Tagged: Accelerator Science Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 10:05 am on January 24, 2020 Permalink | Reply
    Tags: Accelerator Science, , , , , , , The team has been able to ramp up the machine to 500 milliamperes (mA) of current and to keep this current stable for more than six hours.,   

    From Brookhaven National Lab: “NSLS-II Achieves Design Beam Current of 500 Milliamperes” 

    From Brookhaven National Lab

    January 22, 2020
    Cara Laasch
    laasch@bnl.gov

    Accelerator division enables new record current during studies.

    1
    The NSLS-II accelerator division proudly gathered to celebrate their recent achievement. The screen above them shows the slow increase of the electron current in the NSLS-II storage ring and its stability.

    The National Synchrotron Light Source II (NSLS-II) [below] at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory is a gigantic x-ray microscope that allows scientists to study the inner structure of all kinds of material and devices in real time under realistic operating conditions. The scientists using the machine are seeking answers to questions including how can we built longer lasting batteries; when life started on our planet; and what kinds of new materials can be used in quantum computers, along with many other questions in a wide variety of research fields.

    The heart of the facility is a particle accelerator that circulates electrons at nearly the speed of light around the roughly half-a-mile-long ring. Steered by special magnets within the ring, the electrons generate ultrabright x-rays that enable scientists to address the broad spectrum of research at NSLS-II.

    Now, the accelerator division at NSLS-II has reached a new milestone for machine performance. During recent accelerator studies, the team has been able to ramp up the machine to 500 milliamperes (mA) of current and to keep this current stable for more than six hours. Similar to a current in a river, the current in an accelerator is a measure of the number of electrons that circulate the ring at any given time. In NSLS-II’s case, a higher electron current opens the pathway to more intense x-rays for all the experiments happening at the facility.

    “Since we turned on the machine for the first time in 2014 with 50mA current, we have progressed steadily upwards in current and now – in just five years – we have reached 500mA,” said Timur Shaftan, NSLS-II accelerator division director. “Along the way, we encountered many significant challenges, and it is thanks to the dedication, knowledge, and expertise of the team that we were able to overcome them all to get here.”

    All good things come in threes?

    On their quest to a higher current, the accelerator division faced three major challenges: an increase in power consumption of the radiofrequency (RF) accelerating cavities, more intense “wakefields,” and the unexpected heating of some accelerator components.

    The purpose of the RF accelerating cavities can be compared to pushing a child on a swing – with the child being the electrons. With the correct timing, large amplitudes can be driven with little effort. The cavities feed more and more energy to the electrons to compensate for the energy the electrons lose as they generate x-rays in their trips around the ring.

    “The cavities use electricity to push the electrons forward, and even though our cavities are very efficient, they still draw a good amount of raw power,” said Jim Rose, RF group leader. “To reach 500 mA, we monitored this increase closely to ensure that we wouldn’t cross our limit for power, which we didn’t. However, there is another challenge we now have to face: The cavities compress the groups of electrons—we call them bunches—that rush through the machine, and by doing so they increase the heating issues that we face. To fully address this in the future, we will install other cavities of a different RF frequency that would lengthen the bunches again.”

    Rose is referring to the issue of “wakefields.” As the electrons speed around the ring, they create so called wakefields—just like when you run your finger through still water and create waves that roll on even though your fingers are long gone. In the same way, the rushing electrons generate a front of electric fields that follow them around the ring.

    “Having more intense wakefields causes two challenges: First, these fields influence the next set of electrons, causing them to lose energy and become unstable, and second, they heat up the vacuum chamber in which the beam travels,” said accelerator physicist Alexei Blednykh. “One of the limiting components in our efforts to reach 500mA was the ceramic vacuum chambers, because they were overheating. We mitigated the effect by installing additional cooling fans. However, to fully solve the issue we will need to replace the existing chambers with new chambers that have a thin titanium coating on the inside.”

    The accelerator division decided to coat all the new vacuum chambers in house using a technique called direct current magnetron sputtering. During the sputtering process, a titanium target is bombarded with ionized gas so that it ejects millions of titanium atoms, which spray onto the surface of the vacuum chamber to create a thin metal film.

    “At first, coating chambers sounds easy enough, but our chambers are long and narrow, which forces you to think differently how you can apply the coating. We had to design a coating system that was capable of handling the geometry of our chambers,” said vacuum group leader Charlie Hetzel. “Once we developed a system that could be used to coat the chambers, we had to develop a method that could accurately measure the thickness and uniformity along the entire length of the chamber.”

    For the vacuum chambers to survive the machine at high current, the coatings had to meet a number of demanding requirements in terms of their adhesion, thickness, and uniformity.

    The third challenge the team needed to overcome was resolving the unexpected heating found between some of the vacuum flanges. Each of the vacuum joints around the half-mile long accelerator contain a delicate RF bridge. Any errors during installation can result in additional heating and risk to the vacuum seal of the machine.

    “We knew from the beginning that increasing the current to 500 mA would be hard on the machine, however, we needed to know exactly where the real hot spots were,” explained accelerator coordination group leader Guimei Wang. “So, we installed more than 1000 temperature sensors around the whole machine, and we ran more than 400 hours of high-current beam studies over the past three years, where we monitored the temperature, vacuum, and many other parameters of the electrons very closely to really understand how our machine is behaving.”

    Based on all these studies and many more hours spend analyzing each single study run, the accelerator team made the necessary decisions as to which what parts needed to be coated or changed and, most importantly, how to run the machine at such a high current safely and reliably.

    Where do we go from here?

    Achieving 500mA during beam studies was an important step to begin to shed light on the physics within the machine at these high currents, as well as to understand the present limits of the accelerator. Equipped with these new insights, the accelerator division now knows that their machine can reach the 500mA current for a short time, but at this point it’s not possible to sustain high current for operations over extended periods with the RF power necessary to deliver it to users. To run the machine at this current, NSLS-II’s accelerator will need additional RF systems both to lengthen the bunches and to secure high reliability of operations, while providing sufficient RF power to the beam to generate x-rays for the growing set of beamlines.

    “Achieving 500 mA for the first time is a major milestone in the life of NSLS-II, showing that we can reach the aggressive design current goals we set for ourselves when we first started thinking about what NSLS-II could be all those years ago. This success is due to a lot of hard work, expertise, and dedication by many, many people at NSLS-II and I would like to thank them all very much,” said NSLS-II Director John Hill. “The next steps are to fully understand how the machine behaves at this current and ultimately deliver it to our users. This will require further upgrades to our accelerator systems—and we are actively working towards those now.”

    NSLS-II is a DOE Office of Science user facility.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    Brookhaven campus

    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL Phenix Detector

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

     
  • richardmitnick 8:22 am on January 23, 2020 Permalink | Reply
    Tags: Accelerator Science, , , , , , , , ,   

    From Fermi National Accelerator Lab: “USCMS collaboration gets green light on upgrades to CMS particle detector” 

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    From Fermi National Accelerator Lab , an enduring source of strength for the US contribution to scientific research world wide.

    January 22, 2020
    Leah Hesla

    In its ongoing quest to understand the nature of the universe’s fundamental constituents, the CMS collaboration has reached another milestone.

    CERN/CMS Detector

    In October 2019, the U.S. contingent of the CMS collaboration presented their plans to upgrade the CMS particle detector for the high-luminosity phase of the Large Hadron Collider at CERN.

    CERN LHC Tunnel

    The upgrades would enable CMS to handle the challenging environment brought on by the upcoming increase in the LHC’s particle collision rate, fully exploiting the discovery potential of the upgraded machine.

    In response, on Dec. 19, 2019, the Department of Energy Office of Science gave the plan its stamp of CD-1 approval, signaling that it favorably evaluated the project’s conceptual design, schedule range and cost, among other factors.

    “This is a major achievement because it paves the way for the next major steps in our project, in which funds are allocated to start the production phase,” said scientist Anadi Canepa, head of the Fermilab CMS Department. “The U.S. project team was extremely satisfied. Preparing for CD-1 was a monumental effort.”

    2
    The CMS detector upgrade team met in October 2019 for a DOE review. Photo: Reidar Hahn, Fermilab

    The LHC’s increase in beam intensity is planned for 2027, when it will become the High-Luminosity LHC. Racing around its 17-mile circumference, the upgraded collider’s proton beams will smash together to reveal even more about the nature of the subatomic realm thanks to a 10-fold increase in collision rate compared to the LHC’s design value.

    The cranked up intensity means that the High-Luminosity LHC will deliver an unprecedented amount of data, and the giant detectors that sit in the path of the beam have to be able to withstand the higher data delivery rate and radiation dose. In preparation, USCMS will upgrade the CMS detector to keep up with the increase in data output, not to mention to harsher collision environment.

    The collaboration plans to upgrade the detector with state-of-the-art technology. The new detector will exhibit improved sensitivity, with over 2 billion sensor channels — up from 80 million. USCMS is also replacing the central part of the detector so that, when charged particles fly through it, the upgraded device will take readings of their momenta at an astounding 40 million times per second, a first for hadron colliders. They’re implementing an innovative design for the detector, measuring the energy of particles using very precise silicon sensors. The upgraded CMS will also have a breakthrough component to take higher-resolution, more precisely timed images of complex particle interactions. Scientists are introducing a system using machine learning on electronic circuits called FPGAs to more efficiently select which of the billions of particle events that CMS processes every 25 nanoseconds might signal new physics.

    “The successful completion of the CD-1 review is a reflection of the competence, commitment and dedication of a very large team of Fermilab scientists and university colleagues,” said Fermilab scientist Steve Nahn, U.S. project manager for the CMS detector upgrade.

    Now USCMS will refine the plan, getting it ready to serve as the project baseline.

    “With these improvements, we’ll be able to explore uncharted territories and might discover new phenomena that revolutionize our description of nature,” Canepa said.

    The USCMS collaboration comprises Fermilab and 54 institutions.

    See the full here.


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    FNAL Icon

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 1:19 pm on January 21, 2020 Permalink | Reply
    Tags: Accelerator Science, , , , , , ,   

    From Symmetry: “The other dark matter candidate” 

    Symmetry Mag
    From Symmetry<

    01/21/20
    Laura Dattaro

    Inside the ADMX experiment hall at the University of Washington Credit Mark Stone U. of Washington. Axion Dark Matter Experiment

    CERN CAST Axion Solar Telescope

    As technology improves, scientists discover new ways to search for theorized dark matter particles called axions.

    In the early 1970s, physics had a symmetry problem. According to the Standard Model, the guiding framework of particle physics, a symmetry between particles and forces in our universe and a mirror version should be broken.

    Standard Model of Particle Physics

    It was broken by the weak force, a fundamental force involved in processes like radioactive decay.

    This breaking should feed into the interactions mediated by another fundamental force, the strong force. But experiments show that, unlike the weak force, the strong force obeys mirror symmetry perfectly. No one could explain it.

    The problem confounded physicists for years. Then, in 1977, physicists Roberto Peccei and Helen Quinn found a solution: a mechanism that, if it existed, would cause the strong force to obey this symmetry and right the Standard Model.

    Shortly after, Frank Wilczek and Steven Weinberg—both of whom went on to win the Nobel Prize—realized that this mechanism creates an entirely new particle. Wilczek ultimately dubbed this new particle the axion, after a dish detergent with the same name, for its ability to “clean up” the symmetry problem.

    Several years later, the theoretical axion was found not only to solve the symmetry problem, but also to be a possible candidate for dark matter, the missing matter that scientists think makes up 85% of the universe but the true nature of which is unknown.

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM denied the Nobel, did most of the work on Dark Matter.

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

    Coma cluster via NASA/ESA Hubble

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


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


    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    The LSST, or Large Synoptic Survey Telescope is to be named the Vera C. Rubin Observatory by an act of the U.S. Congress.

    LSST telescope, The Vera Rubin Survey Telescope currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    LSST Data Journey, Illustration by Sandbox Studio, Chicago with Ana Kova

    Dark Matter Research

    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    Scientists studying the cosmic microwave background [CMB]hope to learn about more than just how the universe grew—it could also offer insight into dark matter, dark energy and the mass of the neutrino.

    [caption id="attachment_73741" align="alignnone" width="632"] CMB per ESA/Planck

    Dark matter cosmic web and the large-scale structure it forms The Millenium Simulation, V. Springel et al

    Dark Matter Particle Explorer China

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB deep in Sudbury’s Creighton Mine

    LBNL LZ Dark Matter project at SURF, Lead, SD, USA


    Inside the ADMX experiment hall at the University of Washington Credit Mark Stone U. of Washington. Axion Dark Matter Experiment

    Despite its theoretical promise, though, the axion stayed in relative obscurity, due to a combination of its strange nature and being outshone by another new dark matter candidate, called a WIMP, that seemed even more like a sure thing.

    But today, four decades after they were first theorized, axions are once again enjoying a moment in the sun, and may even be on the verge of detection, poised to solve two major problems in physics at once.

    “I think WIMPs have one last hurrah as these multiton experiments come online,” says MIT physicist Lindley Winslow. “Since they’re not done building those yet, we have to take a deep breath and see if we find something.

    “But if you ask me the thing we need to be ramping up, it’s axions. Because the axion has to be there, or we have other problems.”

    Around the time the axion was proposed, physicists were developing a theory called Supersymmetry, which called for a partner for every known particle.

    Standard Model of Supersymmetry via DESY

    The newly proposed dark matter candidate called a WIMP—or weakly interacting massive particle—fit beautifully with the theory of Supersymmetry, making physicists all but certain they’d both be discovered.

    Even more promising was that both the supersymmetric particles and the theorized WIMPs could be detected at the Large Hadron Collider at CERN.

    LHC

    CERN map


    CERN LHC Maximilien Brice and Julien Marius Ordan


    CERN LHC particles

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS

    CERN ATLAS Image Claudia Marcelloni CERN/ATLAS

    ALICE

    CERN/ALICE Detector


    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    “People just knew nature was going to deliver supersymmetric particles at the LHC,” says University of Washington physicist Leslie Rosenberg. “The LHC was a machine built to get a Nobel Prize for detecting Supersymmetry.”

    Experiments at the LHC made another Nobel-worthy discovery: the Higgs boson. But evidence of both WIMPS and Supersymmetry has yet to appear.

    Peter Higgs

    CERN CMS Higgs Event May 27, 2012

    CERN ATLAS Higgs Event

    Axions are even trickier than WIMPs. They’re theorized to be extremely light—a millionth of an electronvolt or so, about a trillion times lighter than the already tiny electron—making them next to impossible to produce or study in a traditional particle physics experiment. They even earned the nickname “invisible axion” for the unlikeliness they’d ever be seen.

    But axions don’t need to be made in a detector to be discovered. If axions are dark matter, they were created at the beginning of the universe and exist, free-floating, throughout space. Theorists believe they also should be created inside of stars, and because they’re so light and weakly interacting, they’d be able to escape into space, much like other lightweight particles called neutrinos. That means they exist all around us, as many as 10 trillion per cubic centimeter, waiting to be detected.

    In 1983, newly minted physics professor Pierre Sikivie decided to tackle this problem, taking inspiration from a course he had just taught on electromagnetism. Sikivie discovered that axions have another unusual property: In the presence of an electromagnetic field, they should sometimes spontaneously convert to easily detectable photons.

    “What I found is that it was impossible or extremely difficult to produce and detect axions,” Sikivie says. “But if you ask a less ambitious goal of detecting the axions that are already there, axions already there either as dark matter or as axions emitted by the sun, that actually became feasible.”

    When Rosenberg, then a postdoc working on cosmic rays at the University of Chicago, heard about Sikivie’s breakthrough—what he calls “Pierre’s Great Idea”—he knew he wanted to dedicate his work to the search.

    “Pierre’s paper hit me like a rock in the head,” Rosenberg says. “Suddenly, this thing that was the invisible axion, which I thought was so compelling, is detectable.”

    Rosenberg began work on what’s now called the Axion Dark Matter Experiment, or ADMX. The concept behind the experiment is relatively simple: Use a large magnet to create an electromagnetic field, and wait for the axions to convert to photons, which can then be detected with quantum sensors.

    When work on ADMX began, the technology wasn’t sensitive enough to pick up the extremely light axions. While Rosenberg kept the project moving forward, much of the field has focused on WIMPs, building ever-larger dark matter detectors to find them.

    But neither WIMPs nor supersymmetric particles have been discovered, pushing scientists to think creatively about what happens next.

    “That’s caused a lot of people to re-evaluate what other dark matter models we have,” says University of Michigan theorist Ben Safdi. “And when people have done that re-evaluation, the axion is the natural candidate that’s still floating around. The downfall of the WIMP has been matched exactly by the rise of axions in terms of popularity.”

    See the full article here .


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

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 9:54 am on January 20, 2020 Permalink | Reply
    Tags: "LHCb explores the beauty of lepton universality", Accelerator Science, , , , ,   

    From CERN LHCb: “LHCb explores the beauty of lepton universality” 

    Cern New Bloc

    Cern New Particle Event


    From CERN LHCb

    15 January, 2020
    Ana Lopes

    For the first time, LHCb [below] uses beauty baryons to test this key principle of the Standard Model.

    1
    A typical LHCb event from Run 2 data. Credit: OPEN-PHO-EXP-2016-007-1

    Standard Model of Particle Physics

    The LHCb collaboration has reported an intriguing new result in its quest to test a key principle of the Standard Model called lepton universality. Although not statistically significant, the finding – a possible difference in the behaviour of different types of lepton particles – chimes with other previous results. If confirmed, as more data are collected and analysed, the results would signal a crack in the Standard Model.

    Lepton universality is the idea that all three types of charged lepton particles – electrons, muons and taus – interact in the same way with other particles. As a result, the different lepton types should be created equally often in particle transformations, or “decays”, once differences in their mass are accounted for. However, some measurements of particle decays made by the LHCb team and other groups over the past few years have indicated a possible difference in their behaviour. Taken separately, these measurements are not statistically significant enough to claim a breaking of lepton universality and hence a crack in the Standard Model, but it is intriguing that hints of a difference have been popping up in different particle decays and experiments.

    The latest LHCb result is the first test of lepton universality made using the decays of beauty baryons – three-quark particles containing at least one beauty quark. Sifting through proton–proton collision data at energies of 7, 8 and 13 TeV, the LHCb researchers identified beauty baryons called Λb0 and counted how often they decayed to a proton, a charged kaon and either a muon and antimuon or an electron and antielectron.

    The team then took the ratio between these two decay rates. If lepton universality holds, this ratio should be close to 1. A deviation from this prediction could therefore signal a violation of lepton universality. Such a violation could be caused by the presence in the decays of a never-before-spotted particle not predicted by the Standard Model.

    The team obtained a ratio slightly below 1 with a statistical significance of about 1 standard deviation, well below the 5 standard deviations needed to claim a real difference in the decay rates. The researchers say that the result points in the same direction as other results, which have observed hints that decays to a muon–antimuon pair occur less often than those to an electron–antielectron pair, but they also stress that much more data is needed to tell whether this oddity in the behaviour of leptons is here to stay or not.

    See the full article here.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LHCb
    CERN LHCb New II

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier

     
  • richardmitnick 3:29 pm on January 14, 2020 Permalink | Reply
    Tags: Accelerator Science, , , , , Dilepton channel, Drell–Yan process, , , Searching for new physics in the TeV regime by looking for the decays of new particles., The dark photon (Zd)?   

    From CERN Courier: “CMS goes scouting for dark photons” 


    From CERN Courier

    6 December 2019
    A report from the CMS experiment

    One of the best strategies for searching for new physics in the TeV regime is to look for the decays of new particles. The CMS collaboration has searched in the dilepton channel for particles with masses above a few hundred GeV since the start of LHC data taking. Thanks to newly developed triggers, the searches are now being extended to the more difficult lower range of masses. A promising possible addition to the Standard Model (SM) that could exist in this mass range is the dark photon (Zd). Its coupling with SM particles and production rate depend on the value of a kinetic mixing coefficient ε, and the resulting strength of the interaction of the Zd with ordinary matter may be several orders of magnitude weaker than the electroweak interaction.

    The CMS collaboration has recently presented results of a search for a narrow resonance decaying to a pair of muons in the mass range from 11.5 to 200 GeV. This search looks for a strikingly sharp peak on top of a smooth dimuon mass spectrum that arises mainly from the Drell–Yan process. At masses below approximately 40 GeV, conventional triggers are the main limitation for this analysis as the thresholds on the muon transverse momenta (pT), which are applied online to reduce the rate of events saved for offline analysis, introduce a significant kinematic acceptance loss, as evident from the red curve in figure 1.

    1
    Fig. 1. Dimuon invariant-mass distributions obtained from data collected by the standard dimuon triggers (red) and the dimuon scouting triggers (green).

    A dedicated set of high-rate dimuon “scouting” triggers, with some additional kinematic constraints on the dimuon system and significantly lower muon pT thresholds, was deployed during Run 2 to overcome this limitation. Only a minimal amount of high-level information from the online reconstruction is stored for the selected events. The reduced event size allows significantly higher trigger rates, up to two orders of magnitude higher than the standard muon triggers. The green curve in figure 1 shows the dimuon invariant mass distribution obtained from data collected with the scouting triggers. The increase in kinematic acceptance for low masses can be well appreciated.

    The full data sets collected with the muon scouting and standard dimuon triggers during Run 2 are used to probe masses below 45 GeV, and between 45 and 200 GeV, respectively, excluding the mass range from 75 to 110 GeV where Z-boson production dominates. No significant resonant peaks are observed, and limits are set on ε2 at 90% confidence as a function of the ZD mass (figure 2). These are among the world’s most stringent constraints on dark photons in this mass range.

    2
    Fig. 2. Upper limits on ε2 as a function of the ZD mass. Results obtained with data collected by the dimuon scouting triggers are to the left of the dashed line. Constraints from measurement of the electroweak observables are shown in light blue.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS

    CERN/ATLAS detector

    ALICE

    CERN/ALICE Detector


    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    LHC

    CERN map

    CERN LHC Grand Tunnel

    CERN LHC particles

     
  • richardmitnick 4:47 pm on January 9, 2020 Permalink | Reply
    Tags: "Department of Energy picks New York over Virginia for site of new particle collider", Accelerator Science, , , , , , ,   

    From BNL via Science Magazine: “Department of Energy picks New York over Virginia for site of new particle collider” 

    From Brookhaven National Lab

    via

    AAAS
    Science Magazine

    Jan. 9, 2020
    Adrian Cho

    Nuclear physicists’ next dream machine will be built at Brookhaven National Laboratory in Upton, New York, officials with the Department of Energy (DOE) announced today. The Electron-Ion Collider (EIC) will smash a high-energy beam of electrons into one of protons to probe the mysterious innards of the proton. The machine will cost between $1.6 billion and $2.6 billion and should be up and running by 2030, said Paul Dabbar, DOE’s undersecretary for science, in a telephone press briefing.

    6
    This schematic shows how the EIC will fit within the tunnel of the Relativistic Heavy Ion Collider (RHIC, background photo), reusing essential infrastructure and key components of RHIC.

    3
    Electrons will collide with protons or larger atomic nuclei at the Electron-Ion Collider to produce dynamic 3-D snapshots of the building blocks of all visible matter.

    7
    The EIC will allow nuclear physicists to track the arrangement of the quarks and gluons that make up the protons and neutrons of atomic nuclei.

    “It will be the first brand-new greenfield collider built in the country in decades,” Dabbar said. “The U.S. has been at the front end in nuclear physics since the end of the Second World War and this machine will enable the U.S. to stay at the front end for decades to come.”

    The site decision brings to a close the competition to host the machine. Physicists at DOE’s Thomas Jefferson National Accelerator Facility in Newport News, Virginia, had also hoped to build the EIC.

    Protons and neutrons make up the atomic nucleus, so the sort of work the EIC would do falls under the rubric of nuclear physics. Although they’re more common than dust, protons remain somewhat mysterious. Since the early 1970s, physicists have known that each proton consists of a trio of less massive particles called quarks. These bind to one another by exchanging other quantum particles called gluons.

    However, the detailed structure of the proton is far more complex. Thanks to the uncertainties inherent in quantum mechanics, its interior roils with countless gluons and quark-antiquark pairs that flit in and out of existence too quickly to be directly observed. And many of the proton’s properties—including its mass and spin—emerge from that sea of “virtual” particles. To determine how that happens, the EIC will use its electrons to probe the protons, colliding the two types of particles at unprecedented energies and in unparalleled numbers.

    Researchers at Jefferson lab already do similar work by firing their electron beam at targets rich with protons and neutrons. In 2017, researchers completed a $338 million upgrade to double the energy of the lab’s workhorse, the Continuous Electron Beam Accelerator Facility.

    3
    4
    Continuous Electron Beam Accelerator Facility

    With that electron accelerator in hand, Jefferson lab researchers had hoped to build the EIC by adding a new proton accelerator.

    Brookhaven researchers have studied a very different type of nuclear physics. Their Relativistic Heavy Ion Collider (RHIC) [below] collides nuclei such as gold and copper to produce fleeting puffs of an ultrahot plasma of free-flying quarks and gluons like the one that filled the universe in the split second after the big bang. The RHIC is a 3.8-kilometer-long ring consisting of two concentric and counter-circulating accelerators. Brookhaven researchers plan to make the EIC by using one of the RHIC’s rings to accelerate the protons and to add an electron accelerator to the complex.

    To decide which option to take, DOE officials convened an independent EIC site selection committee, Dabbar says. The committee weighed numerous factors, including the relative costs of the rival plans, he says. Proton accelerators are generally larger and more expensive than electron accelerators.

    The Jefferson lab won’t be left out in the cold, Dabbar says. Researchers there have critical expertise in, among other things, making the superconducting accelerating cavities that will be needed for the new collider. So, scientists there will participate in designing, building, and operating the new collider. “We certainly look forward to [the Jefferson lab] taking the lead in these areas,” Dabbar says.

    The site decision does not commit DOE to building the EIC. The project must still pass several milestones before researchers can being construction—including the approval of a detailed design, cost estimate, and construction schedule. That process can take a few years. However, the announcement does signal the end for the RHIC, which has run since 1999. To make way for the new collider, the RHIC will shut down for good in 2024, Dabbar said at the briefing.

    The decision on a machine still 10 years away reflects the relative good times for DOE science funding, Dabbar says. “We’ve been able to start on every major project that’s been on the books for years.” DOE’s science budget is up 31% since 2016—in spite of the fact that under President Donald Trump, the White House has tried to slash it every year.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 10:57 am on January 9, 2020 Permalink | Reply
    Tags: "New open release allows theorists to explore LHC data in a new way", Accelerator Science, , , , , , The first open release of full analysis likelihoods from an LHC experiment.   

    From CERN ATLAS: “New open release allows theorists to explore LHC data in a new way” 

    CERN/ATLAS detector

    CERN ATLAS Higgs Event

    CERN ATLAS another view Image Claudia Marcelloni ATLAS CERN

    From CERN ATLAS

    9 January, 2020
    Katarina Anthony

    The ATLAS collaboration releases full analysis likelihoods, a first for an LHC experiment.

    1
    Explore ATLAS open likelihoods on the HEPData platform. (Image: CERN)

    What if you could test a new theory against LHC data? Better yet, what if the expert knowledge needed to do this was captured in a convenient format? This tall order is now on its way from the ATLAS collaboration, with the first open release of full analysis likelihoods from an LHC experiment.

    “Likelihoods allow you to compute the probability that the data observed in a particular experiment match a specific model or theory,” explains Lukas Heinrich, CERN research fellow working for the ATLAS Experiment. “Effectively, they summarise every aspect of a particular analysis, from the detector settings, event selection, expected signal and background processes, to uncertainties and theoretical models.” Extraordinarily complex and critical to every analysis, likelihoods are one of the most valuable tools produced at the LHC experiments. Their public release will now enable theorists around the world to explore ATLAS data in a whole new way.

    The ATLAS open likelihoods are available on HEPData, an open-access repository for experimental particle physics data. The first open likelihoods released were for a search for supersymmetry in proton–proton collision events containing Higgs bosons, numerous jets of b-quarks and missing transverse momentum. “While ATLAS had published likelihood scans focused on the Higgs boson in 2013, those did not expose the full complexity of the measurements,” says Kyle Cranmer, Professor at New York University. “We hope this first release – which provides the full likelihoods in all their glory – will form a new communication bridge between theorists and experimentalists, enriching the discourse between the communities.”

    The search for new physics will benefit significantly from open likelihoods. “If you’re a theorist developing a new idea, your first question is likely: ‘Is my model already excluded by experiments at the LHC?’” says Giordon Stark, postdoctoral scholar at SCIPP, UC Santa Cruz. “Until now, there was no easy way to answer this.”

    2
    Likelihoods are an essential link between theory and ATLAS data. (Image: K. Cranmer/ATLAS)

    “We plan to make the open release of likelihoods a regular part of our publication process, and have already made them available from a search for the direct production of tau slepton pairs,” says Laura Jeanty, ATLAS Supersymmetry working group convenor. “Over the coming months, we aim to collect feedback from theorists outside the collaboration to best understand how they are using this new resource to further refine future releases.”

    Read more on the ATLAS website.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    CERN Courier

    Quantum Diaries
    QuantumDiaries

    CERN map


    CERN LHC Grand Tunnel
    CERN LHC particles

     
  • richardmitnick 10:25 am on December 20, 2019 Permalink | Reply
    Tags: Accelerator Science, , , eRHIC- electron-ion collider, , ,   

    From Brookhaven National Lab: “The Big Questions: Barbara Jacak on the Quark-Gluon Plasma” 

    From Brookhaven National Lab

    December 16, 2019
    Shannon Brescher Shea
    shannon.shea@science.doe.gov

    The PHENIX detector [below] at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider (RHIC) [below] records many different particles emerging from RHIC collisions, including photons, electrons, muons, and quark-containing particles called hadrons.

    The Big Questions series features perspectives from the five recipients of the Department of Energy Office of Science’s 2019 Distinguished Scientists Fellows Award describing their research and what they plan to do with the award.

    Contributing Author Credit: Barbara Jacak is the director of the nuclear science division at Lawrence Berkeley National Laboratory.

    What was matter like at the beginning of the universe?

    While we can’t time travel, we can explore the first microsecond after the Big Bang by re-creating the quark-gluon plasma. The very earliest type of matter, the quark-gluon plasma is a hot, incredibly dense soup of particles. These days, we produce the quark-gluon plasma by smashing heavy ions together at extremely high speeds.

    When we turned on the Relativistic Heavy Ion Collider (RHIC) [below] at Brookhaven National Laboratory in 2000, we found out that the quark-gluon plasma is much more interesting than we expected. It behaved like a liquid! How can something so hot – trillions of degrees kelvin – behave like a liquid? Even at that temperature, the strong interactions remain really strong.

    What we’re learning about the quark-gluon plasma can also teach us a lot about other types of plasma. The way it behaves isn’t all that different from the warm dense matter that makes up the cores of small stars and giant planets. Our work can even inform fusion scientists’ research to minimize disruptions in plasma. There’s a lot of room for cross-fertilization.

    RHIC, a Department of Energy Office of Science user facility, makes it possible to explore this unique form of matter. It relies on accelerators, extremely powerful machines that speed very tiny particles up to nearly the speed of light.

    The Office of Science – particularly the Nuclear Physics program – is a major steward of fundamental physics and accelerator science. Developing and maintaining accelerators has always been a major responsibility of the DOE national laboratories. E.O. Lawrence’s vision in the 1930s of the first circular accelerator both launched this field of research and the laboratory that eventually became DOE’s Lawrence Berkeley National Laboratory.

    2
    The first cyclotron, a particle accelerator created in 1930 at the University of California, Berkeley. (Lawrence Berkeley National Laboratory Photo Archives)

    But the government’s support for Lawrence’s invention was just the beginning. Even now, reliable long-term funding allows us to do great things that we wouldn’t be able to do with inconsistent support. Personally, the sustained support from the Office of Science that I’ve enjoyed has been truly awesome.

    Team science is also really fun. It makes us more productive and inspired. Fortunately, the Office of Science’s long-term support sets the foundation for the mentoring and growth of young scientists that go on to be researchers, innovators, and technological leaders. A student’s response when encountering the research at our national labs is, “This is awesome.” These young minds bring new ideas and questions that make us rethink how we look at fundamental problems. You can do stuff at the national labs that you can’t do anywhere else, but when you add students, that’s when the magic really happens. The combination makes the labs and the universities both better at their mission.

    Looking forward, the electron-ion collider will be the next great project coming out of this long-term support.

    3
    A schematic of the world’s first electron-ion collider (EIC). Adding an electron ring (red) to the Relativistic Heavy Ion Collider (RHIC) at Brookhaven would create the eRHIC.

    My team and I will be using it to discover some fundamental truths about protons, neutrons, and nuclei. I look forward to the adventures it will make possible. This includes writing some 21st century just-so stories, like “How the proton got his spin” and “How the neutron got her mass.”

    This fellowship is going to allow me and my team to use the electron-ion collider to see if the very interesting and weird properties that we see in hot dense matter full of gluons also show up in cold, dense matter full of gluons. My bet is that it’s going to be just as weird and surprising as hot dense matter.

    Thank you very much to the Department of Energy’s Office of Science for making my past, present, and future work possible.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX Detector

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 12:18 pm on December 16, 2019 Permalink | Reply
    Tags: "20th Year of Particle Smashups Underway at Relativistic Heavy Ion Collider", Accelerator Science, , , , ,   

    From Brookhaven National Lab: “20th Year of Particle Smashups Underway at Relativistic Heavy Ion Collider” 

    From Brookhaven National Lab

    December 16, 2019
    Karen McNulty Walsh
    kmcnulty@bnl.gov
    (631) 344-8350, or

    Peter Genzer
    genzer@bnl.gov
    (631) 344-3174

    Second of three-year program exploring the nuclear phase diagram at different collision energies to search for “critical point”.

    1
    The STAR detector at the Relativistic Heavy Ion Collider (RHIC).

    The 20th year of particle collisions is underway at the Relativistic Heavy Ion Collider (RHIC) [below], a U.S. Department of Energy Office of Science user facility for nuclear physics research at Brookhaven National Laboratory. The particle smashups will continue over a range of collision energies through the first half of 2020, with members of RHIC’s STAR collaboration collecting data from millions of collisions that take place at the center of their house-sized particle detector.

    The main goal of this RHIC run is to explore details of how the hot, dense soup of particles that existed just after the Big Bang—known as quark-gluon plasma—transitioned into the protons and neutrons that make up the bulk of visible matter in today’s world.

    “This will be the second in a three-year campaign to scan the phase diagram of hot matter governed by quantum chromodynamics (QCD), the theory that describes the interactions of quarks and gluons,” said Jamie Dunlop, Associate Chair for Nuclear Physics in Brookhaven Lab’s Physics Department. The range of collision energies over the three years will allow nuclear physicists to search for telltale signs of what’s called a critical point—a change in the way the transition from quarks and gluons to ordinary matter takes place.

    “Since RHIC collides only matter (gold on gold nuclei, and not gold on ‘anti-gold’ nuclei), at lower and lower beam energies the ‘little bangs’ we create in the collider are seeded with more and more matter than antimatter,” Dunlop said. “Past a certain point, this seeding is expected to change the nature of the phase transition between the quark-gluon plasma and normal matter from a smooth, continuous crossover (with no pause at a particular ‘temperature’ while the transition takes place), to a first-order phase transition (like steam to water, in which both phases coexist at 100 degrees Celsius until every molecule has condensed). By reducing the energy, we are searching for the point at which this change happens—the critical point.”

    To achieve these goals, Brookhaven’s accelerator physicists will deliver beams at lower energies than in last-year’s run, explained Wolfram Fischer, Associate Chair for Accelerators in Brookhaven’s Collider-Accelerator Department.

    “Last year, we ran the machine at 19.6 billion electron volts (GeV) and 14.6 GeV in two run sequences,” Fischer said. “This year we will run at 11.5 GeV and 9.1 GeV. That’s lower than the energy at which beams are normally injected into RHIC, and the machine was not really built for this regime, which will make operations quite challenging.”

    The most difficult challenge is that the tightly bunched ions tend to heat up and spread out as they circulate around RHIC’s 2.4-mile-circumference accelerator rings.

    “If the particles spread out, the likelihood of collisions diminishes,” Fischer said.

    Fortunately, last year, RHIC physicists successfully implemented a new component of the accelerator designed to cool the low-energy beams to maximize collision rates at these energies. This system brings accelerated “cool” electrons into a section of each RHIC ring to extract heat from the circulating ions.

    “This is somewhat similar to the way the liquid running through your home refrigerator extracts heat to keep your food cool,” Fischer said. “But the technology needed to achieve this beam cooling is quite a bit more complicated. It required a number of ‘world’s first’ advances, which our team achieved in last year’s demonstration.”

    With the Low Energy RHIC electron Cooling (LEReC) system fully implemented this year, the result should be more tightly packed ion bunches that result in more collisions—and more data—when the counter-circulating ion beams cross.

    “The second half of RHIC Run 20, in particular, depends on this cooling process, because that’s when the lowest-energy collisions will take place,” Fischer said. “Using low energy cooling will be another accomplishment that showcases the versatility of RHIC, a machine that has accomplished so much beyond the capabilities for which it was initially designed.”

    Said Dunlop, “We’re really looking forward to compiling the data from the three years of Beam Energy Scan II to greatly enhance our understanding of the phases of nuclear matter.”

    Research at RHIC is funded primarily by the DOE Office of Science.

    3
    Components of the Low Energy RHIC electron Cooling (LEReC) system will keep particle beams tightly packed to maximize collision rates at low energies.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 11:40 am on December 14, 2019 Permalink | Reply
    Tags: Accelerator Science, , Femtoscopy, , Hyperons, , , ,   

    From Symmetry: “Neutron star particles go under the LHC microscope” 

    Symmetry Mag
    From Symmetry<

    12/12/19
    Mordechai Rorvig

    1
    NASA/CXC/SAO

    Researchers on the ALICE experiment are uncovering the properties of elusive hyperon particles hypothesized to be found inside neutron stars.

    CERN/ALICE Detector

    Scientists know a thing or two about neutron stars, the compacted remains of massive stars that have burned out.

    They know that they’re about 95% made up of neutrons. They know that they’re generally 13 to 16 miles in diameter. Scientists know that, even though neutron stars are a thousandth the size of the Earth, they’re more massive than the sun. And the closest one they know of is about 500 light-years away.

    There’s also a lot they don’t know.

    “Neutron stars are the most dense objects in the universe,” says Laura Fabbietti, a physicist on the ALICE experiment and a professor at Technische Universität München in Germany. “And we don’t know what’s inside because we cannot fly there and look inside.”

    But scientists at CERN have found a way to learn more about the interior of neutron stars from a location that is much safer and easier to access: the Large Hadron Collider, right here on Earth.

    CERN/LHC Map

    Formed under pressure

    For neutron stars, gravity becomes extremely strong, approaching that of black holes. The force of it packs their matter down to high density.

    Neutron stars must be composed of matter that can withstand this pressure. And nature rearranges any matter that can’t into new matter that can.

    Iron, for example, is thought to be a component of the neutron star’s crust, where the pressure is lightest. Slightly deeper in, scientists think that iron atoms get crushed into heavier atoms. Even deeper, the electrons and protons that hold together atoms get crushed into neutrons. In the very interior of the star, those neutrons might get crushed into particles called hyperons.

    Hyperons are akin to heavier versions of neutrons, both of which are composed of quarks.

    Standard Model of Particle Physics

    There are six types of quarks in total. Most of the matter humans interact with, except for electrons, is built with the lightest of these quarks: up and down quarks. Neutrons, for example, are made of one up quark and two down quarks.

    The next heaviest quark is called the strange quark. Replacing an up or down quark in a neutron with a heavier strange quark yields a hyperon.

    Luckily for scientists who want to study this form of matter, all the different kinds of hyperons—different combinations of up, down and strange quarks—are produced in collisions in the Large Hadron Collider.

    Their lives are different there. In experiments at the LHC, hyperons last for less than a billionth of a second before decaying into other, lighter particles. In neutron stars, however, hyperons should be stable. Because they would be pressed in so close together, there would be no room for their decay products to form.

    Their short laboratory lifespans have made hyperons historically difficult to identify and study. But the unique capabilities of the ALICE detector at the LHC allowed Fabbietti and her research team to accurately identify the hyperon decay products and track those products back to their hyperon source. An upgrade of the ALICE detector will soon allow researchers to collect even more hyperon data.

    “We’re hungry for statistics, hungry for data,” says Bernhard Hohlweger, who led analysis to identify the Xi- (pronounced zai-minus) hyperon, a hyperon with a negative electric charge. “We use everything we can get our hands on.”

    Moving in pairs

    Fabbietti’s group didn’t want just to find hyperons, though; they wanted to learn more about what they do. If they could understand hyperon motion in the ALICE detector, then they could hypothesize the way that hyperons might behave while inaccessibly buried in the universe’s densest stars.

    The chief unknown for the ALICE researchers was the way that hyperons interact with the strong force, which binds quarks together and controls particle motion at small scales. Each kind of hyperon has its own unique mathematical function called a “potential” that explains how the hyperon interacts with the strong force to move.

    “For different particle interactions, there are different potentials,” says Anthony Timmins, a member of the ALICE collaboration and a professor at the University of Houston. Timmins recently presented results on proton Xi- hyperon interactions at the annual Division of Particles & Fields meeting in Boston in July.

    To figure out the Xi- hyperon potential, Fabbieti’s group first looked at a different kind of particle that comes from collisions in the LHC: the proton. Protons have never been observed to decay like short-lived LHC hyperons—and may not decay at all—making them easier to understand by comparison. On top of that, researchers already knew the proton potentials, and that those potentials cause protons to attract or repel each other based on how far apart they are.

    The scientists observed that pairs of protons coming out of collisions tend to be pulled into parallel trajectories by their strong-force potentials. They used that observation and a method called femtoscopy to infer the approximate size of the particles’ collision zone.

    Using femtoscopy, which relates particle motions and particle potentials to the size of collision zones, is like watching debris fly out of an explosion to figure out how big an explosive device must have been. (Only in this case, the debris also interact through the strong force.)

    Having analyzed the proton pairs, the researchers then looked at pairs of protons and hyperons coming out of particle collisions. They again observed parallel motions, indicating an attractive strong-force potential at work. Because they knew the size of the collision zone from the proton pairs, the they could solve for the only unknown: the hyperon potential.

    To understand and quantify this measured potential, next they needed a prediction from theory.

    Stiffening stars

    As it turned out, scientists had recently predicted what these potentials would be. They did it theoretically through simulations of quarks.

    These simulation models are general in nature, relying only on knowledge of quarks, with no specific customizations for the LHC experiments. To the researchers’ surprise and excitement, the simulation results and the measurements from Fabbietti’s group matched.

    “If we do some honest calculations and we get the result, then this result should be realized in nature,” says Tetsuo Hatsuda, a program director at the RIKEN institute in Japan, who helped lead the simulation program. And in this case, “the result was realized in nature.”

    Using these precisely calculated potentials, Takashi Inoue from Hatsuda’s HAL QCD collaboration showed how Xi- hyperons should interact with neutrons in neutron star matter. Hyperons and neutrons were found to repel, unlike hyperons and protons measured in the ALICE detector. This repulsion would make neutron stars stiffer and more resistant to gravitational forces if hyperons were present.

    The baton now goes to astrophysicists, who can compare predicted neutron star stiffness with their observations to help answer the question whether hyperons do indeed exist inside stars.

    Fabbietti and her group plan to continue analyzing more data for different kinds of hyperons, with better precision. Fabbietti says that now “this is a factory of results,” results that show how the 17-mile, underground ring of the LHC can act as a microscope into the stars.

    See the full article here .


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

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: