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  • richardmitnick 11:16 am on May 7, 2021 Permalink | Reply
    Tags: "Exploring the strong interaction in the universe", , , Particle Physics,   

    From GSI Helmholtz Centre for Heavy Ion Research [GSI Helmholtz Zentrum für Schwerionenforschung] GmbH (DE): “Exploring the strong interaction in the universe” 

    GSI Helmholtz Centre for Heavy Ion Research GmbH, Darmstadt, Germany (DE),

    From GSI Helmholtz Centre for Heavy Ion Research [GSI Helmholtz Zentrum für Schwerionenforschung] GmbH (DE)

    05.04.2021

    1
    Achim Schwenk, Professor of Physics at the Technical University of Darmstadt [Technische Universität Darmstadt] (DE) and Max Planck Fellow at the MPG Institute for Nuclear Physics [MPG Institut für Kernphysik] (DE) in Heidelberg, has been awarded a prestigious Advanced Grant by the European Research Council (ERC). His research project Exploring the Universe through Strong Interactions (EUSTRONG) will be funded with around 2.3 million euros over a period of five years. This is already the second ERC grant for Professor Schwenk.

    The goal of the EUSTRONG project is to explore the Strong Interaction, one of the four fundamental forces of nature, in the Universe. The Strong Interaction is responsible for holding neutrons and protons together in the atomic nucleus and for understanding the densest observable matter inside neutron stars. In addition, atomic nuclei play a key role in the search for dark matter and in the study of the lightest neutrino particles. EUSTRONG will enable new discoveries in the physics of the Strong Interaction by developing innovative theories and methods.

    The equation of state of dense nuclear matter, for example, sets the scale for the mass and radius of neutron stars. At extreme densities beyond those achieved in atomic nuclei, astrophysical observations are particularly interesting. For example, information about the radius of neutron stars, which is sensitive to high densities, can be obtained from LIGO/Virgo observations of gravitational waves from neutron star mergers, as well as from new observations with NASA’s NICER instrument on the International Space Station.

    Caltech/MIT Advanced aLigo at Hanford, WA(US), Livingston, LA(US) and VIRGO Gravitational Wave interferometer, near Pisa(IT).

    “So far, this fits very well with our understanding about the equation of state of nuclear matter,” explains Professor Schwenk. “With EUSTRONG, we want to for the first time derive direct constraints on the dense-matter interactions from these astrophysical observations, and thus develop a unified description of matter in nuclei and stars.”

    Another milestone of the ERC project is the acceleration of many-body calculations with new emulation and network methods to enable systematic and global ab initio calculations based on the Strong Interaction for heavy nuclei. One focus are extremely neutron-rich heavy nuclei (around neutron number 126), which play a central role in the synthesis of elements in the Universe. The accelerator facility FAIR (Facility for Antiproton and Ion Research: FAIR (DE) ) in Darmstadt will be leading in this region of the nuclear chart.

    Based on these new developments, Professor Schwenk and his team also want to investigate key nuclei that are used in extremely sensitive detectors that search for dark matter and for the discovery of coherent neutrino scattering, which was recently achieved for the first time. In the exploration of dark matter in the Universe and of new physics beyond the Standard Model, the Strong Interaction therefore also plays an essential role.

    “The second award by the ERC underlines how outstanding Professor Achim Schwenk’s research achievements are,” emphasizes Professor Barbara Albert, Vice President for Research and Young Scientists at TU Darmstadt. Professor Schwenk is particularly excited to be working with excellent young scientists in the new EUSTRONG team, “because the conditions in nuclear physics are unique here and the students and postdocs are great”. (TUD/CP)

    See the full article here.

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    GSI Helmholtz Centre for Heavy Ion Research GmbH, Darmstadt, Germany (DE),

    GSI Helmholtz Centre for Heavy Ion Research [GSI Helmholtz Zentrum für Schwerionenforschung] GmbH (DE) is a federally and state co-funded heavy ion (Schwerion [de]) research center in the Wixhausen suburb of Darmstadt, Germany. It was founded in 1969 as the Society for Heavy Ion Research (German: Gesellschaft für Schwerionenforschung), abbreviated GSI, to conduct research on and with heavy-ion accelerators. It is the only major user research center in the State of Hesse.

    The laboratory performs basic and applied research in physics and related natural science disciplines. Main fields of study include plasma physics, atomic physics, nuclear structure and reactions research, biophysics and medical research. The lab is a member of the Helmholtz Association of German Research Centres [Helmholtz-Gemeinschaft Deutscher Forschungszentren] (DE).

    Shareholders are the German Federal Government (90%) and the State of Hesse, Thuringia and Rhineland-Palatinate. As a member of the Helmholtz Association, the current name was given to the facility on 7 October 2008 in order to bring it sharper national and international awareness.[1]

    The GSI Helmholtz Centre for Heavy Ion Research has strategic partnerships with the Technical University of Darmstadt [Technische Universität Darmstadt](DE), Goethe University Frankfurt [Goethe-Universität](DE), Johannes Gutenberg University Mainz [Johannes Gutenberg-Universität Mainz](DE)and the Frankfurt Institute for Advanced Studies.

     
  • richardmitnick 1:44 pm on May 6, 2021 Permalink | Reply
    Tags: "LS2 Report: FASER is born", , , , FASER is designed to study the interactions of high-energy neutrinos and search for new as-yet-undiscovered light and weakly interacting particles., , , Particle Physics,   

    From European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(EU) [CERN]: “LS2 Report: FASER is born” 

    Cern New Bloc

    Cern New Particle Event

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

    24 March, 2021 [Just now in social media.]
    Anaïs Schaeffer

    1
    The final elements of FASER were put into place this month. (Image: CERN)

    FASER* (Forward Search Experiment), CERN’s newest experiment, is now in place in the LHC tunnel, only two years after its approval by CERN’s Research Board in March 2019. FASER is designed to study the interactions of high-energy neutrinos and search for new as-yet-undiscovered light and weakly interacting particles. Such particles are dominantly produced along the beam collision axis and may be long-lived particles, travelling hundreds of metres before decaying. The existence of such new particles is predicted by many models beyond the Standard Model that attempt to solve some of the biggest puzzles in physics, such as the nature of dark matter and the origin of neutrino masses.

    FASER is located along the beam collision axis, 480 m from the ATLAS interaction point, in an unused service tunnel that formerly connected the SPS to the LEP collider – an optimal position for detecting the particles into which light and weakly interacting particles will decay.

    The first civil engineering works started in May 2020. “Because of the sloped geometry of the tunnel, the beam collision axis was actually passing under the ground,” says Jamie Boyd, FASER co-spokesperson. “Measurements from the CERN survey team showed that, by excavating a 50-cm-deep trench, sufficient space would be created to house the 5-m-long FASER detector.” In the summer, the first services and power systems were installed, and in November, FASER’s three magnets were put in place in the trench.

    2
    The installation of FASER’s three magnets took place in November, in the narrow trench excavated by CERN’s SCE team. (Image: CERN)

    A pretty simple experiment
    At the entrance to the detector, two scintillator stations are used to veto charged particles coming through the cavern wall from the ATLAS interaction point; these are primarily high-energy muons. The veto stations are followed by a 1.5-m-long dipole magnet. This is the decay volume for long-lived particles decaying into a pair of oppositely charged particles. After the decay volume is a spectrometer consisting of two 1-m-long dipole magnets with three tracking stations, which are located at either end and in between the magnets. Each tracking station is composed of layers of precision silicon strip detectors. Scintillator stations for triggering and precision time measurements are located at the entrance and exit of the spectrometer.

    The final component is the electromagnetic calorimeter. This will identify high-energy electrons and photons and measure the total electromagnetic energy. The whole detector is cooled down to 15 °C by an independent cooling station.

    “FASER uses spare pieces from the ATLAS (for the tracker) and LHCb (for the calorimeter) experiments, which made possible its installation during Long Shutdown 2, so quickly after its approval,” highlights Jamie Boyd.

    FASER will also have a subdetector called FASERν, which is specifically designed to detect neutrinos. No neutrino produced at a particle collider has ever been detected, despite colliders producing them in huge numbers and at high energies. FASERν is made up of emulsion films and tungsten plates to act as both the target and the detector to see the neutrino interactions. FASERν should be ready for installation by the end of the year. The whole experiment will start taking data during Run 3 of the LHC, starting in 2022.

    “We are extremely excited to see this project come to life so quickly and smoothly,” says Jamie Boyd. “Of course, this would not have been possible without the expert help of the many CERN teams involved!”

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

    See the full article here.


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier


    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS

    ALICE

    CMS

    LHCb

    LHC

    OTHER PROJECTS AT CERN

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

     
  • richardmitnick 9:06 am on May 6, 2021 Permalink | Reply
    Tags: "The superconducting coils for the 11T dipoles have been delivered", , , CERN (CH) Accelerating News, , , Particle Physics,   

    From CERN (CH) Accelerating News : “The superconducting coils for the 11T dipoles have been delivered” 

    From CERN (CH) Accelerating News

    28 April, 2021
    Anaïs Schaeffer (European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(CH) [CERN])

    35 niobium–tin superconducting coils have been manufactured as part of a fruitful collaboration with the company General Electric. They will be used in the 11 T dipoles for the HL-LHC.

    1
    Control samples fitted to the ends of the niobium–tin coils’ heat-treatment mould to check the conformity of the electrical performance. (Image: CERN).

    Starting in 2018, a team of experts from the company General Electric (GE) worked with the Magnets, Superconductors and Cryogenics (TE-MSC) group at CERN to manufacture superconducting coils for the new 11 T dipoles being developed for the HL-LHC project. In January, following three years of fruitful collaboration, the 15-strong team left the Laboratory.

    The 11 T dipoles are based on superconducting niobium–tin (Nb3Sn). They are just six metres long but, thanks to their higher field, they might be able to replace some of the main 15-metre-long LHC dipoles in strategic parts of the accelerator, notably at Point 7, freeing up space for new collimators. The plan is to install a total of four 11 T dipoles for the HL-LHC.

    “From the very beginning, we established a relationship of trust between the CERN and GE teams to ensure knowledge transfer and cross-fertilisation,” explains Arnaud Devred, leader of the Magnets, Superconductors and Cryogenics group. “We have learned from their industrial approach and their organisational structure, using production units, which has helped us to improve our quality assurance. As for GE, they have developed specific skills in the manufacture of superconducting magnets thanks to their work on the 11 T dipoles, a new technology that is still evolving.”

    A total of 35 coils have been manufactured and assembled in the Large Magnet Facility on the Meyrin site, using tools provided by CERN. They will form part of the 11 T dipoles, which may be installed in the LHC during a future technical stop.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    CERN (CH) Accelerating News is a quarterly online publication for the accelerator community.
    ISSN: 2296-6536

    The publication showcases news and results from the biggest accelerator research and development projects such as ARIES, HL-LHC, TIARA, FCC study, EuroCirCol, EUPRAXIA, EASITrain as well as interesting stories on other accelerator applications. The newsletter also collects upcoming accelerator research conferences and events.

    Accelerating News is published 4 times a year, in mid March, mid June, mid September and mid December.

    You can read Accelerating News via the homepage http://www.acceleratingnews.eu or by email.

    To subscribe to Accelerating News, enter your email in the “Subscribe to our newsletter” box in the footer.

    History

    Accelerating News evolved from the EuCARD quarterly project newsletter (see past issues), which was first published in June 2009 to a subscription list of approximately 200. Initiated by EuCARD and in collaboration with additional FP7 co-funded projects, the first edition of Accelerating News was published in April 2012 to an initial distribution list of about 800 subscribers. Currently more than 1750 members receive the quarterly issues.

     
  • richardmitnick 8:52 am on May 6, 2021 Permalink | Reply
    Tags: "Accelerators probing Gravitational Waves", , , CERN Future Circular Collider (FCC), Chinese Circular Electron Positron Collider (CEPC), European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(CH) [CERN] Accelerating News, , , Particle Physics,   

    From European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(CH) [CERN] Accelerating News : “Accelerators probing Gravitational Waves” 

    From European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(CH) [CERN] Accelerating News

    8 April, 2021 [Just now in social media.]
    Giuliano Franchetti (GSI Helmholtz Centre for Heavy Ion Research [GSI Helmholtzzentrum für Schwerionenforschung] (DE))
    Marco Zanetti (National Institute for Nuclear Physics [Istituto Nazionale di Fisica Nucleare] – Padova Unit (IT))
    Frank Zimmermann

    1

    After the discovery of gravitational waves (GWs) by the LIGO detector in 2015, and with the advent of proposals for new large storage rings such as the 100 km CERN Future Circular Collider (FCC) or Circular Electron Positron Collider (CEPC), the question whether accelerators can be used for the detection or generation of GWs has gained new importance and urgency.

    In February and March 2021, a topical virtual workshop “Storage Rings and Gravitational Waves” (SRGW2021) [1], organized in the frame of the H2020 project ARIES, shed new light on this tantalizing possibility. More than 100 accelerator experts, particle physicists and members of the gravitational physics community jointly explored possible novel directions of accelerator research.

    After Jorge Cervantes (National Institute for Nuclear Research [Instituto Nacional de Investigaciones Nucleares] (MX)) presented a vivid account of the history of gravitational waves, Bangalore S. Sathyaprakash (Pennsylvania State University (US) and Cardiff University (UK)) reviewed the main sources of gravitational waves expected. The GW frequency range of interest extends from 0.1 nHz to 1 MHz. Raffaele Flaminio (LAPP-Annecy Laboratory of Particle Physics [Laboratoire d’Annecy de Physique des Particules] (FR)) described the extreme precision of the VIRGO and LIGO light-interferometers, while Jörg Wenninger (European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(EU)) reported the impressive sensitivity of large lepton or hadron storage rings – LEP and LHC – to small effects, such as the tides or earthquakes elsewhere.

    A gravitational wave can resonantly interact with either the transverse betatron motion of a stored particle beam at a frequency of several kHz, or with the longitudinal synchrotron motion at a frequency of 10s of Hz. Katsunobu Oide (KEK [高エネルギー加速器研究機構](JP) and CERN) discussed the betatron resonances excited by GWs, and proposed special beam-optical insertions, serving as “gravitational-wave antennas”, to enhance the resonance strength. Suvrat Rao (University of Hamburg [Universität Hamburg] (DE)) discussed the longitudinal beam response [2]. This response is enhanced for perturbations close to the synchrotron frequency. Raffaele D’Agnolo (Institute of Theoretical Physics [Institut de Physique Théorique] (FR)) estimated the sensitivity to the gravitational strain h, without any backgrounds, as h~10-13, and suggested three possible paths to further improve the sensitivity.

    Figure 2 superimposes ideal sensitivity curves from revolution time at the LHC and from the transverse resonant response for a storage ring with GW antenna optics, along with expected sources, in the strain-frequency plane.

    2
    Ideal noise-free GW sensitivity at the LHC for 1 ps resolution in revolution time (red curve, Suvrat Rao, from [2]) and ideal transverse resonant betatron response sensitivity of a 37 km ring with GW-antenna optics under two different assumptions for the beam-position measurement resolution (green and blue curves, Katsunobu Oide and Frank Zimmermann), in the strain-frequency plane, superimposed on a picture of expected sources taken from http://gwplotter.com/. Also shown is the predicted strength of the LHC as a gravitational source for the coherent emission of gravitational synchrotron radiation, assuming all protons in a beam are contributing coherently (red star, Pisin Chen). All three storage-ring lines and the marker require confirmation. (Image: CERN).

    Workshop participants discussed possible coasting beam experiments, and the sensitivity of heavy ions or of cold crystalline beams. Witek Krasny (LPNHE) suggested relying on “atomic clocks” as for the Gamma factory. Andrey Ivanov (TU Vienna) discussed the possible shrinking of storage ring circumferences under the influence of the relic GW microwave background [3].

    High-quality superconducting radiofrequency cavities could offer an alternative venue to detect gravitational waves, as presented by Sebastian Ellis (IPhT). Atomic beam interferometry is another promising approach, pursued by Oliver Buchmüller (Imperial College London (UK)) and John Ellis (King’s College London (UK)).

    Pisin Chen (NTU Taiwan) discussed how relativistic charged particles in a storage ring can emit gravitational waves [4]. If all particles and bunches excited the GW coherently the spacetime metric perturbation could be as large as hGSR~10-18 for the LHC, as indicated by a red start in Figure 2. This estimate requires further confirmation. John Jowett (GSI, retired from CERN) recalled that gravitational synchrotron radiation from the future LEP, LHC and SSC beams had been discussed at CERN in the late 1980. It was then realised that these beams would be among the most powerful terrestrial sources of gravitational radiation [5].

    The concluding workshop discussion was moderated by John Ellis (King’s College London).

    Gravitational waves are a unique tool to understand the today’s universe and to unravel its history. The great excitement and interest prompted by the ARIES SRGW2021 workshop, and the preliminary findings, call for further investigations.

    References

    [1] SRGW2021 workshop web site https://indico.cern.ch/event/982987
    [2] S. Rao et al. 2020 Phys. Rev. D 102, 122006
    [3] A. Ivanov et al. 2002 arxiv gr-qc/021009
    [4] P. Chen 1994 SLAC-PUB-6666 and 1995 Phys. Rev. Lett. 74, 634
    [5] G. Diambrini Palazzi et al., 1987 Phys. Lett. B 197, 302

    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 (CH) Accelerating News is a quarterly online publication for the accelerator community.
    ISSN: 2296-6536

    The publication showcases news and results from the biggest accelerator research and development projects such as ARIES, HL-LHC, TIARA, FCC study, EuroCirCol, EUPRAXIA, EASITrain as well as interesting stories on other accelerator applications. The newsletter also collects upcoming accelerator research conferences and events.

    Accelerating News is published 4 times a year, in mid March, mid June, mid September and mid December.

    You can read Accelerating News via the homepage http://www.acceleratingnews.eu or by email.

    To subscribe to Accelerating News, enter your email in the “Subscribe to our newsletter” box in the footer.

    History

    Accelerating News evolved from the EuCARD quarterly project newsletter (see past issues), which was first published in June 2009 to a subscription list of approximately 200. Initiated by EuCARD and in collaboration with additional FP7 co-funded projects, the first edition of Accelerating News was published in April 2012 to an initial distribution list of about 800 subscribers. Currently more than 1750 members receive the quarterly issues.

     
  • richardmitnick 6:35 am on May 6, 2021 Permalink | Reply
    Tags: "Searching for the Music of Dark Matter", , Employing many tabletop devices in labs across the world to find direct evidence for the mysterious dark matter., Particle Physics, Quantum optomechanics, University of Arizona (US)   

    From University of Arizona (US) : “Searching for the Music of Dark Matter” 

    From University of Arizona (US)

    5.5.21
    Resources for the media
    Mikayla Mace Kelley
    University Communications
    mikaylamace@arizona.edu
    520-621-1878

    Researcher contact(s)
    Dalziel Wilson
    James C. Wyant College of Optical Sciences
    dalziel@email.arizona.edu
    520-621-6997

    A University of Arizona optical scientist proposes repurposing existing tabletop technology in labs around the world to search for dark matter.

    1
    The illustration shows how a cavity optomechanical system is used as a dark matter sensor. The white dotted wave represents the dark matter signal. The arrow indicates that it pushes on the mirror, changing the length of the optical cavity. The length of the optical cavity is measured using an optical field, represented by the red wave. Credit: Dalziel Wilson.

    Scientists are certain dark matter exists, yet after more than 50 years of searching, they’re still unsure what it’s made of.

    Dalziel Wilson, a University of Arizona assistant professor in the James C. Wyant College of Optical Sciences, is senior author on a paper published in Physical Review Letters that describes a new way to look for the particles that might make up dark matter.

    1
    A rendering of the device Dalziel Wilson proposes to use in the search for dark matter. Credit: Dalziel Wilson.

    Wilson is an experimentalist in quantum optomechanics, and he makes mechanical devices and uses lasers to measure their response to stimuli at the quantum level. He is part of a small but growing group of scientists that think that by slightly reconfiguring optomechanics technology, they can make tabletop dark-matter detectors. By employing many of these devices in labs across the world they hope to find direct evidence for the mysterious matter.

    “The kind of device we want to use is called a nanomechanical resonator,” Wilson said. “You can think of it like a miniature turning fork. It’s a vibrating device, which, due to its small size, is very sensitive to perturbations from the environment.”

    Nanomechanical resonators have recently been used to detect and amplify weak signatures of the uncertainty principle in quantum mechanics, which says that the position and the velocity of an object cannot both be measured at the same time. Wilson and his peers reason that very weak signals produced by dark matter can also be detected and amplified using such devices.

    Wilson’s co-authors include UArizona optical sciences graduate student Mitul Dey Chowdhury, Haverford College (US)‘s Daniel Grin and the University of Delaware‘s Jack Manley and Swati Singh.

    Coming Together

    A few years ago, the dark matter community decided it was necessary to rethink how to look for dark matter. So, they teamed up with researchers in different fields, including optomechanics.

    If you add up all the things that emit light, such as stars, planets and interstellar gas, it only accounts for about 15% of the matter in the universe. The other 85% is known as dark matter. It doesn’t emit light, but researchers know it exists by its gravitational effects. They also know it isn’t ordinary matter, such as gas, dust, stars, planets and people, explained Singh, a quantum theorist and an alumnus of the UArizona College of Optical Sciences.

    “It could be made up of black holes, or it could be made up of something trillions of times smaller than an electron, known as ultralight dark matter,” Singh said.

    “It’s fruitful to come at these problems both ways – theoretically and experimentally,” Wilson said.

    Theorists say that dark matter might not only interact with ordinary matter gravitationally, but also via a “dark photon force,” but such interactions produce a very weak signal.

    Fortunately, Wilson is in the game of detecting and amplifying weak signals.

    His device, as described in his team’s experimental proposal, is a thin piece of silica nitride glass that is stretched into a drum. It’s 100 nanometers thick and a millimeter wide. Such extreme ratios of thinness to width make the drum very sensitive to inertial forces while at the same time decoupling it from other environmental disturbances.

    “It’s nanotechnology in the pursuit of quantum mechanics, coincidentally putting us in a regime where we can pursue dark matter searches,” Wilson said. “We’re not the first to realize this coincidence, but we’re among the first to propose a concrete detector design. The idea is that we can take a technology that we’ve been building in the field of optomechanics for a while and functionalize it to search for dark matter.”

    Wilson and Singh teamed up because they believe the idea applies to many types of devices, and different people could search with their favorite. The sensor might be a drum – like Wilson’s – or a string, a membrane, a levitated sphere, a cantilever or a pendulum.

    Searching for a dark matter signal won’t be easy, however. It will be like looking for a needle in a huge haystack.

    “We’re looking for that weak note, that little vibration,” Wilson said. “We want to take a mechanical resonator that resonates at the same frequency as the note, just like a tuning fork, then let it ring up. That note we want to play is extremely weak, so we want to listen for long enough that it rings up to a tangible amplitude and with many different devices.”

    But scientists don’t know exactly where to look, so they have to do what other people do when they search for dark matter, which is look at a certain frequency for a month, then change the tuning fork dimensions, look for another month and so on.

    “This paper is sort of a call to arms,” Wilson said. “Detecting dark matter is a daunting challenge. It’s like fishing in the middle of the ocean. You have no idea what’s biting or how deep the fish are, but the most important fish is the first; then you know what to look for. We just need to put enough lines in the water that we start to feel something.”

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    As of 2019, the University of Arizona (US) enrolled 45,918 students in 19 separate colleges/schools, including the UArizona College of Medicine in Tucson and Phoenix and the James E. Rogers College of Law, and is affiliated with two academic medical centers (Banner – University Medical Center Tucson and Banner – University Medical Center Phoenix). UArizona is one of three universities governed by the Arizona Board of Regents. The university is part of the Association of American Universities and is the only member from Arizona, and also part of the Universities Research Association(US). The university is classified among “R1: Doctoral Universities – Very High Research Activity”.

    Known as the Arizona Wildcats (often shortened to “Cats”), the UArizona’s intercollegiate athletic teams are members of the Pac-12 Conference of the NCAA. UArizona athletes have won national titles in several sports, most notably men’s basketball, baseball, and softball. The official colors of the university and its athletic teams are cardinal red and navy blue.

    After the passage of the Morrill Land-Grant Act of 1862, the push for a university in Arizona grew. The Arizona Territory’s “Thieving Thirteenth” Legislature approved the UArizona in 1885 and selected the city of Tucson to receive the appropriation to build the university. Tucson hoped to receive the appropriation for the territory’s mental hospital, which carried a $100,000 allocation instead of the $25,000 allotted to the territory’s only university (Arizona State University(US) was also chartered in 1885, but it was created as Arizona’s normal school, and not a university). Flooding on the Salt River delayed Tucson’s legislators, and by they time they reached Prescott, back-room deals allocating the most desirable territorial institutions had been made. Tucson was largely disappointed with receiving what was viewed as an inferior prize.

    With no parties willing to provide land for the new institution, the citizens of Tucson prepared to return the money to the Territorial Legislature until two gamblers and a saloon keeper decided to donate the land to build the school. Construction of Old Main, the first building on campus, began on October 27, 1887, and classes met for the first time in 1891 with 32 students in Old Main, which is still in use today. Because there were no high schools in Arizona Territory, the university maintained separate preparatory classes for the first 23 years of operation.

    Research

    UArizona is classified among “R1: Doctoral Universities – Very high research activity”. UArizona is the fourth most awarded public university by National Aeronautics and Space Administration(US) for research. UArizona was awarded over $325 million for its Lunar and Planetary Laboratory (LPL) to lead NASA’s 2007–08 mission to Mars to explore the Martian Arctic, and $800 million for its OSIRIS-REx mission, the first in U.S. history to sample an asteroid.

    The LPL’s work in the Cassini spacecraft orbit around Saturn is larger than any other university globally. The UArizona laboratory designed and operated the atmospheric radiation investigations and imaging on the probe. UArizona operates the HiRISE camera, a part of the Mars Reconnaissance Orbiter. While using the HiRISE camera in 2011, UArizona alumnus Lujendra Ojha and his team discovered proof of liquid water on the surface of Mars—a discovery confirmed by NASA in 2015. UArizona receives more NASA grants annually than the next nine top NASA/JPL-Caltech(US)-funded universities combined. As of March 2016, the UArizona’s Lunar and Planetary Laboratory is actively involved in ten spacecraft missions: Cassini VIMS; Grail; the HiRISE camera orbiting Mars; the Juno mission orbiting Jupiter; Lunar Reconnaissance Orbiter (LRO); Maven, which will explore Mars’ upper atmosphere and interactions with the sun; Solar Probe Plus, a historic mission into the Sun’s atmosphere for the first time; Rosetta’s VIRTIS; WISE; and OSIRIS-REx, the first U.S. sample-return mission to a near-earth asteroid, which launched on September 8, 2016.

    UArizona students have been selected as Truman, Rhodes, Goldwater, and Fulbright Scholars. According to The Chronicle of Higher Education, UArizona is among the top 25 producers of Fulbright awards in the U.S.

    UArizona is a member of the Association of Universities for Research in Astronomy(US), a consortium of institutions pursuing research in astronomy. The association operates observatories and telescopes, notably Kitt Peak National Observatory(US) just outside Tucson. Led by Roger Angel, researchers in the Steward Observatory Mirror Lab at UArizona are working in concert to build the world’s most advanced telescope. Known as the Giant Magellan Telescope(CL), it will produce images 10 times sharper than those from the Earth-orbiting Hubble Telescope.

    Giant Magellan Telescope, 21 meters, to be at the NOIRLab(US) National Optical Astronomy Observatory(US) Carnegie Institution for Science’s(US) Las Campanas Observatory(CL), some 115 km (71 mi) north-northeast of La Serena, Chile, over 2,500 m (8,200 ft) high.


    The telescope is set to be completed in 2021. GMT will ultimately cost $1 billion. Researchers from at least nine institutions are working to secure the funding for the project. The telescope will include seven 18-ton mirrors capable of providing clear images of volcanoes and riverbeds on Mars and mountains on the moon at a rate 40 times faster than the world’s current large telescopes. The mirrors of the Giant Magellan Telescope will be built at UArizona and transported to a permanent mountaintop site in the Chilean Andes where the telescope will be constructed.

    Reaching Mars in March 2006, the Mars Reconnaissance Orbiter contained the HiRISE camera, with Principal Investigator Alfred McEwen as the lead on the project. This National Aeronautics and Space Administration(US) mission to Mars carrying the UArizona-designed camera is capturing the highest-resolution images of the planet ever seen. The journey of the orbiter was 300 million miles. In August 2007, the UArizona, under the charge of Scientist Peter Smith, led the Phoenix Mars Mission, the first mission completely controlled by a university. Reaching the planet’s surface in May 2008, the mission’s purpose was to improve knowledge of the Martian Arctic. The Arizona Radio Observatory(US), a part of UArizona Department of Astronomy Steward Observatory(US), operates the Submillimeter Telescope on Mount Graham.

    The National Science Foundation(US) funded the iPlant Collaborative in 2008 with a $50 million grant. In 2013, iPlant Collaborative received a $50 million renewal grant. Rebranded in late 2015 as “CyVerse”, the collaborative cloud-based data management platform is moving beyond life sciences to provide cloud-computing access across all scientific disciplines.
    In June 2011, the university announced it would assume full ownership of the Biosphere 2 scientific research facility in Oracle, Arizona, north of Tucson, effective July 1. Biosphere 2 was constructed by private developers (funded mainly by Texas businessman and philanthropist Ed Bass) with its first closed system experiment commencing in 1991. The university had been the official management partner of the facility for research purposes since 2007.

    U Arizona mirror lab-Where else in the world can you find an astronomical observatory mirror lab under a football stadium?

    University of Arizona’s Biosphere 2, located in the Sonoran desert. An entire ecosystem under a glass dome? Visit our campus, just once, and you’ll quickly understand why the UA is a university unlike any other.

     
  • richardmitnick 5:11 pm on May 4, 2021 Permalink | Reply
    Tags: "What’s Inside Neutron Stars?", , , , , Neutron star J0030+0451, Neutron star J0470+6620, Particle Physics,   

    From Sky & Telescope : “What’s Inside Neutron Stars?” 

    From Sky & Telescope

    May 4, 2021
    Monica Young

    Size measurements of two neutron stars are narrowing down what kinds of exotic matter might exist in their extremely dense cores.

    Neutron stars are the tricksters of the celestial sphere. Their age, their temperature, even their size is not always what it first appears to be.

    But with the Neutron star Interior Composition Explorer (NICER) aboard the International Space Station, astronomers are finally beginning to make some headway measuring these stars’ actual size — and with that, some insight into their strange interiors.

    Members of the NICER team presented two independent size measurements of the most massive neutron star known at the recent virtual meeting of the American Physical Society.

    These studies, now undergoing scientific review, suggest that nuclear physicists might need to rethink what happens in the stars’ ultra-dense cores.


    NASA’s NICER Tests Matter’s Limits

    Matter at Its Most Extreme

    Neutron stars are the cinders left when massive stars implode, shedding their outer layers in supernova explosions. The stars are poised on the edge, just this side of collapsing into a black hole, and the immense gravitational pressure squeezes their electrons and protons into neutrons. Lifting a teaspoon of this matter would be a feat similar to drinking empty a horn attached to the ocean — even Thor could not lift 4 billion tons.

    However, there’s more to neutron stars than what’s in their name — they’re at most 95% neutrons and possibly even less. Their crystalline crusts contain relatively ordinary electrons and ions (the latter of which are made of neutrons and protons). As gravitational pressure increases with depth, the neutrons squeeze out of the nuclei, which eventually dissolve completely. Most protons merge with electrons; only a smattering remain for stability.

    2
    Neutron stars are not all neutrons — they likely have layers of different material. The state of matter in their inner cores remains unknown. NASA’s Goddard Space Flight Center (US) / Conceptual Image Lab

    Deeper still, in the core, the density reaches something like twice that of an atomic nucleus. Here, the matter may transform again, releasing even the quarks that make up neutrons.

    Or that’s what some theories say. But in fact nuclear physicists offer many answers to the riddle of neutron star interiors. “We have a theory for how quarks and gluons behave; this is quantum chromodynamics,” Miller says. “But the problem is you can’t really calculate this once you go past a couple of particles.” So nuclear physicists use approximations and assumptions to predict the behavior of lots of particles — and they come up with a variety of answers.

    To tell which idea is right, astronomers must do something deceptively simple: measure these objects’ mass and radius. From there they can use well-understood physics to calculate how pressure changes with density, a relation known as the equation of state, and then compare that equation to the nuclear physicists’ offerings.

    Neutrons, Quarks, or Hyperons?

    Obtaining the mass of a neutron star is easy, at least if the neutron star has a stellar companion whirling around it. But measuring size is trickier. Neutron stars’ gravity is so extreme, it bends the path of light leaving the surface. Like a funhouse mirror, this gravitational distortion makes the neutron star appear bigger than it really is.

    3
    A neutron star’s gravity warps nearby spacetime like a bowling ball resting on a trampoline. The distortion is strong enough that it redirects light from the star’s far side toward us, which makes the star look bigger than it really is.
    NASA’s Goddard Space Flight Center / Chris Smith (Universities Space Research Association (US) / NASA GESTAR [Goddard Earth Science Technology and Research] (US))

    Anna Watts (University of Amsterdam [Universiteit van Amsterdam] (NL)) and Cole Miller (University of Maryland (US)) lead two independent teams that analyze NICER data to see through this light-bending effect and put a ruler to neutron stars.

    NICER is designed to measure the rapidly changing brightness of neutron stars as they whirl around. Some of these city-size objects spin faster than the blades in a kitchen blender, but NICER can catch changes over time periods as short as 100 nanoseconds. Additional observations by the European Space Agency’s XMM-Newton telescope helped the teams understand the X-ray background and obtain more accurate results.

    The X-ray emission NICER picks up comes primarily from hotspots at the base of the neutron star’s magnetic poles, where spiraling particles crash into the surface. Right away, it became clear that the magnetic field is complex. The hotspots are on the same hemisphere for both J0030 and J0740, which means that these neutron stars do not have perfect “bar magnet” dipole fields.

    Watts’ and Miller’s teams have now analyzed hotspots on two neutron stars, mapping their locations and shapes as they whirl around. The first one, designated J0030+0451, is a lightweight at 1.4 times the mass of the Sun, with barely the heft to collapse into a neutron star rather than a white dwarf. Results for this object were published in 2019. The second, J0470+6620, is in the heavyweight class with 2.1 solar masses.

    There are some slight differences between the teams’ analyses, but the end result is the same: Neutron stars are generally larger than scientists thought they might be.

    “Our new measurements of J0740 show that even though it’s almost 50% more massive than J0030, it’s essentially the same size,” Watts says. “That challenges some of the more squeezable models of neutron star cores, including versions where the interior is just a sea of quarks.”

    4
    This simplified mass-radius plot shows two extreme possibilities for neutron star cores: Either matter in the cores is “squishy,” disintegrating into quarks, or “stiff,” remaining bound in neutrons, hyperons, or other exotic material. While gravitational-wave data (GW 170817) spans both scenarios, NICER measurements (J0030 and J0740) show that neutron star cores are made of stiffer stuff that stands up to high pressure.
    Sanjay Redding / APS meeting.

    Yet even as quark soup cores are ruled out, the larger size also suggests that the pressure in the core is more intense than previously realized. Whatever is in the core has to stand up to that pressure, and that also appears to rule out simpler neutron cores. Some hybrid scenarios incorporating neutrons and quarks might work.

    There’s another option too: Neutron star cores might contain something more massive than neutrons: a type of particle known as a hyperon. There are several particles classified as hyperons, and each one incorporates strange quarks. (Neutrons and protons have only up and down quarks.) Hyperons thus have some “strange” properties compared to neutrons and protons. Though they’ve been detected in particle accelerators, they’re unstable and decay quickly — but in neutron star cores, they might be stable enough to stick around for awhile.

    “Our fervent hope is that at least we’re able to make a lot of nuclear physicists sweat, because [the NICER result] is not easy to get into their models,” Miller says.

    5
    The NICER measurements of the two neutron stars, the less massive J0030 and the more massive J0740, rule out the “squishiest” scenarios for matter in the core, including pure quark models. However, the measurements also appear to preclude simpler models, labeled “nucleonic,” in which the core consists of just neutrons (with some protons for stability). Possible remaining scenarios include exotic hyperons or a combination of particles (hybrid). Anna Watts / APS meeting.

    Zaven Arzoumanian (NASA Goddard Space Flight Center), the deputy principal investigator and science lead of the NICER mission, says there’s more to come.

    “We have a handful of additional pulsars that NICER is targeting,” he says. “We have collected a significant amount of data already for all of them, and we are analyzing them mostly in turn as we go.” Each additional mass and radius measurement will continue to narrow down the possibilities for what’s really inside neutron star cores.

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 8:23 pm on May 3, 2021 Permalink | Reply
    Tags: "1D model helps clarify implosion performance at NIF", , , , , , Particle Physics   

    From National Ignition Facility at DOE’s Lawrence Livermore National Laboratory (US) : “1D model helps clarify implosion performance at NIF” 

    From National Ignition Facility at DOE’s Lawrence Livermore National Laboratory (US)

    Lawrence Livermore National Laboratory(US)/National Ignition Facility

    4.30.21

    Michael Padilla
    padilla37@llnl.gov
    925-341-8692

    1
    These images depict various laser profiles used in the inertial confinement fusion research and provides the experimental set-up for the VISAR-based shock velocity measurement and representative streaked data.

    In inertial confinement fusion (ICF) experiments at the National Ignition Facility (NIF), a spherical shell of deuterium-tritium fuel is imploded in an attempt to reach the conditions needed for fusion, self-heating and eventual ignition. Since theory and simulations indicate that ignition efficacy in one-dimension (1D) improves with increasing imploded fuel convergence ratio, it is useful to understand the sensitivity of the scale-invariant fuel convergence on all measurable or inferable 1D parameters.

    In a paper featured in Physics of Plasmas , researchers have developed a compression scaling model that is benchmarked to 1D implosion simulations spanning a variety of relevant implosion designs. This model is used to compare compressibility trends across all existing indirect-drive layered implosion data for three ablators.

    “The best level of compression of the various designs of indirect-drive implosions at NIF that have used plastic polymer and beryllium shells follow the expectations of a simple physics model,” said Otto “Nino” Landen from Lawrence Livermore National Laboratory (LLNL) who served as lead author. “This has allowed us to rule out certain previously hypothesized effects such as hot electron preheat.”

    A major exception is the high-density carbon shells that have so far exhibited a remarkably constant lower level of compression, independent of the laser drive conditions, he said.

    “Achieving ignition is fundamentally recognized as a trade-off between more energy coupled to the capsule requiring more efficient hohlraums or a larger laser, and improving the level of capsule compression,” Landen said. “So, understanding what the NIF implosion database has told us so far about compression trends as we varied laser and capsule parameters seemed important as a first step to motivating further research in improving compression without necessarily resorting to a higher laser energy demand.”

    This trending work is part of improving understanding of and optimizing ICF implosion performance on the quest for robust ignition that also could be applied to the direct-drive ICF database.

    The work was conducted by first validating a simple analytic model for the level of capsule compression as a function of various laser and capsule parameters by comparing to 1D simulations.

    Researchers then compared the compression model scaling to all NIF cryogenic implosions shot to date using a combination of existing optical, X-ray and nuclear data, so essentially a physics-grounded empirical approach. This also required developing approximate analytic models for relating the expected compressibility of the implosion to the X-ray driven pressure profile applied to it in the hohlraum as measured by the NIF VISAR system.

    Landen said that since high-density carbon shells are currently giving the best neutron yields despite the reduced compression trends presented in this paper, researchers have increased focus on testing physics-based hypotheses such as hydrodynamic instabilities leading to mixing between the shell and DT, and as yet untested schemes for improving compression in high-density carbon shell implosions.

    The work was conducted by researchers from LLNL, University of Rochester Laboratory for Laser Energetics(LLE) and Los Alamos National Laboratory. Co-authors include: John Lindl, Steve Haan, Daniel Casey, Peter Celliers, David Fittinghoff, Narek Gharibyan, Gary Grim, Ed Hartouni, Omar Hurricane, Brian MacGowan, Stephan MacLaren, Marius Millot, Jose Milovich, Prav Patel, Paul Springer and John Edwards from LLNL; Kevin. Meaney, Harry Robey and Petr Volegov from LANL; and Valeri Goncharov from LLE.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The National Ignition Facility, is a large laser-based inertial confinement fusion (ICF) research device, located at the DOE’s Lawrence Livermore National Laboratory in Livermore, California. NIF uses lasers to heat and compress a small amount of hydrogen fuel with the goal of inducing nuclear fusion reactions. NIF’s mission is to achieve fusion ignition with high energy gain, and to support nuclear weapon maintenance and design by studying the behavior of matter under the conditions found within nuclear weapons. NIF is the largest and most energetic ICF device built to date, and the largest laser in the world.

    Construction on the NIF began in 1997 but management problems and technical delays slowed progress into the early 2000s. Progress after 2000 was smoother, but compared to initial estimates, NIF was completed five years behind schedule and was almost four times more expensive than originally budgeted. Construction was certified complete on 31 March 2009 by the U.S. Department of Energy, and a dedication ceremony took place on 29 May 2009. The first large-scale laser target experiments were performed in June 2009 and the first “integrated ignition experiments” (which tested the laser’s power) were declared completed in October 2010.

    Bringing the system to its full potential was a lengthy process that was carried out from 2009 to 2012. During this period a number of experiments were worked into the process under the National Ignition Campaign, with the goal of reaching ignition just after the laser reached full power, some time in the second half of 2012. The Campaign officially ended in September 2012, at about 1⁄10 the conditions needed for ignition. Experiments since then have pushed this closer to 1⁄3, but considerable theoretical and practical work is required if the system is ever to reach ignition. Since 2012, NIF has been used primarily for materials science and weapons research.

    [caption id="attachment_69836" align="alignnone" width="400"] National Igniton Facility- NIF at LLNL

    The preamplifiers of the National Ignition Facility are the first step in increasing the energy of laser beams as they make their way toward the target chamber

    Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.

    LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration

    NNSA

     
  • richardmitnick 11:13 pm on May 2, 2021 Permalink | Reply
    Tags: "NA64 sets bounds on how much new X bosons could change the electron’s magnetism", , , , , NA64 describes a search for new unknown particles – lightweight “X bosons” that could carry a new force., , Particle Physics, Physicists continue to search for new particles and forces that could help complete the model and also explain some tensions with the model., , The Standard Model of particle physics is alive and well. But it is not complete.   

    From European Organization for Nuclear Research (Organisation européenne pour la recherche nucléaire)(EU) [CERN]: “NA64 sets bounds on how much new X bosons could change the electron’s magnetism” 

    Cern New Bloc

    Cern New Particle Event

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

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

    29 April, 2021

    Ana Lopes

    CERN NA64.

    NA64

    The Standard Model of particle physics is alive and well.

    Standard Model of Particle Physics, Quantum Diaries

    But it is not complete, so physicists continue to search for new particles and forces that could help complete the model and also explain some tensions with the model – or “anomalies” – in the behaviour of known particles. In a paper accepted for publication in Physical Review Letters, NA64 describes how a search for new unknown particles – lightweight “X bosons” that could carry a new force – has allowed it to set bounds on how much these particles could contribute to a fundamental property of the electron, in which an apparent anomaly has recently emerged.

    The property in question is the anomalous magnetic moment. The magnetic moment of a particle is a measure of how the particle interacts with a magnetic field. The anomalous magnetic moment is the part of the magnetic moment caused by the interaction of the particle with “virtual” particles that continually pop into and out of existence. These virtual particles comprise all the known particles, predicted by the Standard Model, but they could also include particles never before observed. Therefore, a difference between the Standard Model prediction of the anomalous magnetic moment of a particle and a high-precision measurement of this property could be a sign of new physics in the form of new particles or forces.

    The most striking example of such an anomaly is the muon’s anomalous magnetic moment, for which DOE’s Fermi National Accelerator Laboratory (US) in the US recently announced [4.7.21] [Physical Review Letters] a difference with theory at a significance level of 4.2 standard deviations – just a little below the 5 standard deviations required to claim a discovery of new physics. But there is another example, although at a lower significance level: the Standard Model’s prediction of the electron’s anomalous magnetic moment, based on the measurement of the fundamental constant of nature that sets the strength of the electromagnetic force, differs from the direct experimental measurement at a level of 1.6 or 2.4 standard deviations, depending on which of two measurements of the fundamental constant is used.

    Like other anomalies, this anomaly may fade away as more measurements are made or as theoretical predictions improve, but it could also be an early indication of new physics, so it is worth investigating. In its new study, the NA64 collaboration set out to investigate whether new lightweight X bosons could contribute to the electron’s anomalous magnetic moment and explain this apparent anomaly.

    NA64 is a fixed-target experiment that directs an electron beam of 100-150 GeV energy, generated using a secondary beamline from the Super Proton Synchrotron, onto a target to look for new particles produced by collisions between the beam’s electrons and the target’s atomic nuclei.

    In the new study, the NA64 team searched for lightweight X bosons by looking for the “missing” collision energy they would carry away. This energy can be identified by analysing the energy budget of the collisions.

    Analysing data collected in 2016, 2017 and 2018, which in total corresponded to about three hundred billion electrons hitting the target, the NA64 researchers were able to set bounds on the strength of the interaction of X bosons with an electron and, as a result, on the contributions of these particles to the electron’s anomalous magnetic moment. They found that X bosons with a mass below 1 GeV could contribute at most between one part in a quadrillion and one part in ten trillions, depending on the X boson’s mass.

    “These contributions are too small to explain the current anomaly in the electron’s anomalous magnetic moment,” says NA64 spokesperson Sergei Gninenko. “But the fact that NA64 reached an experimental sensitivity that is better than the current accuracy of the direct measurements of the electron’s anomalous magnetic moment, and of recent high-precision measurements of the fine-structure constant, is amazing. It shows that NA64 is well placed to search for new physics, and not only in the electron’s anomalous magnetic moment.”

    See the full article here.


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

    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier


    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS

    ALICE

    CMS

    LHCb

    LHC

    OTHER PROJECTS AT CERN

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

     
  • richardmitnick 7:16 pm on May 2, 2021 Permalink | Reply
    Tags: , , , , Large Hadron Collider’s LHCb detector, Many people would say supersymmetry is almost dead., , , Particle Physics, , , Some solutions nevertheless exist that could miraculously fit both. One is the leptoquark—a hypothetical particle that could have the ability to transform a quark into either a muon or an electron ., , , The data that the LHC has produced so far suggest that typical superpartners-if they exist-cannot weigh less than 1000 protons., The LHCb muon anomalies suffer from the same problem as the new muon-magnetism finding: various possible explanations exist but they are all “ad hoc”, There is one other major contender that might reconcile both the LHCb and Muon g – 2 discrepancies. It is a particle called the Z′ boson because of its similarity with the Z boson.   

    From Scientific American: “Muon Results Throw Physicists’ Best Theories into Confusion” 

    From Scientific American

    April 29, 2021
    Davide Castelvecchi

    The Large Hadron Collider’s LHCb detector reported anomalies in the behavior of muons, two weeks before the FNAL Muon g – 2 experiment announced a puzzling finding about muon magnetism.

    Physicists should be ecstatic right now. Taken at face value, the surprisingly strong magnetism of the elementary particles called muons, revealed by an experiment this month [Nature], suggests that the established theory of fundamental particles is incomplete. If the discrepancy pans out, it would be the first time that the theory has failed to account for observations since its inception five decades ago—and there is nothing physicists love more than proving a theory wrong.

    The Muon g − 2 collaboration at the Fermi National Accelerator Laboratory (Fermilab) outside Chicago, Illinois, reported the latest measurements in a webcast on 7 April, and published them in Physical Review Letters. The results are “extremely encouraging” for those hoping to discover other particles, says Susan Gardner, a physicist at the University of Kentucky (US) in Lexington.

    But rather than pointing to a new and revolutionary theory, the result—announced on 7 April by the FNAL Muon g – 2 experiment near Chicago, Illinois—poses a riddle. It seems maddeningly hard to explain it in a way that is compatible with everything else physicists know about elementary particles. And additional anomalies in the muon’s behaviour, reported in March by a collider experiment [LHCb above], only make that task harder. The result is that researchers have to perform the theoretical-physics equivalent of a triple somersault to make an explanation work.

    Zombie models

    Take supersymmetry, or SUSY, a theory that many physicists once thought was the most promising for extending the current paradigm, the standard model of particle physics.

    Supersymmetry comes in many variants, but in general, it posits that every particle in the standard model has a yet-to-be-discovered heavier counterpart, called a superpartner. Superpartners could be among the ‘virtual particles’ that constantly pop in and out of the empty space surrounding the muon, a quantum effect that would help to explain why this particle’s magnetic field is stronger than expected.

    If so, these particles could solve two mysteries at once: muon magnetism and dark matter, the unseen stuff that, through its gravitational pull, seems to keep galaxies from flying apart.

    Until ten years ago, various lines of evidence had suggested that a superpartner weighing as much as a few hundred protons could constitute dark matter. Many expected that the collisions at the Large Hadron Collider (LHC) outside Geneva, Switzerland, would produce a plethora of these new particles, but so far none has materialized.

    “Many people would say supersymmetry is almost dead,” says Dominik Stöckinger, a theoretical physicist at the Dresden University of Technology [Technische Universität Dresden] (DE), who is a member of the Muon g – 2 collaboration. But he still sees it as a plausible way to explain his experiment’s findings. “If you look at it in comparison to any other ideas, it’s not worse than the others,” he says.

    The data that the LHC has produced so far suggest that typical superpartners-if they exist-cannot weigh less than 1,000 protons (the bounds can be higher depending on the type of superparticle and the flavour of supersymmetry theory).

    There is one way in which Muon g – 2 could resurrect supersymmetry and also provide evidence for dark matter, Stöckinger says. There could be not one superpartner, but two appearing in LHC collisions, both of roughly similar masses—say, around 550 and 500 protons. Collisions would create the more massive one, which would then rapidly decay into two particles: the lighter superpartner plus a run-of-the-mill, standard-model particle carrying away the 50 protons’ worth of mass difference.

    The LHC detectors are well-equipped to reveal this kind of decay as long as the ordinary particle—the one that carries away the mass difference between the two superpartners—is large enough. But a very light particle could escape unobserved. “This is well-known to be a blind spot for LHC,” says Michael Peskin, a theoretician at the DOE’s SLAC National Accelerator Laboratory (US) in Menlo Park, California at Stanford University (US).

    The trouble is that models that include two superpartners with similar masses also tend to predict that the Universe should contain a much larger amount of dark matter than astronomers observe. So an additional mechanism would be needed—one that can reduce the amount of predicted dark matter, Peskin explains. This adds complexity to the theory. For it to fit the observations, all its parts would have to work “just so”.

    Meanwhile, physicists have uncovered more hints that muons behave oddly. An experiment at the LHC, called LHCb, has found tentative evidence that muons occur significantly less often than electrons as the breakdown products of certain heavier particles called B mesons. According to the standard model, muons are supposed to be identical to electrons in every way except for their mass, which is 207 times larger. As a consequence, B mesons should produce electrons and muons at rates that are nearly equal.

    The LHCb muon anomalies suffer from the same problem as the new muon-magnetism finding: various possible explanations exist but they are all “ad hoc”, says physicist Adam Falkowski, at the Paris-Saclay University [Université Paris-Saclay] (FR). “I’m quite appalled by this procession of zombie SUSY models dragged out of their graves,” says Falkowski.

    The task of explaining Muon g – 2’s results becomes even harder when researchers try concoct a theory that fits both those findings and the LHCb results, physicists say. “Extremely few models could explain both simultaneously,” says Stöckinger. In particular, the supersymmetry model that explains Muon g – 2 and dark matter would do nothing for LHCb.

    Some solutions nevertheless exist that could miraculously fit both. One is the leptoquark—a hypothetical particle that could have the ability to transform a quark into either a muon or an electron (which are both examples of a lepton). Leptoquarks could resurrect an attempt made by physicists in the 1970s to achieve a ‘grand unification’ of particle physics, showing that its three fundamental forces—strong, weak and electromagnetic—are all aspects of the same force.

    Most of the grand-unification schemes of that era failed experimental tests, and the surviving leptoquark models have become more complicated—but they still have their fans. “Leptoquarks could solve another big mystery: why different families of particles have such different masses,” says Gino Isidori, a theoretician at the University of Zürich [Universität Zürich ] (CH) in Switzerland. One family is made of the lighter quarks—the constituents of protons and neutrons—and the electron. Another has heavier quarks and the muon, and a third family has even heavier counterparts.

    Apart from the leptoquark, there is one other major contender that might reconcile both the LHCb and Muon g – 2 discrepancies. It is a particle called the Z′ boson because of its similarity with the Z boson, which carries the ‘weak force’ responsible for nuclear decay. It, too, could help to solve the mystery of the three families, says Ben Allanach, a theorist at the University of Cambridge (UK). “We’re building models where some features come out very naturally, you can understand these hierarchies,” he says. He adds that both leptoquarks and the Z′ boson have an advantage: they still have not been completely ruled out by the LHC, but the machine should ultimately see them if they exist.

    The LHC is currently undergoing an upgrade, and it will start to smash protons together again in April 2022. The coming deluge of data could strengthen the muon anomalies and perhaps provide hints of the long-sought new particles (although a proposed electron–positron collider, primarily designed to study the Higgs boson, might be needed to address some of the LHC’s blind spots, Peskin says). Meanwhile, beginning next year, Muon g – 2 will release further measurements. Once it’s known more precisely, the size of the discrepancy between muon magnetism and theory could itself rule out some explanations and point to others.

    Unless, that is, the discrepancies disappear and the standard model wins again. A new calculation, reported this month, of the standard model’s prediction for muon magnetism gave a value much closer to the experimental result. So far, those who have bet against the standard model have always lost, which makes physicists cautious. “We are—maybe—at the beginning of a new era,” Stöckinger says.

    See the full article here .


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    Scientific American, the oldest continuously published magazine in the U.S., has been bringing its readers unique insights about developments in science and technology for more than 160 years.

     
  • richardmitnick 2:11 pm on April 30, 2021 Permalink | Reply
    Tags: "CERN 'Awake' brings proton bunches into sync", , MPG Institute for Physics [Max-Planck-Institut für Physik] (DE), , Particle Physics, , The future of particle acceleration has begun., The proton source of "Awake" is the SPS ring at Cern- a pre-accelerator for the 27-kilometer circumference ring of the Large Hadron Collider (LHC).   

    From MPG Institute for Physics [Max-Planck-Institut für Physik] (DE) : “CERN ‘Awake’ brings proton bunches into sync” 

    From MPG Institute for Physics [Max-Planck-Institut für Physik] (DE)

    April 23, 2021

    Dr. Patric Muggli
    Max Planck Institute for Physics, München
    +49 89 32354-580
    muggli@mpp.mpg.de

    Fabian Batsch
    Max Planck Institute for Physics, München
    +49 89 32354-561
    fbatsch@mpp.mpg.de

    The future of particle acceleration has begun. Awake is a promising concept for a completely new method with which particles can be accelerated even over short distances. The basis for this is a plasma wave that accelerates electrons and thus brings them to high energies. A team led by the Max Planck Institute for Physics now reports a breakthrough in this context. For the first time, they were able to precisely time the production of the proton microbunches that drive the wave in the plasma. This fulfills an important prerequisite for using the Awake technology for collision experiments.

    1
    Proton bunches in sync: A train of short proton bunches travels through the plasma field, forming a wave on which electrons can be accelerated. CERN AWAKE

    How do you create a wave for electrons? The carrier substance for this is a plasma (i.e., an ionized gas in which positive and negative charges are separated). Directing a proton beam through the plasma creates a wave on which electrons ride and are accelerated to high energies.

    The proton source of Awake is the SPS ring at Cern- a pre-accelerator for the 27-kilometer circumference ring of the Large Hadron Collider (LHC). It produces proton bunches about 10-cm long. “However, in order to generate a large amplitude plasma wave, the proton bunch length must be much shorter – in the millimeter range,” explains Fabian Batsch, PhD student at the Max Planck Institute for Physics.

    The scientists take advantage of self-modulation, a “natural” interaction between the bunch and plasma. “In the process, the longer proton bunch is split into high-energy proton microbunches of only a few millimeters in length, building the train beam,” says Batsch. “This process forms a plasma wave, which propagates with the train travelling through the plasma field.”

    Precise timing allows ideal electron acceleration

    However, a stable and reproducible field is required to accelerate electrons and bring them to collision. This is exactly what the team has found a solution for now. “If a sufficiently large electric field is applied when the long proton bunch is injected and the self-modulation is thus immediately set in motion.”

    “Since the plasma is formed right away, we can exactly time the phase of the short proton microbunches,” says Patric Muggli, head of the Awake working group at the Max Planck Insstitute for Physics. “This allows us to set the pace for the train. Thus, the electrons are caught and accelerated by the wave at the ideal moment.”

    First research projects in sight

    The “Awake” technology is still in the early stages of development. However, with each step toward success, the chances of this accelerator technology actually being used in the coming decades increase. The first proposals for smaller accelerator projects (e.g., for example to study the fine structure of protons) are to be made as early as 2024.

    According to Muggli, the advantages of the novel accelerator technology – plasma wakefield acceleration – are obvious: “With this technology, we can reduce the distance needed to accelerate electrons to peak energy by a factor of 20. The accelerators of the future could therefore be much smaller. This means: Less space, less effort, and therefore lower costs.”

    Science paper:
    Physical Review Letters

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The MPG Institute for Physics [Max-Planck-Institut für Physik](DE) (MPP) is a physics institute in Munich, Germany that specializes in high energy physics and astroparticle physics. It is part of the Max-Planck-Gesellschaft and is also known as the Werner Heisenberg Institute, after its first director in its current location.

    The founding of the institute traces back to 1914, as an idea from Fritz Haber, Walther Nernst, Max Planck, Emil Warburg, Heinrich Rubens. On October 1, 1917, the institute was officially founded in Berlin as Kaiser-Wilhelm-Institut für Physik (KWIP, Kaiser Wilhelm Institute for Physics) with Albert Einstein as the first head director. In October 1922, Max von Laue succeeded Einstein as managing director. Einstein gave up his position as a director of the institute in April 1933. The Institute took part in the German nuclear weapon project from 1939-1942.

    In June 1942, Werner Heisenberg took over as managing director. A year after the end of fighting in Europe in World War II, the institute was moved to Göttingen and renamed the MPG for Physics, with Heisenberg continuing as managing director. In 1946, Carl Friedrich von Weizsäcker and Karl Wirtz joined the faculty as the directors for theoretical and experimental physics, respectively.

    In 1955 the institute made the decision to move to Munich, and soon after began construction of its current building, designed by Sep Ruf. The institute moved into its current location on September 1, 1958 and took on the new name the Max Planck Institute for Physics and Astrophysics, still with Heisenberg as the managing director. In 1991, the institute was split into the Max Planck Institute for Physics, the MPG Institute for Astrophysics [Max-Planck-Institut für Astrophysik] (DE) and the MPG Institute for extraterrestrial Physics [MPG Institut für extraterrestrische Physik] (DE).

     
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