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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 Accelerators, , 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.

    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.

    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 .

    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.


    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 (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.


    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.


    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.


    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.


    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.


    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.


    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 1:59 am on October 9, 2021 Permalink | Reply
    Tags: "FAU physicists control the flow of electron pulses through a nanostructure channel", APF: alternating phase focusing, , , DLA uses ultra-fast laser technology and advances in semi-conductor production to potentially minimise these accelerators to merely a few millimetres or centimetres in size., DLA: dielectric laser acceleration, , , Particle Accelerators, ,   

    From Friedrich-Alexander-Universität Erlangen-Nürnberg [FAU] (DE): “FAU physicists control the flow of electron pulses through a nanostructure channel” 

    From Friedrich-Alexander-Universität Erlangen-Nürnberg [FAU] (DE)

    September 23, 2021

    Chair for Laser Physics
    Dr. Roy Shiloh
    Tel.: 09131/85-27211

    Johannes Illmer M.Sc.
    Tel.: 09131/85-27211

    Prof. Dr. Peter Hommelhoff
    Tel.: 09131/85-27090

    Experimental setup in the laser laboratory. Picture: Maximilian Schlosser.

    Particle accelerators are essential tools in research areas such as biology, materials science and particle physics. Researchers are always looking for more powerful ways of accelerating particles to improve existing equipment and increase capacities for experiments. One such powerful technology is dielectric laser acceleration (DLA). In this approach, particles are accelerated in the optical near-field which is created when ultra-short laser pulses are focused on a nanophotonic structure. Using this method, researchers from the Chair of Laser Physics at FAU have succeeded in guiding electrons through a vacuum channel, an essential component of particle accelerators. The basic design of the photonic nanostructure channel was developed by cooperation partner The Technical University of Darmstadt [Technische Universität Darmstadt] (DE). They have now published their joint findings in the journal Nature.

    Staying focused

    As charged particles tend to move further away from each other as they spread, all accelerator technologies face the challenge of keeping the particles within the required spatial and time boundaries. As a result, particle accelerators can be up to ten kilometres long, and entail years of preparation and construction before they are ready for use, not to mention the major investments involved. Dielectric laser acceleration, or DLA uses ultra-fast laser technology and advances in semi-conductor production to potentially minimise these accelerators to merely a few millimetres or centimetres in size.

    A promising approach: Experiments have already demonstrated that DLA exceeds currently used technologies by at least 35 times. This means that the length of a potential accelerator could be reduced by the same factor. Until now, however, it was unclear whether these figures could be scaled up for longer and longer structures.

    A team of physicists led by Prof. Dr. Peter Hommelhoff from the Chair of Laser Physics at FAU has taken a major step forward towards adapting DLA for use in fully-functional accelerators. Their work is the first to set out a scheme which can be used to guide electron pulses over long distances.

    Technology is key

    The scheme, known as ‘alternating phase focusing’ (APF) is a method taken from the early days of accelerator theory. A fundamental law of physics means that focusing charged particles in all three dimensions at once – width, height and depth – is impossible. However, this can be avoided by alternately focusing the electrons in different dimensions. First of all, electrons are focused using a modulated laser beam, then they ‘drift’ through another short passage where no forces act on them, before they are finally accelerated, which allows them to be guided forward.

    In their experiment, the scientists from FAU and TU Darmstadt incorporated a colonnade of oval pillars with short gaps at regular intervals, resulting in repeating macro cells. Each macro cell either has a focusing or defocusing effect on the particles, depending on the delay between the incident laser, the electron, and the gap which creates the drifting section. This setup allows precise electron phase space control at the optical or femto-second ultra-timescale (a femto-second corresponds to a millionth of a billionth of a second). In the experiment, shining a laser on the structure shows an increase in the beam current through the structure. If a laser is not used, the electrons are not guided and gradually crash into the walls of the channel. ‘It’s very exciting,’ says FAU physicist Johannes Illmer, co-author of the publication. ‘By way of comparison, the large Hadron collider at CERN uses 23 of these cells in a 2450 metre long curve. Our nanostructure uses five similar-acting cells in just 80 micrometres.’

    When can we expect to see the first DLA accelerator?

    ‘The results are extremely significant, but for us it is really just an interim step,’ explains Dr. Roy Shiloh, ‘and our final goal is clear: we want to create a fully-functional accelerator – on a microchip.’

    See the full article here.


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Friedrich-Alexander-Universität Erlangen-Nürnberg, [FAU] (DE} is a public research university in the cities of Erlangen and Nuremberg in Bavaria, Germany. The name Friedrich–Alexander comes from the university’s first founder Friedrich, Margrave of Brandenburg-Bayreuth, and its benefactor Christian Frederick Charles Alexander, Margrave of Brandenburg-Ansbach.

    FAU is the second largest state university in the state of Bavaria. It has 5 faculties, 24 departments/schools, 25 clinical departments, 21 autonomous departments, 579 professors, 3,457 members of research staff and roughly 14,300 employees.

    In winter semester 2018/19 around 38,771 students (including 5,096 foreign students) enrolled in the university in 265 fields of study, with about 2/3 studying at the Erlangen campus and the remaining 1/3 at the Nuremberg campus. These statistics put FAU in the list of top 10 largest universities in Germany. In 2018, 7,390 students graduated from the university and 840 doctorates and 55 post-doctoral theses were registered. Moreover, FAU received 201 million Euro (2018) external funding in the same year, making it one of the strongest third-party funded universities in Germany.

    FAU is also a member of DFG (Deutsche Forschungsgemeinschaft) and the Top Industrial Managers for Europe network.

  • richardmitnick 8:42 pm on September 28, 2021 Permalink | Reply
    Tags: "LS2 report: The new LHC collimators", , , , , Particle Accelerators, , , Sixteen new collimators have been installed in the accelerator over the last three years in preparation not only for the accelerator’s next period of operation (Run 3) but above all for the HL-LHC.   

    From CERN (CH) ATLAS : “LS2 report: The new LHC collimators” 

    Iconic view of the European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire](CH)CERN ATLAS detector

    CERN ATLAS another view Image Claudia Marcelloni ATLAS CERN

    From CERN (CH) ATLAS

    28 September, 2021

    During LS2, 16 new collimators have been installed in the LHC ready for the next run and above all for the future HL-LHC.

    Installation of the passive collimator absorber TCAPM in IR7, which protects the magnets from the losses produced by the interaction between the LHC beam and the IR7 collimators. In the picture: Cristina Bahamonde Image: CERN.

    Upgrades of the LHC collimation system, which began during LS1, have continued during LS2. Sixteen new collimators have been installed in the accelerator over the last three years in preparation not only for the accelerator’s next period of operation (Run 3) but above all for the future High-Luminosity LHC (HL-LHC).

    The HL-LHC, which is due to be commissioned at the end of 2027, will improve on the current LHC’s performance thanks to a tenfold increase in its integrated luminosity, i.e. the number of collisions per surface unit, thereby increasing the number of collisions inside the experiments. To achieve this, the HL-LHC’s beams of particles will be more intense, which is not without its problems.

    Increasing the number of particles in circulation, and therefore the number of collisions, requires the LHC’s equipment protection systems to be reinforced. Particles that stray from their trajectory could hit sensitive components such as superconducting magnets and interfere with their operation. Protection is particularly crucial in the vicinity of the experiments and the areas of the LHC that are dedicated to beam collimation.

    That’s why the HL-LHC needs a more efficient collimation system. The collimators, which are installed in two areas of the LHC (at Points 3 and 7 of the ring) and around the four big experiments (ALICE, ATLAS, CMS and LHCb), are special devices equipped with jaws – movable blocks made of heavy-duty materials – that close around the beam to clean up the stray particles. The materials used for these jaws are capable of withstanding extreme pressure and temperatures as well as high levels of radiation. Some of the collimators have fixed apertures and are there to protect the magnets from radiation.

    During LS2, 16 new collimators of various types have been installed in the machine. Two TCLD (target collimator long dispersion suppressor) collimators were installed around the ALICE experiment in 2020. The majority of the new collimators was installed in Point 7, where most of the beam “cleaning” takes place. “We’ve installed no fewer than 14 colllimators around Point 7 during LS2. Some have replaced existing collimators to improve them, while others are new additions,” explains Stefano Redaelli, who heads up the collimation upgrade work package for the HL-LHC project. “I’d like to thank all the teams involved from the Accelerator and Technology sector (ATS) for their unfailing commitment – they’ve accomplished a remarkable feat!”

    Three types of collimators have been installed: four primary collimators (TCPPM – target collimator primary pick-up, metallic), eight secondary collimators (TCSPM – target collimator secondary pick-up, metallic) and two fixed-aperture passive absorbers. “The primary and secondary collimators, which were manufactured with contributions by international industrial partners, have a new design,” says Stefano Redaelli. “They are based on a molybdenum–graphite compound that, thanks to its low electrical resistivity, helps to improve the stability of the planned higher-intensity beams. The secondary collimators are also coated in 6 microns of pure molybdenum, which further reduces their electrical resistivity by a factor of 20.” What’s more, these new collimators are equipped with sensors that monitor the beam position to allow the position of the jaws to be adjusted.

    Two new crystal collimators, which were developed for operation with heavy ions, are also due to be installed at Point 7 at the end of this year. We’ll report back next year with more details and the results of the first tests with beam.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    CERN Courier (CH)

    Quantum Diaries

    European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire(CH) map

    CERN LHC underground tunnel and tube.

  • richardmitnick 9:59 am on September 2, 2021 Permalink | Reply
    Tags: "The Installation of the BRIL Luminometers: Preparing for a bright Run 3", , , BRIL: "Beam Radiation Instrumentation and Luminosity", , , It is crucial to measure the real-time rate of collisions at CMS in order to optimize both the trigger rates and the quality of the beams delivered by the Large Hadron Collider (LHC)., Once in their final position the BRIL detectors lay at the heart of the CMS detector ~1.8 m from the interaction point just outside the forward pixel tracking detector., One of the most significant design changes has been the implementation of a new active cooling circuit for BCM1F which is essential for a silicon-based detector., Particle Accelerators, , , The silicon sensors used for BCM1F were sourced from a batch currently being developed for the CMS Phase II upgrade for the High-Luminosity LHC., Three instruments: the Beam Condition Monitor “Fast” (BCM1F); Beam Condition Monitor for Losses (BCM1L); Pixel Luminosity Telescope (PLT)   

    From CERN (CH) CMS: “The Installation of the BRIL Luminometers-Preparing for a bright Run 3” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    From CERN (CH) CMS


    By Andrés G. Delannoy and Joanna Wanczyk, for the BRIL group

    After long months of preparations, the Beam Radiation Instrumentation and Luminosity (BRIL) group has completed the installation of three instruments dedicated to the measurement of luminosity and beam conditions: the Beam Condition Monitor “Fast” (BCM1F), the Beam Condition Monitor for Losses (BCM1L), and the Pixel Luminosity Telescope (PLT). All three of the BRIL subsystems represent a new “generation” in their respective design history. Both PLT and BCM1F implement the use of silicon sensors, while BCM1L uses poly-crystalline diamond sensors.

    Finalized BRIL subsystems, where the PLT is enclosed in the yellow structure with BCM1F directly behind it. Two green BCM1L modules are visible for the top left quadrant. Credits: A.G. Delannoy.

    It is crucial to measure the real-time rate of collisions at CMS in order to optimize both the trigger rates and the quality of the beams delivered by the Large Hadron Collider (LHC). Moreover, continuously assessing the beam conditions is essential to the protection of the LHC machine and sensitive CMS sub-detectors. And, of course, the aggregated luminosity measurements need to be meticulously understood to determine the expected frequency of each type of interaction in nearly every analysis performed on the data collected by the CMS experiment.

    All in all, the design and production of new components, sensor characterization, assembly, stress-testing under thermal cycles troubleshooting and repairs, etc. spanned a few years of challenging work, which ramped up as the Long Shutdown 2 came to a close and the installation date lurked around the corner. Finally, after finalizing all preparations, the transport activities began before sunrise of July 5th, 2021.

    Each half of the detector was carefully loaded onto a special transport vehicle and dry air was circulated inside their transport boxes. Only days before, each quarter of the detector had been delicately readied for its journey, which included labeling them with their affectionately selected aliases: Calabrese, Capricciosa, Diavola, and Margherita. The detector slowly made its way along the base of the Jura mountains until reaching the CMS site. The transport boxes containing the BRIL subsystems are relatively small, which allowed them to ride down in the elevator to the ground floor, 97m underground, to the CMS experimental cavern where they were subsequently craned up to the bulkhead platform.

    +Z side of the BRIL subsystems being craned onto the bulkhead platform. Credits: A.G. Delannoy.

    Once in their final position the BRIL detectors lay at the heart of the CMS detector ~1.8 m from the interaction point just outside the forward pixel tracking detector. The carbon-fiber structure that supports each detector quadrant has small wheels that guide it along purposely designed rails into its final location. After physically installing each of the detector quadrants, the cooling circuit, which provides active coolant to the PLT and BCM1F detectors, had to be tightly sealed using specialized metal o-rings.

    Joanna Wanczyk (left) and Rob Loos (right) install the +Z Far (Margherita) quadrant. Credits: A.G. Delannoy.

    One of the most significant design changes has been the implementation of a new active cooling circuit for BCM1F which is essential for a silicon-based detector. The PLT cooling loop has been modified to include an extension for BCM1F. The design of the BCM1F cooling circuit follows the approach implemented for the PLT during Run 2: the cooling structure is fabricated by 3D printing a titanium alloy using the selective laser melting technique.

    Furthermore, the silicon sensors used for BCM1F were sourced from a batch currently being developed for the CMS Phase II upgrade for the High-Luminosity LHC. The same is the case for three of the sensors used in one of the PLT channels. “This is the first time that these prototype Phase II silicon pixel sensors will be installed in CMS, so the whole community is eager to see how this material behaves,” says Anne Dabrowski, CMS BRIL project manager.

    Joanna Wanczyk (left) and Georg Auzinger (right) work on the -Z side bulkhead platform. Credits: A.G. Delannoy.

    BRIL Upgrade

    See the full article here.

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Meet CERN (CH) in a variety of places:

    Quantum Diaries

    Cern Courier (CH)

  • richardmitnick 11:29 am on August 31, 2021 Permalink | Reply
    Tags: "Photographing the HL-LHC" Photo Essay, , , , , , Particle Accelerators, , ,   

    From Symmetry: “Photographing the HL-LHC” Photo Essay 

    Symmetry Mag

    From Symmetry

    Samuel Hertzog

    A CERN photographer and videographer writes about his experiences documenting the ongoing upgrade that will turn the Large Hadron Collider into the High-Luminosity LHC.

    “It’s August 2019, and I’m a photographer employed by CERN to create audiovisual content for CERN’s internal and external communication. Today a colleague and I are photographing the ongoing civil engineering for new passages, caverns and shafts that will enlarge CERN’s subterranean accelerator complex. When completed, they will house the powering, protection and cryogenic systems for the High-Luminosity LHC. These upgrades will increase the collision rate by a factor of five beyond the LHC’s design value and enable the experiments to search for new physics and phenomena that were previously out of reach.

    A security officer guides us, making sure we stay out of the way of the heavy machinery while he shows us his favorite spots. The lighting is dim, which makes navigating the rocky and uneven pathway even more treacherous.

    Photo by Maximilien Brice.

    Courtesy of Samuel Hertzog and Jules Ordan.

    “Our mission is to collect photos and video footage that both convey the feel of the place and document the action. In just a short time, with limited recording gear and the addition of bulky gloves, boots, masks and protective glasses, we rush to set up our shots.

    Two things stand out: The scale of the place, and how rough an area it is. This, to a photographer, is a sign that it is time to break out the wide-angle lenses and get right up close to the workers. We want to create an immersive feeling for the viewer, a sense that they are right there with us taking in the entire scene.

    Courtesy of Samuel Hertzog and Jules Ordan.

    “Before coming to CERN in winter 2019, I primarily focused on wildlife photography and filmmaking. Working at CERN is unlike anything I’ve done before. I often say shooting the CERN caverns is where a top photographer can really make their mark. You are faced with huge structures but very little room to maneuver. It’s dark, so you need to hold for long exposures. But there are also lots of people and machines moving at all times. To balance all these factors at once is a real test of your skills.

    Toward the end of 2019, the workers break through the wall and connect the new tunnel to the one that holds the LHC. Project leaders and the Director General of CERN hold a ceremony to commemorate the moment. The heads of CERN dress in work suits and descend the shaky metallic steps to pose for a photo and sit for a short interview under bright lights we set up for the occasion. It feels almost like being in a photo studio 100 meters underground.

    Courtesy of Samuel Hertzog and Jules Ordan.

    “In May 2021—18 months after the subterranean photoshoot—we return to the HL-LHC tunnels. The crews have been working 24/7 to get the tunnel construction completed before the LHC restart in Spring 2022. We are told that dust is no longer the issue, but vertigo might be. The temporary elevator is being replaced, so our way down is essentially a large bucket suspended by a rope. No room for unsteady nerves on this site!

    Courtesy of Samuel Hertzog and Jules Ordan

    “When we reach the bottom, the tunnel is radically different. We find ourselves in a clean, white entrance hall, with our path illuminated at regular intervals by elegant blue lights.

    Courtesy of Samuel Hertzog and Jules Ordan.

    “The challenge is now less technically extreme. Creatively, however, this is a whole new game. We still have the heavy machinery and workers in high-vis uniforms. But otherwise, the surroundings are pure science fiction. We respond with a change in style, paying attention to symmetry, proportions and structure to convey the modern, elegant environment.

    Courtesy of Samuel Hertzog and Jules Ordan.

    “It is a photographer’s duty to be adaptable and quick to come up with new ideas when documenting, and CERN’s ever-changing environments certainly test those skills. Conditions and constraints ultimately bring out creativity. It is remarkable to me to look back and see not only the evolution the location but also of my own perspective.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 11:17 am on August 26, 2021 Permalink | Reply
    Tags: "Teaching a particle detector new tricks", , , , , , Particle Accelerators, , ,   

    From Symmetry: “Teaching a particle detector new tricks” 

    Symmetry Mag

    From Symmetry

    Sarah Charley

    Scientists hoping to find new, long-lived particles at the Large Hadron Collider recently realized they may already have the detector to do it.

    European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(EU) CMS Detector

    Physicist Cristián Peña grew up in Talca, a small town a few hours south of Santiago, Chile. “The Andes run all the way through the country,” he says. “No matter where you look, you always have the mountains.”

    At the age of 13, he first aspired to climb them.

    Over the years, as his mountaineering skills grew, so did his inventory of tools. Ice axes, crampons and ropes expanded his horizons.

    In Peña’s work as a scientist at the DOE’s Fermi National Accelerator Laboratory (US), he applies this same mindset: He creates the tools his experiment needs to explore new terrain.

    “Detector work is key,” he says.

    Peña’s current focus is the CMS detector, one of two large, general-purpose detectors at the Large Hadron Collider. Peña and colleagues want to use CMS to search for a class of theoretical particles with long lifetimes.

    While working through the problem, they realized that an ideal long-lived particle detector is already installed inside CMS: the CMS muon system. The question was whether they could hack it to do something new.

    Courtesy of CMS Collaboration.

    Long-lived particles

    When scientists designed the CMS detector in the 1990s, they had the most popular and mathematically resilient models of particle physics in mind. As far as they knew, the most interesting particles would live just a fraction of a fraction of a second before transforming into well understood secondary particles, such as photons and electrons. CMS would catch signals from those secondary particles and use them as a trail back to the original.

    The prompt-decay assumption worked in the search for Higgs bosons. But scientists are now realizing that this “live fast, die young” model might not apply to every interesting thing that comes out of a collision at the LHC. Peña says he sees this as a sign that it’s time for the experiment to evolve.

    “If you’re a little kid and you walk a mile in the forest, it’s all completely new,” he says. “Now we have more experience and want to push new frontiers.”

    For CMS scientists, that means finding better ways to look for particles with long lifetimes.

    Long-lived particles are not a radical new concept. Neutrons, for example, live for about 14 minutes outside the confines of an atomic nucleus. And protons are so long-lived that scientists aren’t sure whether they decay at all. If undiscovered particles are moving into the detector before becoming visible, they could be hiding in plain sight.

    “Previously, we hadn’t really thought to look for long-lived particles,” says Christina Wang, a graduate student at The California Institute of Technology (US) working on the CMS experiment. “Now, we have to find new ways to use the CMS detector to see them.”

    A new idea

    Peña was thinking about long-lived particles while attending a conference in Aspen, Colorado, in March 2019.

    “There were a bunch of whiteboards, and we were throwing around ideas,” he says. “In that type of situation, you go with the vibe. There’s a lot of creativity and you start thinking outside the box.”

    Peña and his colleagues visualized what an ideal long-lived particle detector might look like. They would need a detector that was far from the collision point. And they would need shielding to filter out the secondary particles that are the stars of the show in traditional searches.

    “When you look at the CMS muon system,” Peña says, “that’s exactly what it is.”

    Muons, often called the heavier cousins of electrons, are produced during the high-energy collisions inside the LHC. A muon can travel long distances, which is why CMS and its sister experiment, ATLAS, have massive detectors in their outer layers solely dedicated to capturing and recording muon tracks.

    Peña ran a quick simulation to see if the CMS muon system would be sensitive to the firework-like signatures of long-lived particles. “It was quick and dirty,” he says, “but it looked feasible.”

    After the conference, Peña returned to his regular activities. A few months later, Caltech rising sophomore Nathan Suri joined Professor Maria Spiropulu’s lab as a summer student, working with Wang. Peña, who was also collaborating with Spiropulu’s research group, assigned Suri the muon detector idea as his summer project.

    “I was always encouraged to give ideas to young, talented people and let them run with it,” Peña says.

    Suri was excited to take on the challenge. “I was in love with the originality of the project,” he says. “I was eager to sink my teeth into it.”

    Testing the concept

    Suri started by scanning event displays of simulated long-lived particle decays to look for any shared visual patterns. He then explored the original technical design report for the CMS muon detector system to see just how sensitive it could be to these patterns.

    “Looking at the unique detector design and highly sensitive elements, I was able to realize what a powerful tool it was,” he says.

    By the end of the summer, Suri’s work had shown that not only was it feasible to use the muon system to detect long-lived particles, but that CMS scientists could use pre-existing LHC data to get a jump start on the search.

    “At this point, the floodgates opened,” Suri says.

    In fall 2019, Wang took the lead on the project. Suri had shown that the idea was possible; Wang wanted to know if it was realistic.

    So far, they had been working with processed data from the muon system, which was not adapted to the kind of search they wanted to do. “All the reconstruction techniques used in the muon system are optimized to detect muons,” Wang says.

    Wang, Peña and Caltech Professor Si Xie set-up a Zoom meeting with muon system experts to ask for advice.

    “They were really surprised that we wanted to use the muon system to infer long-lived particles,” Wang says. “They were like, ‘It’s not designed to do that.’ They thought it was a weird idea.”

    The experts suggested the team should try looking at the raw data instead.

    Doing so would require extracting unprocessed information from tapes and then developing new software and simulations that could reinterpret thousands of raw detector hits. The task would be arduous, if not impossible.

    After the muon system experts left the call, Wang remembers, “we were still in the Zoom room and like, ‘Do we want to continue this?’”

    She says it was not a serious question. Of course they did.

    A trigger of their own

    In fall 2020, Martin Kwok started a postdoctoral position at Fermilab. “We’re encouraged to talk to as many groups as we can and think about what we want to work on most,” he says.

    He met with Fermilab researcher Artur Apresyan, who told him about the collaboration with Caltech to convert the CMS muon system into a long-lived particle detector. “It was immediately attractive,” Kwok says. “It’s not very often that we get to explore new uses for our detector.”

    Wang and her colleagues had forged ahead with the idea, extracting, processing, and analyzing raw data recorded by the CMS muon system between 2016 and 2018.

    It had worked, but the dataset they had available to study was not ideal.

    The LHC generates around a billion collisions every second—much more than scientists can record and process. So scientists use filters called triggers to quickly evaluate and sort fresh collision data.

    For every billion collisions, only about 1000 are deemed “interesting” by the triggers and saved for further analysis. Wang and her colleagues had determined the filters closest to what they were looking for were the ones programmed to look for signs of dark matter.

    Apresyan pitched to Kwok that he could design a new trigger, one actually meant to look for signs of long-lived particles. They could install it in the CMS muon system before the LHC restarts operation in spring 2022.

    With a dedicated trigger, they could increase the number of events deemed “interesting” for long-lived particle searches by up to a factor of 30. “It’s not often that we see a 30-times increase in our ability to capture potential signal events,” Kwok says.

    Kwok was up for the challenge. And it was a challenge.

    “The price of doing something different—of doing something innovative—is that you have to invent your own tools,” Kwok says.

    The CMS collaboration consists of thousands of scientists all using collective research tools that they developed and honed over the last two decades. “It’s a bit like building with Legos,” Kwok says. “All the pieces are there, and depending on how you use and combine them, you can make almost anything.”

    But developing this specialized trigger was less like picking the right Legos and more like creating a new Lego piece out of melted plastic.

    Kwok dug into the experiment’s archives in search of his raw materials. He found an old piece of software that had been developed by CMS but rarely used. “This left-over tool that faded out of popularity turned out to be very handy,” he says.

    Kwok and his collaborators also had to investigate if integrating a new trigger into the muon system was even possible. “There’s only so much bandwidth in the electronics to send information upstream,” Kwok says.

    “I’m thankful that our collaboration ancestors designed the CMS muon system with a few unused bits. Otherwise, we would have had to reinvent the whole triggering scheme.”

    What started as a feasibility study has now evolved into an international effort, with many more institutions contributing to data analysis and trigger R&D. The US institutions contributing to this research are funded by the Department of Energy (US) and the National Science Foundation (US).

    “Because we don’t have dedicated long-lived particle triggers yet, we have a low efficiency,” Wang says. “But we showed that it’s possible—and not only possible, but we are overhauling the CMS trigger system to further improve the sensitivity.”

    The LHC is scheduled to continue into the 2030s, with several major accelerator and detector upgrades along the way. Wang says that to keep probing nature at its most fundamental level, scientists must remain at the frontier of detector technology and question every assumption.

    “Then new areas to explore will naturally follow,” she says. “Long-lived particles are just one of these new areas. We’re just getting started.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 8:30 pm on August 24, 2021 Permalink | Reply
    Tags: "Can light melt atoms into goo?", , , Brookhaven National Laboratory (US) Relativistic Heavy Ion Collider, , , Particle Accelerators, , , , ,   

    From Symmetry: “Can light melt atoms into goo?” 

    Symmetry Mag

    From Symmetry

    Sarah Charley

    Courtesy of Christopher Plumberg

    The ATLAS experiment [CH] at European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN]. sees possible evidence of quark-gluon plasma production during collisions between photons and heavy nuclei inside the Large Hadron Collider.

    Photons—the massless particles also known as the quanta of light—are having a moment in physics research.

    Scientists at the Large Hadron Collider have recently studied how, imbued with enough energy, photons can bounce off of one another like massive particles do. Scientists at the LHC and the DOE’s Brookhaven National Laboratory (US) Relative Heavy Ion Collider (US) have also reported seeing photons colliding and converting that energy into massive particles.

    The photon’s most recent seemingly impossible feat? Smashing so hard into a lead nucleus that the collision seems to produce the same state of matter that existed moments after the Big Bang.

    Simulated quark-gluon plasma formation. Courtesy of Chistopher Plumberg.

    “I did not expect that photons could produce a quark-gluon plasma until I actually saw the results,” says theoretical nuclear physicist Jacquelyn Noronha-Hostler, an assistant professor at the University of Illinois -Urbana-Champaign (US).

    Scientists at the LHC at CERN and at RHIC at DOE’s Brookhaven National Laboratory (US) have known for years they could produce small amounts of quark-gluon plasma in collisions between heavy ions. But this is the first time scientists have reported possible evidence of quark-gluon plasma in the aftermath of a collision between the nucleus of a heavy ion and a massless particle of light.

    The scenario seems unlikely. Unlikely, but not impossible, says ATLAS physicist Dennis Perepelitsa, who is an assistant professor at The University of Colorado-Boulder (US).

    “In quantum mechanics, everything that is not forbidden is compulsory,” Perepelitsa says. “If it can happen, it will happen. The question is just how often.”

    Collisions between photons and lead nuclei are common inside the LHC. Perepelitsa and his colleagues are the first to examine them to find out whether they ever produce a quark-gluon plasma. Their first round of results indicate the answer could be yes, an insight that might provide a new understanding of fluid dynamics.

    Scientists contributing to LHC research from US institutions are funded by the Department of Energy (US) and the National Science Foundation (US).

    The Large Light Collider

    Perepelitsa and his colleagues on the ATLAS experiment went looking for collisions between photons and nuclei, called photonuclear collisions, in data collected during the lead-ion runs at the LHC. These runs have happened in the few weeks just before the LHC’s winter shutdown each year that the LHC has been in operation.

    Lead nuclei are made up of protons and neutrons, which are made up of even smaller fundamental particles called quarks. “You can think of the nucleus like a bag of quarks,” Noronha-Hostler says.

    This bag of quarks is held together by gluons, which “glue” small groups of quarks into composite particles called hadrons.

    When two lead nuclei collide at high energy inside the LHC, the gluons can lose their grip, causing the protons and neutrons to melt and merge into a quark-gluon plasma. The now-free quarks and gluons pull on each other, holding together as the plasma expands and cools.

    Eventually, the quarks cool enough to reform into distinct hadrons. Scientists can reconstruct the production, size and shape of the original quark-gluon plasma based on the number, identities and paths of hadrons that escape into their detectors.

    During the lead-ion runs at the LHC, nuclei aren’t the only things colliding. Because they have a positive charge, lead nuclei carry strong electromagnetic fields that grow in intensity as they accelerate. Their electromagnetic fields spit out high-energy photons, which can also collide—a fairly common occurence. “There’s a lot of photons, and the nucleus is big,” Perepelitsa says.

    Despite their frequency, no one had ever closely examined the detailed patterns of these kinds of photonuclear collisions at the LHC. For this reason, ATLAS scientists had to develop a specialized trigger that could pick out the photon-zapped lead ions from everything else.

    According to Blair Seidlitz, a graduate student at CU Boulder, this was tricky. “People have a lot more experience triggering on lead-lead collisions,” he says.

    Luckily, photonuclear collisions have a special asymmetrical shape due to the momentum differences between the tiny photon and the massive lead ion: “It’s like a truck hitting a trash can,” Seidlitz says. “All the debris from the collision will move in the direction of the truck.”

    Seidlitz designed a trigger that looked for collisions that generated a small number of particles, had a skewed shape, and saw remnants of the partially obliterated lead ion embedded in special detectors 140 meters away from the collision point.

    After collecting and analyzing the data, Seidlitz, Perepelitsa and their colleagues saw a particle-flow signature characteristic of a quark-gluon plasma.

    The finding alone is not enough to prove the formation of a quark-gluon plasma, but it’s a first clue. “There are always potential competing explanations, and we need to look for other signatures of quark-gluon plasma that could be there,” Perepelitsa says, “but we haven’t measured them yet.”

    If the photonuclear collisions are indeed creating quark-gluon plasma, it could be a kind of quantum trick, Perepelitsa says.

    Perepelitsa and his colleagues are dubious that a massless photon could pack a powerful enough punch to melt part of a lead nucleus, which contains 82 protons and 126 neutrons. “It would be like throwing a needle into a bowling ball,” he says.

    Instead, he thinks that just before impact, these photons are undergoing a transformation originally predicted by Nobel Laureate Paul Dirac.

    A quantum transformation

    In 1931, Dirac published a paper predicting a new type of particle. The particle would share the mass of the electron but have the opposite charge [positron]. Also, he predicted, “if it collides with an electron, the two will have a chance of annihilating one another.”

    It was the positron, the first predicted particle of antimatter. In 1932, The California Institute of Technology (US) physicist Carl Anderson discovered the particle, and later physicists spotted the annihilation process Dirac had predicted as well.

    When matter and antimatter meet, the two particles are destroyed, releasing their energy in the form of a pair of photons.

    Scientists also see this process happening in reverse, Noronha-Hostler says. “Two photons can interact and create a quark-antiquark pair.”

    Before annihilating, that quark-antiquark pair can bind together to make a hadron.

    Perepelitsa and his colleagues suspect that the collisions they’ve observed, in which photons appear to be colliding with lead nuclei and creating a small amount of quark-gluon plasma, are not actually collisions between nuclei and photons. Instead, they’re collisions between nuclei and those tiny, ephemeral hadrons.

    This makes more sense, Perepelitsa says, as hadrons are bigger in size than photons and are capable of more substantial interactions. “It’s no longer a needle going into a bowling ball, but more like a bullet.”

    The smallest drop

    For now, the exact mechanism that may be causing this quark-gluon plasma signature within photonuclear collisions remains a mystery. Whatever is going on, Noronha-Hostler says figuring out these collisions could be an important step in quark-gluon plasma research.

    LHC scientists’ usual method of studying the quark-gluon plasma has been to examine crashes between lead nuclei, which create a complex soup of quarks and gluons. “We thought originally that the only way we could produce a quark gluon plasma was two massive nuclei hitting each other,” she says. “And then experimentalists started playing around and running smaller things, like protons. With photonuclear collisions, that’s even smaller.”

    If photonuclear collisions are creating quark-gluon plasma, it’s in the form of a tiny droplet composed of a few vaporized protons and neutrons.

    Scientists are hoping to study these droplets to learn more about how liquids behave on subatomic scales.

    “We’re pushing to the most extremes in fluid dynamics,” Noronha-Hostler says. “Not only do we have something that is moving at the speed of light and at the highest temperatures known to humanity, but it looks like we are going to be able to answer ‘What is the smallest droplet of a liquid?’ No other field can do that.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 10:47 am on August 19, 2021 Permalink | Reply
    Tags: , , , CERN COMPASS experiment, , , Particle Accelerators, , , Representation of the triangle singularity,   

    From The University of Bonn [Rheinische Friedrich-Wilhelms-Universität Bonn] (DE): “Transformation in the particle zoo” 

    From The University of Bonn [Rheinische Friedrich-Wilhelms-Universität Bonn] (DE)

    18. August 2021

    Prof. Dr. Bernhard Ketzer
    Helmholtz Institute for Radiation and Nuclear Physics [Helmholtz Institut für Strahlen und Kernphysik](DE) Bonn
    Tel.: +49 228/73-2539 (Büro)
    oder +49 228/73-2203 (Sekretariat)

    Study led by the University of Bonn finds evidence of a long-sought effect in CERN data.

    An international study led by the University of Bonn has found evidence of a long-sought effect in accelerator data. The so-called “triangle singularity” describes how particles can change their identities by exchanging quarks, thereby mimicking a new particle. The mechanism also provides new insights into a mystery that has long puzzled particle physicists: Protons, neutrons and many other particles are much heavier than one would expect. This is due to peculiarities of the strong interaction that holds the quarks together. The triangle singularity could help to better understand these properties. The publication is now available in Physical Review Letters.

    Representation of the triangle singularity: – The particle a1 produced in the collision decays into two particles K* and K-quer. These interact with each other to produce the two particles pi and f0. © Bernhard Ketzer/Uni Bonn.

    In their study, the researchers analyzed data from the COMPASS experiment at the European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN]. in Geneva. There, certain particles called pions are brought to extremely high velocities and shot at hydrogen atoms.

    Pions consist of two building blocks, a quark and an anti-quark. These are held together by the strong interaction, much like two magnets whose poles attract each other. When magnets are moved away from each other, the attraction between them decreases successively. With the strong interaction it is different: It increases in line with the distance, similar to the tensile force of a stretching rubber band.

    However, the impact of the pion on the hydrogen nucleus is so strong that this rubber band breaks. The “stretching energy” stored in it is released all at once. “This is converted into matter, which creates new particles,” explains Prof. Dr. Bernhard Ketzer of the Helmholtz Institute for Radiation and Nuclear Physics at the University of Bonn. “Experiments like these therefore provide us with important information about the strong interaction.”

    Unusual signal

    In 2015, COMPASS detectors registered an unusual signal after such a crash test. It seemed to indicate that the collision had created an exotic new particle for a few fractions of a second. “Particles normally consist either of three quarks – this includes the protons and neutrons, for example – or, like the pions, of one quark and one antiquark,” says Ketzer. “This new short-lived intermediate state, however, appeared to consist of four quarks.”

    Together with his research group and colleagues at the Technical University of Munich, the physicist has now put the data through a new analysis. “We were able to show that the signal can also be explained in a different way, that is, by the aforementioned triangle singularity,” he stresses. This mechanism was postulated as early as the 1950s by the Russian physicist Lev Davidovich Landau, but has not yet been proven directly.

    According to this, the particle collision did not produce a tetraquark at all, but a completely normal quark-antiquark intermediate. This, however, disintegrated again straight away, but in an unusual manner: “The particles involved exchanged quarks and changed their identities in the process,” says Ketzer, who is also a member of the Transdisciplinary Research Area “Building Blocks of Matter and Fundamental Interactions” (TRA Matter). “The resulting signal then looks exactly like that from a tetraquark with a different mass.” This is the first time such a triangle singularity has been detected directly mimicking a new particle in this mass range. The result is also interesting because it allows new insights into the nature of the strong interaction.

    Only a small fraction of the proton mass can be explained by Higgs mechanism

    Protons, neutrons, pions and other particles (called hadrons) have mass. They get this from the so-called Higgs mechanism, but obviously not exclusively: A proton has about 20 times more mass than can be explained by the Higgs mechanism alone. “The much bigger part of the mass of hadrons is due to the strong interaction,” Ketzer explains. “Exactly how the masses of hadrons come about, however, is not yet clear. Our data help us to better understand the properties of the strong interaction, and perhaps the ways in which it contributes to the mass of particles.”

    See the full article here.


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Bonn [Rheinische Friedrich-Wilhelms-Universität Bonn] (DE) is a public research university located in Bonn, North Rhine-Westphalia, Germany. It was founded in its present form as the Rhein-Universität (English: Rhine University) on 18 October 1818 by Frederick William III, as the linear successor of the Kurkölnische Akademie Bonn (English: Academy of the Prince-elector of Cologne) which was founded in 1777. The University of Bonn offers many undergraduate and graduate programs in a range of subjects and has 544 professors. Its library holds more than five million volumes.

    As of October 2020, among its notable alumni, faculty and researchers are 11 Nobel Laureates, 4 Fields Medalists, 12 Gottfried Wilhelm Leibniz Prize winners as well as some of the most gifted minds in Natural science, e.g. August Kekulé, Heinrich Hertz and Justus von Liebig; Major philosophers, such as Friedrich Nietzsche, Karl Marx and Jürgen Habermas; Famous German poets and writers, for example Heinrich Heine, Paul Heyse and Thomas Mann; Painters, like Max Ernst; Political theorists, for instance Carl Schmitt and Otto Kirchheimer; Statesmen, viz. Konrad Adenauer and Robert Schuman; famous economists, like Walter Eucken, Ferdinand Tönnies and Joseph Schumpeter; and furthermore Prince Albert, Pope Benedict XVI and Wilhelm II.

    The University of Bonn has been conferred the title of “University of Excellence” under the German Universities Excellence Initiative.

  • richardmitnick 3:20 pm on August 16, 2021 Permalink | Reply
    Tags: "Table-top electron camera catches ultrafast dynamics of matter", , , , Electron diffraction is one way to investigate the inner structure of matter., , , Particle Accelerators, , , Terahertz radiation, The accelerator components-here a bunch compressor-can be a hundred times smaller., The scientists fired bunches with roughly 10000 electrons each at a silicon crystal that was heated by a short laser pulse., The system is perfectly synchronised since it is using just one laser for all steps: generating; manipulating; measuring; and compressing the electron bunches., Typically ultrafast electron diffraction (UED) uses bunch lengths-or exposure times-of some 100 femtoseconds which is 0.1 trillionths of a second.   

    From DESY German Electron Synchrotron [Deütsches Elektronen-Synchrotron] (DE) : “Table-top electron camera catches ultrafast dynamics of matter” 

    From DESY German Electron Synchrotron [Deütsches Elektronen-Synchrotron] (DE)


    DESY team demonstrates first Terahertz enhanced electron diffractometer.
    Scientists at DESY have built a compact electron camera that can capture the inner, ultrafast dynamics of matter. The system shoots short bunches of electrons at a sample to take snapshots of its current inner structure and is the first such electron diffractometer that uses Terahertz radiation for pulse compression. The developer team around DESY scientists Dongfang Zhang and Franz Kärtner from the CFEL Center for Free-Electron Laser Science [Zentrum für Freie-Elektronen-Laserwissenschaft] (DE) validated their Terahertz-enhanced ultrafast electron diffractometer with the investigation of a silicon sample and present their work in the first issue of the journal Ultrafast Science, a new title in the Science group of scientific journals.

    The system fits on a lab table. It is adjusted with the help of an optical laser (green). Credit: DESY, Timm Rohwer.

    Electron diffraction is one way to investigate the inner structure of matter. However, it does not image the structure directly. Instead, when the electrons hit or traverse a solid sample, they are deflected in a systematic way by the electrons in the solid’s inner lattice. From the pattern of this diffraction, recorded on a detector, the internal lattice structure of the solid can be calculated. To detect dynamic changes in this inner structure, short bunches of sufficiently bright electrons have to be used. “The shorter the bunch, the faster the exposure time,” says Zhang, who is now a professor at Shanghai Jiao Tong University [海交通大学](CN). “Typically ultrafast electron diffraction (UED) uses bunch lengths-or exposure times-of some 100 femtoseconds which is 0.1 trillionths of a second.”

    Such short electron bunches can be routinely produced with high quality by state-of-the-art particle accelerators. However, these machines are often large and bulky, partly due to the radio frequency radiation used to power them, which operates in the Gigahertz band. The wavelength of the radiation sets the size for the whole device. The DESY team is now using Terahertz radiation instead with roughly a hundred times shorter wavelengths. “This basically means, the accelerator components-here a bunch compressor-can be a hundred times smaller, too,” explains Kärtner, who is also a professor and a member of the cluster of excellence “CUI: Advanced Imaging of Matter“ at the University of Hamburg [Universität Hamburg](DE).

    Schematic set-up of the Terahertz Ultrafast Electron Diffractometer. Credit: DESY, Dongfang Zhang.

    For their proof-of-principle study, the scientists fired bunches with roughly 10,000 electrons each at a silicon crystal that was heated by a short laser pulse. The bunches were about 180 femtoseconds long and show clearly how the crystal lattice of the silicon sample quickly expands within a picosecond (trillionths of a second) after the laser hits the crystal. “The behaviour of silicon under these circumstances is very well known, and our measurements fit the expectation perfectly, validating our Terahertz device,” says Zhang. He estimates that in an optimised set-up, the electron bunches can be compressed to significantly less than 100 femtoseconds, allowing even faster snapshots.

    On top of its reduced size, the Terahertz electron diffractometer has another advantage that might be even more important to researchers: “Our system is perfectly synchronised since we are using just one laser for all steps: generating; manipulating; measuring; and compressing the electron bunches, producing the Terahertz radiation and even heating the sample,” Kärtner explains. Synchronisation is key in this kind of ultrafast experiments. To monitor the swift structural changes within a sample of matter like silicon, researchers usually repeat the experiment many times while delaying the measuring pulse a little more each time. The more accurate this delay can be adjusted, the better the result. Usually, there needs to be some kind of synchronisation between the exciting laser pulse that starts the experiment and the measuring pulse, in this case the electron bunch. If both, the start of the experiment and the electron bunch and its manipulation are triggered by the same laser, the synchronisation is intrinsically given.

    In a next step, the scientists plan to increase the energy of the electrons. Higher energy means the electrons can penetrate thicker samples. The prototype set-up used rather low-energy electrons and the silicon sample had to be sliced down to a thickness of just 35 nanometres (millionths of a millimetre). Adding another acceleration stage could give the electrons enough energy to penetrate 30 times thicker samples with a thickness of up to 1 micrometre (thousandth of a millimetre), as the researchers explain. For even thicker samples, X-rays are normally used. While X-ray diffraction is a well established and hugely successful technique, electrons usually do not damage the sample as quickly as X-rays do. “The energy deposited is much lower when using electrons,“ explains Zhang. This could prove useful when investigating delicate materials.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition


    DESY German Electron Synchrotron [Deütsches Elektronen-Synchrotron] (DE) is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.


  • richardmitnick 8:07 pm on August 12, 2021 Permalink | Reply
    Tags: "SPS experiments are back in action", , , , , Particle Accelerators, ,   

    From European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN]: “SPS experiments are back in action” 

    Cern New Bloc

    Cern New Particle Event

    From European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN]

    12 August, 2021
    Ana Lopes

    The Super Proton Synchrotron (SPS) lives up to its superlative designation. It’s CERN’s second-largest accelerator and is the last link in the accelerator chain that feeds particle beams to the Large Hadron Collider (LHC). What’s more, it supplies beams to a range of non-LHC experiments that address an impressive array of topics, from precision tests of the Standard Model of particle physics to studies of the quark–gluon plasma, a state of matter believed to have existed shortly after the Big Bang.

    Following hot on the heels of the restart of the Proton Synchrotron Booster and the Proton Synchrotron after the second long shutdown of CERN’s accelerator complex, the SPS and its experiments are now also back in action.

    The SPS delivers particle beams to all of CERN’s North Area (NA) experiments, to the associated test beam areas, as well as to the AWAKE experiment [below], which investigates the use of a wakefield created by protons zipping through a plasma to accelerate charged particles, and to the HiRadMat facility, which tests materials and accelerator components in extreme conditions.

    The NA experiments are an essential strand of the Laboratory’s experimental programme. NA58/COMPASS [below] studies how quarks and gluons form composite particles such as protons and pions. NA61/SHINE investigates the quark–gluon plasma and takes particle measurements for neutrino and cosmic-ray experiments. NA62 studies rare kaon decays and searches for new heavy neutral leptons. NA63 [below] investigates radiation processes in strong electromagnetic fields. NA64 searches for new particles that could carry a new force between visible matter and dark matter, or that could make up dark matter themselves. Last but not least, NA65, a new experiment that was approved in 2019, will take measurements of tau neutrinos for neutrino experiments and for tests of the Standard Model.

    NA62 has just restarted taking data for physics studies, and the remaining experiments will start doing so in the coming weeks and months. Highlights include the start of NA65 in September and the first pilot runs in October for experiments proposed in the Physics Beyond Colliders initiative, such as AMBER (the successor of COMPASS) and NA64m (NA64 running with beams of muons).

    “It’s always a thrill to witness the restart of the experiments, as is to see the fresh data that they deliver, not least after the extensive upgrades they have undergone over the past two years,” says Johannes Bernhard, the leader of the Liaison to Experiments section at CERN. “And if the past seasons of data-taking are any indication, there will be plenty of new physics results to digest and to direct future studies.”

    See the full article here.

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries

    Cern Courier








    European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(EU)[CERN] AEGIS.

    CERN FASER is designed to study the interactions of high-energy neutrinos and search for new as-yet-undiscovered light and weakly interacting particles. Such particles are dominantly produced along the beam collision axis and may be long-lived particles, travelling hundreds of metres before decaying. The existence of such new particles is predicted by many models beyond the Standard Model that attempt to solve some of the biggest puzzles in physics, such as the nature of dark matter and the origin of neutrino masses.

    CERN The SPS’s new RF system. Image: CERN

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