be perfectly encrypted.

    The team of Prof. Marcus Huber from the Atomic Institute of TU Wien developed a new type of quantum cryptography protocol, which has now been tested in practice in cooperation with Chinese research groups: While up to now one normally used photons that can be in two different states, the situation here is more complicated: Eight different paths can be taken by each of the photons. As the team has now been able to show, this makes the generation of the quantum cryptographic key faster and also significantly more robust against interference. The results have now been published in the scientific journal Physical Review Letters.

    Two states, two dimensions

    “There are many different ways of using photons to transmit information,” says Marcus Huber. “Often, experiments focus on their photons’ polarisation. For example, whether they oscillate horizontally or vertically – or whether they are in a quantum-mechanical superposition state in which, in a sense, they assume both states simultaneously. Similar to how you can describe a point on a two-dimensional plane with two coordinates, the state of the photon can be represented as a point in a two-dimensional space.”

    But a photon can also carry information independently of the direction of polarization. One can, for example, use the information about which path the photon is currently travelling on. This is exactly what has now been exploited: “A laser beam generates photon pairs in a special kind of crystal. There are eight different points in the crystal where this can happen,” explains Marcus Huber. Depending on the point at which the photon pair was created, each of the two photons can move along eight different paths – or along several paths at the same time, which is also permitted according to the laws of quantum theory.

    These two photons can be directed to completely different places and analysed there. One of the eight possibilities is measured, completely at random – but as the two photons are quantum-physically entangled, the same result is always obtained at both places. Whoever is standing at the first measuring device knows what another person is currently detecting at the second measuring device – and no one else in the universe can get hold of this information.

    Eight states, eight dimensions

    “The fact that we use eight possible paths here, and not two different polarisation directions as it is usually the case, makes a big difference,” says Marcus Huber. “The space of possible quantum states becomes much larger. The photon can no longer be described by a point in two dimensions, mathematically it now exists in eight dimensions.”

    This has several advantages: First, it allows more information to be generated: At 8307 bits per second and over 2.5 bits per photon pair, a new record has been set in entanglement-based quantum cryptography key generation. And secondly, it can be shown that this makes the process less susceptible to interference.

    “With all quantum technologies, you have to deal with the problem of decoherence,” says Marcus Huber. “No quantum system can be perfectly shielded from disturbances. But if it comes into contact with disturbances, then it can lose its quantum properties very easily: The quantum entanglements are destroyed.” Higher-dimensional quantum states, however, are less likely to lose their entanglement even in the presence of disturbances.

    Moreover, sophisticated quantum error-correction mechanisms can be used to compensate for the influence of external perturbations. “In the experiments, additional light was switched on in the laboratory to deliberately cause disturbances – and the protocol still worked,” says Marcus Huber. “But only if we actually used eight different paths. We were able to show that with a mere two-dimensional encoding a cryptographic key can no longer be generated in this case.”

    In principle, it should be possible to improve the new, faster and more reliable quantum cryptography protocol further by using additional degrees of freedom or an even larger number of different paths. “However, this not only increases the space of possible states, it also becomes increasingly difficult at some point to read out the states correctly,” says Marcus Huber. “We seem to have found a good compromise here, at least within the range of what is currently technically possible.”

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    At Technical University of Vienna [TU Wien-Technische Universität Wien] (AT) we have been conducting research, teaching and learning under the motto “Technology for people” for over 200 years. TU Wien has evolved into an open academic institution where discussions can happen, opinions can be voiced and arguments will be heard. Although everyone may have different individual philosophies and approaches to life, the staff, management personnel and students at TU Wien all promote open-mindedness and tolerance.

    Technical University of Vienna [TU Wien Technische Universität Wien] is one of the major universities in Vienna, Austria. The university has received extensive international and domestic recognition in teaching as well as in research, and it is a highly esteemed partner of innovation-oriented enterprises. It currently has about 28,100 students (29% women), eight faculties and about 5,000 staff members (3,800 academics).

    The university’s teaching and research is focused on engineering, computer science, and natural sciences. The university’s educational offerings have achieved wide international and domestic recognition.

    Research

    Development work in almost all areas of technology is encouraged by the interaction between basic research and the different fields of engineering sciences at TU Wien. Also, the framework of cooperative projects with other universities, research institutes and business sector partners is established by the research section of TU Wien. TU Wien has sharpened its research profile by defining competence fields and setting up interdisciplinary collaboration centres, and clearer outlines will be developed.

    Research focus points of TU Wien are introduced as computational science and engineering, quantum physics and quantum technologies, materials and matter, information and communication technology and energy and environment.

    The EU Research Support (EURS) provides services at TU Wien and informs both researchers and administrative staff in preparing and carrying out EU research projects.

     
  • richardmitnick 10:15 am on September 22, 2021 Permalink | Reply
    Tags: "Making Measurements With a Fine-Toothed Comb", , Laser Technology, ,   

    From National Institute of Standards and Technology (US) : “Making Measurements With a Fine-Toothed Comb” 

    From National Institute of Standards and Technology (US)

    September 22, 2021
    Rebecca Jacobson

    1
    Optical frequency combs allow scientists to measure light—and our world—with great precision and accuracy. This device has led to innovations that scientists never imagined when it was created. Credit: J. Wang/NIST.

    To many people, a measurement sounds mundane, like marking ticks on a ruler or reading the line on a thermometer. It’s a piece of data. And they tend to think that improved measurements look like finer and finer ticks on a ruler — which doesn’t seem very exciting.

    But making new measurements is more than just making finer marks on a ruler. To measure something is to understand it, pull it apart and see how it works. New measurements can unlock possibilities that even scientists never thought of when they started out.

    Perhaps there is no better example than the optical frequency comb. Very simply, this device is a ruler for light. Yet it’s so much more than a ruler.

    Radio waves, microwaves, visible light, X-rays and infrared are all part of a spectrum of electromagnetic frequencies. They’re all waves, traveling at the speed of light, but the distance between the peaks of those waves can be kilometers apart, like some radio waves, or nanometers apart, like visible light and ultraviolet.

    In the 1970s, scientists at the National Institute of Standards and Technology (NIST) were stuck. They wanted more precise and accurate atomic clocks, ones based on the very high optical frequencies of light released by atoms as their electrons jump between energy states, as opposed to the lower microwave frequencies they were using. Better clocks would give them a more precise definition of the second. A more precise second would give them a better definition of the meter, which is the distance light travels in a vacuum in a tiny fraction of a second. But all that relied on being able to measure these frequencies of light accurately and precisely.

    There was a gap in measurement between these two ends of the electromagnetic spectrum. Scientists could measure radio and microwave frequencies accurately, but there were no electronics that could count fast enough to keep up with the atom’s optical frequencies. They could use a laser with a matching frequency to read the atom’s optical frequency. Scientists had lasers with known, exact frequencies, but they could only produce a single frequency or color. Without knowing the exact frequency of the atom, finding the right frequency laser to read the atom would take a lot of trial and error. NIST scientists tried daisy-chaining several lasers of different frequencies together to make a rudimentary optical ruler. That worked well enough to redefine the meter but wasn’t a long-term solution.

    Enter the frequency comb, a Nobel Prize-winning device and the result of decades of research from NIST and others that you can read about here. The comb generates a billion pulses of light per second, which bounce back and forth inside an optical cavity. This creates millions of spikes of optical frequencies that look like rainbow-colored teeth on a comb (hence the name). The first tooth in that comb is set to a known frequency, which gives scientists a starting point to read the other frequencies. Much like a ruler, if you know the first marker is one millimeter and each marker is a millimeter apart, you can easily start measuring. Similarly, because they know exactly how far apart these frequencies are, scientists can translate these optical signals to microwaves with a simple mathematical formula, joining the two ends of the electromagnetic spectrum. This opens a lot of research doors.

    Scientists used this new technology to make better clocks, eventually developing clocks that are 100 times better than the cesium clocks used for civilian time standards. More accurate and precise clocks are critical for GPS navigation, which relies on precise time signals to determine your location. Better clocks also have research advantages, from detecting tiny changes in gravity to studying phenomena of the quantum world and perhaps finding dark matter. These clocks may eventually change how we define a second. But scientists couldn’t have predicted all the other ways the comb would be used.

    All atoms and molecules emit unique frequencies of light when they jump between energy states, not just the atoms used in clocks. If one of the frequencies from the comb hits an atom or molecule with the exact same frequency, scientists can identify what kind of atom or molecule they’ve hit. Using the optical frequency comb, scientists could study the composition of stars in exquisite detail. Astrophysicists can tell if they’ve found a new planet by measuring the changes in frequencies of the starlight as well. Using frequency combs, we can improve light-ranging systems, which bounce light off objects to detect them like radar or sonar. They can see objects through flames, helping NIST scientists study how structures fail during a fire.

    The comb is also being used to detect even the smallest amounts of greenhouse gases in the air or look for disease in human breath.

    All of that because we found a better way to measure light. Isn’t it amazing what a measurement can do?

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NIST Campus, Gaitherberg, MD, USA

    National Institute of Standards and Technology (US)‘s Mission, Vision, Core Competencies, and Core Values

    Mission

    To promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life.

    NIST’s vision

    NIST will be the world’s leader in creating critical measurement solutions and promoting equitable standards. Our efforts stimulate innovation, foster industrial competitiveness, and improve the quality of life.

    NIST’s core competencies

    Measurement science
    Rigorous traceability
    Development and use of standards

    NIST’s core values

    NIST is an organization with strong values, reflected both in our history and our current work. NIST leadership and staff will uphold these values to ensure a high performing environment that is safe and respectful of all.

    Perseverance: We take the long view, planning the future with scientific knowledge and imagination to ensure continued impact and relevance for our stakeholders.
    Integrity: We are ethical, honest, independent, and provide an objective perspective.
    Inclusivity: We work collaboratively to harness the diversity of people and ideas, both inside and outside of NIST, to attain the best solutions to multidisciplinary challenges.
    Excellence: We apply rigor and critical thinking to achieve world-class results and continuous improvement in everything we do.

    Background

    The Articles of Confederation, ratified by the colonies in 1781, contained the clause, “The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States”. Article 1, section 8, of the Constitution of the United States (1789), transferred this power to Congress; “The Congress shall have power…To coin money, regulate the value thereof, and of foreign coin, and fix the standard of weights and measures”.

    In January 1790, President George Washington, in his first annual message to Congress stated that, “Uniformity in the currency, weights, and measures of the United States is an object of great importance, and will, I am persuaded, be duly attended to”, and ordered Secretary of State Thomas Jefferson to prepare a plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States, afterwards referred to as the Jefferson report. On October 25, 1791, Washington appealed a third time to Congress, “A uniformity of the weights and measures of the country is among the important objects submitted to you by the Constitution and if it can be derived from a standard at once invariable and universal, must be no less honorable to the public council than conducive to the public convenience”, but it was not until 1838, that a uniform set of standards was worked out. In 1821, John Quincy Adams had declared “Weights and measures may be ranked among the necessities of life to every individual of human society”.

    From 1830 until 1901, the role of overseeing weights and measures was carried out by the Office of Standard Weights and Measures, which was part of the U.S. Coast and Geodetic Survey in the Department of the Treasury.

    Bureau of Standards

    In 1901 in response to a bill proposed by Congressman James H. Southard (R- Ohio) the National Bureau of Standards was founded with the mandate to provide standard weights and measures and to serve as the national physical laboratory for the United States. (Southard had previously sponsored a bill for metric conversion of the United States.)

    President Theodore Roosevelt appointed Samuel W. Stratton as the first director. The budget for the first year of operation was $40,000. The Bureau took custody of the copies of the kilogram and meter bars that were the standards for US measures, and set up a program to provide metrology services for United States scientific and commercial users. A laboratory site was constructed in Washington DC (US) and instruments were acquired from the national physical laboratories of Europe. In addition to weights and measures the Bureau developed instruments for electrical units and for measurement of light. In 1905 a meeting was called that would be the first National Conference on Weights and Measures.

    Initially conceived as purely a metrology agency the Bureau of Standards was directed by Herbert Hoover to set up divisions to develop commercial standards for materials and products. Some of these standards were for products intended for government use; but product standards also affected private-sector consumption. Quality standards were developed for products including some types of clothing; automobile brake systems and headlamps; antifreeze; and electrical safety. During World War I, the Bureau worked on multiple problems related to war production even operating its own facility to produce optical glass when European supplies were cut off. Between the wars Harry Diamond of the Bureau developed a blind approach radio aircraft landing system. During World War II military research and development was carried out including development of radio propagation forecast methods; the proximity fuze and the standardized airframe used originally for Project Pigeon; and shortly afterwards the autonomously radar-guided Bat anti-ship guided bomb and the Kingfisher family of torpedo-carrying missiles.

    In 1948, financed by the United States Air Force the Bureau began design and construction of SEAC: the Standards Eastern Automatic Computer. The computer went into operation in May 1950 using a combination of vacuum tubes and solid-state diode logic. About the same time the Standards Western Automatic Computer, was built at the Los Angeles office of the NBS by Harry Huskey and used for research there. A mobile version- DYSEAC- was built for the Signal Corps in 1954.

    Due to a changing mission, the “National Bureau of Standards” became the “National Institute of Standards and Technology (US)” in 1988.

    Following September 11, 2001, NIST conducted the official investigation into the collapse of the World Trade Center buildings.

    Organization

    NIST is headquartered in Gaithersburg, Maryland, and operates a facility in Boulder, Colorado, which was dedicated by President Eisenhower in 1954. NIST’s activities are organized into laboratory programs and extramural programs. Effective October 1, 2010, NIST was realigned by reducing the number of NIST laboratory units from ten to six. NIST Laboratories include:

    Communications Technology Laboratory (CTL)
    Engineering Laboratory (EL)
    Information Technology Laboratory (ITL)
    Center for Neutron Research (NCNR)
    Material Measurement Laboratory (MML)
    Physical Measurement Laboratory (PML)

    Extramural programs include:

    Hollings Manufacturing Extension Partnership (MEP), a nationwide network of centers to assist small and mid-sized manufacturers to create and retain jobs, improve efficiencies, and minimize waste through process improvements and to increase market penetration with innovation and growth strategies;
    Technology Innovation Program (TIP), a grant program where NIST and industry partners cost share the early-stage development of innovative but high-risk technologies;
    Baldrige Performance Excellence Program, which administers the Malcolm Baldrige National Quality Award, the nation’s highest award for performance and business excellence.

    NIST’s Boulder laboratories are best known for NIST‑F1 which houses an atomic clock. NIST‑F1 serves as the source of the nation’s official time. From its measurement of the natural resonance frequency of cesium—which defines the second—NIST broadcasts time signals via longwave radio station WWVB near Fort Collins in Colorado, and shortwave radio stations WWV and WWVH, located near Fort Collins and Kekaha in Hawai’i, respectively.

    NIST also operates a neutron science user facility: the NIST Center for Neutron Research (NCNR). The NCNR provides scientists access to a variety of neutron scattering instruments which they use in many research fields (materials science; fuel cells; biotechnology etc.).

    The SURF III Synchrotron Ultraviolet Radiation Facility is a source of synchrotron radiation in continuous operation since 1961. SURF III now serves as the US national standard for source-based radiometry throughout the generalized optical spectrum. All NASA-borne extreme-ultraviolet observation instruments have been calibrated at SURF since the 1970s, and SURF is used for measurement and characterization of systems for extreme ultraviolet lithography.

    The Center for Nanoscale Science and Technology (CNST) performs research in nanotechnology, both through internal research efforts and by running a user-accessible cleanroom nanomanufacturing facility. This “NanoFab” is equipped with tools for lithographic patterning and imaging (e.g., electron microscopes and atomic force microscopes).

    Committees

    NIST has seven standing committees:

    Technical Guidelines Development Committee (TGDC)
    Advisory Committee on Earthquake Hazards Reduction (ACEHR)
    National Construction Safety Team Advisory Committee (NCST Advisory Committee)
    Information Security and Privacy Advisory Board (ISPAB)
    Visiting Committee on Advanced Technology (VCAT)
    Board of Overseers for the Malcolm Baldrige National Quality Award (MBNQA Board of Overseers)
    Manufacturing Extension Partnership National Advisory Board (MEPNAB)

    Measurements and standards

    As part of its mission, NIST supplies industry, academia, government, and other users with over 1,300 Standard Reference Materials (SRMs). These artifacts are certified as having specific characteristics or component content, used as calibration standards for measuring equipment and procedures, quality control benchmarks for industrial processes, and experimental control samples.

    Handbook 44

    NIST publishes the Handbook 44 each year after the annual meeting of the National Conference on Weights and Measures (NCWM). Each edition is developed through cooperation of the Committee on Specifications and Tolerances of the NCWM and the Weights and Measures Division (WMD) of the NIST. The purpose of the book is a partial fulfillment of the statutory responsibility for “cooperation with the states in securing uniformity of weights and measures laws and methods of inspection”.

    NIST has been publishing various forms of what is now the Handbook 44 since 1918 and began publication under the current name in 1949. The 2010 edition conforms to the concept of the primary use of the SI (metric) measurements recommended by the Omnibus Foreign Trade and Competitiveness Act of 1988.

     
  • richardmitnick 2:06 pm on September 13, 2021 Permalink | Reply
    Tags: "New laser captures energy like noise-cancelling headphones", , , Extremely powerful microscopic lasers that are even smaller than the wavelength of the light they produce., Laser Technology, , , This technology uses laser light instead of electronics-an approach called photonics.   

    From Australian National University (AU) : “New laser captures energy like noise-cancelling headphones” 

    ANU Australian National University Bloc

    From Australian National University (AU)

    13 September 2021

    1
    Kirill Koshelev and Yuri Kivshar

    1
    Merging of BICs in the finite-size structure. a Calculated Hz field distribution at a = 573 nm in the finite-size domain with N = 15. N is the number of air holes along the vertical (or horizontal) direction. b Topological charge distributions in FT(Hz) at before-merging (left), pre-merging (middle), and merging (right). FT denotes the spatial Fourier transformation. The white circle of 7° indicates the first field minimum. c Schematic illustrations of the radiative loss in the three cases corresponding to b. d Calculated radiation factor, defined as |FT(Hz)/Q | , for a = 568, 573, 576, and 578 nm. The largest dark area is obtained at pre-merging of a = 573 nm. e The values of the inverse radiation factor plotted as a function of the lattice constant for N = 15 (black) and N = 21 (purple). The vertical red dashed line indicates the merging point in the infinite-size domain. f Radiative Q factor for N = 15 as a function of the lattice constant, calculated by the FDTD simulation. Credit: DOI: 10.1038/s41467-021-24502-0

    Physicists at The Australian National University (ANU) have developed extremely powerful microscopic lasers that are even smaller than the wavelength of the light they produce.

    So called ‘nanolasers’ have a huge variety of medical, surgical, industrial and military uses, covering everything from hair removal to laser printers and night-time surveillance.

    According to lead researcher Professor Yuri Kivshar, the nanolasers developed by his team promise to be even more powerful than existing lasers, allowing them to be useful in smaller-scale devices.

    “They can also be integrated on a chip,” he said.

    “For example, they can be mounted directly on the tip of an optical fibre to lighten or operate on a particular spot inside a human body.

    “This technology uses laser light instead of electronics-an approach called photonics. It’s exciting to see how this can be realised in everyday practical devices, like mobile phones.”

    Professor Kivshar’s team used a clever trick to modify conventional lasers, which traditionally comprise some form of light amplification device placed between two mirrors. As the light bounces back and forth between the two mirrors it becomes brighter and brighter.

    Instead of mirrors, the research team created a device that works like “inside-out” noise-cancelling headphones and which traps energy and prevents it from escaping. The trapped light energy builds up into a strong, well-shaped laser.

    This trick overcomes a well-known challenge of nanolasers — energy leakage.

    To fabricate the laser, the team collaborated with Professor Hong-Gyu Park and his group at Korea University [고려대학교](KR).

    The researchers say the device’s efficiency was high — only a small amount of energy was required to start the laser shining — with a threshold about 50 times lower than any previously reported nanolaser and narrow beam.

    Professor Kivshar said the new laser builds on a quantum mechanical discovery made almost 100 years ago.

    “This mathematical solution was published by Wigner and von Neumann in 1929, in a paper that seemed very strange at the time – it was not explained for many years,” Professor Kivshar said.

    “Now this 100-year-old discovery is driving tomorrow’s technology.”

    The research is reported in Nature Communications.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ANU Campus

    Australian National University (AU) is a world-leading university in Australia’s capital city, Canberra. Our location points to our unique history, ties to the Australian Government and special standing as a resource for the Australian people.

    Our focus on research as an asset, and an approach to education, ensures our graduates are in demand the world-over for their abilities to understand, and apply vision and creativity to addressing complex contemporary challenges.

    Australian National University is regarded as one of the world’s leading research universities, and is ranked as the number one university in Australia and the Southern Hemisphere by the 2021 QS World University Rankings. It is ranked 31st in the world by the 2021 QS World University Rankings, and 59th in the world (third in Australia) by the 2021 Times Higher Education.

    In the 2020 Times Higher Education Global Employability University Ranking, an annual ranking of university graduates’ employability, Australian National University was ranked 15th in the world (first in Australia). According to the 2020 QS World University by Subject, the university was also ranked among the top 10 in the world for Anthropology, Earth and Marine Sciences, Geography, Geology, Philosophy, Politics, and Sociology.

    Established in 1946, Australian National University is the only university to have been created by the Parliament of Australia. It traces its origins to Canberra University College, which was established in 1929 and was integrated into Australian National University in 1960. Australian National University enrolls 10,052 undergraduate and 10,840 postgraduate students and employs 3,753 staff. The university’s endowment stood at A$1.8 billion as of 2018.

    Australian National University counts six Nobel laureates and 49 Rhodes scholars among its faculty and alumni. The university has educated two prime ministers, 30 current Australian ambassadors and more than a dozen current heads of government departments of Australia. The latest releases of ANU’s scholarly publications are held through ANU Press online.

     
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