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  • richardmitnick 5:18 pm on December 18, 2021 Permalink | Reply
    Tags: , , , , CERN CH CMS, , , , , , , Triggers   

    From Symmetry: “Blink and it’s gone” 

    Symmetry Mag

    From Symmetry

    07/13/21 [Found in a year-end round up]
    Eoin O’Carroll

    Fast electronics and artificial intelligence are helping physicists capture data and decide what to keep and what to throw away.

    Illustration by Sandbox Studio, Chicago with Ana Kova.

    The nucleus of the atom was discovered a century ago thanks to scientists who didn’t blink.

    Working in pitch darkness at The University of Manchester (UK) between 1909 and 1913, research assistants Hans Geiger and Ernest Marsden peered through microscopes to count flashes of alpha particles on a fluorescent screen. The task demanded total concentration, and the scientists could count accurately for only about a minute before fatigue set in. The physicist and science historian Siegmund Brandt wrote that Geiger and Marsden maintained their focus by ingesting strong coffee and “a pinch of strychnine.”

    Modern particle detectors use sensitive electronics instead of microscopes and rat poison to observe particle collisions, but now there’s a new challenge. Instead of worrying about blinking and missing interesting particle interactions, physicists worry about accidentally throwing them away.

    The Large Hadron Collider at CERN produces collisions at a rate of 40 million per second, producing enough data to fill more than 140,000 one-terabyte storage drives every hour.

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

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

    CERN LHC tunnel and tube.

    SixTRack CERN LHC particles.

    Capturing all those events is impossible, so the electronics have to make some tough choices.

    To decide which collisions to retain for analysis and which ones to discard, physicists use specialized systems called trigger systems. The trigger is the only component to observe every collision. In about half the time it takes a human to blink, the CMS experiment’s triggers have processed and discarded 99.9975% of the data.

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

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

    Depending on how a trigger is programmed, it could be the first to capture evidence of new phenomena—or to lose it.

    “Once we lose the data, we lose it forever,” says Georgia Karagiorgi, a professor of physics at Columbia University (US) and the US project manager for the data acquisition system for the Deep Underground Neutrino Experiment. “We need to be constantly looking. We can’t close our eyes.”

    The challenge of deciding in a split second which data to keep, some scientists say, could be met with artificial intelligence.

    A numbers game

    Discovering new subatomic phenomena often requires amassing a colossal dataset, most of it uninteresting.

    Geiger and Marsden learned this the hard way. Working under the direction of Ernest Rutherford, the two scientists sought to reveal the structures of atoms by sending streams of alpha particles through sheets of gold foil and observing how the particles scattered. They found that for about every 8000 particles that passed straight through the foil, one particle would bounce away as though it had collided with something solid. That was the atom’s nucleus, and its discovery sent physics itself on a new trajectory.

    By today’s physics’ standards, Geiger and Marsden’s 1-in-8000 odds look like a safe bet. The Higgs boson is thought to appear in only one out of every 5 billion collisions in the LHC.

    European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) CMS Higgs Event May 27, 2012.

    European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) ATLAS Higgs Event

    The triggers will soon need to get even faster. In the LHC’s Run 3, set to begin in March 2022, the total number of collisions will equal that of the two previous runs combined. The collision rate will increase dramatically during the LHC’s High-Luminosity era, which is scheduled to begin in 2027 and continue through the 2030s. That’s when the collider’s luminosity, a measure of how tightly the crossing beams are packed with particles, is set to increase tenfold over its original design value.

    Collecting this data is important because in the coming decade, scientists will intensify their searches for phenomena that are just as mysterious to today’s physicists as atomic nuclei were to Geiger and Marsden.

    And scientists have only a small window of time in which to catch them.

    “At CMS we have a massive amount of data,” says Princeton University (US) physicist Isobel Ojalvo, who has been heavily involved in upgrading the CMS trigger system. “We’re only able to store that data for about three and a half [millionths of a second] before we make decisions about keeping it or throwing it away.”

    A new physics

    In 2012, the Higgs boson became the last confirmed elementary particle of the Standard Model, the equation that succinctly describes all known forms of matter and predicts with astonishing accuracy how they interact.

    Standard Model of Particle Physics, Quantum Diaries

    But there are strong signs that the Standard Model, which has guided physics for nearly 50 years, won’t have the last word. In April, for instance, preliminary results from the Muon g-2 experiment at The DOE’s Fermi National Accelerator Laboratory (US) offered tantalizing hints that the muon may be interacting with a force or particle the Standard Model doesn’t include.

    DOE’s Fermi National Accelerator Laboratory(US) Muon g-2 studio. As muons race around a ring at the Muon g-2 studio, their spin axes twirl, reflecting the influence of unseen particles.

    Identifying these phenomena and many others may require a new understanding.

    “Given that we have not seen [beyond the Standard Model] physics yet, we need to revolutionize how we collect our data to enable processing data rates at least an order of magnitude higher than achieved thus far,” says The Massachusetts Institute of Technology (US) physicist Mike Williams, who is a member of the Institute for Research and Innovation in Software for High-Energy Physics, IRIS-HEP, funded by the National Science Foundation.

    Physicists agree that future triggers will need to be faster, but there’s less consensus on how they should be programmed.

    “How do we make discoveries when we don’t know what to look for?” asks Peter Elmer, executive director and principal investigator for IRIS-HEP. “We don’t want to throw anything away that might hint at new physics.”

    There are two different schools of thought, Ojalvo says.

    The more conservative approach is to search for signatures that match theoretical predictions. “Another way,” she says, “is to look for things that are different from everything else.”

    This second option, known as anomaly detection, would scan not for specific signatures, but for anything that deviates from the Standard Model, something that artificial intelligence could help with.

    “In the past, we guessed the model and used the trigger system to pick those signatures up,” Ojalvo says.

    But “now we’re not finding the new physics that we believe is out there,” Ojalvo says. “It may be that we cannot create those interactions in present-day colliders, but we also need to ask ourselves if we’ve turned over every stone.”

    Instead of searching one-by-one for signals predicted by each theory, physicists could deploy to a collider’s trigger system an unsupervised machine-learning algorithm, Ojalvo says. They could train the algorithm only on the collisions it observes, without reference to any other dataset. Over time, the algorithm would learn to distinguish common collision events from rare ones. The approach would not require knowing any details in advance about what new signals might be, and it would avoid bias toward one theory or another.

    MIT physicist Philip Harris says that recent advances in artificial intelligence are fueling a growing interest in this approach—but that advocates of “theoryless searches” remain a minority in the physics community.

    More generally, says Harris, using AI for triggers can create opportunities for more innovative ways to acquire data. “The algorithm will be able to recognize the beam conditions and adapt their choices,” he says. “Effectively, it can change itself.”

    Programming triggers calls for tradeoffs between efficiency, breadth, accuracy and feasibility. “All of this is wonderful in theory,” says Karagiorgi. “It’s all about hardware resource constraints, power resource constraints, and, of course, cost.”

    “Thankfully,” she adds, “we don’t need strychnine.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 2:47 pm on December 15, 2021 Permalink | Reply
    Tags: "What’s next at the Large Hadron Collider? UB physicists are prepping for its new run", , , CERN CH CMS, , , , ,   

    From The University at Buffalo-SUNY (US): “What’s next at the Large Hadron Collider? UB physicists are prepping for its new run” 

    SUNY Buffalo

    From The University at Buffalo-SUNY (US)

    December 14, 2021
    Charlotte Hsu
    News Content Manager
    Sciences, Economic Development
    Tel: 716-645-4655

    Photo illustration: Left to right: University at Buffalo physicists Avto Kharchilava, Ia Iashvili and Salvatore Rappoccio. Credit: Douglas Levere / University at Buffalo / European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire](CH).

    University at Buffalo physicists have received $1.65 million from the U.S. National Science Foundation (NSF) to support their work with the Large Hadron Collider (LHC), which is scheduled to come back online in 2022 after a planned shutdown period devoted to upgrades and maintenance.

    “It is exciting, because it allows us to continue research that helps to answer these basic questions: What is the universe made of, and how do the most fundamental particles interact with each other?” says Ia Iashvili, PhD, professor of physics in the UB College of Arts and Sciences.

    Iashvili is principal investigator on the new NSF grant. Her colleagues in the physics department, Professor Avto Kharchilava, PhD, and Associate Professor Salvatore Rappoccio, PhD, are co-principal investigators.

    Probing the fundamental nature of the universe.

    The LHC is the world’s most powerful particle accelerator, consisting of “a 27-kilometer ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way,” according to the European Organization for Nuclear Research (CERN), where the collider is located.

    Thousands of scientists work together on LHC experiments, smashing beams of protons into one another at near-light speeds to produce various subatomic particles (including, perhaps most famously, the Higgs boson).

    UB physicists have been part of this international collaboration for a long time, as Kharchilava outlined in a magazine article in The Innovation Platform earlier this year. Years ago, Iashvili and Kharchilava helped to build the Compact Muon Solenoid (CMS), one of the particle detectors that researchers use to observe the results of proton-proton collisions at the LHC.

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

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

    The new NSF grant supports UB’s continuing contributions to CMS activities. This encompasses research that will occur during the LHC run beginning in 2022, as well as work that will help prepare the CMS to handle conditions at the High-Luminosity LHC, an anticipated substantial upgrade of the collider.

    Experimental goals include conducting more precise measurements of known particles and forces, and performing searches for yet undiscovered particles.

    As Iashvili explains, “These are particles predicted by theories beyond the Standard Model. The Standard Model is basically our working theory in particle physics, and it has been very successful, because it describes interactions between particles, and their properties, but we know it’s not complete. For example, it doesn’t explain matter-anti-matter asymmetry. It doesn’t tell us, ‘Why do we have dark matter or dark energy?’ There are other open questions. The Standard Model of particle physics is a beautiful theory, but it is understood to be only a low-energy approximation of a more complete theory.”

    Engaging the next generation of scientists

    Students will play an active role in the research — a chance to work at the frontier of high-energy physics.

    One team member, AC Williams, a UB PhD candidate in physics, is stationed at CERN as the LHC gears up for its next run. Williams, whose research interests include the hunt for dark matter, is the recipient of a fellowship through the NSF Alliances for Graduate Education and the Professoriate program, which seeks to improve access to STEM education for underrepresented minorities.

    UB physicists will also partner with UB’s Women in Science and Engineering initiative and engage high school teachers and students in hands-on science through the QuarkNet and Science Olympiad programs.

    “We have master classes where high school students are brought into contact with the type of research we do,” Iashvili says. “They learn about high-energy research and analyze some CMS data, and they get pretty excited about this, because the fundamental nature of this research is very appealing to them. It’s exciting to try to answer this question: What is the universe made of?”

    “Education of the younger generation is one of the most important responsibilities of scientists,” Rappoccio says. “We have a responsibility to ensure more equitable access to scientific endeavors for people from all backgrounds, especially those from underrepresented groups who have traditionally been excluded from academia.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    SUNY Buffalo Campus

    The State University of New York at Buffalo is a public research university with campuses in Buffalo and Amherst, New York, United States. The university was founded in 1846 as a private medical college and merged with the State University of New York system in 1962. It is one of four university centers in the system, in addition to The University at Albany-SUNY (US), The University at Binghampton-SUNY (US), and The University at Stony Brook-SUNY (US) . As of fall 2020, the university enrolls 32,347 students in 13 colleges, making it the largest public university in the state of New York.

    Since its founding by a group which included future United States President Millard Fillmore, the university has evolved from a small medical school to a large research university. Today, in addition to the College of Arts and Sciences, the university houses the largest state-operated medical school, dental school, education school, business school, engineering school, and pharmacy school, and is also home to SUNY’s only law school. The University at Binghampton has the largest enrollment, largest endowment, and most research funding among the universities in the SUNY system. The university offers bachelor’s degrees in over 100 areas of study, as well as 205 master’s degrees, 84 doctoral degrees, and 10 professional degrees. The University at Buffalo and The University of Virginia (US) are the only colleges founded by United States Presidents.

    The University at Buffalo is classified as an R1 University, meaning that it engages in a very high level of research activity. In 1989, UB was elected to The Association of American Universities (US), a selective group of major research universities in North America. University at Buffalo’s alumni and faculty have included five Nobel laureates, five Pulitzer Prize winners, one head of government, two astronauts, three billionaires, one Academy Award winner, one Emmy Award winner, and Fulbright Scholars.

    The University at Buffalo intercollegiate athletic teams are the Bulls. They compete in Division I of the NCAA, and are members of the Mid-American Conference.

    The University at Buffalo is organized into 13 academic schools and colleges.

    The School of Architecture and Planning is the only combined architecture and urban planning school in the State University of New York system, offers the only accredited professional master’s degree in architecture, and is one of two SUNY schools that offer an accredited professional master’s degree in urban planning. In addition, the Buffalo School of Architecture and Planning also awards the original undergraduate four year pre-professional degrees in architecture and environmental design in the SUNY system. Other degree programs offered by the Buffalo School of Architecture and Planning include a research-oriented Master of Science in architecture with specializations in historic preservation/urban design, inclusive design, and computing and media technologies; a PhD in urban and regional planning; and, an advanced graduate certificate in historic preservation.
    The College of Arts and Sciences was founded in 1915 and is the largest and most comprehensive academic unit at University at Buffalo with 29 degree-granting departments, 16 academic programs, and 23 centers and institutes across the humanities, arts, and sciences.
    The School of Dental Medicine was founded in 1892 and offers accredited programs in DDS, oral surgery, and other oral sciences.
    The Graduate School of Education was founded in 1931 and is one of the largest graduate schools at University at Buffalo. The school has four academic departments: counseling and educational psychology, educational leadership and policy, learning and instruction, and library and information science. In academic year 2008–2009, the Graduate School of Education awarded 472 master’s degrees and 52 doctoral degrees.
    The School of Engineering and Applied Sciences was founded in 1946 and offers undergraduate and graduate degrees in six departments. It is the largest public school of engineering in the state of New York. University at Buffalo is the only public school in New York State to offer a degree in Aerospace Engineering
    The School of Law was founded in 1887 and is the only law school in the SUNY system. The school awarded 265 JD degrees in the 2009–2010 academic year.
    The School of Management was founded in 1923 and offers AACSB-accredited undergraduate, MBA, and doctoral degrees.
    The School of Medicine and Biomedical Sciences is the founding faculty of the University at Buffalo and began in 1846. It offers undergraduate and graduate degrees in the biomedical and biotechnical sciences as well as an MD program and residencies.
    The School of Nursing was founded in 1936 and offers bachelors, masters, and doctoral degrees in nursing practice and patient care.
    The School of Pharmacy and Pharmaceutical Sciences was founded in 1886, making it the second-oldest faculty at University at Buffalo and one of only two pharmacy schools in the SUNY system.
    The School of Public Health and Health Professions was founded in 2003 from the merger of the Department of Social and Preventive Medicine and the University at Buffalo School of Health Related Professions. The school offers a bachelor’s degree in exercise science as well as professional, master’s and PhD degrees.
    The School of Social Work offers graduate MSW and doctoral degrees in social work.
    The Roswell Park Graduate Division is an affiliated academic unit within the Graduate School of UB, in partnership with Roswell Park Comprehensive Cancer Center, an independent NCI-designated Comprehensive Cancer Center. The Roswell Park Graduate Division offers five PhD programs and two MS programs in basic and translational biomedical research related to cancer. Roswell Park Comprehensive Cancer Center was founded in 1898 by Dr. Roswell Park and was the world’s first cancer research institute.

    The University at Buffalo houses two New York State Centers of Excellence (out of the total 11): Center of Excellence in Bioinformatics and Life Sciences (CBLS) and Center of Excellence in Materials Informatics (CMI). Emphasis has been placed on developing a community of research scientists centered around an economic initiative to promote Buffalo and create the Center of Excellence for Bioinformatics and Life Sciences as well as other advanced biomedical and engineering disciplines.

    Total research expenditures for the fiscal year of 2017 were $401 million, ranking 59th nationally.

    SUNY – The State University of New York (US) is a system of public colleges and universities in New York State. It is the largest comprehensive system of universities, colleges, and community colleges in the United States, with a total enrollment of 424,051 students, plus 2,195,082 adult education students, spanning 64 campuses across the state. The SUNY system has some 7,660 degree and certificate programs overall and a $13.08 billion budget.

    The SUNY system has four “university centers”: The University at Albany- SUNY (US) (1844), The University at Binghampton-(SUNY)(US) (1946), The University at Buffalo-SUNY (US) (1846), and The University at Stony Brook-SUNY (US) (1957). SUNY’s administrative offices are in Albany, the state’s capital, with satellite offices in Manhattan and Washington, D.C. With 25,000 acres of land, SUNY’s largest campus is The SUNY College of Environmental Science and Forestry (US), which neighbors the State University of New York Upstate Medical University – the largest employer in the SUNY system with over 10,959 employees. While the SUNY system doesn’t officially recognize a flagship university, the University at Buffalo and Stony Brook University are sometimes treated as unofficial flagships.

    The State University of New York was established in 1948 by Governor Thomas E. Dewey, through legislative implementation of recommendations made by the Temporary Commission on the Need for a State University (1946–1948). The commission was chaired by Owen D. Young, who was at the time Chairman of General Electric. The system was greatly expanded during the administration of Governor Nelson A. Rockefeller, who took a personal interest in design and construction of new SUNY facilities across the state.

    Apart from units of the unrelated City University of New York (CUNY)(US), SUNY comprises all state-supported institutions of higher education.

  • richardmitnick 11:45 am on December 11, 2021 Permalink | Reply
    Tags: "Husker team takes leading role at CERN’s Large Hadron Collider", , , CERN CH CMS, , , , , ,   

    The University of Nebraska-Lincoln (US) : “Husker team takes leading role at CERN’s Large Hadron Collider” 

    The University of Nebraska-Lincoln (US)

    Ken Bloom,
    Professor of Physics

    The University of Nebraska–Lincoln has received a five-year, $51 million grant from The National Science Foundation (US) that will advance cutting-edge work in subatomic physics at CERN’s Large Hadron Collider, the world’s largest, most powerful particle accelerator located near Geneva, Switzerland.

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

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

    The grant — one of the largest in the university’s history — will enable 1,200 U.S. physicists from 51 institutions to maximize the potential of the Compact Muon Solenoid [CMS] detector, an instrument at the collider used to study what happens when high-energy particles collide.

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

    The funding will support the U.S. CMS Operations Program, the NSF-funded portion of which Nebraska will now lead through 2026. The program, also funded by The Department of Energy (US), maintains the operation of the U.S.-supplied-and-developed components of the CMS detector, oversees its software and computing infrastructure, and plans for future upgrades.

    The operations program is foundational to maintaining and upgrading the CMS detector. The instrument functions as a giant high-speed camera within the LHC, capturing “photographs” of particle collisions that help scientists unlock mysteries about the universe’s origins and composition and glean insight into the laws of nature. The detector was integral to the 2012 discovery of the long-sought-after Higgs boson particle and is expected to spur further discoveries in particle physics.

    As a leader of the operations program, Nebraska is charged with distributing funds to 19 partnering institutions, all of which are leaders in the field of particle physics. They include The Massachusetts Institute of Technology (US), The California Institute of Technology (US), Princeton University (US) and Cornell University (US).

    Maintaining the CMS detector — which is 14,000 tons and has two endcaps each the size of a five-story building — is a significant undertaking and is the backbone to the research conducted at CERN.

    “No one can do the research unless we do the operations and maintenance,” said Ken Bloom, professor of physics and the project’s principal investigator. “It enables research on this campus and at the 50 other CMS universities in the U.S. The whole international collaboration needs these activities in the U.S. to be successful.”

    [CMS operations in the U.S.A. are based at DOE’s Fermi National Accelerator Laboratory (US) where there are 1000 people working on this project.]

    Bloom’s deep experience in CMS operations and management was pivotal in bringing the NSF funding to Nebraska. For nearly a decade, he led the team that runs the seven U.S. Tier-2 computing centers for the CMS detector, one of which is housed at the university’s Holland Computing Center. Collectively, these sites process, store, transfer and analyze the millions of gigabytes of data produced by the CMS each year.

    He was also manager of software and computing for the operations program from 2015 to 2019, managing a $16 million annual budget. In January, he was selected as the program’s deputy manager, helping to administer a $35 million budget that funds at least 45 institutions. That appointment triggered the shift in NSF funding to Nebraska from Princeton University, where it’s been housed for the past decade.

    “This grant is a capstone to Ken’s long-term dedication to leading CMS operations on the national and global scale,” said Bob Wilhelm, vice chancellor for research and economic development. “His commitment to maximizing the instrument’s potential and strengthening its computing infrastructure, and the role our university will play in managing CMS operations, paves the way for scientists at Nebraska and around the world to continue making groundbreaking discoveries in physics.”

    The university takes over at a critical point in time for the Large Hadron Collider. The instrument is poised to begin its third data-taking run in 2022, which is expected to double the size of the current CMS data set of proton collisions. In addition, a major upgrade to the accelerator is in progress, which will increase its luminosity by a factor of 10. The improved collider, to be called the High-Luminosity LHC, is expected to be in place for the fourth run’s launch in 2027 and will significantly boost the number of collisions that physicists can study.

    With the expected data boom stemming from these two events, Bloom said it’s critical to devote a lion’s share of the NSF funds to enhancing the computing operations that support data analysis. The majority of the funds that stay on Nebraska’s campus will support improved software and computing power and personnel at the Holland Center.

    The updated instruments at CERN will power additional research focused on the Higgs boson, the elementary particle that is believed to give other particles their mass.

    European Organization for Nuclear Research [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) CMS Higgs Event May 27, 2012.

    After finally discovering the so-called “God particle” in 2012 after a more than 50-year hunt, physicists are now confirming its role in the Standard Model of particle physics and using it to search for other types of hidden particles.

    Standard Model of Particle Physics, Quantum Diaries

    The upgraded LHC will double the supply of Higgs bosons available for study and provide higher-precision measurements of the particle.

    The collider also paves the way for further exploration of Dark Matter, an invisible substance believed to compose about 25% of the universe. Scientists know it exists based on gravitational pulls exhibited by distant stars and galaxies, but they don’t know what types of particles compose it.

    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky.
    Coma cluster via NASA/ESA Hubble, the original example of Dark Matter discovered during observations by Fritz Zwicky and confirmed 30 years later by Vera Rubin.
    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

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

    They’ll also continue their studies into unknown aspects of the universe: new particles, interactions and physics principles.

    In addition to Bloom, Nebraska physicists Dan Claes, Frank Golf and Ilya Kravchenko conduct research alongside national and international counterparts at CERN.

    “At Nebraska, our research in physics has been a strength for decades, and this NSF grant recognizes that, along with our demonstrated ability to provide leadership on the international stage,” said Chancellor Ronnie Green. “We embrace yet another opportunity to collaborate with colleagues around the world under the leadership of Dr. Ken Bloom to advance on these grand challenges in physics.”

    The CMS Operations Program affords hundreds of postdoctoral researchers and students the opportunity to participate in particle physics research using the world’s most advanced instruments. It also helps fund QuarkNet, a longstanding program that partners high school teachers with particle physics scientists to bring innovative research into classrooms.

    For Bloom, who’s spent much of his career conducting research in top-quark physics, weak particle interactions and the Higgs boson, this project is an opportunity to give back to a research community he’s been a part of for more than 30 years. He views it as an act of community service and a chance to pass the baton to up-and-coming physicists who will lead the next generation of discoveries.

    “I’m always looking for ways to make people’s lives better in this field,” he said. “How can we do things that will impact a lot of people and help them get their science done? This is what the operations program is, ultimately. If I can do things that will help other people pursue their science ideas, then that’s a useful contribution.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Nebraska–Lincoln (US) is a public research university in the city of Lincoln, in the state of Nebraska in the Midwestern United States. It is the state’s oldest university, and the largest in the University of Nebraska system.

    The state legislature chartered the university in 1869 as a land-grant university under the 1862 Morrill Act, two years after Nebraska’s statehood into the United States. Around the turn of the 20th century, the university began to expand significantly, hiring professors from eastern schools to teach in the newly organized professional colleges while also producing groundbreaking research in agricultural sciences. The “Nebraska method” of ecological study developed here during this time pioneered grassland ecology and laid the foundation for research in theoretical ecology for the rest of the 20th century. The university is organized into eight colleges on two campuses in Lincoln with over 100 classroom buildings and research facilities.

    Its athletic program, called the Cornhuskers, is a member of the Big Ten Conference. The Nebraska football team has won 46 conference championships, and since 1970, five national championships. The women’s volleyball team has won four national championships along with eight other appearances in the Final Four. The Husker football team plays its home games at Memorial Stadium, selling out every game since 1962. The stadium’s capacity is about 92,000 people, larger than the population of Nebraska’s third-largest city.

  • richardmitnick 4:17 pm on October 29, 2021 Permalink | Reply
    Tags: "A triple treat from CMS", , , CERN CH CMS, , , , ,   

    From CERN (CH) CMS: “A triple treat from CMS” 

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

    Cern New Bloc

    Cern New Particle Event

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

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

    29 October, 2021
    Ana Lopes

    In a first for particle physics, the CMS collaboration has observed three J/ψ particles emerging from a single collision between two protons.


    It’s a triple treat. By sifting through data from particle collisions at the Large Hadron Collider (LHC), the CMS collaboration has seen not one, not two but three J/ψ particles emerging from a single collision between two protons. In addition to being a first for particle physics, the observation opens a new window into how quarks and gluons are distributed inside the proton.

    The J/ψ particle is a special particle. It was the first particle containing a charm quark to be discovered, winning Burton Richter and Samuel Ting a Nobel prize in physics and helping to establish the quark model of composite particles called hadrons.

    Experiments including ATLAS, CMS and LHCb at the LHC have previously seen one or two J/ψ particles coming out of a single particle collision, but never before have they seen the simultaneous production of three J/ψ particles – until the new CMS analysis.

    The trick? Analysing the vast amount of high-energy proton–proton collisions collected by the CMS detector during the second run of the LHC, and looking for the transformation of the J/ψ particles into pairs of muons, the heavier cousins of the electrons.

    From this analysis, the CMS team identified five instances of single proton–proton collision events in which three J/ψ particles were produced simultaneously. The result has a statistical significance of more than five standard deviations – the threshold used to claim the observation of a particle or process in particle physics.

    These three-J/ψ events are very rare. To get an idea, one-J/ψ events and two-J/ψ events are about 3.7 million and 1800 times more common, respectively. “But they are well worth investigating,” says CMS physicist Stefanos Leontsinis, “A larger sample of three-J/ψ events, which the LHC should be able to collect in the future, should allow us to improve our understanding of the internal structure of protons at small scales.”

    See the full article here.

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  • 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", CERN CH CMS, , 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., , , , 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.

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  • richardmitnick 1:38 pm on August 7, 2021 Permalink | Reply
    Tags: "Successful installation of the CMS Pixel Tracker", , , CERN CH CMS, , , ,   

    From CERN (CH) CMS: “Successful installation of the CMS Pixel Tracker” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    From CERN (CH) CMS

    The pixel tracker is the subdetector that is closest to the beamline in the CMS experiment. Image: CERN.

    After more than two years of maintenance and upgrades, the Pixel Tracker has been installed at the centre of the CMS detector and is now ready for commissioning.

    Of all the CMS subdetectors, the Pixel Tracker is the closest to the interaction point (IP) – the point of collision between the proton beams. In the core of the detector, it reconstructs the paths of high-energy electrons, muons and electrically charged hadrons, but also the decay of very short-lived particles such as those containing beauty or “b” quarks. Those decays are used, among other things, to study the differences between matter and antimatter.

    The Pixel Tracker is composed of concentric layers and rings of 1800 small silicon modules. Each of these modules contains about 66 000 individual pixels, for a total of 120 million pixels. The pixels’ tiny size (100×150 μm2) allows the trajectory of a particle passing through the detector to be precisely measured and its origin determined with a precision of about 10 μm.

    Due to its location very close to the IP, the Pixel Tracker suffers a great deal of radiation damage from particle collisions. In the innermost layer, a mere 2.9 cm away from the beam pipe, around 600 million particles pass through one square centimetre of the detector every second. Low temperatures help to protect the Pixel Tracker from this high radiation (it is kept at -20 °C), but some damage still occurs.

    To tackle this issue, the subdetector underwent extensive repairs and upgrades in the clean room where it was stored after its extraction from the cavern at the beginning of Long Shutdown 2. Its design was improved and its innermost layer replaced. The pixel detector was then reinstalled at the centre of the CMS detector and is now ready for commissioning.

    The final installation was the latest of the many achievements of the CMS Tracker group, one of the largest sub-groups of the CMS collaboration with about 600 people from over 70 institutions in 19 countries.

    Relive the event, including footage of the operations and interviews from Lea Caminada, John Conway and Erik Butz, on CERN’s social media channels:

    CERN’s YouTube channel
    CERN’s Instagram account

    CMS Pixel tracker installation 2021

    See the full article here.

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  • richardmitnick 10:27 pm on July 26, 2021 Permalink | Reply
    Tags: "Triple Treat! CMS observes production of three massive vector bosons", , , CERN CH CMS, , , ,   

    From CERN (CH) CMS: “Triple Treat! CMS observes production of three massive vector bosons” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    From CERN (CH) CMS

    Recovered 7.26.21


    The CMS collaboration has released the first observation of the simultaneous production of three W or Z bosons in proton-proton collisions at the Large Hadron Collider (LHC). The result is based on the data collected by CMS during 2016–2018 at a collision energy of 13 TeV.

    The Standard Model of the fundamental particles describes the W and Z bosons as the mediator particles of the weak force – one of the four known fundamental forces – which is responsible for the phenomenon of radioactivity as well as an essential ingredient to our Sun’s thermonuclear process.

    It is possible for the W and Z bosons to self-interact, so W and Z bosons can create more W and Z bosons, which can manifest themselves as events with two or three massive bosons. Still, this creation is rare, so the more bosons, the less frequent they are produced. Processes with two massive bosons have been observed and measured to good precision at the LHC.

    Figure: An event collected by the CMS experiment in 2016, where two W bosons and one Z boson were produced. One W boson decayed to a muon and its neutrino, the other to an electron and its neutrino. Neutrinos cannot be detected by the CMS experiment so are inferred from the missing transverse momentum pTmiss. The Z boson decayed to two oppositely charged muons.

    The phenomenon of three massive bosons appearing in the same event is 50 times rarer than the production of the Higgs boson, which was observed at CERN in 2012. Since weak bosons are highly unstable, they almost immediately decay to electrons, muons, taus, neutrinos or quarks – the latter forming sprays of particles, called “jets”. Besides neutrinos, all of these particles can be observed with the CMS detector, a highly sophisticated “camera” capturing snapshots of the proton-proton collisions at the LHC, but not necessarily at 100% efficiency.

    The easiest way to identify the W and Z boson is when they decay to electrons or muons. With three bosons, we expect up to six electrons or muons, something that is extremely unlikely to happen at the LHC. Since in that case only some W and Z boson decay modes can be used, only a fraction of the events containing the massive bosons can eventually be studied in the detector, making the observation even more challenging. Moreover, other events produced in proton-proton collisions tend to mimic the three massive bosons signature, making it a difficult task to tell them apart. Machine learning algorithms are deployed in the analysis to improve the performance of the lepton efficiency, and to distinguish actual tri-boson events from the background.

    After the analysis a sample of tri-boson events was isolated with a significance of 5.7 standard deviations, meaning that the chance that this observation is not real is about one in eight million. This is the first observation of heavy tri-boson production at the LHC, well above the well-established 5-sigma threshold that particle physicists use to claim a discovery. The measured number of the collisions consistent with three W or Z bosons agrees with the predictions of the Standard Model, the best current understanding of fundamental particles and their interactions.

    The observation of these extremely infrequent tri-boson events is the first step towards confirming the existence of the quartic self-interaction between the massive electroweak bosons. The result also opens up a new window to look for possible deviations from the predictions of the Standard Model, which may direct us to where to search for the existence of new particles, for example, additional Higgs bosons carrying an electric charge different than that predicted by the Standard Model.

    This first look at this rare process is only the start, and in future runs of the LHC and High-luminosity LHC will provide the data to further study the interactions between the bosons, and eventually get a more in-depth probe into establishing the underlying structure of the Standard Model.

    Science paper:
    Physical Review Letters

    See the full article here.

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  • richardmitnick 2:48 pm on April 25, 2021 Permalink | Reply
    Tags: "Search for New Physics with one charged lepton and missing energy", , , CERN CH CMS, , , ,   

    From CERN (CH) CMS: “Search for New Physics with one charged lepton and missing energy” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    From CERN (CH) CMS

    CMS Collaboration

    Figure 1. Collision event recorded by the CMS experiment, with a balanced high energy electron and missing transverse momentum. The display shows the highest transverse mass (MT) event collected in LHC Run 2 in the electron channel. The event has MT = 3.1 TeV, and the electron energy deposit is shown in the long green bar at the top of the display. The purple line denotes the direction of the missing transverse momentum.

    Event display with an electron. This is the highest MT muon+MET event recorded by CMS in Run 2

    Experimental evidence from the last half-century has established the standard model as a foundational theory of particle physics.

    Still, it is clear that the standard model is not the final theory. There are many open questions: Is the mass of Higgs natural or fine-tuned? If natural, what new physics (symmetry) governs this? How does gravity play with the other forces? Are there more space dimensions than the familiar three? Do all forces unify at high energy? Many compelling theoretical ideas of new physics beyond the standard model have been proposed to address the open questions. Interestingly, many of these new theories have in common that they introduce new massive particles or differences in the behavior of known particles. If these new phenomena exist in the real world, LHC is best positioned to observe them.

    Such new particles could be a new charged W’ boson particle decaying into one charged lepton (electron or muon) and a neutrino in the proton-proton collision events recorded in the CMS detector. The W’ boson is usually predicted as a carbon copy of the W boson in the standard model, but it is very heavy, so it can also decay into the two heaviest quarks. In this analysis, the events where the W’ decays to a lepton and neutrino are taken into account because leptons are extremely clean signatures in the detector and give lower contributions from standard model processes that mimic this signature than the hadronic channels. The charged leptons can be accurately detected and measured in the CMS detector, whereas neutrinos are weakly interacting particles that will escape the detector without a signal. Nevertheless, their presence can be inferred by momentum conservation in the transverse plane. We sum the transverse momenta of all the detected particles in the event and assign the missing transverse momentum (generally called MET) to the neutrinos.

    To separate the W’ signal events from the standard model background events, CMS physicists select events with specific properties: the charged lepton and neutrino must be very energetic, the ratio of their energies has to be almost one, and they have to be back-to-back in the plane perpendicular to the beam axis. The event displays of the observed event for electron and muon channels are shown in Figure 1 and 2. One of the main tasks in this analysis is calibrating, identifying, and correctly measuring the most energetic electrons and muons ever detected in a collider experiment. For the invisible neutrino, as stated above, we can only estimate its transverse component so that the mass of the parent particle can be constrained by the transverse mass (MT). This quantity is a key one in this new physics search that distinguishes the standard model W from the new massive W’ one. Assume W’ exists and promptly decayed into two particles. In that case, the signal will be appearing as a peak (called a resonance) at the very high MT tail region, where background events hardly exist making the resonance relatively easy to spot.

    An example of the transverse mass distributions we observed is shown in Figure 3. The experimental data agree well with the standard model expectation, and there is no hint of significant deviation.

    Figure 2: Collision event recorded by the CMS experiment, with a balanced high energy muon and missing transverse momentum. The display shows the highest transverse mass (MT) event collected in LHC Run 2 in the muon channel. The event has MT = 2.9 TeV, and the muon is shown as a red line. The purple line denotes the direction of the missing transverse momentum.

    With these data, it is possible to do two different kinds of search. Figure 3 illustrates the two scenarios: on one side, we assume the new hypothetical W’ particle can be produced at the LHC, and we look for it in our data. This is called a “direct resonance search”, as the resonance from the particle should be directly visible in the data. But the new particle might be very massive and not directly reachable with the current LHC energy. In that case, we might be able to see some hints of it, as explained in Figure 4. This is the “indirect search” and it places restrictions on how far this new physics could lie.

    Figure 3. Transverse mass distribution for events with one energetic lepton (muon) and considerable missing transverse momentum. Shown are the observed data (black dots), the predicted standard model background contributions (colored blocks), and signals with two specific Sequential Standard Model W’ masses of 3.8 TeV (purple line) and 5.6 TeV (green line). The lower panels show the difference between the observed data and the background estimate.

    As the data agrees with what we expect, we can set limits on the new particle’s properties. These results can also be used to constrain a variety of other new physics models predicting a lepton and a neutrino in the final state. This approach (called reinterpretation) tests a host of different physics predictions like the existence of new spatial dimensions, new symmetries in nature, and more. We have also combined all of these interpretations of the data to look for a different effect of new physics: the hypothesis that the Higgs boson we discovered is not an elementary particle but is made of other undiscovered particles. This is known as the Composite Higgs scenario. With this analysis, we can explore this model in a complementary approach to looking at Higgs bosons.

    Figure 4. Sketch showing two kinds of possibilities studied in this analysis. The new particles are at reach at the LHC (direct search), or they are very massive and beyond LHC energy, but they still change the distributions slightly (indirect search).

    It is fascinating to explore an unprecedented region for new particles. As the center-of-mass energy and the amount of accumulated data increases, more signal-like higher MT events can be observed at LHC. This will improve sensitivity for the discovery of the W’ boson if it is slightly too heavy to be seen up to now.

    A new LHC era will soon begin with Run3 (2022-2024) which plans to double the amount of data collected during Run2 (2016-2018). Furthermore, High-Luminosity LHC is scheduled to come into operation at the end of 2027 after upgrading all of the equipment (2025-2027). High-Luminosity LHC will enable us to investigate up to 20 times more data than Run2. With these data, we can test the vast scope of many new theoretical physics models much more effectively. This will lead us towards a deeper understanding of our universe and hopefully unlock many mysteries.

    See the full article here.

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  • richardmitnick 10:09 am on March 14, 2021 Permalink | Reply
    Tags: "Searching for elusive supersymmetric particles", , , CERN CH CMS, , , , , ,   

    From UC Riverside(US): “Searching for elusive supersymmetric particles” 

    UC Riverside bloc

    From UC Riverside(US)

    March 10, 2021
    Iqbal Pittalwala
    Senior Public Information Officer
    (951) 827-6050

    CMS. Credit: CERN

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

    The Standard Model of particle physics is the best explanation to date for how the universe works at the subnuclear level and has helped explain, correctly, the elementary particles and forces between them.

    Standard Model of Particle Physics (LATHAM BOYLE AND MARDUS OF WIKIMEDIA COMMONS).

    But the model is incomplete, requiring “extensions” to address its shortfalls.

    Owen Long, a professor of physics and astronomy at the University of California, Riverside, is a key member of an international team of scientists that has explored supersymmetry, or SUSY, as an extension of the Standard Model.

    He is also a member of the Compact Muon Solenoid, or CMS, Collaboration at the Large Hadron Collider at CERN in Geneva. CMS is one of CERN’s large particle-capturing detectors.

    “The data from our CMS experiments do not allow us to claim we have found SUSY,” Long said. “But in science, not finding something — a null result — can also be exciting.”

    A theory of physics beyond the Standard Model, SUSY refers to the symmetry between two kinds of elementary particles, bosons and fermions, and is tied to their spins. SUSY proposes that all known fundamental particles have heavier, supersymmetric counterparts, with each supersymmetric partner differing from its Standard Model counterpart by one-half unit in spin. This doubles the number of particle types in nature, allowing many new interactions between the regular particles and new SUSY particles.

    “This is a big change to the Standard Model,” Long said. “The extension can provide answers to some of the fundamental questions that are still unanswered, such as: What is dark matter?”

    The Standard Model explains neither gravity nor dark matter. But in the case of the latter, SUSY does offer a candidate in the form of the lightest supersymmetric particle, which is stable, electrically neutral, and weakly interacting. The invocation of SUSY also naturally explains the small mass of the Higgs boson.

    “The discovery of the elusive SUSY particles would provide an extraordinary insight into the nature of reality,” Long said. “And it would be a revolutionary moment in physics for experimentalists and theorists.”

    At CMS, Long and other scientists hoped to find evidence for SUSY particles by examining signs of their decay as measured by an energy imbalance called missing transverse energy. When they examined the data, they found no signs of the expected energy imbalance from producing SUSY particles.

    “We, therefore, have no evidence for SUSY,” Long said. “But perhaps SUSY is there, and it is just more hidden than initially thought. It’s true we did not find something new, which is disappointing. But it is still very important scientific progress. We now know a lot more about where SUSY does not exist. Our null result motivates us to do follow-up work and guides us where to look next.”

    Long explained that he and his fellow scientists have been looking for SUSY for a long time through a technique based on a connection to dark matter.

    “Those efforts did not find SUSY particles,” he said. “Our new result involves a completely different approach, developed over a couple of years and driven by our interest in looking for SUSY in novel ways. While we found no evidence for SUSY, there is still interest in exploring the idea that SUSY could exist in ways that are more difficult to find. We already have preliminary measurements we are working on.”

    Long was funded by a grant from the Department of Energy. He was joined by three other senior scientists from other institutions in the research.

    UCR is a founding member of the CMS experiment — one of only five U.S. institutions with that distinction.

    Science paper:
    Search for top squarks in final states with two top quarks and several light-flavor jets in proton-proton collisions at s√= 13 TeV.
    Physical Review D

    See the full article here .


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    UC Riverside Campus

    The University of California, Riverside(US) is a public land-grant research university in Riverside, California. It is one of the 10 campuses of the University of California(US) system. The main campus sits on 1,900 acres (769 ha) in a suburban district of Riverside with a branch campus of 20 acres (8 ha) in Palm Desert. In 1907, the predecessor to UC Riverside was founded as the UC Citrus Experiment Station, Riverside which pioneered research in biological pest control and the use of growth regulators responsible for extending the citrus growing season in California from four to nine months. Some of the world’s most important research collections on citrus diversity and entomology, as well as science fiction and photography, are located at Riverside.

    UC Riverside’s undergraduate College of Letters and Science opened in 1954. The Regents of the University of California declared UC Riverside a general campus of the system in 1959, and graduate students were admitted in 1961. To accommodate an enrollment of 21,000 students by 2015, more than $730 million has been invested in new construction projects since 1999. Preliminary accreditation of the UC Riverside School of Medicine was granted in October 2012 and the first class of 50 students was enrolled in August 2013. It is the first new research-based public medical school in 40 years.

    UC Riverside is classified among “R1: Doctoral Universities – Very high research activity.” The 2019 U.S. News & World Report Best Colleges rankings places UC Riverside tied for 35th among top public universities and ranks 85th nationwide. Over 27 of UC Riverside’s academic programs, including the Graduate School of Education and the Bourns College of Engineering, are highly ranked nationally based on peer assessment, student selectivity, financial resources, and other factors. Washington Monthly ranked UC Riverside 2nd in the United States in terms of social mobility, research and community service, while U.S. News ranks UC Riverside as the fifth most ethnically diverse and, by the number of undergraduates receiving Pell Grants (42 percent), the 15th most economically diverse student body in the nation. Over 70% of all UC Riverside students graduate within six years without regard to economic disparity. UC Riverside’s extensive outreach and retention programs have contributed to its reputation as a “university of choice” for minority students. In 2005, UCR became the first public university campus in the nation to offer a gender-neutral housing option.UC Riverside’s sports teams are known as the Highlanders and play in the Big West Conference of the National Collegiate Athletic Association (NCAA) Division I. Their nickname was inspired by the high altitude of the campus, which lies on the foothills of Box Springs Mountain. The UC Riverside women’s basketball team won back-to-back Big West championships in 2006 and 2007. In 2007, the men’s baseball team won its first conference championship and advanced to the regionals for the second time since the university moved to Division I in 2001.


    At the turn of the 20th century, Southern California was a major producer of citrus, the region’s primary agricultural export. The industry developed from the country’s first navel orange trees, planted in Riverside in 1873. Lobbied by the citrus industry, the UC Regents established the UC Citrus Experiment Station (CES) on February 14, 1907, on 23 acres (9 ha) of land on the east slope of Mount Rubidoux in Riverside. The station conducted experiments in fertilization, irrigation and crop improvement. In 1917, the station was moved to a larger site, 475 acres (192 ha) near Box Springs Mountain.

    The 1944 passage of the GI Bill during World War II set in motion a rise in college enrollments that necessitated an expansion of the state university system in California. A local group of citrus growers and civic leaders, including many UC Berkeley(US) alumni, lobbied aggressively for a UC-administered liberal arts college next to the CES. State Senator Nelson S. Dilworth authored Senate Bill 512 (1949) which former Assemblyman Philip L. Boyd and Assemblyman John Babbage (both of Riverside) were instrumental in shepherding through the State Legislature. Governor Earl Warren signed the bill in 1949, allocating $2 million for initial campus construction.

    Gordon S. Watkins, dean of the College of Letters and Science at University of California at Los Angeles(US), became the first provost of the new college at Riverside. Initially conceived of as a small college devoted to the liberal arts, he ordered the campus built for a maximum of 1,500 students and recruited many young junior faculty to fill teaching positions. He presided at its opening with 65 faculty and 127 students on February 14, 1954, remarking, “Never have so few been taught by so many.”

    UC Riverside’s enrollment exceeded 1,000 students by the time Clark Kerr became president of the University of California(US) system in 1958. Anticipating a “tidal wave” in enrollment growth required by the baby boom generation, Kerr developed the California Master Plan for Higher Education and the Regents designated Riverside a general university campus in 1959. UC Riverside’s first chancellor, Herman Theodore Spieth, oversaw the beginnings of the school’s transition to a full university and its expansion to a capacity of 5,000 students. UC Riverside’s second chancellor, Ivan Hinderaker led the campus through the era of the free speech movement and kept student protests peaceful in Riverside. According to a 1998 interview with Hinderaker, the city of Riverside received negative press coverage for smog after the mayor asked Governor Ronald Reagan to declare the South Coast Air Basin a disaster area in 1971; subsequent student enrollment declined by up to 25% through 1979. Hinderaker’s development of innovative programs in business administration and biomedical sciences created incentive for enough students to enroll at Riverside to keep the campus open.

    In the 1990s, the UC Riverside experienced a new surge of enrollment applications, now known as “Tidal Wave II”. The Regents targeted UC Riverside for an annual growth rate of 6.3%, the fastest in the UC system, and anticipated 19,900 students at UC Riverside by 2010. By 1995, African American, American Indian, and Latino student enrollments accounted for 30% of the UC Riverside student body, the highest proportion of any UC campus at the time. The 1997 implementation of Proposition 209—which banned the use of affirmative action by state agencies—reduced the ethnic diversity at the more selective UC campuses but further increased it at UC Riverside.

    With UC Riverside scheduled for dramatic population growth, efforts have been made to increase its popular and academic recognition. The students voted for a fee increase to move UC Riverside athletics into NCAA Division I standing in 1998. In the 1990s, proposals were made to establish a law school, a medical school, and a school of public policy at UC Riverside, with the UC Riverside School of Medicine and the School of Public Policy becoming reality in 2012. In June 2006, UC Riverside received its largest gift, 15.5 million from two local couples, in trust towards building its medical school. The Regents formally approved UC Riverside’s medical school proposal in 2006. Upon its completion in 2013, it was the first new medical school built in California in 40 years.


    As a campus of the University of California(US) system, UC Riverside is governed by a Board of Regents and administered by a president. The current president is Michael V. Drake, and the current chancellor of the university is Kim A. Wilcox. UC Riverside’s academic policies are set by its Academic Senate, a legislative body composed of all UC Riverside faculty members.

    UC Riverside is organized into three academic colleges, two professional schools, and two graduate schools. UC Riverside’s liberal arts college, the College of Humanities, Arts and Social Sciences, was founded in 1954, and began accepting graduate students in 1960. The College of Natural and Agricultural Sciences, founded in 1960, incorporated the CES as part of the first research-oriented institution at UC Riverside; it eventually also incorporated the natural science departments formerly associated with the liberal arts college to form its present structure in 1974. UC Riverside’s newest academic unit, the Bourns College of Engineering, was founded in 1989. Comprising the professional schools are the Graduate School of Education, founded in 1968, and the UCR School of Business, founded in 1970. These units collectively provide 81 majors and 52 minors, 48 master’s degree programs, and 42 Doctor of Philosophy (PhD) programs. UC Riverside is the only UC campus to offer undergraduate degrees in creative writing and public policy and one of three UCs (along with Berkeley and Irvine) to offer an undergraduate degree in business administration. Through its Division of Biomedical Sciences, founded in 1974, UC Riverside offers the Thomas Haider medical degree program in collaboration with UCLA.[29] UC Riverside’s doctoral program in the emerging field of dance theory, founded in 1992, was the first program of its kind in the United States, and UC Riverside’s minor in lesbian, gay and bisexual studies, established in 1996, was the first undergraduate program of its kind in the UC system. A new BA program in bagpipes was inaugurated in 2007.

    Research and economic impact

    UC Riverside operated under a $727 million budget in fiscal year 2014–15. The state government provided $214 million, student fees accounted for $224 million and $100 million came from contracts and grants. Private support and other sources accounted for the remaining $189 million. Overall, monies spent at UC Riverside have an economic impact of nearly $1 billion in California. UC Riverside research expenditure in FY 2018 totaled $167.8 million. Total research expenditures at UC Riverside are significantly concentrated in agricultural science, accounting for 53% of total research expenditures spent by the university in 2002. Top research centers by expenditure, as measured in 2002, include the Agricultural Experiment Station; the Center for Environmental Research and Technology; the Center for Bibliographical Studies; the Air Pollution Research Center; and the Institute of Geophysics and Planetary Physics.

    Throughout UC Riverside’s history, researchers have developed more than 40 new citrus varieties and invented new techniques to help the $960 million-a-year California citrus industry fight pests and diseases. In 1927, entomologists at the CES introduced two wasps from Australia as natural enemies of a major citrus pest, the citrophilus mealybug, saving growers in Orange County $1 million in annual losses. This event was pivotal in establishing biological control as a practical means of reducing pest populations. In 1963, plant physiologist Charles Coggins proved that application of gibberellic acid allows fruit to remain on citrus trees for extended periods. The ultimate result of his work, which continued through the 1980s, was the extension of the citrus-growing season in California from four to nine months. In 1980, UC Riverside released the Oroblanco grapefruit, its first patented citrus variety. Since then, the citrus breeding program has released other varieties such as the Melogold grapefruit, the Gold Nugget mandarin (or tangerine), and others that have yet to be given trademark names.

    To assist entrepreneurs in developing new products, UC Riverside is a primary partner in the Riverside Regional Technology Park, which includes the City of Riverside and the County of Riverside. It also administers six reserves of the University of California Natural Reserve System. UC Riverside recently announced a partnership with China Agricultural University[中国农业大学](CN) to launch a new center in Beijing, which will study ways to respond to the country’s growing environmental issues. UC Riverside can also boast the birthplace of two name reactions in organic chemistry, the Castro-Stephens coupling and the Midland Alpine Borane Reduction.

  • richardmitnick 2:11 pm on January 12, 2021 Permalink | Reply
    Tags: "CMS collaboration releases its first open data from heavy-ion collisions", , , CERN CH CMS, , , ,   

    From CERN (CH) CMS: “CMS collaboration releases its first open data from heavy-ion collisions” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    From CERN (CH) CMS

    12 January, 2021
    Achintya Rao

    CMS data recorded in 2010 and 2011 from lead–lead collisions at the Large Hadron Collider have been released into the public domain for the first time.

    A heavy-ion collision recorded by CMS in 2011. Credi:Tom McCauley/CMS/CERN.

    For a few weeks each year of operation, instead of colliding protons, the Large Hadron Collider (LHC) collides nuclei of heavy elements (“heavy ions”). These heavy-ion collisions allow researchers to recreate in the laboratory conditions that existed in the very early universe, such as the soup-like state of free quarks and gluons known as the quark–gluon plasma. Now, for the first time, the Compact Muon Solenoid (CMS) collaboration at CERN is making its heavy-ion data publicly available via the CERN Open Data portal.

    Over 200 terabytes (TB) of data were released in December, from collisions that occurred in 2010 and 2011, when the LHC collided bunches of lead nuclei. Using these data, CMS had observed several signatures of the quark–gluon plasma, including the imbalance between the momenta of each jet of particles produced in a pair, the suppression (“quenching”) of particle jets in jet–photon pairs and the “melting” of certain composite particles. In addition to lead–lead collision data (two data sets from 2010 and four from 2011), CMS has also provided eight sets of reference data from proton–proton collisions recorded at the same energy.

    The open data are available in the same high-quality format that was used by the CMS scientists to publish their research papers. The data are accompanied by the software that is needed to analyse them and by analysis examples. Previous releases of CMS open data have been used not only in education but also to perform novel research. CMS is hopeful that communities of professional researchers and amateur enthusiasts as well as educators and students at all levels will put the heavy-ion data to similar use.

    “Our aim with releasing CMS data into the public domain via the Creative Commons CC0 waiver is to preserve our data and the knowledge needed to use them, in order to facilitate the widest possible use of our data,” says Kati Lassila-Perini, who has led the CMS open-data project since its inception in 2012. “We hope that those outside CMS will find these data as fascinating and valuable as we do.”

    CMS has committed to releasing 100% of the data recorded each year after an embargo period of ten years, with up to 50% of the data being made available in the interim. The embargo allows the researchers who built and operate the CMS detector adequate time to analyse the data they collect. With this release, all of the research data recorded by CMS during LHC operation in 2010 and 2011 is now in the public domain, available for anyone to study.

    You can read more about the release on the CERN Open Data portal: opendata.cern.ch/docs/cms-releases-heavy-ion-data.

    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)

    CERN (CH)/CMS detector

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