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  • richardmitnick 1:52 pm on April 20, 2018 Permalink | Reply
    Tags: , , , , , Particle Physics,   

    From FNAL: “Turning up the luminosity: Fermilab contributes important CMS upgrades” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    April 19, 2018
    Sarah Lawhun

    Fermilab is developing and testing a revolutionary particle detector concept, one that will enable the CMS detector at CERN’s Large Hadron Collider to handle 10 times the number of particle collisions currently being produced at the European machine — a virtual avalanche. This upgrade will make the LHC the world’s highest-energy proton smasher in the next decades.

    CERN CMS

    CERN CMS Higgs Event

    CERN CMS pre-Higgs Event

    At the LHC, two beams of protons are accelerated to nearly the speed of light around the collider’s 18-mile ring in opposite directions, colliding inside one of four detectors, including one called CMS. The protons smash together in the detector’s core, producing a plethora of subatomic particles that fly off in all directions.

    The detector — a gigantic, barrel-shaped device that could surround a whale if the instrument were hollow — is packed with layers of detectors that surround the collision site. Think of it as a superhigh-tech onion — a 14,000-ton onion equipped with billions of sensors in its core, buried 100 meters underground. These layers collect data from the particles emerging from the collisions, tracking their paths as they shoot away from the center.

    Higher luminosity for the Higgs

    In the late 2020s, CERN will turn up the LHC’s beam luminosity, or the number of protons packed into its beams, resulting in showers of even more particles.

    This increased abundance will give scientists more opportunities to reveal new particles and processes, helping us refine our understanding of how the universe works.

    The CMS and ATLAS co-discovered the Higgs boson in 2012, a discovery that led to a Nobel Prize. Now, both experiments are working to learn more about the Higgs and how it behaves — and in the process to maybe reveal something unexpected.

    CERN/ATLAS detector

    “There’s the possibility of not only making very precise measurements of phenomena that will allow us to test our assumptions about the Standard Model, but also gaining an increased scope for new physics that might be just beyond where we’re reaching now,” said Ron Lipton, a Fermilab scientist on the CMS experiment who is coordinating the detector project at national level.

    Of course, the LHC’s high luminosity won’t do much good if the detector isn’t equipped to handle it.

    4
    CMS tracker for HL-LHC

    CERN CMS Tracker for HL-LHC

    See the full article here .

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    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.


    FNAL/MINERvA

    FNAL DAMIC

    FNAL Muon g-2 studio

    FNAL Short-Baseline Near Detector under construction

    FNAL Mu2e solenoid

    Dark Energy Camera [DECam], built at FNAL

    FNAL DUNE Argon tank at SURF

    FNAL/MicrobooNE

    FNAL Don Lincoln

    FNAL/MINOS

    FNAL Cryomodule Testing Facility

    FNAL Minos Far Detector

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA

    FNAL/NOvA experiment map

    FNAL NOvA Near Detector

    FNAL ICARUS

    FNAL Holometer

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  • richardmitnick 1:24 pm on April 20, 2018 Permalink | Reply
    Tags: , , , , , , , Particle Physics,   

    From FNAL: “CMS experiment at the LHC sees first 2018 collisions” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    April 19, 2018
    Cecilia Gerber
    Sergo Jindariani

    Cecilia Gerber and Sergo Jindariani are co-coordinators of the LHC Physics Center at Fermilab.

    After months of winter shutdown, the CMS experiment at the Large Hadron Collider (LHC) is once again seeing collisions and is ready to take data.

    CERN CMS

    CERN CMS Higgs Event

    CERN CMS pre-Higgs Event

    The shutdown months have been very busy for CMS physicists, who used this downtime to improve the performance of the detector by completing upgrades and repairs of detector components. The LHC will continue running until December 2018 and is expected to deliver an additional 50 inverse femtobarns of integrated luminosity to the ATLAS and CMS experiments. This year of data-taking will conclude Run-2, after which the collider and its experiment will go into a two-year long shutdown for further upgrades.

    Run-2 of the LHC has been highly successful, with close to 100 inverse femtobarns of integrated luminosity already delivered to the experiments in 2016 and 2017. These data sets enabled CMS physicists to perform many measurements of Standard Model parameters and searches for new physics. New data will allow CMS to further advance into previously uncharted territory. Physicists from the LHC Physics Center at Fermilab have been deeply involved in the work during the winter shutdown. They are now playing key roles in processing and certification of data recorded by the CMS detector, while looking forward to analyzing the new data sets for a chance to discover new physics.


    This is an event display of one of the early 2018 collisions that took place at the CMS experiment at CERN.

    See the full article here .

    Please help promote STEM in your local schools.

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    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.


    FNAL/MINERvA

    FNAL DAMIC

    FNAL Muon g-2 studio

    FNAL Short-Baseline Near Detector under construction

    FNAL Mu2e solenoid

    Dark Energy Camera [DECam], built at FNAL

    FNAL DUNE Argon tank at SURF

    FNAL/MicrobooNE

    FNAL Don Lincoln

    FNAL/MINOS

    FNAL Cryomodule Testing Facility

    FNAL Minos Far Detector

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA

    FNAL/NOvA experiment map

    FNAL NOvA Near Detector

    FNAL ICARUS

    FNAL Holometer

     
  • richardmitnick 1:01 pm on April 20, 2018 Permalink | Reply
    Tags: , , , , , Particle Physics,   

    From CERN: “CERN’s SPS experiments restart” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    CERN

    20 Apr 2018
    Ana Lopes

    The Super Proton Synchrotron (SPS), CERN’s second-largest accelerator. (Image: Julien Ordan/CERN)

    At CERN, springtime usually marks the restart of the Laboratory’s experiments. But, while most eyes turn towards the restart of the Large Hadron Collider (LHC) and its experiments, the research programme at the Super Proton Synchrotron (SPS), CERN’s second-largest accelerator, has also resumed.

    This month witnesses the restart of data taking for a range of experiments fed with particle beams from the SPS. These experiments are an essential arm of CERN’s experimental programme, addressing areas as varied as precision tests of the Standard Model and studies of the quark–gluon state of matter, believed to have existed shortly after the Big Bang.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.


    Standard Model of Particle Physics from Symmetry Magazine

    On 9 April, data taking restarted at three SPS experiments: NA58/COMPASS, NA62 and NA63. NA58 directs several types of particle onto a variety of fixed targets to look at the ways in which elementary particles called quarks and gluons combine to make up protons, neutrons and other hadrons. This year, the experiment is shooting quark­–antiquark pairs called pions at a proton target to collect the world’s largest data set on a hadron–hadron collision process called the Drell–Yan mechanism, in order to make a fundamental test of the theory of the strong interaction between quarks and gluons.

    NA62, another fixed-target experiment, aims to precisely test the Standard Model by looking for the super-rare decay of a positively charged particle known as a kaon into a positively charged pion and a neutrino–antineutrino pair. Earlier this year, the NA62 team reported the first candidate event for this decay, and the team aims to run the experiment for a record number of 218 days this year. If the Standard Model prediction for the number of events is correct, NA62 should see about 20 events with the data collected before the end of this year.

    NA63 fires beams of electrons or antielectrons at a variety of fixed targets, among them large diamonds, to study radiation processes in strong electromagnetic fields, like those seen in astrophysical objects such as highly magnetised neutron stars. On the cards for this year is a measurement of the so-called radiation reaction – the effect of the electromagnetic field emitted by an accelerated charged particle on the particle’s motion. Details of this effect are under debate, even though the effect has been known about for over a hundred years.

    The NA61/SHINE SPS experiment is set to restart data taking on 25 April. NA61 studies the production of hadrons using collisions between several types of hadron or nucleus and an assortment of nuclear targets. In store for this year are, among others, measurements of heavy hadrons with charm-type quarks produced in collisions between lead nuclei, and measurements of fragmentation of light nuclei. The first of these measurements are relevant for studying the quark–gluon state of matter, and the second are needed to understand the propagation of cosmic rays in the Milky Way.

    3
    Inside NA61, one of several experiments fed with particle beams from the SPS. (Image: Julien Ordan/CERN)

    These are not the only experiments benefiting from particle beams from the SPS. NA64 and AWAKE are both set to start taking data in the coming months. With such a rich diversity of experiments linked to the SPS, the accelerator is so much more than just a link in the accelerator chain taking protons to the LHC.

    See the full article here.

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New

    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    LHC

    CERN LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles

    OTHER PROJECTS AT CERN

    CERN AEGIS

    CERN ALPHA

    CERN ALPHA

    CERN AMS

    CERN ACACUSA

    CERN ASACUSA

    CERN ATRAP

    CERN ATRAP

    CERN AWAKE

    CERN AWAKE

    CERN CAST

    CERN CAST Axion Solar Telescope

    CERN CLOUD

    CERN CLOUD

    CERN COMPASS

    CERN COMPASS

    CERN DIRAC

    CERN DIRAC

    CERN ISOLDE

    CERN ISOLDE

    CERN LHCf

    CERN LHCf

    CERN NA62

    CERN NA62

    CERN NTOF

    CERN TOTEM

    CERN UA9

     
  • richardmitnick 4:17 pm on April 16, 2018 Permalink | Reply
    Tags: , , , , LARP-US LHC Accelerator Research Program, , Particle Physics,   

    From CERN: “LHC luminosity upgrade project moving to next phase” [2015. Really? So what is new here?] 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    CERN

    29 Oct 2015 [Really?]

    1
    29 October 2015. This week more than 230 scientists and engineers from around the world met at CERN1 to discuss the High-Luminosity LHC – a major upgrade to the Large Hadron Collider (LHC) that will increase the accelerator’s discovery potential from 2025.

    After a four year long design study the project is now moving into its second phase, which will see the development of industrial prototypes for various parts of the accelerator.

    Luminosity is a crucial indicator of performance for an accelerator. It is proportional to the number of particles colliding within a defined amount of time. Since discoveries in particle physics rely on statistics, the greater the number of collisions, the more chances physicists have to see a particle or process that they have not seen before.

    The High-Luminosity LHC will increase the luminosity by a factor of 10, delivering 10 times more collisions than the LHC would do over the same period of time.

    It will therefore provide more accurate measurements of fundamental particles and enable physicists to observe rare processes that occur below the current sensitivity level of the LHC. With this upgrade, the LHC will continue to push the limits of human knowledge, enabling physicists to explore beyond the Standard Model and Brout-Englert-Higgs mechanism.

    “The LHC already delivers proton collisions at the highest energy ever,” said CERN Director General Rolf Heuer. “The High-Luminosity LHC will produce collisions 10 times more rapidly, increasing our discovery potential and transforming the LHC into a machine for precision studies: the natural next step for the high energy frontier.”

    The increase in luminosity will mean physicists will be able to study new phenomena discovered by the LHC, such as the Higgs boson, in more detail. The High-Luminosity LHC will produce 15 million Higgs bosons per year compared to the 1.2 million in total created at the LHC between 2011 and 2012.

    Upgrading the LHC will be a challenging procedure and relies on several breakthrough technologies currently under development.

    “We have to innovate in many fields, developing cutting-edge technologies for magnets, the optics of the accelerator, superconducting radiofrequency cavities, and superconducting links,” explained Lucio Rossi, Head of the High-Luminosity LHC project.

    Some 1.2 km of the LHC will be replaced by these new technologies, which include cutting-edge 12 Tesla superconducting quadrupole magnets built using a superconducting compound of niobium and tin [built by whom?*]. These will strongly focus the beam to increase the probability of collisions occurring and will be installed at each side of the ATLAS and CMS experiments.

    There are also brand new superconducting radiofrequency cavities, called “crab cavities” [built by whom?*], which will be used to orientate the beam before the collision to increase the length of the area where the beams overlap. New electrical transfer lines, based on high temperature superconductors, will be able to carry currents of record intensities to the accelerator, up to 100,000 amps, over 100 metres.

    “The High-Luminosity LHC will use pioneering technologies – such as high field niobium-tin magnets [built by whom?] – for the first time,” said Frédérick Bordry, CERN Director for Accelerators and Technology. “This will not only increase the discovery potential of the LHC but also serve as a proof of concept for future accelerators.”

    All these technologies have been explored since 2011 in the framework of the HiLumi LHC Design Study – partly financed by the European Commission’s FP7 programme. HiLumi LHC brought together a large number of laboratories from CERN’s member states, as well as from Russia, Japan and the US. American institutes participated in the project with the support of the US LHC Accelerator Research Program (LARP), funded by the U.S. Department of Energy. Some 200 scientists from 20 countries collaborated on this first successful phase.

    The meeting this week marks the end of this hugely complex and collaborative design phase of the High-Luminosity LHC project. The project will now focus on the prototyping and industrialization of the technologies before the construction phase can begin.

    *Outside builders, such as BNL,FNAL,LBNL, SLAC, DESY, KEK, etc. deserve to be credited.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New

    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    LHC

    CERN LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles

    OTHER PROJECTS AT CERN

    CERN AEGIS

    CERN ALPHA

    CERN ALPHA

    CERN AMS

    CERN ACACUSA

    CERN ASACUSA

    CERN ATRAP

    CERN ATRAP

    CERN AWAKE

    CERN AWAKE

    CERN CAST

    CERN CAST Axion Solar Telescope

    CERN CLOUD

    CERN CLOUD

    CERN COMPASS

    CERN COMPASS

    CERN DIRAC

    CERN DIRAC

    CERN ISOLDE

    CERN ISOLDE

    CERN LHCf

    CERN LHCf

    CERN NA62

    CERN NA62

    CERN NTOF

    CERN TOTEM

    CERN UA9

     
  • richardmitnick 10:12 am on April 16, 2018 Permalink | Reply
    Tags: , , , , , Particle Physics, , Ready- Set- Go   

    From CERN ALICE: “Ready, Set, Go” 

    CERN
    CERN New Masthead

    16 April 2018
    Virginia Greco

    During the recent weeks, test, calibration and configuration activities were carried on to prepare the ALICE detector for the imminent restart of beam. In advance with respect to the original plan, the LHC is expected to deliver collisions with stable beams on 17 April.

    1
    The LHC is getting ready for injecting physics beam. The first collisions with stable beams of 2018 will be delivered between 16 and 17 of April.

    Thanks to the excellent performance exhibited by the LHC during the latest weeks, the schedule of the accelerator restarting has been compressed and collisions with stable beams will be delivered beforehand. As a consequence, the ALICE experiment has sped up its commissioning as well to be ready to take data as soon as possible.

    The operations in the experimental cavern, which included some minor repairing and interventions on the muon arm and the TPC, are concluded. Technical runs were started at the beginning of March. During them, the various detectors and systems were left working for many hours in a row – without beams in the accelerator – to check their correct functioning and their stability over time. In the first two weeks, these tests were performed only between 7 am and 11 pm and then the detector switched off, so that no crew was required to stay in the control room at night. Following this, full shifts (24 hours a day) were started and tests continued. Dry runs like these are key to the preparation for data taking, since they allow the experts to identify possible issues and glitches and to fix them in time for the restart.

    The detectors were gradually included in these common coordinated runs but only after successfully completing a reintegration procedure of their detector control system (DCS), necessary to ensure proper transitioning of detectors from normal to beam-safe running conditions.

    CERN/ALICE Detector

    ALICE Run Control Center

    The TPC and the TRD also went through an energy calibration (called “krypton calibration”) performed using a solid rubidium source, which decays into a gaseous excited state of krypton that mixes with the gas volumes of the detectors. This excited state returns to its ground state inside the detector with a known energy spectrum.

    The Data Acquisition System (DAQ) together with the Central Trigger Processor (CTP) and the High-Level Trigger (HLT), in turn, worked to get prepared for the Pb-Pb collisions that will be delivered at the end of the year, from November on. In particular, various tests have been carried out – and will be continued throughout the year whenever possible – to check, tune and improve how the full chain (from the detector signals to the final data storage) behaves when pushed to the limit of its capacity. Specifically, ‘fake’ events, carrying no meaningful information but having rates and sizes similar to those of the events expected in the future Pb-Pb collisions, were generated to put a significant load on the data channels and – partially – on the processing stages.

    After completion of two weeks of dry runs, the ALICE magnet was switched on and data from cosmic ray interactions were taken with many of the detectors until the accelerator team was ready to start test injection in the beam pipe.

    During this beam operation time, when the experts of the machine put in place their commissioning procedure, the ALICE detector has been put in a beam-safe state. In practice, only the systems that have minimal risk of being damaged when hit by the beam when switched on can actually run. The others have to stay in standby mode or run in a non-standard configuration (for example, no high voltage is applied to the detectors that normally require it).

    Collisions with unstable beams were delivered on April 12 and stable beams will be declared at some point between 16 and 17 of April. The ALICE experiment is all set and ready to start its 2018 race.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Meet CERN in a variety of places:


    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS
    ATLAS
    CERN/ATLAS detector

    ALICE
    CERN ALICE New

    CMS
    CERN/CMS Detector

    LHCb

    CERN/LHCb

    LHC

    CERN/LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles


    Quantum Diaries

     
  • richardmitnick 9:43 am on April 16, 2018 Permalink | Reply
    Tags: , , , Particle Physics, , U.S. and India sign agreement providing for neutrino physics collaboration at Fermilab and in India   

    From FNAL: “U.S., India sign agreement providing for neutrino physics collaboration at Fermilab and in India” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    April 16, 2018

    1
    U.S. Secretary of Energy Rick Perry, left, and Indian Atomic Energy Secretary Sekhar Basu, right, signed an agreement on Monday in New Delhi, opening the door for continued cooperation on neutrino research in both countries. In attendance were Hema Ramamoorthi, chief of staff of the U.S. DOE’s Fermi National Accelerator Laboratory, and U.S. Ambassador to India Kenneth Juster. Photo: Fermilab.

    Earlier today, April 16, 2018, U.S. Secretary of Energy Rick Perry and India’s Atomic Energy Secretary Dr. Sekhar Basu signed an agreement in New Delhi to expand the two countries’ collaboration on world-leading science and technology projects. It opens the way for jointly advancing cutting-edge neutrino science projects under way in both countries: the Long-Baseline Neutrino Facility (LBNF) with the international Deep Underground Neutrino Experiment (DUNE) hosted at the U.S. Department of Energy’s Fermilab and the India-based Neutrino Observatory (INO).

    LBNF/DUNE brings together scientists from around the world to discover the role that tiny particles known as neutrinos play in the universe. More than 1,000 scientists from over 170 institutions in 31 countries work on LBNF/DUNE and celebrated its groundbreaking in July 2017. The project will use Fermilab’s powerful particle accelerators to send the world’s most intense beam of high-energy neutrinos to massive neutrino detectors that will explore their interactions with matter.

    INO scientists will observe neutrinos that are produced in Earth’s atmosphere to answer questions about the properties of these elusive particles. Scientists from more than 20 institutions are working on INO.

    “The LBNF/DUNE project hosted by the Department of Energy’s Fermilab is an important priority for the DOE and America’s leadership in science, in collaboration with our international partners,” said Secretary of Energy Rick Perry. “We are pleased to expand our partnership with India in neutrino science and look forward to making discoveries in this promising area of research.”

    Scientists from the United States and India have a long history of scientific collaboration, including the discovery of the top quark at Fermilab.

    “India has a rich tradition of discoveries in basic science,” said Atomic Energy Secretary Basu. “We are pleased to expand our accelerator science collaboration with the U.S. to include the science for neutrinos. Science knows no borders, and we value our Indian scientists working hand-in-hand with our American colleagues. The pursuit of knowledge is a true human endeavor.”

    This DOE-DAE agreement builds on the two countries’ existing collaboration on particle accelerator technologies. In 2013, DOE and DAE signed an agreement authorizing the joint development and construction of particle accelerator components in preparation for projects at Fermilab and in India. This collaborative work includes the training of Indian scientists in the United States and India’s development and prototyping of components for upgrades to Fermilab’s particle accelerator complex for LBNF/DUNE. The upgrades, known as the Proton Improvement Plan-II (PIP-II), include the construction of a 600-foot-long superconducting linear accelerator at Fermilab. It will be the first ever particle accelerator built in the United States with significant contributions from international partners, including also the UK and Italy. Scientists from four institutions in India – BARC in Mumbai, IUAC in New Delhi, RRCAT in Indore and VECC in Kolkata – are contributing to the design and construction of magnets and superconducting particle accelerator components for PIP-II at Fermilab and the next generation of particle accelerators in India.

    Under the new agreement signed today, U.S. and Indian institutions will expand this productive collaboration to include neutrino research projects. The LBNF/DUNE project will use the upgraded Fermilab particle accelerator complex to send the world’s most powerful neutrino beam 800 miles (1,300 kilometers) through the earth to a massive neutrino detector located at Sanford Underground Research Facility in South Dakota. This detector will use almost 70,000 tons of liquid argon to detect neutrinos and will be located about a mile (1.5 kilometers) underground; an additional detector will measure the neutrino beam at Fermilab as it leaves the accelerator complex. Prototype neutrino detectors already are under construction at the European research center CERN, another partner in LBNF/DUNE.

    “Fermilab’s international collaboration with India and other countries for LBNF/DUNE and PIP-II is a win-win situation for everybody involved,” said Fermilab Director Nigel Lockyer. “Our partners get to work with and learn from some of the best particle accelerator and particle detector experts in the world at Fermilab, and we benefit from their contributions to some of the most complex scientific machines in the world, including LBNF/DUNE and the PIP-II accelerator.”

    INO will use a different technology — known as an iron calorimeter — to record information about neutrinos and antineutrinos generated by cosmic rays hitting Earth’s atmosphere. Its detector will feature what could be the world’s biggest magnet, allowing INO to be the first experiment able to distinguish signals produced by atmospheric neutrinos and antineutrinos. The DOE-DAE agreement enables U.S. and Indian scientists to collaborate on the development and construction of these different types of neutrino detectors. More than a dozen Indian institutions are involved in the collaboration on neutrino research.

    Additional quotes:

    Prof. Vivek Datar, INO spokesperson and project director, Taha Institute of Fundamental Research:

    “This will facilitate U.S. participation in building some of the hardware for INO, while Indian scientists do the same for the DUNE experiment. It will also help in building expertise in India in cutting-edge detector technology, such as in liquid-argon detectors, where Fermilab will be at the forefront. At the same time we will also pursue some new ideas.”

    Prof. Naba Mondal, former INO spokesperson, Saha Institute of Nuclear Physics:

    “This agreement is a positive step towards making INO a global center for fundamental research. Students working at INO will get opportunities to interact with international experts.”

    Prof. Ed Blucher, DUNE co-spokesperson, University of Chicago, United States:

    “The international DUNE experiment could fundamentally change our understanding of the universe. Contributions from India and other partner countries will enable us to build the world’s most technologically advanced neutrino detectors as we aim to make groundbreaking discoveries regarding the origin of matter, the unification of forces, and the formation of neutron stars and black holes.”

    Prof. Stefan Soldner-Rembold, DUNE co-spokesperson, University of Manchester, UK:

    “DUNE will be the world’s most ambitious neutrino experiment, driven by the commitment and expertise of scientists in more than 30 countries. We are looking forward to the contributions that our colleagues in India will make to this extraordinary project.”

    To learn more about LBNF/DUNE, visit http://www.fnal.gov/dunemedia. More information about PIP-II is available at http://pip2.fnal.gov.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    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.


    FNAL/MINERvA

    FNAL DAMIC

    FNAL Muon g-2 studio

    FNAL Short-Baseline Near Detector under construction

    FNAL Mu2e solenoid

    Dark Energy Camera [DECam], built at FNAL

    FNAL DUNE Argon tank at SURF

    FNAL/MicrobooNE

    FNAL Don Lincoln

    FNAL/MINOS

    FNAL Cryomodule Testing Facility

    FNAL Minos Far Detector

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA

    FNAL/NOvA experiment map

    FNAL NOvA Near Detector

    FNAL ICARUS

    FNAL Holometer

     
  • richardmitnick 8:58 am on April 13, 2018 Permalink | Reply
    Tags: , , First LHC test collisions of 2018, , , Particle Physics,   

    From CERN: “First LHC collisions of 2018” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    CERN

    12 Apr 2018
    Ana Lopes

    1
    A test collision recorded by the CMS experiment on 12 April 2018. The CMS collaboration uses these first collisions to prepare for data taking, fine-tuning and powering on various subsystems as needed. (Image: CERN)

    Proton slamming has resumed at the Large Hadron Collider (LHC). Almost a fortnight after the collider began circulating proton beams for the first time in 2018, the machine’s operations team has today steered beams into collision. While these are only test collisions, they are an essential step along the way to serious data taking, which is expected to kick off in early May.

    Achieving first test collisions is anything but an easy job. It involves round-the-clock checking and rechecking of the thousands of systems that comprise the LHC. It includes ramping up the energy of each beam to the operating value of 6.5 TeV, checking the beams’ instrumentation and optics, testing electronic feedback systems, aligning jaw-like devices called collimators that close around the beams to absorb stray particles and, finally, focusing the beams to make them collide.

    Each beam consists of packets of protons called bunches. For these test collisions, each beam contains only two “nominal” bunches, each made up of 120 billion protons. This is far fewer than the 1200 bunches per beam that will mark the start of serious data taking and particle hunting. As the year progresses, the operations team will continue to increase the number of bunches in each beam, up to the maximum of 2556.

    With today’s test collisions, the teams of the experiments located at four collision points around the LHC ring (ALICE, LHCb, CMS and ATLAS) will now be able to check and calibrate their detectors. Stay tuned for the next steps.

    Beams are back in the LHC
    29 Mar 2018
    Corinne Pralavorio

    3
    View of the LHC in 2018, before the restart of the accelerato. (Image: Maximilien Brice, Julien Ordan/CERN)

    The Large Hadron Collider is back in business! On Friday 30 March, at 12:17 pm, protons circulated in the 27-km ring for the first time in 2018. The world’s most powerful particle accelerator thus entered its seventh year of data taking and its fourth year at 13 TeV collision energy.

    Restarting an accelerator involves much more than just flicking a switch, especially as the LHC is the final link in an accelerator chain comprising five separate machines. Following the winter break, which enabled teams to carry out a whole host of maintenance operations, the machine operators gradually have brought the infrastructures and accelerators back on line. At the beginning of March, the first protons were extracted from their hydrogen bottle and injected into the Linac2, and then into the PS Booster. On 8 March, it was the turn of the Proton Synchrotron (PS) to receive beams, and then, a week later, the Super Proton Synchrotron (SPS).

    4
    Applause in the CERN Control Centre after the beam makes a first turn of the LHC loop. Sitting, the operators in charge of restarting the accelerator. Standing behind them, from left to right, Rende Steerenberg, Head of Operation, Frédérick Bordry, Director for Accelerators and Technology, Fabiola Gianotti, CERN Director-General, Rossano Giachino, from the LHC operation team, and Jörg Wenninger, in charge of the LHC operation team. (Image: CERN)

    In parallel, the teams have been checking all the LHC hardware, such as the cryogenic cooling systems, the radiofrequency cavities (which accelerate the particles), the power supplies, the magnets, the vacuum system and the safety installations. For example, no fewer than 1 560 electrical circuits had to be powered and about 10 000 tests performed. Only once all these tests had been completed could particles be injected into the LHC.

    Even so, commissioning is far from over. The first beams circulating only have one bunch of particles, which contains 20 times fewer protons than in normal operation. And their energy is limited to the injection energy of 450 GeV. Further adjustments and tests will be needed over the coming days before the energy and the number of bunches in each beam can be increased and the bunches squeezed to produce first collisions. Physics operation should start in May.

    The operation objective for 2018 is to accumulate more data than in 2017: the target is 60 inverse femtobarns (fb-1) of integrated luminosity (against 50 fb-1 in 2017). Luminosity is a measurement of the number of potential collisions per surface unit in a given period of time.

    5
    “LHC page 1” shows the status of the LHC on 30 March. The blue line on the right of the screen indicates the first beam circulating in the LHC in 2018. (Image: CERN)

    While we await collisions in the LHC, data taking is already starting elsewhere. CERN’s accelerators provide particles for a diverse array of experiments. The PS has already started supplying beams to the nuclear physics facility n_TOF and to the experiments in the East Hall. The nuclear physics programme at ISOLDE should start up on 9 April, while the Antiproton decelerator should start again in the second half of April.

    2018 is an important year for the collaborations using CERN’s accelerators, as it will be the last year of Run 2. In December, the accelerator complex will be shut down for two years of upgrade work aimed at improving performance further still and preparing for the High-Luminosity LHC.

    Accelerator hibernation ends

    9 Mar 2018
    Achintya Rao

    Today, 9 March, marks the end of CERN’s annual winter shut down. The Laboratory’s massive accelerator complex will soon begin to lumber out of its winter hibernation and resume accelerating and colliding particles.

    But while the Large Hadron Collider (LHC) has not been filled with protons since the Year-End Technical Stop (YETS) began on 4 December 2017, its tunnels and experimental caverns have been packed with people performing maintenance and repairs as well as testing components for future accelerators.

    Today, CERN’s Engineering department hands the accelerator complex back to the Beams department, who will commence hardware commissioning for 2018. This commissioning will culminate in the restart of the LHC, planned for early April.

    See the full article and following articles here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New

    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    LHC

    CERN LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles

    OTHER PROJECTS AT CERN

    CERN AEGIS

    CERN ALPHA

    CERN ALPHA

    CERN AMS

    CERN ACACUSA

    CERN ASACUSA

    CERN ATRAP

    CERN ATRAP

    CERN AWAKE

    CERN AWAKE

    CERN CAST

    CERN CAST Axion Solar Telescope

    CERN CLOUD

    CERN CLOUD

    CERN COMPASS

    CERN COMPASS

    CERN DIRAC

    CERN DIRAC

    CERN ISOLDE

    CERN ISOLDE

    CERN LHCf

    CERN LHCf

    CERN NA62

    CERN NA62

    CERN NTOF

    CERN TOTEM

    CERN UA9

     
  • richardmitnick 2:03 pm on April 12, 2018 Permalink | Reply
    Tags: , Heavy dark matter and PeV neutrinos: are they related?, , Particle Physics,   

    From U Wisconsin IceCube: “Heavy dark matter and PeV neutrinos: are they related?” 

    U Wisconsin ICECUBE neutrino detector at the South Pole

    IceCube neutrino detector interior

    IceCube Gen-2 DeepCore

    The existence of dark matter was proposed to explain gravitational effects of objects such as galaxies that could not be described by the constituents of so-called “normal” matter—electrons, neutrons, and protons. But dark matter searches have so far been futile. A proposed solution is a new, heavy dark matter particle that is long-lived but not necessarily on cosmic timescales.

    This scenario is especially interesting for IceCube because the decay of dark matter can produce high-energy neutrinos. And some models predict that some or all of the highest energy neutrinos seen in IceCube could be the result of such decay.

    The IceCube Collaboration has tested a few of these models and found no evidence that the high-energy neutrinos can be attributed to the decay of heavy dark matter particles. This nondetection resulted in a new lower limit of seconds—about 10 billion times the age of the universe—for the lifetime of dark matter particles with a mass of 10 TeV or above. The paper [Search for neutrinos from decaying dark matter with IceCube,” The IceCube Collaboration: M. G. Aartsen et al.] summarizing these results has just been submitted to the European Physical Journal C.

    1
    Comparison of the lower lifetime limits with results obtained from gamma-ray telescopes: HAWC (Dwarf Spheroidal Galaxies), HAWC (Galactic Halo/Center) and Fermi/LAT. Image: IceCube Collaboration

    HAWC High Altitude Cherenkov Experiment, located on the flanks of the Sierra Negra volcano in the Mexican state of Puebla at an altitude of 4100 meters, at WikiMiniAtlas 18°59′41″N 97°18′30.6″W. searches for cosmic rays

    NASA/Fermi Gamma Ray Space Telescope


    NASA/Fermi LAT

    Following the current understanding of fundamental interactions, all matter is unstable—even protons are expected to decay, although we might never see the decay of one since its lifetime is about times the age of the universe.

    Relic particles that may make up galactic and extragalactic dark matter could have lifetimes short enough to allow us detect the high-energy neutrinos that they would inevitably produce. Indeed, several theoretical models ascribe the cosmic neutrino signal detected by IceCube at TeV-PeV energies to the decay of heavy dark matter.

    IceCube searched for heavy dark matter in two independent measurements—one using six years of muon-neutrino tracks from the Northern Hemisphere and the other using two years of all-flavor neutrino cascades from the full sky—and found that if dark matter neutrinos exist, then only 1 in every 10 billion dark matter particles could have decayed by now. These results also prove that IceCube is a high-precision particle detector that can rule out, or at least constrain, dark matter theoretical models.

    IceCube data has been fitted with different combinations of theoretical predictions for dark matter and a diffuse astrophysical component. “Using both tracks and cascades, data favors a small but nonsignificant contribution from dark matter,” explains Jöran Stettner, a graduate student at RWTH Aachen University in Germany and main author of this work. “However, adding a dark matter contribution does not significantly improve the description of the observed astrophysical neutrinos,” adds Stettner

    This nondetection is used to set the strongest bounds to date on the minimal lifetime of dark matter particles with masses above 10 TeV. “To explain that we have not seen neutrinos from the decay of heavy dark matter, the lifetime of the hypothetical particle has to be much larger than the age of the universe,” says Hrvoje Dujmovic, a graduate student from Sungkyunkwan University in Korea and also main author of this paper.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    IceCube is a particle detector at the South Pole that records the interactions of a nearly massless sub-atomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars. The IceCube telescope is a powerful tool to search for dark matter, and could reveal the new physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. IceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice.

     
  • richardmitnick 5:42 pm on April 11, 2018 Permalink | Reply
    Tags: , , , , , Particle Physics,   

    From Symmetry: “Right on target” 

    Symmetry Mag
    Symmetry

    04/11/18
    Sarah Lawhun

    1
    Patrick Hurh

    These hardy physics components live at the center of particle production.

    For some, a target is part of a game of darts. For others, it’s a retail chain. In particle physics, it’s the site of an intense, complex environment that plays a crucial role in generating the universe’s smallest components for scientists to study.

    The target is an unsung player in particle physics experiments, often taking a back seat to scene-stealing light-speed particle beams and giant particle detectors. Yet many experiments wouldn’t exist without a target. And, make no mistake, a target that holds its own is a valuable player.

    Scientists and engineers at Fermilab [FNAL] are currently investigating targets for the study of neutrinos—mysterious particles that could hold the key to the universe’s evolution.

    Intense interactions

    The typical particle physics experiment is set up in one of two ways. In the first, two energetic particle beams collide into each other, generating a shower of other particles for scientists to study.

    In the second, the particle beam strikes a stationary, solid material—the target. In this fixed-target setup, the powerful meeting produces the particle shower.

    As the crash pad for intense beams, a target requires a hardy constitution. It has to withstand repeated onslaughts of high-power beams and hold up under hot temperatures.

    You might think that, as stalwart players in the play of particle production, targets would look like a fortress wall (or maybe you imagined dartboard). But targets take different shapes—long and thin, bulky and wide. They’re also made of different materials, depending on the kind of particle one wants to make. They can be made of metal, water or even specially designed nanofibers.

    In a fixed-target experiment, the beam—say, a proton beam—races toward the target, striking it. Protons in the beam interact with the target material’s nuclei, and the resulting particles shoot away from the target in all directions. Magnets then funnel and corral some of these newly born particles to a detector, where scientists measure their fundamental properties.

    The particle birthplace

    The particles that emerge from the beam-target interaction depend in large part on the target material. Consider Fermilab neutrino experiments.

    In these experiments, after the protons strike the target, some of the particles in the subsequent particle shower decay—or transform—into neutrinos.

    The target has to be made of just the right stuff.

    “Targets are crucial for particle physics research,” says Fermilab scientist Bob Zwaska. “They allow us to create all of these new particles, such as neutrinos, that we want to study.”

    Graphite is a goldilocks material for neutrino targets. If kept at the right temperature while in the proton beam, the graphite generates particles of just the right energy to be able to decay into neutrinos.

    For neutron targets, such as that at the Spallation Neutron Source at Oak Ridge National Laboratory [ORNL], heavier metals such as mercury are used instead.

    ORNL Spallation Neutron Source


    ORNL Spallation Neutron Source

    Maximum interaction is the goal of a target’s design. The target for Fermilab’s NOvA neutrino experiment, for example, is a straight row—about the length of your leg—of graphite fins that resemble tall dominoes.

    FNAL NOvA Near Detector


    FNAL/NOvA experiment map

    The proton beam barrels down its axis, and every encounter with a fin produces an interaction. The thin shape of the target ensures that few of the particles shooting off after collision are reabsorbed back into the target.

    Robust targets

    “As long as the scientists have the particles they need to study, they’re happy. But down the line, sometimes the targets become damaged,” says Fermilab engineer Patrick Hurh. In such cases, engineers have to turn down—or occasionally turn off—the beam power. “If the beam isn’t at full capacity or is turned off, we’re not producing as many particles as we can for science.”

    The more protons that are packed into the beam, the more interactions they have with the target, and the more particles that are produced for research. So targets need to be in tip-top shape as much as possible. This usually means replacing targets as they wear down, but engineers are always exploring ways of improving target resistance, whether it’s through design or material.

    Consider what targets are up against. It isn’t only high-energy collisions—the kinds of interactions that produce particles for study—that targets endure.

    Lower-energy interactions can have long-term, negative impacts on a target, building up heat energy inside it. As the target material rises in temperature, it becomes more vulnerable to cracking. Expanding warm areas hammer against cool areas, creating waves of energy that destabilize its structure.

    Some of the collisions in a high-energy beam can also create lightweight elements such as hydrogen or helium. These gases build up over time, creating bubbles and making the target less resistant to damage.

    A proton from the beam can even knock off an entire atom, disrupting the target’s crystal structure and causing it to lose durability.

    Clearly, being a target is no picnic, so scientists and engineers are always improving targets to better roll with a punch.

    For example, graphite, used in Fermilab’s neutrino experiments, is resistant to thermal strain. And, since it is porous, built-up gases that might normally wedge themselves between atoms and disrupt their arrangement may instead migrate to open areas in the atomic structure. The graphite is able to remain stable and withstand the waves of energy from the proton beam.

    Engineers also find ways to maintain a constant target temperature. They design it so that it’s easy to keep cool, integrating additional cooling instruments into the target design. For example, external water tubes help cool the target for Fermilab’s NOvA neutrino experiment.

    Targets for intense neutrino beams

    At Fermilab, scientists and engineers are also testing new designs for what will be the lab’s most powerful proton beam—the beam for the laboratory’s flagship Long-Baseline Neutrino Facility and Deep Underground Neutrino Experiment, known as LBNF/DUNE.

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA


    FNAL DUNE Argon tank at SURF


    Surf-Dune/LBNF Caverns at Sanford



    SURF building in Lead SD USA

    LBNF/DUNE is scheduled to begin operation in the 2020s. The experiment requires an intense beam of high-energy neutrinos—the most intense in the world. Only the most powerful proton beam can give rise to the quantities of neutrinos LBNF/DUNE needs.

    Scientists are currently in the early testing stages for LBNF/DUNE targets, investigating materials that can withstand the high-power protons. Currently in the running are beryllium and graphite, which they’re stretching to their limits. Once they conclusively determine which material comes out on top, they’ll move to the design prototyping phase. So far, most of their tests are pointing to graphite as the best choice.

    Targets will continue to evolve and adapt. LBNF/DUNE provides just one example of next-generation targets.

    “Our research isn’t just guiding the design for LBNF/DUNE,” Hurh says. “It’s for the science itself. There will always be different and more powerful particle beams, and targets will evolve to meet the challenge.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 2:42 pm on April 10, 2018 Permalink | Reply
    Tags: , , , , Now the question is what if there is a whole sector of undiscovered particles that cannot communicate with our standard particles but can interact with the Higgs boson?, , Particle Physics, , , Theorists predict that about 90 percent of Higgs bosons are created through gluon fusion   

    From Symmetry: “How to make a Higgs boson” 

    Symmetry Mag
    Symmetry

    04/10/18
    Sarah Charley

    CERN CMS Higgs Event


    CERN ATLAS Higgs Event

    It doesn’t seem like collisions of particles with no mass should be able to produce the “mass-giving” boson, the Higgs. But every other second at the LHC, they do.

    Einstein’s most famous theory, often written as E=mc2, tells us that energy and matter are two sides of the same coin.

    The Large Hadron Collider uses this principle to convert the energy contained within ordinary particles into new particles that are difficult to find in nature—particles like the Higgs boson, which is so massive that it almost immediately decays into pairs of lighter, more stable particles.

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    But not just any collision can create a Higgs boson.

    “The Higgs is not just created from a ‘poof’ of energy,” says Laura Dodd, a researcher at the University of Wisconsin, Madison. “Particles follow a strict set of laws that dictate how they can form, decay and interact.”

    One of these laws states that Higgs bosons can be produced only by particles that interact with the Higgs field—in other words, particles with mass.

    The Higgs field is like an invisible spider’s web that permeates all of space. As particles travel through it, some get tangled in the sticky tendrils, a process that makes them gain mass and slow down. But for other particles—such as photons and gluons—this web is completely transparent, and they glide through unhindered.

    Given enough energy, the particles wrapped in the Higgs field can transfer their energy into it and kick out a Higgs boson. Because massless particles do not interact with the Higgs field, it would make sense to say that they can’t create a Higgs. But scientists at the LHC would beg to differ.

    The LHC accelerates protons around its 17-mile circumference to just under the speed of light and then brings them into head-on collisions at four intersections along its ring. Protons are not fundamental particles, particles that cannot be broken down into any smaller constituent pieces. Rather they are made up of gluons and quarks.

    As two pepped-up protons pass through each other, it’s usually pairs of massless gluons that infuse invisible fields with their combined energy and excite other particles into existence—and that includes Higgs bosons.

    __________________________________________________________

    We know that particles follow strict rules about who can talk to whom.
    __________________________________________________________

    How? Gluons have found a way to cheat.

    “It would be impossible to generate Higgs bosons with gluons if the collisions in the LHC were a simple, one-step processes,” says Richard Ruiz, a theorist at Durham University’s Institute for Particle Physics Phenomenology.

    Luckily, they aren’t.

    Gluons can momentarily “launder” their energy to a virtual particle, which converts the gluon’s energy into mass. If two gluons produce a pair of virtual top quarks, the tops can recombine and annihilate into a Higgs boson.

    To be clear, virtual particles are not stable particles at all, but rather irregular disturbances in quantum mechanical fields that exist in a half-baked state for an incredibly short period of time. If a real particle were a thriving business, then a virtual particle would be a shell company.

    Theorists predict that about 90 percent of Higgs bosons are created through gluon fusion. The probability of two gluons colliding, creating a top quark-antitop pair and propitiously producing a Higgs is roughly one in 2 billion. However, because the LHC generates 10 million proton collisions every second, the odds are in scientists’ favor and the production rate for Higgs bosons is roughly one every two seconds.

    Shortly after the Higgs discovery, scientists were mostly focused on what happens to Higgs bosons after they decay, according to Dodd.

    “But now that we have more data and a better understanding of the Higgs, we’re starting to look closer at the collision byproducts to better understand how frequently the Higgs is produced through the different mechanisms,” she says.

    The Standard Model of particle physics predicts that almost all Higgs bosons are produced through one of four possible processes.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.


    Standard Model of Particle Physics from Symmetry Magazine

    What scientists would love to see are Higgs bosons being created in a way that the Standard Model of particle physics does not predict, such as in the decay of a new particle. Breaking the known rules would show that there is more going on than physicists previously understood.

    “We know that particles follow strict rules about who can talk to whom because we’ve seen this time and time again during our experiments,” Ruiz says. “So now the question is, what if there is a whole sector of undiscovered particles that cannot communicate with our standard particles but can interact with the Higgs boson?”

    Scientists are keeping an eye out for anything unexpected, such as an excess of certain particles radiating from a collision or decay paths that occur more or less frequently than scientists predicted. These indicators could point to undiscovered heavy particles morphing into Higgs bosons.

    At the same time, to find hints of unexpected ingredients in the chain reactions that sometimes make Higgs bosons, scientists must know very precisely what they should expect.

    “We have fantastic mathematical models that predict all this, and we know what both sides of the equations are,” Ruiz says. “Now we need to experimentally test these predictions to see if everything adds up, and if not, figure out what those extra missing variables might be.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
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