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Standard Model Festival
Standard Model festival The Hamburg Lepîon-Photon Symposium also marked the tenth anniversary of the discovery at Fermilab of the upsilon particle (beauty quark and antiquark bound together). At a Fermilab celebration of the discovery earlier this year were (left to right) Alvin Tollestrup, Sandy Anderson (with balloon), Hwa Yoh, Leon Lederman, Janine Tollestrup, Drummond Rennie, Martyl Langsdorf and Vivian Bull. The 'Standard Model' of modern particle physics, with the quantum chromodynamics (QCD) theory of inter-quark forces superimposed on the unified electroweak picture, is still unchallenged, but it is not the end of physics. This was the message at the big International Symposium on Lepton and Photon Interactions at High Energies, held in Hamburg from 27-31 July. The conference is a celebration of the Standard Model', admitted Graham Ross of Oxford, given the task of looking beyond. He pointed out a few interesting clouds on the horizon, and echoed the in creasing belief that experiments at higher collision energies (1000 GeV for constituent quarks inside nucléons or for electrons) would probe deep inside the Standard Model and reveal some thing new. Carlo Rubbia of CERN flew in at the end of the meeting with some suggestions for future machines to explore these far horizons. 'However our preoccupation with high energy should not exclude other interesting topics,' he warned, mentioning solar neutrino dronic events per day, and are plained single muons accompany studies, particle mixing, CP viola providing interesting new informa ing produced hadrons, reported tion, the search for proton decay tion to take over where the elec by some studies at the PETRA ring and supernova detection ('We tron-positron machines at Stanford at DESY (see September issue, should be better prepared next (US) and DESY (Hamburg) left off. -
Discovery of Gluon
Discovery of the Gluon Physics 290E Seminar, Spring 2020 Outline – Knowledge known at the time – Theory behind the discovery of the gluon – Key predicted interactions – Jet properties – Relevant experiments – Analysis techniques – Experimental results – Current research pertaining to gluons – Conclusion Knowledge known at the time The year is 1978, During this time, particle physics was arguable a mature subject. 5 of the 6 quarks were discovered by this point (the bottom quark being the most recent), and the only gauge boson that was known was the photon. There was also a theory of the strong interaction, quantum chromodynamics, that had been developed up to this point by Yang, Mills, Gell-Mann, Fritzsch, Leutwyler, and others. Trying to understand the structure of hadrons. Gluons can self-interact! Theory behind the discovery Analogous to QED, the strong interaction between quarks and gluons with a gauge group of SU(3) symmetry is known as quantum chromodynamics (QCD). Where the force mediating particle is the gluon. In QCD, we have some quite particular features such as asymptotic freedom and confinement. 4 α Short range:V (r) = − s QCD 3 r 4 α Long range: V (r) = − s + kr QCD 3 r (Between a quark and antiquark) Quantum fluctuations cause the bare color charge to be screened causes coupling strength to vary. Features are important for an understanding of jet formation. Theory behind the discovery John Ellis postulated the search for the gluon through bremsstrahlung radiation in electron- proton annihilation processes in 1976. Such a process will produce jets of hadrons: e−e+ qq¯g Furthermore, Mary Gaillard, Graham Ross, and John Ellis wrote a paper (“Search for Gluons in e+e- Annihilation.”) that described that the PETRA collider at DESY and the PEP collider at SLAC should be able to observe this process. -
Team Science and Individual Recognition
Individual Recognition in Large Collaborations Archana SHARMA CERN CH1211 Geneva Switzerland ALBA Synchrotron Barcelona - July 19-20, 2018 Group Leader Research Post Doc Assistant Staff Student Staff Staff Student Staff Pierre Curie Assistant Petit Marie Curie Hans Geiger and Ernest Rutherford th th 19 and 20 Century A HEP Group in 70s ALBA Synchrotron Barcelona - July 19-20, 2018 2 30-50 physicists from 10-15 Participating Institutions UA1 & UA2 1980’s 5-8 countries. Natural evolution of Individual Recognition Important component of career and job security 3 1990’s 300-550 physicists from 20-30 participating Institutions in 15-20 countries DELPHI L3 ALEPH OPAL 1990’s 300-550 physicists from 20-30 participating Institutions in 15-20 countries. DELPHI L3 Need for Large Collaborations an important component of scientific progress But are we diluting Individual Recognition ? ALEPH OPAL 2000’s LHC Experiments Up to 5500 physicists from 150-200 participating 2010’s Institutions from 40-50 countries. 2000’s LHC Experiments Leadership emanating from previous generation experiments 2010’s Caveats in Individual Recognition? Large collaborations are successful ! • Clear definitions, agreements on roles • Open communication within teams • Recognition and respect • Addressing problems cooperatively as they occur. • Group goals are placed above personal satisfaction and/or recognition. • Absolute willingness to forgiving for mistakes • Challenges? ALBA Synchrotron Barcelona - July 19-20, 2018 • Particularly for young budding 8 careers ? Guido Tonelli SCARF Autonomy – is “the perception of exerting control over one’s environment; a sensation of having choices.” Providing multiple choices is preferable NA1, NA7, CDF, ALEPH CMS Spokesperson Top: CERN NA close to the UA1 target (1977) First silicon and germanium µStrip active targets for the study of charmed particles. -
A View on the European Strategy for Particle Physics
A VieW ON THE EurOPEAN StrATEGY FOR Particle Physics Contact Person: Michel SpirO ([email protected]) Worldwide, THE PARTICLE PHYSICS AND ACCELERATOR COMMUNITY IS AbstrACT VERY ACTIVELY WORKING TOWARDS THE NEXT MAJOR FACILITY. Based ON THE DESIGNS AND PERFORMANCE OF LINEAR AND CIRCULAR E+E* COLLIDERS IN THE 90 (Z) TO 365 (aboVE top-antitop) GeV CENTRe-of-mass ENERGY Range, WE CONSIDER A CIRCULAR COLLIDER AT CERN TO BE THE MOST ATTRACTIVE option. IT IS ALSO AN INVESTMENT IN THE FUTURE FOR A POSSIBLE LATER STAGE AS A 100 TeV HADRON collider. 1 OF5 A VieW ON THE EurOPEAN StrATEGY FOR Particle Physics The COMMUNITY OF PARTICLE PHYSICISTS IS PREPARING THE NEXT EurOPEAN Strat- EGY. IT WILL CONSIDER RECENT advances, SUCH AS THE IMPRESSIVE SUCCESS OF THE StandarD Model AND THE Higgs BOSON DISCOVERY, BUT ALSO ADDRESS funda- MENTAL QUESTIONS THAT REMAIN open. Exploring THE “UNIQUENESS” OF THE Higgs BOSON AND PLACING THE EMERGING UNDERSTANDING IN A LARGER CONTEXT (and NEW physics?) WILL BE ONE KEY ITEM ON OUR to-do list. While THE ONGOING AND PLANNED LHC EXPLOITATION WILL PROVIDE CONSIDERABLE PROGRess, IT IS GENERALLY AGREED THAT A NEW FACILITY, SOMETIMES DUBBED A “Higgs Factory”, WILL BE REQUIRED FOR THE AMBITIOUS PROGRAMME OF PRECISION MEASURements. CurrENTLY, THIS IS OBVIOUSLY THE DOMAIN OF AN E+E* collider. Linear OR Circular: THAT IS THE question. The OffERS THE POSSIBILITY TO Extend, IN principle, THE Linear Collider AVAILABLE COLLISION ENERGY AS PHYSICS indicates, AND ELECTRIC POWER AND fund- ING ALLOws. Longitudinal BEAM POLARIZATION CAN BE Exploited. IT HAS A disadvantage: ONLY ONE EXPERIMENT WILL TAKE DATA AT A GIVEN time. -
A Physicist Goes in Search of Our Origins
Books & arts researchers and practitioners, the book charts rooted. Why? Because using data to inform we need to address the source of the bias. a slow, steady, complex progress, with many automated decisions often ignores the con- This will be done not through technological lows and some incredible highs. texts, emotions and relationships that are core fixes, but by education and social change. At We meet people such as Rich Caruana, now to human choices. the same time, research is needed to address senior principal researcher at Microsoft in Data are not raw materials. They are always the field’s perverse dependence on correla- Redmond, Washington, who was asked as a about the past, and they reflect the beliefs, tions in data. Current AI identifies patterns, graduate student to glance at something that practices and biases of those who create and not meaning. led to his life’s work — optimizing data cluster- collect them. Yet current application of auto- Meticulously researched and superbly writ- ing and compression to make models that are mated decision-making is informed more by ten, these books ultimately hold up a mirror. both intelligible and accurate. And we walk efficiency and economic benefits than by its They show that the responsible — ethical, legal along the beach with Marc Bellemare, who pio- effects on people. and beneficial — development and use of AI is neered reinforcement learning while working Worse, most approaches to AI empower not about technology. It is about us: how we with games for the Atari console and is now at those who have the data and the computa- want our world to be; how we prioritize human Google Research in Montreal, Canada. -
Mass Determination of New Particle States
Mass Determination of New Particle States Mario A Serna Jr Wadham College University of Oxford arXiv:0905.1425v1 [hep-ph] 9 May 2009 A thesis submitted for the degree of Doctor of Philosophy Trinity 2008 This thesis is dedicated to my wife for joyfully supporting me and our daughter while I studied. Mass Determination of New Particle States Mario Andres Serna Jr Wadham College Thesis submitted for the degree of Doctor of Philosophy Trinity Term 2008 Abstract We study theoretical and experimental facets of mass determination of new particle states. Assuming supersymmetry, we update the quark and lepton mass matri- ces at the grand unification scale accounting for threshold corrections enhanced by large ratios of the vacuum expectation value of the two supersymmetric Higgs fields vu=vd ≡ tan β. From the hypothesis that quark and lepton masses satisfy a classic set of relationships suggested in some Grand Unified Theories (GUTs), we predict tan β needs to be large, and the gluino's soft mass needs to have the opposite sign to the wino's soft mass. Existing tools to measure the phase of the gluino's mass at upcoming hadron colliders require model-independent, kinematic techniques to determine the masses of the new supersymmetric particle states. The mass deter- mination is made difficult because supersymmetry is likely to have a dark-matter particle which will be invisible to the detector, and because the reference frame and energy of the parton collisions are unknown at hadron colliders. We discuss the current techniques to determine the mass of invisible particles. We review the transverse mass kinematic variable MT 2 and the use of invariant-mass edges to find relationships between masses. -
Lawrence Berkeley Laboratory UNIVERSITY of CALIFORNIA
t.,t(> ~Yd LBL- 2 0 7 4 7 ~ I Lawrence Berkeley Laboratory UNIVERSITY OF CALIFORNIA 1 . '' r, ·) t· Physics Division ·• ... ' ;..; ;] 1986 :BRARY AND -"'TS S'=r..,...f('" • Lectures given at the Summer School on 'Architecture of Fundamental Interactions', Les Houches, France, July-August 1985 THE QUEST FOR SUPERSYMMETRY I. Hinchliffe December 1985 - Prepared for the U.S. Department of Energy under Contract DE-AC03-76SF00098 DISCLAIMER This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor the Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or the Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or the Regents of the University of California. "") •.~ t ~ -- December 1985 LBL-20747 Table of Contents 1. Introduction THE QUEST FOR SUPERSYMMETRY* 2. Cosmological Bounds 3. Supersymmetry in e+ e- Annihilation Lectures given at the Summer School on 'Architecture of Fundamental 4. -
Memories of a Theoretical Physicist
Memories of a Theoretical Physicist Joseph Polchinski Kavli Institute for Theoretical Physics University of California Santa Barbara, CA 93106-4030 USA Foreword: While I was dealing with a brain injury and finding it difficult to work, two friends (Derek Westen, a friend of the KITP, and Steve Shenker, with whom I was recently collaborating), suggested that a new direction might be good. Steve in particular regarded me as a good writer and suggested that I try that. I quickly took to Steve's suggestion. Having only two bodies of knowledge, myself and physics, I decided to write an autobiography about my development as a theoretical physicist. This is not written for any particular audience, but just to give myself a goal. It will probably have too much physics for a nontechnical reader, and too little for a physicist, but perhaps there with be different things for each. Parts may be tedious. But it is somewhat unique, I think, a blow-by-blow history of where I started and where I got to. Probably the target audience is theoretical physicists, especially young ones, who may enjoy comparing my struggles with their own.1 Some dis- claimers: This is based on my own memories, jogged by the arXiv and IN- SPIRE. There will surely be errors and omissions. And note the title: this is about my memories, which will be different for other people. Also, it would not be possible for me to mention all the authors whose work might intersect mine, so this should not be treated as a reference work. -
Annual Report 2012
J-PARC A N N U A L REPOR T 2 O 1 2 JA PA N PR O T O N A CCEL E R AT O R RE S E A RC H C O MPL E X J-PARC Annual Report 2012 Contents Preface ………………………………………………………………………………………………………… 1 Accelerators …………………………………………………………………………………………………… 3 Overview …………………………………………………………………………………………………… 4 LINAC ……………………………………………………………………………………………………… 5 RCS ………………………………………………………………………………………………………… 7 MR ………………………………………………………………………………………………………… 9 Materials and Life Science Experimental Facility ……………………………………………………………… 13 Overview ………………………………………………………………………………………………… 14 Neutron Source ………………………………………………………………………………………… 16 Neutron Science ………………………………………………………………………………………… 18 Muon Science …………………………………………………………………………………………… 22 Neutron Device ………………………………………………………………………………………… 24 Particle and Nuclear Physics …………………………………………………………………………………… 25 Hadron and Nuclear Physics …………………………………………………………………………… 26 Kaon Physics …………………………………………………………………………………………… 27 Muon Physics …………………………………………………………………………………………… 28 Neutrino Experimental Facility ………………………………………………………………………… 28 Cryogenics Section …………………………………………………………………………………………… 31 Overview ………………………………………………………………………………………………… 32 Superconducting Magnet System for the T2K Beamline ………………………………………………… 32 Superconducting Kaon Spectrometer (SKS) ……………………………………………………………… 32 The Superconducting Magnet System for the Muon Beam Line at MLF ………………………………… 33 Cryogen Supply and Technical Support ………………………………………………………………… 33 R&D for the J-PARC Project: COMET ……………………………………………………………………… 34 R&D for the Future J-PARC Project: New -
Pos(EPS-HEP2019)444
The use of narration and art in the Public Communication of Science PoS(EPS-HEP2019)444 Francesca Scianitti1 † INFN Communications Office Piazza dei Caprettari 70, Rome, Italy E-mail: [email protected] Working as a laboratory for unconventional scientific communication, in the last decade the INFN Communications Office [1] has developed innovative formats of public events, in which the performing arts are intertwined with the scientific narrative. This process was born with the goal of involving a wide variety of audiences with Particle Physics, Cosmology and Technology and increase the awareness in the research and innovation processes lead by INFN and the scientific community as a whole. The underlying idea is that a narrative approach in public events, accompanied by experiences solicited by the artistic language, can help the audience to unveil connections in the interpretation of reality, thus opening unexpected scenarios for the acquisition of knowledge. If well designed and build on verified content, these formats can offer tactics to properly engage non-expert audiences [2]. Case studies of innovative formats are presented, as “Cosmic Tale", a conference-show about the universe birth and evolution, offered to more than 6000 people in the period from 2016 to 2019 (7 live replicas). The narrative structure of Cosmic Tale is based on the intertwining of dialogues, videos, readings and music, and moves along a well-defined storyboard, supported also by a cartoon story. More recently, the INFN and the Italian Space Agency (ASI) experimented with a format based on monologues about the same story - the first detection of gravitational waves from the coalescence of neutron stars - told from three different points of view (space satellites, terrestrial telescopes and gravitational wave detectors) and interlaced with jazz music played by professional and well-known musicians. -
The Shape of Inner Space Provides a Vibrant Tour Through the Strange and Wondrous Possibility SPACE INNER
SCIENCE/MATHEMATICS SHING-TUNG $30.00 US / $36.00 CAN Praise for YAU & and the STEVE NADIS STRING THEORY THE SHAPE OF tring theory—meant to reconcile the INNER SPACE incompatibility of our two most successful GEOMETRY of the UNIVERSE’S theories of physics, general relativity and “The Shape of Inner Space provides a vibrant tour through the strange and wondrous possibility INNER SPACE THE quantum mechanics—holds that the particles that the three spatial dimensions we see may not be the only ones that exist. Told by one of the Sand forces of nature are the result of the vibrations of tiny masters of the subject, the book gives an in-depth account of one of the most exciting HIDDEN DIMENSIONS “strings,” and that we live in a universe of ten dimensions, and controversial developments in modern theoretical physics.” —BRIAN GREENE, Professor of © Susan Towne Gilbert © Susan Towne four of which we can experience, and six that are curled up Mathematics & Physics, Columbia University, SHAPE in elaborate, twisted shapes called Calabi-Yau manifolds. Shing-Tung Yau author of The Fabric of the Cosmos and The Elegant Universe has been a professor of mathematics at Harvard since These spaces are so minuscule we’ll probably never see 1987 and is the current department chair. Yau is the winner “Einstein’s vision of physical laws emerging from the shape of space has been expanded by the higher them directly; nevertheless, the geometry of this secret dimensions of string theory. This vision has transformed not only modern physics, but also modern of the Fields Medal, the National Medal of Science, the realm may hold the key to the most important physical mathematics. -
No Slide Title
The discovery of a (the) Higgs boson by CMS. Guido Tonelli (CERN, INFN&University of Pisa SIF_2013. G. Tonelli, CERN/INFN/UNIPI September 23 SIF_TRIESTE-27, Trieste (Italy) . September 23 2013 1 A ~50 year old elegant conjecture… G. Tonelli, CERN/INFN/UNIPI SIF_TRIESTE September 23 2013 2 …with profound implications. The exact symmetries of the Lagrangian relating the weak and electromagnetic interactions are broken by the vacuum: the photon remains massless while the W and Z boson becomes massive. A mechanism “ a la Yukawa” gives mass to fermions. A new scalar field pervades every corner of our universe. G. Tonelli, CERN/INFN/UNIPI SIF_TRIESTE September 23 2013 3 LHC: a beautiful machine +TOTEM 1232 superconducting dipoles 15m long at 1.9 K, B=8.33 T Inner coil diameter = 56 mm Max. beam-energy 7 TeV ( 7xTEVATRON) 34 -2 -1 Design Luminosity 10 cm s (>100x TEVATRON) +LHCf Bunch spacing 24.95 ns Particles/bunch 1.1 1011 Stored E/beam 362 MJ After the incident on the splices in 2008 3.5-4 TeV max beam energy Also : Lead Ions operation Energy/nucleon 2.76 TeV / u 50ns bunch spacing, high “pile-up” Total initial lumi 1027 cm-2 s-1 Max L~5-7x1033 cm-2s-1 G. Tonelli, CERN/INFN/UNIPI SIF_TRIESTE September 23 2013 4 The Compact Muon Solenoid (CMS) SUPERCONDUCTING CALORIMETERS ECAL Scintillating PbWO4 HCAL Plastic scintillator COIL Crystals copper sandwich Total weight : 12,500 t Overall diameter : 14.6 m Overall length : 21.6 m Magnetic field : 3.8 Tesla IRON YOKE TRACKERs MUON ENDCAPS MUON BARREL Silicon Microstrips Pixels Drift Tube Resistive Plate Cathode Strip Chambers (CSC) Chambers (DT) Chambers (RPC) Resistive Plate Chambers (RPC) G.