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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", , , , , Locating high-energy high-power lasers next to an XFEL can now be realized., , Particle Physics, 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 3:54 pm on October 14, 2021 Permalink | Reply
    Tags: "To Find Sterile Neutrinos Think Small", , , BeEST experimental program, , Particle Physics   

    From American Physical Society (US) : “To Find Sterile Neutrinos Think Small” 

    AmericanPhysicalSociety

    From American Physical Society (US)

    10.14.21

    Two small-scale experiments may beat the massive machines pursuing evidence of new physics—and could improve cancer treatment.

    Experiments have spotted anomalies hinting at a new type of neutrino, one that would go beyond the standard model of particle physics and perhaps open a portal to the dark sector. But no one has ever directly observed this hypothetical particle.

    1
    The BeEST experimental program, short for “Beryllium Electron-capture with Superconducting Tunnel junctions,” is utilizing complete momentum reconstruction of nuclear electron-capture decay in radioactive beryllium-7 atoms to search for these elusive new “ghost particles.” Credit: Spencer Fretwell, The Colorado School of Mines(US).

    Now a quantum dark matter detector and a proposed particle accelerator dreamt up by machine learning are poised to prove whether the sterile neutrino exists.

    The IsoDAR cyclotron would deliver ten times more beam current than any existing machine, according to the team at The Massachusetts Institute of Technology (US) that designed it.

    2
    A picture of the ion source used by the IsoDAR cyclotron team, which shows the ion beam glowing inside their device. Credit: IsoDAR collaboration.

    Taking up only a small underground footprint, the cyclotron may give definitive signs of sterile neutrinos within five years.

    At the same time, that intense beam could solve a major problem in cancer treatment: producing enough radioactive isotopes for killing cancerous cells and scanning tumors. The beam could produce high quantities of medical isotopes and even let hospitals and smaller laboratories make their own.

    “There is a direct connection between the technology that can be used to understand our universe, and the technology which can be used to save people’s lives,” said Loyd Waites, an MIT PhD candidate who will discuss the plans at the 2021 Fall Meeting of the APS Division of Nuclear Physics.

    Of the existing sterile neutrino hunters, one of the most powerful in the world possesses a single detector. The BeEST (pronounced “beast”) may sound like a behemoth, but the experiment uses one quantum sensor to measure nuclear recoils from the “kick” of a neutrino.

    This clean method searches for the mysterious particle without the added hurdle of looking for its interactions with normal matter. Just one month of testing yielded a new benchmark that covers a wide mass range—applicable to much bigger sterile neutrino experiments like “There is a direct connection between the technology that can be used to understand our universe, and the technology which can be used to save people’s lives,” said Loyd Waites, an MIT PhD candidate who will discuss the plans at the 2021 Fall Meeting of the APS Division of Nuclear Physics.

    Of the existing sterile neutrino hunters, one of the most powerful in the world possesses a single detector. The BeEST (pronounced “beast”) may sound like a behemoth, but the experiment uses one quantum sensor to measure nuclear recoils from the “kick” of a neutrino.

    This clean method searches for the mysterious particle without the added hurdle of looking for its interactions with normal matter. Just one month of testing yielded a new benchmark that covers a wide mass range—applicable to much bigger sterile neutrino experiments like KATRIN.

    KATRIN experiment aims to measure the mass of the neutrino using a huge device called a spectrometer (interior shown)KIT Karlsruhe Institute of Technology [Karlsruher Institut für Technologie] (DE)

    The KArlsruhe TRItium Neutrino KATRIN experiment which is presently being performed at Tritium Laboratory Karlsruhe at the KIT Karlsruhe Institute of Technology [Karlsruher Institut für Technologie] (DE) Campus North site will investigate the most important open issue in neutrino physics.

    “This initial work already excludes the existence of this type of sterile neutrino up to 10 times better than all previous decay experiments,” said Kyle Leach, an associate professor at the Colorado School of Mines, who presents the first round of results (recently reported in Physical Review Letters) at the meeting.

    The BeEST, a collaboration of 30 scientists from 10 institutions in North America and Europe, is also the first project to successfully use beryllium-7, regarded as the ideal atomic nucleus for the sterile neutrino hunt. Next up: scaling the BeEST setup to many more sensors, using new superconducting materials.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition
    American Physical Society US)
    Physicists are drowning in a flood of research papers in their own fields and coping with an even larger deluge in other areas of physics. How can an active researcher stay informed about the most important developments in physics? Physics highlights a selection of papers from the Physical Review journals. In consultation with expert scientists, the editors choose these papers for their importance and/or intrinsic interest. To highlight these papers, Physics features three kinds of articles: Viewpoints are commentaries written by active researchers, who are asked to explain the results to physicists in other subfields. Focus stories are written by professional science writers in a journalistic style and are intended to be accessible to students and non-experts. Synopses are brief editor-written summaries.

     
  • richardmitnick 3:23 pm on October 14, 2021 Permalink | Reply
    Tags: "Quarks and Antiquarks at High Momentum Shake the Foundations of Visible Matter", , , , , EMC effect: longstanding nuclear paradox, Particle Physics   

    From American Physical Society (US) : “Quarks and Antiquarks at High Momentum Shake the Foundations of Visible Matter” 

    AmericanPhysicalSociety

    From American Physical Society (US)

    10.14.21

    DOE’s Thomas Jefferson National Accelerator Facility (US) and DOE’s Fermi National Accelerator Laboratory (US) experiments present new results on nucleon structure

    Two independent studies have illuminated unexpected substructures in the fundamental components of all matter. Preliminary results using a novel tagging method could explain the origin of the longstanding nuclear paradox known as the EMC effect. Meanwhile, authors will share next steps after the recent observation of asymmetrical antimatter in the proton [Nature].

    1
    Artistic rendering of quarks in deuterium. Credit: Ran Shneor.

    Both groups will discuss their experiments at DOE’s Thomas Jefferson National Accelerator Facility and Fermilab during the 2021 Fall Meeting of the APS Division of Nuclear Physics. They will present the results and take questions from the press at a live virtual news briefing on October 12 at 2:15 p.m. EDT.

    One study presents new evidence on the EMC effect, identified nearly 40 years ago when researchers at European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN] discovered something surprising: Protons and neutrons bound in an atomic nucleus can change their internal makeup of quarks and gluons. But why such modifications arise, and how to predict them, remains unknown.

    For the first time, scientists have measured the EMC effect by tagging spectator neutrons, taking a major step toward solving the mystery.

    “We present initial and preliminary results from a new transformative measurement of a novel observable that provides direct insight into the origin of the EMC effect,” said Tyler T. Kutz, a postdoctoral researcher at The Massachusetts Institute of Technology (US) and Zuckerman Postdoctoral Scholar at The Tel Aviv University אוּנִיבֶרְסִיטַת תֵּל אָבִיב (IL), who will reveal the findings at the meeting.

    Inside the Backward Angle Neutron Detector (BAND) at Jefferson Lab, tagged spectator neutrons “split” the nuclear wave function into different sections. This process maps how momentum and density affect the structure of bound nucleons.

    The team’s initial results point to potential sizable, unpredicted effects. Preliminary observations suggest direct evidence that the EMC effect is connected with nucleon fluctuations of high local density and high momentum.

    “The results can have major implications for our understanding of the QCD structure of visible matter,” said Efrain Segarra, a graduate student at MIT working on the experiment. The research could shed light on the nature of confinement, strong interactions, and the fundamental composition of matter.

    A team from Fermilab found evidence that antimatter asymmetry also plays a crucial role in nucleon properties—a landmark observation published earlier this year in Nature. New analysis indicates that in the most extreme case, a single antiquark can be responsible for almost half the momentum of a proton.

    “This surprising result clearly shows that even at high momentum fractions, antimatter is an important part of the proton,” said Shivangi Prasad, a researcher at DOE’s Argonne National Laboratory (US). “It demonstrates the importance of nonperturbative approaches to the structure of the basic building block of matter, the proton.”

    Prasad will discuss the SeaQuest experiment that found more “down” antiquarks than “up” antiquarks within the proton. She will also share preliminary research on sea-quark and gluon distributions.

    “The SeaQuest Collaboration looked inside the proton by slamming a high-energy beam of protons into targets made of hydrogen (essentially protons) and deuterium (nuclei containing single protons and neutrons),” said Prasad.

    “Within the proton, quarks and antiquarks are held together by extremely strong nuclear forces—so great that they can create antimatter-matter quark pairs out of empty space!” she explained. But the subatomic pairings only exist for a fleeting moment before they annihilate.

    The antiquark results have renewed interest in several earlier explanations for antimatter asymmetry in the proton. Prasad plans to discuss future measurements that could test the proposed mechanisms.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition
    American Physical Society US)
    Physicists are drowning in a flood of research papers in their own fields and coping with an even larger deluge in other areas of physics. How can an active researcher stay informed about the most important developments in physics? Physics highlights a selection of papers from the Physical Review journals. In consultation with expert scientists, the editors choose these papers for their importance and/or intrinsic interest. To highlight these papers, Physics features three kinds of articles: Viewpoints are commentaries written by active researchers, who are asked to explain the results to physicists in other subfields. Focus stories are written by professional science writers in a journalistic style and are intended to be accessible to students and non-experts. Synopses are brief editor-written summaries.

     
  • richardmitnick 11:26 am on October 14, 2021 Permalink | Reply
    Tags: "3 things learned from IceCube's first 10 years", , , Particle Physics,   

    From The National Science Foundation (US) : “3 things learned from IceCube’s first 10 years” 

    From The National Science Foundation (US)

    October 14, 2021
    Lauren Lipuma

    Neutrinos are tiny, nearly massless elementary particles that rarely interact with normal matter. They were first made during the Big Bang and are continuously produced today by stars, black holes and other cosmic structures. Neutrinos are everywhere – billions pass through a square centimeter of Earth every second – but are difficult to detect and study.

    The largest neutrino observatory in the world, the IceCube Neutrino Observatory, consists of thousands of sensors draped through a cubic kilometer of ice at the geographic South Pole. It was built to study cosmic neutrinos – those that come from outside the solar system and are made in powerful cosmic objects like black holes and pulsars.

    Studying neutrinos is important for understanding the makeup of the universe, but IceCube, operated by The University of Wisconsin–Madison (US) and supported by The National Science Foundation (US), was designed to use neutrinos as an astronomical messenger: to tell researchers about the violent, chaotic environments in which they were created.

    In its first decade of operations, the ice-encased detector has given researchers new ways of looking at the cosmos. “Whenever we look at the universe with a new messenger, a particle we hadn’t had the capability to exploit before, we always learn new things,” said Dawn Williams, a physicist at the University of Alabama and member of the IceCube collaboration. The IceCube Observatory was “built to exploit this messenger – to use neutrinos to explore the universe, and we have succeeded … beyond our wildest dreams.”

    Here are three things scientists have learned from IceCube’s first decade of science and a peek at what physicists hope to learn in the future.

    1. High-energy neutrinos are being made outside the solar system.

    One of the first things physicists learned from IceCube is that there is indeed a flux of high-energy cosmic neutrinos detectable on Earth. Before IceCube was built, physicists had observed cosmic neutrinos directly only once before, when light and particles from a supernova reached Earth in 1987. Observatories around the world picked up 25 neutrinos from the explosion of a star in the Large Magellanic Cloud, a small companion galaxy of the Milky Way. But those neutrinos were low in energy. High-energy neutrinos from cosmic accelerators like black holes are much rarer and harder to detect.

    3
    Graphic: Lauren Lipuma

    In 2013, IceCube scientists announced they had detected 28 high-energy neutrinos, which was the first solid evidence for neutrinos coming from cosmic accelerators outside the solar system. These neutrinos were a million times more energetic than those from the 1987 supernova.

    2. Neutrino astronomy is a real thing.

    A few years after discovering a flux of cosmic neutrinos, IceCube accomplished its second major goal: identifying a candidate source of high-energy neutrinos. Physicists knew neutrinos are made in chaotic environments like black holes, but they had never pinpointed a specific object as being a high-energy neutrino “factory.”

    3
    Graphic: Lauren Lipuma.

    In 2017, IceCube scientists picked up a high-energy neutrino they traced to a flaring blazar, a giant elliptical galaxy with a supermassive black hole at its center. Black holes at the center of blazars have twin jets that spew light and elementary particles from their poles.

    That high-energy neutrino triggered IceCube’s automated alert system, which directed telescopes around the world to home in on the area of sky from which the neutrino originated. Several telescopes noticed a flare of gamma rays coming from a blazar about 4 billion light-years away. Astrophysicists concluded that this was the source of both the gamma rays and the high-energy neutrino they observed.

    Physicists then looked at past IceCube observations and found a bigger flux of neutrinos from three years earlier that originated from the same area of the sky – and presumably from the same blazar.

    This discovery was significant not only because it was the first time a high-energy neutrino source had been confirmed, but also because it ushered in the new era of neutrino astronomy: the idea of using neutrinos, rather than light, to study the universe.

    4
    Graphic: Lauren Lipuma.

    “Ten years ago, if I were giving a neutrino astronomy talk, I would have put neutrino astronomy in air quotes,” said Naoko Kurahashi Neilson, a physicist at Drexel University and member of the IceCube collaboration. “Ten years ago, we hadn’t even seen a neutrino from outside our solar system. Now I don’t put air quotes because everybody agrees you can do astronomy with neutrinos.”

    Since then, the IceCube team has identified one more potential cosmic neutrino
    source – the galaxy Messier 77, a starburst galaxy with a supermassive black hole at its center.

    3. IceCube can do fundamental physics.

    Two recent discoveries showed IceCube can help physicists understand the intrinsic properties and behaviors of neutrinos, even though it was not designed to do so. Neutrinos come in three “flavors,” a particle physics term for the species of elementary particles: electron, muon and tau neutrinos. Researchers have so far identified two candidate tau neutrinos.

    Physicists know neutrinos can change their flavor but not fully how or why this happens. IceCube’s observation of the two tau neutrinos means cosmic neutrinos are changing flavor somewhere on their journey across the universe, a process predicted by physics but difficult to observe.

    4
    A simulation of the photon burst detected during the Glashow resonance event. Each photon travels in a straight line until it is deflected by dust or other impurities in the ice surrounding IceCube’s sensors. Photo Credit: Lu Lu, IceCube Collaboration.

    Additionally, researchers detected an electron antineutrino indicative of a Glashow resonance event. This is an extremely rare type of interaction between an electron antineutrino and an atomic electron – a type of particle interaction never observed before. Physicist Sheldon Glashow first theorized the interaction in 1960, but only IceCube’s detection of an electron antineutrino in 2016 proved it happens in reality.

    “It’s incredible that we could actually achieve this,” said Francis Halzen, a physicist at the University of Wisconsin-Madison and principal investigator of the IceCube collaboration said. “I’m a particle physicist, and this to me is just mind-blowing.

    What’s next for IceCube?

    There are still many unanswered questions about cosmic neutrinos, but scientists suspect some will be answered in the next 10 years.

    5
    The server room at the IceCube Neutrino Observatory. Photo Credit: Benjamin Eberhardt; ICECUBE/National Science Foundation.

    Halzen hopes IceCube can help physicists understand where cosmic rays – high-energy charged particles that transfer their energy to neutrinos – come from. Unlike neutrinos, cosmic rays are charged, so their paths through the universe are warped by magnetic fields, making it nearly impossible for physicists to know where they came from without other information.

    Kurahashi Neilson hopes researchers can learn more about cosmic particle accelerators and when and how often they spew out neutrinos. “We’re at the tip of an iceberg, right? And we don’t know how big or deep or what shape the iceberg is. We know there are neutrino sources. We’ve maybe seen one or two, so what are the rest? When do they come out? How often? How are they distributed? What does the universe look like in neutrinos?” she said.

    ___________________________________________________________
    U Wisconsin IceCube neutrino observatory


    IceCube employs more than 5000 detectors lowered on 86 strings into almost 100 holes in the Antarctic ice NSF B. Gudbjartsson, IceCube Collaboration.

    Lunar Icecube

    IceCube Gen-2 DeepCore PINGU annotated

    IceCube neutrino detector interior.

    IceCube DeepCore annotated.

    IceCube Gen-2 DeepCore PINGU annotated

    DM-Ice II at IceCube annotated.
    ___________________________________________________________

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The National Science Foundation (NSF) (US) is an independent federal agency created by Congress in 1950 “to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense…we are the funding source for approximately 24 percent of all federally supported basic research conducted by America’s colleges and universities. In many fields such as mathematics, computer science and the social sciences, NSF is the major source of federal backing.

    We fulfill our mission chiefly by issuing limited-term grants — currently about 12,000 new awards per year, with an average duration of three years — to fund specific research proposals that have been judged the most promising by a rigorous and objective merit-review system. Most of these awards go to individuals or small groups of investigators. Others provide funding for research centers, instruments and facilities that allow scientists, engineers and students to work at the outermost frontiers of knowledge.

    NSF’s goals — discovery, learning, research infrastructure and stewardship — provide an integrated strategy to advance the frontiers of knowledge, cultivate a world-class, broadly inclusive science and engineering workforce and expand the scientific literacy of all citizens, build the nation’s research capability through investments in advanced instrumentation and facilities, and support excellence in science and engineering research and education through a capable and responsive organization. We like to say that NSF is “where discoveries begin.”

    Many of the discoveries and technological advances have been truly revolutionary. In the past few decades, NSF-funded researchers have won some 236 Nobel Prizes as well as other honors too numerous to list. These pioneers have included the scientists or teams that discovered many of the fundamental particles of matter, analyzed the cosmic microwaves left over from the earliest epoch of the universe, developed carbon-14 dating of ancient artifacts, decoded the genetics of viruses, and created an entirely new state of matter called a Bose-Einstein condensate.

    NSF also funds equipment that is needed by scientists and engineers but is often too expensive for any one group or researcher to afford. Examples of such major research equipment include giant optical and radio telescopes, Antarctic research sites, high-end computer facilities and ultra-high-speed connections, ships for ocean research, sensitive detectors of very subtle physical phenomena and gravitational wave observatories.

    Another essential element in NSF’s mission is support for science and engineering education, from pre-K through graduate school and beyond. The research we fund is thoroughly integrated with education to help ensure that there will always be plenty of skilled people available to work in new and emerging scientific, engineering and technological fields, and plenty of capable teachers to educate the next generation.

    No single factor is more important to the intellectual and economic progress of society, and to the enhanced well-being of its citizens, than the continuous acquisition of new knowledge. NSF is proud to be a major part of that process.

    Specifically, the Foundation’s organic legislation authorizes us to engage in the following activities:

    Initiate and support, through grants and contracts, scientific and engineering research and programs to strengthen scientific and engineering research potential, and education programs at all levels, and appraise the impact of research upon industrial development and the general welfare.
    Award graduate fellowships in the sciences and in engineering.
    Foster the interchange of scientific information among scientists and engineers in the United States and foreign countries.
    Foster and support the development and use of computers and other scientific methods and technologies, primarily for research and education in the sciences.
    Evaluate the status and needs of the various sciences and engineering and take into consideration the results of this evaluation in correlating our research and educational programs with other federal and non-federal programs.
    Provide a central clearinghouse for the collection, interpretation and analysis of data on scientific and technical resources in the United States, and provide a source of information for policy formulation by other federal agencies.
    Determine the total amount of federal money received by universities and appropriate organizations for the conduct of scientific and engineering research, including both basic and applied, and construction of facilities where such research is conducted, but excluding development, and report annually thereon to the President and the Congress.
    Initiate and support specific scientific and engineering activities in connection with matters relating to international cooperation, national security and the effects of scientific and technological applications upon society.
    Initiate and support scientific and engineering research, including applied research, at academic and other nonprofit institutions and, at the direction of the President, support applied research at other organizations.
    Recommend and encourage the pursuit of national policies for the promotion of basic research and education in the sciences and engineering. Strengthen research and education innovation in the sciences and engineering, including independent research by individuals, throughout the United States.
    Support activities designed to increase the participation of women and minorities and others underrepresented in science and technology.

    At present, NSF has a total workforce of about 2,100 at its Alexandria, VA, headquarters, including approximately 1,400 career employees, 200 scientists from research institutions on temporary duty, 450 contract workers and the staff of the NSB office and the Office of the Inspector General.

    NSF is divided into the following seven directorates that support science and engineering research and education: Biological Sciences, Computer and Information Science and Engineering, Engineering, Geosciences, Mathematical and Physical Sciences, Social, Behavioral and Economic Sciences, and Education and Human Resources. Each is headed by an assistant director and each is further subdivided into divisions like materials research, ocean sciences and behavioral and cognitive sciences.

    Within NSF’s Office of the Director, the Office of Integrative Activities also supports research and researchers. Other sections of NSF are devoted to financial management, award processing and monitoring, legal affairs, outreach and other functions. The Office of the Inspector General examines the foundation’s work and reports to the NSB and Congress.

    Each year, NSF supports an average of about 200,000 scientists, engineers, educators and students at universities, laboratories and field sites all over the United States and throughout the world, from Alaska to Alabama to Africa to Antarctica. You could say that NSF support goes “to the ends of the earth” to learn more about the planet and its inhabitants, and to produce fundamental discoveries that further the progress of research and lead to products and services that boost the economy and improve general health and well-being.

    As described in our strategic plan, NSF is the only federal agency whose mission includes support for all fields of fundamental science and engineering, except for medical sciences. NSF is tasked with keeping the United States at the leading edge of discovery in a wide range of scientific areas, from astronomy to geology to zoology. So, in addition to funding research in the traditional academic areas, the agency also supports “high risk, high pay off” ideas, novel collaborations and numerous projects that may seem like science fiction today, but which the public will take for granted tomorrow. And in every case, we ensure that research is fully integrated with education so that today’s revolutionary work will also be training tomorrow’s top scientists and engineers.

    Unlike many other federal agencies, NSF does not hire researchers or directly operate our own laboratories or similar facilities. Instead, we support scientists, engineers and educators directly through their own home institutions (typically universities and colleges). Similarly, we fund facilities and equipment such as telescopes, through cooperative agreements with research consortia that have competed successfully for limited-term management contracts.

    NSF’s job is to determine where the frontiers are, identify the leading U.S. pioneers in these fields and provide money and equipment to help them continue. The results can be transformative. For example, years before most people had heard of “nanotechnology,” NSF was supporting scientists and engineers who were learning how to detect, record and manipulate activity at the scale of individual atoms — the nanoscale. Today, scientists are adept at moving atoms around to create devices and materials with properties that are often more useful than those found in nature.

    Dozens of companies are gearing up to produce nanoscale products. NSF is funding the research projects, state-of-the-art facilities and educational opportunities that will teach new skills to the science and engineering students who will make up the nanotechnology workforce of tomorrow.

    At the same time, we are looking for the next frontier.

    NSF’s task of identifying and funding work at the frontiers of science and engineering is not a “top-down” process. NSF operates from the “bottom up,” keeping close track of research around the United States and the world, maintaining constant contact with the research community to identify ever-moving horizons of inquiry, monitoring which areas are most likely to result in spectacular progress and choosing the most promising people to conduct the research.

    NSF funds research and education in most fields of science and engineering. We do this through grants and cooperative agreements to more than 2,000 colleges, universities, K-12 school systems, businesses, informal science organizations and other research organizations throughout the U.S. The Foundation considers proposals submitted by organizations on behalf of individuals or groups for support in most fields of research. Interdisciplinary proposals also are eligible for consideration. Awardees are chosen from those who send us proposals asking for a specific amount of support for a specific project.

    Proposals may be submitted in response to the various funding opportunities that are announced on the NSF website. These funding opportunities fall into three categories — program descriptions, program announcements and program solicitations — and are the mechanisms NSF uses to generate funding requests. At any time, scientists and engineers are also welcome to send in unsolicited proposals for research and education projects, in any existing or emerging field. The Proposal and Award Policies and Procedures Guide (PAPPG) provides guidance on proposal preparation and submission and award management. At present, NSF receives more than 42,000 proposals per year.

    To ensure that proposals are evaluated in a fair, competitive, transparent and in-depth manner, we use a rigorous system of merit review. Nearly every proposal is evaluated by a minimum of three independent reviewers consisting of scientists, engineers and educators who do not work at NSF or for the institution that employs the proposing researchers. NSF selects the reviewers from among the national pool of experts in each field and their evaluations are confidential. On average, approximately 40,000 experts, knowledgeable about the current state of their field, give their time to serve as reviewers each year.

    The reviewer’s job is to decide which projects are of the very highest caliber. NSF’s merit review process, considered by some to be the “gold standard” of scientific review, ensures that many voices are heard and that only the best projects make it to the funding stage. An enormous amount of research, deliberation, thought and discussion goes into award decisions.

    The NSF program officer reviews the proposal and analyzes the input received from the external reviewers. After scientific, technical and programmatic review and consideration of appropriate factors, the program officer makes an “award” or “decline” recommendation to the division director. Final programmatic approval for a proposal is generally completed at NSF’s division level. A principal investigator (PI) whose proposal for NSF support has been declined will receive information and an explanation of the reason(s) for declination, along with copies of the reviews considered in making the decision. If that explanation does not satisfy the PI, he/she may request additional information from the cognizant NSF program officer or division director.

    If the program officer makes an award recommendation and the division director concurs, the recommendation is submitted to NSF’s Division of Grants and Agreements (DGA) for award processing. A DGA officer reviews the recommendation from the program division/office for business, financial and policy implications, and the processing and issuance of a grant or cooperative agreement. DGA generally makes awards to academic institutions within 30 days after the program division/office makes its recommendation.

     
  • richardmitnick 12:35 pm on October 13, 2021 Permalink | Reply
    Tags: "Levitation yields better neutron-lifetime measurement", , , , Particle Physics, ,   

    From DOE’s Los Alamos National Laboratory (US) via Science Alert (US) : “Levitation yields better neutron-lifetime measurement” 

    LANL bloc

    From DOE’s Los Alamos National Laboratory (US)

    via

    ScienceAlert

    Science Alert (US)

    13 OCTOBER 2021
    MICHELLE STARR

    1
    TanyaLovus/iStock/Getty Images Plus.

    We now know, to within a tenth of a percent, how long a neutron can survive outside the atomic nucleus before decaying into a proton.

    This is the most precise measurement yet of the lifespan of these fundamental particles, representing a more than two-fold improvement over previous measurements. This has implications for our understanding of how the first matter in the Universe was created from a soup of protons and neutrons in the minutes after the Big Bang.

    “The process by which a neutron ‘decays’ into a proton – with an emission of a light electron and an almost massless neutrino – is one of the most fascinating processes known to physicists,” said nuclear physicist Daniel Salvat of The Indiana University (US) Bloomington.

    “The effort to measure this value very precisely is significant because understanding the precise lifetime of the neutron can shed light on how the universe developed – as well as allow physicists to discover flaws in our model of the subatomic universe that we know exist but nobody has yet been able to find.”

    The research was conducted at The Los Alamos National Science Center, where a special experiment is set up just for trying to measure neutron lifespans. It’s called the UCNtau project, and it involves ultra-cold neutrons (UCNs) stored in a magneto-gravitational trap.

    The neutrons are cooled almost to absolute zero, and placed in the trap, a bowl-shaped chamber lined with thousands of permanent magnets, which levitate the neutrons, inside a vacuum jacket.

    The magnetic field prevents the neutrons from depolarizing and, combined with gravity, keeps the neutrons from escaping. This design allows neutrons to be stored for up to 11 days.

    The researchers stored their neutrons in the UCNtau trap for 30 to 90 minutes, then counted the remaining particles after the allotted time. Over the course of repeated experiments, conducted between 2017 and 2019, they counted over 40 million neutrons, obtaining enough statistical data to determine the particles’ lifespan with the greatest precision yet.

    This lifespan is around 877.75 ± 0.28 seconds (14 minutes and 38 seconds), according to the researchers’ analysis. The refined measurement can help place important physical constraints on the Universe, including the formation of matter and dark matter.

    After the Big Bang, things happened relatively quickly. In the very first moments, the hot, ultra-dense matter that filled the Universe cooled into quarks and electrons; just millionths of a second later, the quarks coalesced into protons and neutrons.

    Knowing the lifespan of the neutron can help physicists understand what role, if any, decaying neutrons play in the formation of the mysterious mass in the Universe known as dark matter. This information can also help test the validity of something called the Cabibbo-Kobayashi-Maskawa matrix, which helps explain the behavior of quarks under the Standard Model of physics, the researchers said.

    “The underlying model explaining neutron decay involves the quarks changing their identities, but recently improved calculations suggest this process may not occur as previously predicted,” Salvat said.

    “Our new measurement of the neutron lifetime will provide an independent assessment to settle this issue, or provide much-searched-for evidence for the discovery of new physics.”

    The research has been accepted into Physical Review Letters.

    See the full article here .

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    DOE’s Los Alamos National Laboratory (US) mission is to solve national security challenges through scientific excellence.

    LANL campus
    DOE’s Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is managed by Triad, a public service oriented, national security science organization equally owned by its three founding members: The University of California Texas A&M University (US), Battelle Memorial Institute (Battelle) for the Department of Energy’s National Nuclear Security Administration. Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    DOE’s Los Alamos National Laboratory (US) mission is to solve national security challenges through scientific excellence.

    LANL campus
    DOE’s Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is managed by Triad, a public service oriented, national security science organization equally owned by its three founding members: The University of California Texas A&M University (US), Battelle Memorial Institute (Battelle) for the Department of Energy’s National Nuclear Security Administration. Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

     
  • richardmitnick 11:57 am on October 13, 2021 Permalink | Reply
    Tags: "How to force photons to never bounce back", , Particle Physics, , , Topological insulators are materials whose structure forces photons and electrons to move only along the material’s boundary and only in one direction.   

    From Swiss Federal Institute of Technology in Lausanne [EPFL-École Polytechnique Fédérale de Lausanne] (CH): “How to force photons to never bounce back” 

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

    13.10.21
    Florent Hiard

    EPFL scientists have developed a topology-based method that forces microwave photons to travel along a one way path, despite unprecedented levels of disorder and obstacles on their way. This discovery paves the way to a new generation of high-frequency circuits and extremely robust, compact communication devices.

    1

    Topological insulators are materials whose structure forces photons and electrons to move only along the material’s boundary and only in one direction. These particles experience very little resistance and travel freely past obstacles such as impurities, fabrication defects, a change of signal’s trajectory within a circuit, or objects placed intentionally in the particles’ path. That’s because these particles, instead of being reflected by the obstacle, go around it “like river-water flowing past a rock,” says Prof. Romain Fleury, head of EPFL’s Laboratory of Wave Engineering, within the School of Engineering.

    Until now, these particles’ exceptional resilience to obstacles applied only to limited perturbations in the material, meaning this property couldn’t be exploited widely in photonics-based applications. However, that could soon change thanks to research being conducted by Prof. Fleury along with his PhD student Zhe Zhang and Pierre Delplace from the Lyon Physics Laboratory [Laboratoire de Physique ENS de Lyon](FR). Their study, appearing in the renowned journal Nature, introduces a topological insulator in which the transmission of microwave photons can survive unprecedented levels of disorder.

    “We were able to create a rare topological phase that can be characterized as an anomalous topological insulator. This phase arises from the mathematical properties of unitary groups and gives the material unique – and unexpected – transmission properties,” says Zhang.

    This discovery holds great promise for new advances in science and technology. “When engineers design hyperfrequency circuits, they have to be very careful to make sure that waves are not reflected but rather guided along a given path and through a series of components. That’s the first thing I teach my electrical engineering students,” says Prof. Fleury. “This intrinsic constraint, known as impedance matching, limits our ability to manipulate wave signals. However, with our discovery, we can take a completely different approach, by using topology to build circuits and devices without having to worry about impedance matching – a factor that currently restricts the scope of modern technology.”

    2
    Topological isolators with reconfigurable functionality © Zhe Zhang / EPFL 2021.

    Prof. Fleury’s lab is now working on concrete applications for their new topological insulator. “These types of topological circuits could be extremely useful for developing next-generation communication systems,” he says. “Such systems require circuits that are highly reliable and easily reconfigurable.” His research group is also looking at how the discovery could be used for developing new kinds of photonic processors and quantum computers.

    See the full article here .

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    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 10:32 am on October 12, 2021 Permalink | Reply
    Tags: "Research Team Unlocks Secret Path to a Quantum Future", A spin defect in the right crystal background can approach perfect quantum coherence while possessing greatly improved robustness and functionality., , , , Particle Physics, These imperfections can be used to make high-precision sensing platforms.   

    From DOE’s Lawrence Berkeley National Laboratory (US) : “Research Team Unlocks Secret Path to a Quantum Future” 

    From DOE’s Lawrence Berkeley National Laboratory (US)

    October 12, 2021
    Rachel Berkowitz

    1
    Artist’s illustration of hydrodynamical behavior from an interacting ensemble of quantum spin defects in diamond. Credit: Norman Yao/Berkeley Lab.

    In 1998, researchers including Mark Kubinec of The University of California-Berkeley (US) performed one of the first simple quantum computations using individual molecules. They used pulses of radio waves to flip the spins of two nuclei in a molecule, with each spin’s “up” or “down” orientation storing information in the way that a “0” or “1” state stores information in a classical data bit. In those early days of quantum computers, the combined orientation of the two nuclei – that is, the molecule’s quantum state – could only be preserved for brief periods in specially tuned environments. In other words, the system quickly lost its coherence. Control over quantum coherence is the missing step to building scalable quantum computers.

    Now, researchers are developing new pathways to create and protect quantum coherence. Doing so will enable exquisitely sensitive measurement and information processing devices that function at ambient or even extreme conditions. In 2018, Joel Moore, a senior faculty scientist at Lawrence Berkeley National Laboratory (Berkeley Lab) and professor at The University of California-Berkeley (US), secured funds from The Department of Energy (US) to create and lead the DOE Center for Nanoscale Control of Geologic CO2 (EFRC) – called the Center for Novel Pathways to Quantum Coherence in Materials (NPQC) – to further those efforts. “The EFRCs are an important tool for DOE to enable focused inter-institutional collaborations to make rapid progress on forefront science problems that are beyond the scope of individual investigators,” said Moore.

    Through the NPQC, scientists from Berkeley Lab, The University of California-Berkeley, The University of California-Santa Barbara (US), DOE’s Argonne National Laboratory (US), and Columbia University (US) are leading the way to understand and manipulate coherence in a variety of solid-state systems. Their threefold approach focuses on developing novel platforms for quantum sensing; designing two-dimensional materials that host complex quantum states; and exploring ways to precisely control a material’s electronic and magnetic properties via quantum processes. The solution to these problems lies within the materials science community. Developing the ability to manipulate coherence in realistic environments requires in-depth understanding of materials that could provide alternate quantum bit (or “qubit”), sensing, or optical technologies.

    Basic discoveries underlie further developments that will contribute to other DOE investments across The DOE Office of Science (US). As the program enters its fourth year, several breakthroughs are laying the scientific groundwork for innovations in quantum information science.

    More defects, more opportunities

    Many of NPQC’s achievements thus far focus on quantum platforms that are based on specific flaws in a material’s structure called spin defects. A spin defect in the right crystal background can approach perfect quantum coherence while possessing greatly improved robustness and functionality.

    These imperfections can be used to make high-precision sensing platforms. Each spin defect responds to extremely subtle fluctuations in the environment; and coherent collections of defects can achieve unprecedented accuracy and precision. But understanding how coherence evolves in a system of many spins, where all the spins interact with one another, is daunting. To meet this challenge, NPQC researchers are turning to a common material that turns out to be ideal for quantum sensing: diamond.

    3
    During diamond’s formation, replacement of a carbon atom (green) with a nitrogen atom (yellow, N) and omitting another to leave a vacancy (purple, V) creates a common defect that has well-defined spin properties. (Credit: The National Institute of Standards and Technology (US))

    In nature, each carbon atom in a diamond’s crystal structure connects to four other carbon atoms. When one carbon atom is replaced by a different atom or omitted altogether, which commonly occurs as the diamond’s crystal structure forms, the resulting defect can sometimes behave like an atomic system that has a well-defined spin – an intrinsic form of angular momentum carried by electrons or other subatomic particles. Much like these particles, certain defects in diamond can have an orientation, or polarization, that is either “spin-up” or “spin-down.”

    By engineering multiple different spin defects into a diamond lattice, Norman Yao, a faculty scientist at Berkeley Lab and an assistant professor of physics at The University of California-Berkeley , and his colleagues created a 3D system with spins dispersed throughout the volume. Within that system, the researchers developed a way to probe the “motion” of spin polarization at tiny length scales.

    3
    Schematic depicting a central pocket of excess spin (turquoise shading) in a diamond cube, which then spread out much like dye in a liquid. Credit: Berkeley Lab.

    Using a combination of measurement techniques, the researchers found that spin moves around in the quantum mechanical system in almost the same way that dye moves in a liquid. Learning from dyes has turned out to be a successful path toward understanding quantum coherence, as recently published in the journal Nature. Not only does the emergent behavior of spin provide a powerful classical framework for understanding quantum dynamics, but the multi-defect system provides an experimental platform for exploring how coherence works as well. Moore, the NPQC director and a member of the team who has previously studied other kinds of quantum dynamics, described the NPQC platform as “a uniquely controllable example of the interplay between disorder, long-ranged dipolar interactions between spins, and quantum coherence.”

    Those spin defects’ coherence times depend heavily on their immediate surroundings. Many NPQC breakthroughs have centered on creating and mapping the strain sensitivity in the structure surrounding individual defects in diamond and other materials. Doing so can reveal how best to engineer defects that have the longest possible coherence times in 3D and 2D materials. But exactly how might the changes imposed by forces on the material itself correlate to changes in the defect’s coherence?

    To find out, NPQC researchers are developing a technique for creating deformed areas in a host crystal and measuring the strain. “If you think about atoms in a lattice in terms of a box spring, you get different results depending on how you push on them,” said Martin Holt, group leader in electron and X-ray microscopy at Argonne National Laboratory and a principal investigator with NPQC. Using the Advanced Photon Source and Center for Nanoscale Materials, both user facilities at Argonne National Laboratory, he and his colleagues offer a direct image of the deformed areas in a host crystal. Until now, a defect’s orientation in a sample has been mostly random. The images reveal which orientations are the most sensitive, providing a promising avenue for high-pressure quantum sensing.

    4
    Scientists at Berkeley Lab and UC Berkeley unexpectedly discovered superconductivity in a triple layer of carbon sheets. Credit: Feng Wang and Guorui Chen/Berkeley Lab.

    “It’s really beautiful that you can take something like diamond and bring utility to it. Having something simple enough to understand the basic physics but that also can be manipulated enough to do complex physics is great,” said Holt.

    Another goal for this research is the ability to transfer a quantum state, like that of a defect in diamond, coherently from one point to another using electrons. Work by NPQC scientists at Berkeley Lab and Argonne Lab studies special quantum wires that appear in atomically thin layers of some materials. Superconductivity was unexpectedly discovered in one such system, a triple layer of carbon sheets, by the group led by Feng Wang, a Berkeley Lab faculty senior scientist and UC Berkeley professor, and leader of NPQC’s effort in atomically thin materials. Of this work, published in Nature in 2019, Wang said, “The fact that the same materials can offer both protected one-dimensional conduction and superconductivity opens up some new possibilities for protecting and transferring quantum coherence.”

    Toward useful devices

    Multi-defect systems are not only important as fundamental science knowledge. They also have the potential to become transformative technologies. In novel two-dimensional materials that are paving the way for ultra-fast electronics and ultra-stable sensors, NPQC researchers investigate how spin defects may be used to control the material’s electronic and magnetic properties. Recent findings have offered some surprises.

    “A fundamental understanding of nanoscale magnetic materials and their applications in spintronics has already led to an enormous transformation in magnetic storage and sensor devices. Exploiting quantum coherence in magnetic materials could be the next leap towards low-power electronics,” said Peter Fischer, senior scientist and division deputy in the Materials Sciences Division at Berkeley Lab.

    A material’s magnetic properties depend entirely on the alignment of spins in adjacent atoms. Unlike the neatly aligned spins in a typical refrigerator magnet or the magnets used in classical data storage, antiferromagnets have adjacent spins that point in opposite directions and effectively cancel each other out. As a result, antiferromagnets don’t “act” magnetic and are extremely robust to external disturbances. Researchers have long sought ways to use them in spin-based electronics, where information is transported by spin instead of charge. Key to doing so is finding a way to manipulate spin orientation and maintain coherence.

    5
    An exotic magnetic device could further miniaturize computing devices and personal electronics without loss of performance. Scale bar shown above is 10 micrometers. Credit: James Analytis/Berkeley Lab.

    In 2019 NPQC researchers led by James Analytis, a faculty scientist at Berkeley Lab and associate professor of physics at UC Berkeley, with postdoc Eran Maniv, observed that applying a small, single pulse of electrical current to tiny flakes of an antiferromagnet caused the spins to rotate and “switch” their orientation. As a result, the material’s properties could be tuned extremely quickly and precisely. “Understanding the physics behind this will require more experimental observations and some theoretical modeling,” said Maniv. “New materials could help reveal how it works. This is the beginning of a new research field.”

    Now, the researchers are working to pinpoint the exact mechanism that drives that switching in materials fabricated and characterized at the Molecular Foundry, a user facility at Berkeley Lab. Recent findings, published in Science Advances and Nature Physics, suggest that fine-tuning the defects in a layered material could provide a reliable means of controlling the spin pattern in new device platforms. “This is a remarkable example of how having many defects lets us stabilize a switchable magnetic structure,” said Moore, the NPQC leader.

    Spinning new threads

    In its next year of operation, NPQC will build on this year’s progress. Goals include exploring how multiple defects interact in two-dimensional materials and investigating new kinds of one-dimensional structures that could arise. These lower-dimensional structures could prove themselves as sensors for detecting other materials’ smallest-scale properties. Additionally, focusing on how electric currents can manipulate spin-derived magnetic properties will directly link fundamental science to applied technologies.

    Rapid progress in these tasks requires the combination of techniques and expertise that can only be created within a large collaborative framework. “You don’t develop capabilities in isolation,” said Holt. “The NPQC provides the dynamic research environment that drives the science and harnesses what each lab or facility is doing.” The research center meanwhile provides a unique education at the frontiers of science including opportunities for developing the scientific workforce that will lead the future quantum industry.

    The NPQC brings a new set of questions and goals to the study of the basic physics of quantum materials. Moore said, “Quantum mechanics governs the behavior of electrons in solids, and this behavior is the basis for much of the modern technology we take for granted. But we are now at the beginning of the second quantum revolution, where properties like coherence take center stage, and understanding how to enhance these properties opens a new set of questions about materials for us to answer.”

    See the full article here .

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    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 9:37 am on October 12, 2021 Permalink | Reply
    Tags: "Is dark matter cold or warm or hot?", , , , , , Particle Physics, , , ,   

    From Symmetry: “Is dark matter cold or warm or hot?” 

    Symmetry Mag

    From Symmetry

    10/12/21
    Glennda Chui

    The answer has to do with dark matter’s role in shaping the cosmos.

    Milky Way Dark Matter Halo Credit:L. Calçada/ European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte](EU)(CL)

    Half a century after Vera Rubin and Kent Ford confirmed that a form of invisible matter—now called dark matter—is required to account for the rotation of galaxies, the evidence for its existence is overwhelming.
    _____________________________________________________________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky from http:// palomarskies.blogspot.com.

    Coma cluster via NASA/ESA Hubble.

    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).

    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL).

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970

    Dark Matter Research

    Inside the Axion Dark Matter eXperiment U Washington (US) Credit : Mark Stone U. of Washington. Axion Dark Matter Experiment.
    _____________________________________________________________________________________

    Although it is known to interact with ordinary matter only through gravity, there is such a massive amount of dark matter out there—85% of all the matter in the universe—that it has played a pivotal behind-the-scenes role in shaping all the stuff we can see, from our own Milky Way galaxy to the wispy filaments of gas that link galaxies across vast distances.

    “We think it exists because there’s evidence for it on many, many scales,” says Kevork Abazajian, a theoretical physicist and astrophysicist at The University of California-Irvine (US).

    There have been a lot of ideas about what form dark matter might take, from planet-sized objects called MACHOs to individual particles like WIMPs—weakly interacting massive particles roughly the size of a proton—and even tinier things like axions and sterile neutrinos.

    In the 1980s, scientists came up with a way to make sense of this growing collection: They started classifying proposed dark-matter particles as cold, warm or hot. These categories are based on how fast each type of dark matter would have traveled through the early universe—a speed that depended on its mass—and on how hot its surroundings were when it popped into existence.

    Light, fast particles are known as hot dark matter; heavy, slow ones are cold dark matter; and warm dark matter falls in between.

    In this way of seeing things, WIMPs are cold, sterile neutrinos are warm, and relic neutrinos from the early universe are hot. (Axions are a special case—both light and extremely cold. We’ll get to them later.)

    Why is their speed so important?

    “If a dark matter particle is lighter and faster, it can travel farther in a given time, and it will smooth out any structure that already exists along the way,” Abazajian says.

    On the other hand, slower, colder forms of dark matter would have helped build structure, and based on what we know and see today it must have been part of the mix.

    Building galaxies

    Although there are theories about when and how each type of dark-matter candidate would have formed, the only thing scientists know for sure is that dark matter was already around about 75,000 years after the Big Bang. It was then that matter started to dominate over radiation and little seeds of structure started to form, says Stanford University (US) theoretical physicist Peter Graham.

    Most types of dark-matter particles would have been created by collisions between other particles in the hot, dense soup of the infant universe, in much the same way that high-energy particle collisions at places like the Large Hadron Collider give rise to exotic new types of particles. As the universe expanded and cooled, dark-matter particles would have wound up being hot, warm or cold—and, in fact, there could have been more than one type.

    Scientists describe them as freely “streaming” through the universe, although this term is a little misleading, Abazajian says. Unlike leaves floating on a river, all headed in the same direction in a coordinated way, “these things are not just in one place and then in another place,” he says. “They’re everywhere and going in every direction.”

    As it streamed, each type of dark matter would have had a distinctive impact on the growth of structure along the way—either adding to its clumpiness, and thus to the building of galaxies, or thwarting their growth.

    Cold dark matter, such as the WIMP, would have been a clump-builder. It moved slowly enough to glom together and form gravitational wells, which would have captured nearby bits of matter.

    Hot dark matter, on the other hand, would have been a clump-smoother, zipping by so fast that it could ignore those gravitational wells. If all dark matter were hot, none of those seeds could have grown into bigger structures, says Silvia Pascoli, a theoretical physicist at The University of Bologna [Alma mater studiorum – Università di Bologna](IT). That’s why scientists now believe that hot dark-matter particles, such as relic neutrinos from the early days of the cosmos, could not constitute more than a sliver of dark matter as a whole.

    Despite their tiny contribution, Pascoli adds, “I say these relic neutrinos are currently the only known component of dark matter. They have an important impact on the evolution of the universe.”

    You might think that warm dark matter would be the best dark matter, filling the universe with a Goldilocks bowl of just-right structure. Sterile neutrinos are considered the top candidate in this category, and in theory they could indeed constitute the vast majority of dark matter.

    But most of the parameter space—the sets of conditions—where they could exist have been ruled out, says Abazajian, who as a graduate student researched how specific types of neutrino oscillations in the early universe could have produced sterile neutrino dark matter.

    Although those same oscillations could be happening today, he says, the probability that a regular neutrino would turn into a sterile one through standard oscillations in the vacuum of space are thought to be very small, with estimates ranging from 1 in 100,000 to 1 in 100 trillion.

    “You’d have to have a very good counting mechanism to count up to 100 trillion hits in your detector without missing the one hit from a sterile neutrino,” Abazajian says.

    That said, there are a few experiments out there that are giving it a try, using new approaches that don’t rely on direct hits.

    Then there’s the axion.

    Unlike the other dark-matter candidates, axions would be both extremely light—so light that they are better described as waves whose associated fields can spread over kilometers—and extremely cold, Graham says. They are so weakly coupled to other forms of matter that the frantic collisions of particles in the thermal bath of the early universe would have produced hardly any.

    “They would have been produced in a different way than the other dark matter candidates,” Graham says. “Even though the universe was very hot at the time, axions would have been very cold at birth and would stay cold forever, which means that they are absolutely cold dark matter.”

    Even though axions are very light, Graham says, “because they exist at close to absolute zero, the temperature where all motion stops, they are essentially not moving. They’re kind of this ghostly fluid, and everything else moves through it.”

    Searching for dark matter of all kinds

    Some scientists think it will take more than one type of dark matter to account for all the things we see in the universe.

    And in the past few years, as experiments aimed at detecting WIMPs and producing dark matter particles through collisions at the Large Hadron Collider have so far come up empty-handed, the search for dark matter has broadened.

    SixTRack CERN LHC particles

    The proliferation of ideas for searches has been helped by technological advances and clever approaches that could force much lighter and even more exotic dark-matter particles out of hiding.

    Some of those efforts make use of the very clumpiness that dark matter was instrumental in creating.

    Simona Murgia, an experimentalist at The University of California-Irvine (US), led a team looking for signs of collisions between WIMPs and their antiparticles with the Fermi Gamma-ray Space Telescope while a postdoc at the DOE’s SLAC National Accelerator Laboratory.

    Now she’s joined an international team of scientists who will conduct a vast survey of the Southern sky from the Vera C. Rubin Observatory in Chile using the world’s biggest digital camera, which is under construction at SLAC.

    NSF (US) NOIRLab (US) NOAO (US) Vera C. Rubin Observatory [LSST] Telescope currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing NSF (US) NOIRLab (US) NOAO (US) AURA (US) Gemini South Telescope and Southern Astrophysical Research Telescope.

    One of the things this survey will do is get a much better handle on the distribution of dark matter in the universe by looking at how it bends light from the galaxies we can see.

    “It will tell us something about the nature of dark matter in a totally different way,” Murgia says. “The more clumpy its distribution is, the more consistent it is with theories that tell you dark matter is cold.”

    The camera is expected to snap images of about 20 billion galaxies over 10 years, and from those images scientists hope to infer the fundamental nature of the dark matter that shaped them.

    “We don’t only want to know the dark matter is there,” Murgia says. “We do want to understand the cosmology, but we also really want to know what dark matter is.”

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 9:52 pm on October 11, 2021 Permalink | Reply
    Tags: Particle Physics, , , , , "The Search for Quantum Gravity"   

    From The University of California-Santa Barbara (US) : “The Search for Quantum Gravity” 

    UC Santa Barbara Name bloc

    From The University of California-Santa Barbara (US)

    October 11, 2021

    Sonia Fernandez
    sonia.fernandez@ucsb.edu

    With support from The Heising-Simons Foundation (US), theoretical physicists take a new approach to the search for quantum gravity.

    1
    Quantum Gravity Illustration

    About a century ago, Albert Einstein amazed the world with his groundbreaking theory of relativity, and ever since he shared this profound understanding of gravity and spacetime, physicists everywhere have worked hard to prove, refine and extend it. In the intervening decades, numerous observations have borne Einstein out, with phenomena such as gravitational lensing and redshift, shifts in planetary orbit and, more recently, gravitational waves and observations of black holes.

    However, for all the advances we’ve made in witnessing the more readily observable, macro effects of gravity, there remains a gap — a chasm, really — in our ability to understand gravity in the context of another profound discovery: quantum mechanics, the physics of matter and energy at their smallest scales.

    “There is the longstanding problem, perhaps the greatest remaining from 20th century physics, of reconciling quantum mechanics with gravity,” said UC Santa Barbara theoretical physicist Steven Giddings. The universe is quantum, and unlike the other fundamental forces — the electromagnetic, the weak and the strong nuclear forces — which have been described within quantum field theory, what we know of gravitation remains solidly in the realm of classical physics.

    “Associated with that problem is a gulf between theory and observation,” said Giddings, who specializes in high energy and gravitational theory, as well as quantum black holes, quantum cosmology and other quantum aspects of gravity. Traditional thinking leads one to believe that quantum aspects of gravity are only observable if we explore incredibly short distances, he said, such as the Planck length (10-35 meter), thought to be the smallest length in the universe and the length at which quantum gravity effects become important. It’s also far beyond observational reach.

    But what if it was possible to detect quantum gravity at longer, observable length scales? Giddings, and fellow theorists Kathryn Zurek and Yanbei Chen at The California Institute of Technology (US), Cynthia Keeler and Maulik Parikh at The Arizona State University (US), and Ben Freivogel and Erik Verlinde at The University of Amsterdam [Universiteit van Amsterdam](NL), think that could be the case.

    “Various theoretical developments have indicated that quantum gravity effects may become important at much greater distances in certain contexts, and that is truly exciting and worth exploring,” Giddings said. “We are taking this seriously.”

    And, thanks to support from the Heising-Simons Foundation, the team is poised to bridge that chasm, by exploring ways in which quantum gravity may be observed, via effects a longer length scales.

    “We are thrilled that the Heising-Simons Foundation has chosen to support this vision of exploring new effects, particularly at long distances, in quantum gravity, and the possibility that they lead to observational effects,” Giddings said of the $3.1 million in multi-institution grants to help the team push the boundaries of our knowledge of quantum gravity. “Their support should really move this research forward.”

    Quantum Effects at Longer Lengths

    Reconciling relativity to quantum mechanics has challenged physicists for the better part of a century, with puzzles such as the black hole information paradox. That’s where relativity and quantum mechanics violently conflict on the issue of what happens to information that falls into a black hole, those extremely high-gravity voids in spacetime. A relativistic picture indicates that the information gets destroyed as the black hole slowly evaporates, while quantum mechanics states that that information cannot be destroyed.

    A suggested approach to that conundrum and other similarly complex issues emerges with the proposed holographic principle, a fundamentally new idea about the possible behavior of quantum gravity.

    “There are different ways to explain it, but one is that the amount of information you can put in a volume is not proportional to the volume but to the surface area surrounding the volume,” Giddings explained. A consistent theory incorporating this principle might explain how information is not destroyed, resulting in a relativistic object, such as a black hole, obeying quantum rules.

    “When one tries to reconcile the existence of black holes with the principles of quantum mechanics, one seems to be led to the conclusion that new quantum gravity effects must become important not just at short distances, but at distances comparable to the size of the black hole in question — for the largest black holes we know, many times the size of our solar system,” Giddings said.

    The principle, which started out originally with black holes, has been suggested to extend to the universe in general — what we perceive as our three-dimensional reality may even, in a sense, have an underlying two-dimensional description. This could make its mathematical description more elegant and compelling.

    “This is a big departure from the properties of quantum field theories that describe other forces of nature — like electromagnetism and the strong force — and is a feature of gravity that strongly suggests that a theory of gravity has a very different underlying structure,” he added. This fundamentally different structure might be part of a description with novel properties, in which information is preserved.

    A related argument for the observability of quantum gravity at greater distances comes from the notion that very high energy collisions, though far beyond what we have been able to accomplish, start producing quantum gravitational effects at increasingly large distances.

    “When one considers extremely high energy collisions of particles, one is not probing shorter distances any longer — as has been true at accessible energies — but instead one starts to see effects at longer distances, due to basic properties of gravity,” Giddings said.

    Quantum Gravity at Work

    Recent developments in experimental observations have made it possible to detect and measure new effects of gravity, such as with Caltech’s Laser Interferometer Gravitational Wave Observatory (LIGO), the Virgo interferometer in Italy, and the Kamioka Gravitational Wave Detector (KAGRA) in Japan.

    _______________________________________________________________________________________
    LIGOVIRGOKAGRA

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA.

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    KAGRA Large-scale Cryogenic Gravitational Wave Telescope Project (JP)
    _______________________________________________________________________________________
    Each of those facilities is turned to space to sense gravitational waves coming from major events, such as the mergers of massive celestial bodies like black holes and neutron stars. These, as well as observations of light from near black holes by The Event Horizon Telescope-EHT, may also be sensitive to long-range quantum effects. In addition, ideas related to holography suggest the possibility of new quantum effects in lab-based settings, and newer experiments with interferometers may provide novel ways to test them.

    The task for the researchers as they resolve foundational issues and understand aspects of the fundamental description of quantum gravity, is to develop “effective descriptions” that can connect theory with observations coming in from the interferometers and other instruments.

    “In physics, we have often been in the situation where we don’t have the complete theory, but we have an approximate description that captures certain important properties of that theory,” Giddings explained. “Often, such ‘effective descriptions’ can be surprisingly powerful, and lead to deeper insight about the more fundamental theory.”

    The group’s diverse mix of backgrounds is a strength of this collaboration, with specializations ranging from quantum gravity to particle physics, string theory to gravitational wave physics. Through a series of meetings to be held over four years the collaboration will progress from foundational issues, such as sharpening the description of holography and understanding the mathematical structure of gravity, to studying models that may describe behavior of quantum gravity, its interactions and potentially observable effects, to developing specific observational tests with the interferometers and observations of black holes.

    Along the way, the collaboration will grow, starting with the seven core members and adding postdoctoral fellows and graduate students, and finally broadening activities to include additional physicists to discuss collaboration results and related theoretical advances from the broader community.

    “If we are able to observe quantum effects of black holes, that will be truly revolutionary,” Giddings said. “It would also likely help guide the conceptual revolution of reconciling quantum mechanics with gravity, which we expect to likely be as profound as the revolutionary discovery of quantum mechanics.”

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    UC Santa Barbara Seal

    The University of California-Santa Barbara (US) is a public land-grant research university in Santa Barbara, California, and one of the ten campuses of the University of California (US) system. Tracing its roots back to 1891 as an independent teachers’ college, The University of California-Santa Barbara joined the University of California system in 1944, and is the third-oldest undergraduate campus in the system.

    The university is a comprehensive doctoral university and is organized into five colleges and schools offering 87 undergraduate degrees and 55 graduate degrees. It is classified among “R1: Doctoral Universities – Very high research activity”. According to the National Science Foundation (US), The University of California-Santa Barbara spent $235 million on research and development in fiscal year 2018, ranking it 100th in the nation. In his 2001 book The Public Ivies: America’s Flagship Public Universities, author Howard Greene labeled The University of California-Santa Barbara a “Public Ivy”.

    The University of California-Santa Barbara is a research university with 10 national research centers, including the Kavli Institute for Theoretical Physics (US) and the Center for Control, Dynamical-Systems and Computation. Current University of California-Santa Barbara faculty includes six Nobel Prize laureates; one Fields Medalist; 39 members of the National Academy of Sciences (US); 27 members of the National Academy of Engineering (US); and 34 members of the American Academy of Arts and Sciences (US). The University of California-Santa Barbara was the No. 3 host on the ARPANET and was elected to the Association of American Universities in 1995. The faculty also includes two Academy and Emmy Award winners and recipients of a Millennium Technology Prize; an IEEE Medal of Honor; a National Medal of Technology and Innovation; and a Breakthrough Prize in Fundamental Physics.
    The University of California-Santa Barbara Gauchos compete in the Big West Conference of the NCAA Division I. The Gauchos have won NCAA national championships in men’s soccer and men’s water polo.

    History

    The University of California-Santa Barbara traces its origins back to the Anna Blake School, which was founded in 1891, and offered training in home economics and industrial arts. The Anna Blake School was taken over by the state in 1909 and became the Santa Barbara State Normal School which then became the Santa Barbara State College in 1921.

    In 1944, intense lobbying by an interest group in the City of Santa Barbara led by Thomas Storke and Pearl Chase persuaded the State Legislature, Gov. Earl Warren, and the Regents of the University of California to move the State College over to the more research-oriented University of California system. The State College system sued to stop the takeover but the governor did not support the suit. A state constitutional amendment was passed in 1946 to stop subsequent conversions of State Colleges to University of California campuses.

    From 1944 to 1958, the school was known as Santa Barbara College of the University of California, before taking on its current name. When the vacated Marine Corps training station in Goleta was purchased for the rapidly growing college Santa Barbara City College moved into the vacated State College buildings.

    Originally the regents envisioned a small several thousand–student liberal arts college a so-called “Williams College (US) of the West”, at Santa Barbara. Chronologically, The University of California-Santa Barbara is the third general-education campus of the University of California, after The University of California-Berkeley (US) and The University of California-Los Angeles (US) (the only other state campus to have been acquired by the UC system). The original campus the regents acquired in Santa Barbara was located on only 100 acres (40 ha) of largely unusable land on a seaside mesa. The availability of a 400-acre (160 ha) portion of the land used as Marine Corps Air Station Santa Barbara until 1946 on another seaside mesa in Goleta, which the regents could acquire for free from the federal government, led to that site becoming the Santa Barbara campus in 1949.

    Originally only 3000–3500 students were anticipated but the post-WWII baby boom led to the designation of general campus in 1958 along with a name change from “Santa Barbara College” to “University of California-Santa Barbara,” and the discontinuation of the industrial arts program for which the state college was famous. A chancellor- Samuel B. Gould- was appointed in 1959.

    In 1959 The University of California-Santa Barbara professor Douwe Stuurman hosted the English writer Aldous Huxley as the university’s first visiting professor. Huxley delivered a lectures series called The Human Situation.

    In the late ’60s and early ’70s The University of California-Santa Barbara became nationally known as a hotbed of anti–Vietnam War activity. A bombing at the school’s faculty club in 1969 killed the caretaker Dover Sharp. In the spring of 1970 multiple occasions of arson occurred including a burning of the Bank of America branch building in the student community of Isla Vista during which time one male student Kevin Moran was shot and killed by police. The University of California-Santa Barbara ‘s anti-Vietnam activity impelled then-Gov. Ronald Reagan to impose a curfew and order the National Guard to enforce it. Armed guardsmen were a common sight on campus and in Isla Vista during this time.

    In 1995 The University of California-Santa Barbara was elected to the Association of American Universities– an organization of leading research universities with a membership consisting of 59 universities in the United States (both public and private) and two universities in Canada.

    On May 23, 2014 a killing spree occurred in Isla Vista, California, a community in close proximity to the campus. All six people killed during the rampage were students at The University of California-Santa Barbara. The murderer was a former Santa Barbara City College student who lived in Isla Vista.

    Research activity

    According to the National Science Foundation (US), The University of California-Santa Barbara spent $236.5 million on research and development in fiscal 2013, ranking it 87th in the nation.

    From 2005 to 2009 UCSB was ranked fourth in terms of relative citation impact in the U.S. (behind Massachusetts Institute of Technology (US), California Institute of Technology(US), and Princeton University (US)) according to Thomson Reuters.

    The University of California-Santa Barbara hosts 12 National Research Centers, including the Kavli Institute for Theoretical Physics, the National Center for Ecological Analysis and Synthesis, the Southern California Earthquake Center, the UCSB Center for Spatial Studies, an affiliate of the National Center for Geographic Information and Analysis, and the California Nanosystems Institute. Eight of these centers are supported by The National Science Foundation (US). UCSB is also home to Microsoft Station Q, a research group working on topological quantum computing where American mathematician and Fields Medalist Michael Freedman is the director.

    Research impact rankings

    The Times Higher Education World University Rankings ranked The University of California-Santa Barbara 48th worldwide for 2016–17, while the Academic Ranking of World Universities (ARWU) in 2016 ranked https://www.nsf.gov/ 42nd in the world; 28th in the nation; and in 2015 tied for 17th worldwide in engineering.

    In the United States National Research Council rankings of graduate programs, 10 University of California-Santa Barbara departments were ranked in the top ten in the country: Materials; Chemical Engineering; Computer Science; Electrical and Computer Engineering; Mechanical Engineering; Physics; Marine Science Institute; Geography; History; and Theater and Dance. Among U.S. university Materials Science and Engineering programs, The University of California-Santa Barbara was ranked first in each measure of a study by the National Research Council of the NAS.

    The Centre for Science and Technologies Studies at

     
  • 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., , Particle Physics, , , 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
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    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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    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.

     
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