How Protons Interact with Their Exotic Siblings
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Quantum Field Theory*
Quantum Field Theory y Frank Wilczek Institute for Advanced Study, School of Natural Science, Olden Lane, Princeton, NJ 08540 I discuss the general principles underlying quantum eld theory, and attempt to identify its most profound consequences. The deep est of these consequences result from the in nite number of degrees of freedom invoked to implement lo cality.Imention a few of its most striking successes, b oth achieved and prosp ective. Possible limitation s of quantum eld theory are viewed in the light of its history. I. SURVEY Quantum eld theory is the framework in which the regnant theories of the electroweak and strong interactions, which together form the Standard Mo del, are formulated. Quantum electro dynamics (QED), b esides providing a com- plete foundation for atomic physics and chemistry, has supp orted calculations of physical quantities with unparalleled precision. The exp erimentally measured value of the magnetic dip ole moment of the muon, 11 (g 2) = 233 184 600 (1680) 10 ; (1) exp: for example, should b e compared with the theoretical prediction 11 (g 2) = 233 183 478 (308) 10 : (2) theor: In quantum chromo dynamics (QCD) we cannot, for the forseeable future, aspire to to comparable accuracy.Yet QCD provides di erent, and at least equally impressive, evidence for the validity of the basic principles of quantum eld theory. Indeed, b ecause in QCD the interactions are stronger, QCD manifests a wider variety of phenomena characteristic of quantum eld theory. These include esp ecially running of the e ective coupling with distance or energy scale and the phenomenon of con nement. -
THE STRONG INTERACTION by J
MISN-0-280 THE STRONG INTERACTION by J. R. Christman 1. Abstract . 1 2. Readings . 1 THE STRONG INTERACTION 3. Description a. General E®ects, Range, Lifetimes, Conserved Quantities . 1 b. Hadron Exchange: Exchanged Mass & Interaction Time . 1 s 0 c. Charge Exchange . 2 d L u 4. Hadron States a. Virtual Particles: Necessity, Examples . 3 - s u - S d e b. Open- and Closed-Channel States . 3 d n c. Comparison of Virtual and Real Decays . 4 d e 5. Resonance Particles L0 a. Particles as Resonances . .4 b. Overview of Resonance Particles . .5 - c. Resonance-Particle Symbols . 6 - _ e S p p- _ 6. Particle Names n T Y n e a. Baryon Names; , . 6 b. Meson Names; G-Parity, T , Y . 6 c. Evolution of Names . .7 d. The Berkeley Particle Data Group Hadron Tables . 7 7. Hadron Structure a. All Hadrons: Possible Exchange Particles . 8 b. The Excited State Hypothesis . 8 c. Quarks as Hadron Constituents . 8 Acknowledgments. .8 Project PHYSNET·Physics Bldg.·Michigan State University·East Lansing, MI 1 2 ID Sheet: MISN-0-280 THIS IS A DEVELOPMENTAL-STAGE PUBLICATION Title: The Strong Interaction OF PROJECT PHYSNET Author: J. R. Christman, Dept. of Physical Science, U. S. Coast Guard The goal of our project is to assist a network of educators and scientists in Academy, New London, CT transferring physics from one person to another. We support manuscript Version: 11/8/2001 Evaluation: Stage B1 processing and distribution, along with communication and information systems. We also work with employers to identify basic scienti¯c skills Length: 2 hr; 12 pages as well as physics topics that are needed in science and technology. -
Electron-Nucleon Scattering at LDMX for DUNE
Snowmass Letter of Intent: Snowmass Topical Groups: NF6, RF6, TF11 Electron-Nucleon Scattering at LDMX for DUNE Torsten Akesson1, Artur Ankowski2, Nikita Blinov3, Lene Kristian Bryngemark4, Pierfrancesco Butti2, Caterina Doglioni1, Craig Dukes5, Valentina Dutta6, Bertrand Echenard7, Thomas Eichlersmith8, Ralf Ehrlich5, Andrew Furmanski∗8, Niramay Gogate9, Mathew Graham2, Craig Group5, Alexander Friedland2, David Hitlin7, Vinay Hegde9, Christian Herwig3, Joseph Incandela6, Wesley Ketchumy3, Gordan Krnjaic3, Amina Li6, Shirley Liz2,3, Dexu Lin7, Jeremiah Mans8, Cristina Mantilla Suarez3, Phillip Masterson6, Martin Meier8, Sophie Middleton7, Omar Moreno2, Geoffrey Mullier1, Tim Nelson2, James Oyang7, Gianluca Petrillo2, Ruth Pottgen1, Stefan Prestel1, Luis Sarmiento1, Philip Schuster2, Hirohisa Tanaka2, Lauren Tompkins4, Natalia Toro2, Nhan Tran§3, and Andrew Whitbeck9 1Lund University 2Stanford Linear Accelerator Laboratory 3Fermi National Accelerator Laboratory 4Stanford University 5University of Virginia 6University of California Santa Barbara 7California Institute of Technology 8University of Minnesota 9Texas Tech University ABSTRACT We point out that the LDMX (Light Dark Matter eXperiment) detector design, conceived to search for sub-GeV dark matter, will also have very advantageous characteristics to pursue electron-nucleus scattering measurements of direct relevance to the neutrino program at DUNE and elsewhere. These characteristics include a 4-GeV electron beam, a precision tracker, electromagnetic and hadronic calorimeters with near 2p azimuthal acceptance from the forward beam axis out to 40◦ angle, and low reconstruction energy threshold. LDMX thus could provide (semi)exclusive cross section measurements, with∼ detailed information about final-state electrons, pions, protons, and neutrons. We compare the predictions of two widely used neutrino generators (GENIE, GiBUU) in the LDMX region of acceptance to illustrate the large modeling discrepancies in electron-nucleus interactions at DUNE-like kinematics. -
A Young Physicist's Guide to the Higgs Boson
A Young Physicist’s Guide to the Higgs Boson Tel Aviv University Future Scientists – CERN Tour Presented by Stephen Sekula Associate Professor of Experimental Particle Physics SMU, Dallas, TX Programme ● You have a problem in your theory: (why do you need the Higgs Particle?) ● How to Make a Higgs Particle (One-at-a-Time) ● How to See a Higgs Particle (Without fooling yourself too much) ● A View from the Shadows: What are the New Questions? (An Epilogue) Stephen J. Sekula - SMU 2/44 You Have a Problem in Your Theory Credit for the ideas/example in this section goes to Prof. Daniel Stolarski (Carleton University) The Usual Explanation Usual Statement: “You need the Higgs Particle to explain mass.” 2 F=ma F=G m1 m2 /r Most of the mass of matter lies in the nucleus of the atom, and most of the mass of the nucleus arises from “binding energy” - the strength of the force that holds particles together to form nuclei imparts mass-energy to the nucleus (ala E = mc2). Corrected Statement: “You need the Higgs Particle to explain fundamental mass.” (e.g. the electron’s mass) E2=m2 c4+ p2 c2→( p=0)→ E=mc2 Stephen J. Sekula - SMU 4/44 Yes, the Higgs is important for mass, but let’s try this... ● No doubt, the Higgs particle plays a role in fundamental mass (I will come back to this point) ● But, as students who’ve been exposed to introductory physics (mechanics, electricity and magnetism) and some modern physics topics (quantum mechanics and special relativity) you are more familiar with.. -
From Quark and Nucleon Correlations to Discrete Symmetry and Clustering
From quark and nucleon correlations to discrete symmetry and clustering in nuclei G. Musulmanbekov JINR, Dubna, RU-141980, Russia E-mail: [email protected] Abstract Starting with a quark model of nucleon structure in which the valence quarks are strongly correlated within a nucleon, the light nu- clei are constructed by assuming similar correlations of the quarks of neighboring nucleons. Applying the model to larger collections of nucleons reveals the emergence of the face-centered cubic (FCC) sym- metry at the nuclear level. Nuclei with closed shells possess octahedral symmetry. Binding of nucleons are provided by quark loops formed by three and four nucleon correlations. Quark loops are responsible for formation of exotic (borromean) nuclei, as well. The model unifies independent particle (shell) model, liquid-drop and cluster models. 1 Introduction arXiv:1708.04437v2 [nucl-th] 19 Sep 2017 Historically there are three well known conventional nuclear models based on different assumption about the phase state of the nucleus: the liquid-drop, shell (independent particle), and cluster models. The liquid-drop model re- quires a dense liquid nuclear interior (short mean-free-path, local nucleon interactions and space-occupying nucleons) in order to predict nuclear bind- ing energies, radii, collective oscillations, etc. In contrast, in the shell model each point nucleon moves in mean-field potential created by other nucleons; the model predicts the existence of nucleon orbitals and shell-like orbital- filling. The cluster models require the assumption of strong local-clustering 1 of particularly the 4-nucleon alpha-particle within a liquid or gaseous nuclear interior in order to make predictions about the ground and excited states of cluster configurations. -
First Results of the Cosmic Ray NUCLEON Experiment
Prepared for submission to JCAP First results of the cosmic ray NUCLEON experiment E. Atkin,a V. Bulatov,b V. Dorokhov,b N. Gorbunov,c;d S. Filippov,b V. Grebenyuk,c;d D. Karmanov,e I. Kovalev,e I. Kudryashov,e A. Kurganov,e M. Merkin,e A. Panov,e;1 D. Podorozhny,e D. Polkov,b S. Porokhovoy,c V. Shumikhin,a L. Sveshnikova,e A. Tkachenko,c;f L. Tkachev,c;d A. Turundaevskiy,e O. Vasiliev ande A. Voronine aNational Research Nuclear University “MEPhI”, Kashirskoe highway, 31. Moscow, 115409, Russia bSDB Automatika, Mamin-Sibiryak str, 145, Ekaterinburg, 620075, Russia cJoint Institute for Nuclear Research, Dubna, Joliot-Curie, 6, Moscow region, 141980, Russia d arXiv:1702.02352v2 [astro-ph.HE] 2 Jul 2018 “DUBNA” University, Universitetskaya str., 19, Dubna, Moscow region, 141980, Russia eSkobeltsyn Institute of Nuclear Physics, Moscow State University, 1(2), Leninskie gory, GSP-1, Moscow, 119991, Russia f Bogolyubov Institute for Theoretical Physics, 14-b Metrolohichna str., Kiev, 03143, Ukraine 1Corresponding author. E-mail: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], tfl[email protected], [email protected], [email protected], [email protected], [email protected], [email protected] Abstract. -
New Physics of Strong Interaction and Dark Universe
universe Review New Physics of Strong Interaction and Dark Universe Vitaly Beylin 1 , Maxim Khlopov 1,2,3,* , Vladimir Kuksa 1 and Nikolay Volchanskiy 1,4 1 Institute of Physics, Southern Federal University, Stachki 194, 344090 Rostov on Don, Russia; [email protected] (V.B.); [email protected] (V.K.); [email protected] (N.V.) 2 CNRS, Astroparticule et Cosmologie, Université de Paris, F-75013 Paris, France 3 National Research Nuclear University “MEPHI” (Moscow State Engineering Physics Institute), 31 Kashirskoe Chaussee, 115409 Moscow, Russia 4 Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Russia * Correspondence: [email protected]; Tel.:+33-676380567 Received: 18 September 2020; Accepted: 21 October 2020; Published: 26 October 2020 Abstract: The history of dark universe physics can be traced from processes in the very early universe to the modern dominance of dark matter and energy. Here, we review the possible nontrivial role of strong interactions in cosmological effects of new physics. In the case of ordinary QCD interaction, the existence of new stable colored particles such as new stable quarks leads to new exotic forms of matter, some of which can be candidates for dark matter. New QCD-like strong interactions lead to new stable composite candidates bound by QCD-like confinement. We put special emphasis on the effects of interaction between new stable hadrons and ordinary matter, formation of anomalous forms of cosmic rays and exotic forms of matter, like stable fractionally charged particles. The possible correlation of these effects with high energy neutrino and cosmic ray signatures opens the way to study new physics of strong interactions by its indirect multi-messenger astrophysical probes. -
Baryon and Lepton Number Anomalies in the Standard Model
Appendix A Baryon and Lepton Number Anomalies in the Standard Model A.1 Baryon Number Anomalies The introduction of a gauged baryon number leads to the inclusion of quantum anomalies in the theory, refer to Fig. 1.2. The anomalies, for the baryonic current, are given by the following, 2 For SU(3) U(1)B , ⎛ ⎞ 3 A (SU(3)2U(1) ) = Tr[λaλb B]=3 × ⎝ B − B ⎠ = 0. (A.1) 1 B 2 i i lef t right 2 For SU(2) U(1)B , 3 × 3 3 A (SU(2)2U(1) ) = Tr[τ aτ b B]= B = . (A.2) 2 B 2 Q 2 ( )2 ( ) For U 1 Y U 1 B , 3 A (U(1)2 U(1) ) = Tr[YYB]=3 × 3(2Y 2 B − Y 2 B − Y 2 B ) =− . (A.3) 3 Y B Q Q u u d d 2 ( )2 ( ) For U 1 BU 1 Y , A ( ( )2 ( ) ) = [ ]= × ( 2 − 2 − 2 ) = . 4 U 1 BU 1 Y Tr BBY 3 3 2BQYQ Bu Yu Bd Yd 0 (A.4) ( )3 For U 1 B , A ( ( )3 ) = [ ]= × ( 3 − 3 − 3) = . 5 U 1 B Tr BBB 3 3 2BQ Bu Bd 0 (A.5) © Springer International Publishing AG, part of Springer Nature 2018 133 N. D. Barrie, Cosmological Implications of Quantum Anomalies, Springer Theses, https://doi.org/10.1007/978-3-319-94715-0 134 Appendix A: Baryon and Lepton Number Anomalies in the Standard Model 2 Fig. A.1 1-Loop corrections to a SU(2) U(1)B , where the loop contains only left-handed quarks, ( )2 ( ) and b U 1 Y U 1 B where the loop contains only quarks For U(1)B , A6(U(1)B ) = Tr[B]=3 × 3(2BQ − Bu − Bd ) = 0, (A.6) where the factor of 3 × 3 is a result of there being three generations of quarks and three colours for each quark. -
14. Structure of Nuclei Particle and Nuclear Physics
14. Structure of Nuclei Particle and Nuclear Physics Dr. Tina Potter Dr. Tina Potter 14. Structure of Nuclei 1 In this section... Magic Numbers The Nuclear Shell Model Excited States Dr. Tina Potter 14. Structure of Nuclei 2 Magic Numbers Magic Numbers = 2; 8; 20; 28; 50; 82; 126... Nuclei with a magic number of Z and/or N are particularly stable, e.g. Binding energy per nucleon is large for magic numbers Doubly magic nuclei are especially stable. Dr. Tina Potter 14. Structure of Nuclei 3 Magic Numbers Other notable behaviour includes Greater abundance of isotopes and isotones for magic numbers e.g. Z = 20 has6 stable isotopes (average=2) Z = 50 has 10 stable isotopes (average=4) Odd A nuclei have small quadrupole moments when magic First excited states for magic nuclei higher than neighbours Large energy release in α, β decay when the daughter nucleus is magic Spontaneous neutron emitters have N = magic + 1 Nuclear radius shows only small change with Z, N at magic numbers. etc... etc... Dr. Tina Potter 14. Structure of Nuclei 4 Magic Numbers Analogy with atomic behaviour as electron shells fill. Atomic case - reminder Electrons move independently in central potential V (r) ∼ 1=r (Coulomb field of nucleus). Shells filled progressively according to Pauli exclusion principle. Chemical properties of an atom defined by valence (unpaired) electrons. Energy levels can be obtained (to first order) by solving Schr¨odinger equation for central potential. 1 E = n = principle quantum number n n2 Shell closure gives noble gas atoms. Are magic nuclei analogous to the noble gas atoms? Dr. -
Electron- Vs Neutrino-Nucleus Scattering
Electron- vs Neutrino-Nucleus Scattering Omar Benhar INFN and Department of Physics Universita` “La Sapienza” I-00185 Roma, Italy NUFACT11 University of Geneva, August 2nd, 2011 Neutrino-nucleus scattering . impact of the flux average . flux-averaged electron scattering x-section: a numerical experiment . contributions of reaction mechanisms other than quasi elastic single nucleon knock out to the MiniBooNE CCQE data sample Summary & Outlook Outline Electron scattering . standard data representation . theoretical description: the impulse approximation Omar Benhar (INFN, Roma) NUFACT11 Geneva 02/08/2011 2 / 24 Summary & Outlook Outline Electron scattering . standard data representation . theoretical description: the impulse approximation Neutrino-nucleus scattering . impact of the flux average . flux-averaged electron scattering x-section: a numerical experiment . contributions of reaction mechanisms other than quasi elastic single nucleon knock out to the MiniBooNE CCQE data sample Omar Benhar (INFN, Roma) NUFACT11 Geneva 02/08/2011 2 / 24 Outline Electron scattering . standard data representation . theoretical description: the impulse approximation Neutrino-nucleus scattering . impact of the flux average . flux-averaged electron scattering x-section: a numerical experiment . contributions of reaction mechanisms other than quasi elastic single nucleon knock out to the MiniBooNE CCQE data sample Summary & Outlook Omar Benhar (INFN, Roma) NUFACT11 Geneva 02/08/2011 2 / 24 The inclusive electron-nucleus x-section The x-section of the process e -
MIT at the Large Hadron Collider—Illuminating the High-Energy Frontier
Mit at the large hadron collider—Illuminating the high-energy frontier 40 ) roland | klute mit physics annual 2010 gunther roland and Markus Klute ver the last few decades, teams of physicists and engineers O all over the globe have worked on the components for one of the most complex machines ever built: the Large Hadron Collider (LHC) at the CERN laboratory in Geneva, Switzerland. Collaborations of thousands of scientists have assembled the giant particle detectors used to examine collisions of protons and nuclei at energies never before achieved in a labo- ratory. After initial tests proved successful in late 2009, the LHC physics program was launched in March 2010. Now the race is on to fulfill the LHC’s paradoxical mission: to complete the Stan- dard Model of particle physics by detecting its last missing piece, the Higgs boson, and to discover the building blocks of a more complete theory of nature to finally replace the Standard Model. The MIT team working on the Compact Muon Solenoid (CMS) experiment at the LHC stands at the forefront of this new era of particle and nuclear physics. The High Energy Frontier Our current understanding of the fundamental interactions of nature is encap- sulated in the Standard Model of particle physics. In this theory, the multitude of subatomic particles is explained in terms of just two kinds of basic building blocks: quarks, which form protons and neutrons, and leptons, including the electron and its heavier cousins. From the three basic interactions described by the Standard Model—the strong, electroweak and gravitational forces—arise much of our understanding of the world around us, from the formation of matter in the early universe, to the energy production in the Sun, and the stability of atoms and mit physics annual 2010 roland | klute ( 41 figure 1 A photograph of the interior, central molecules. -
Introduction to Supersymmetry
Introduction to Supersymmetry Pre-SUSY Summer School Corpus Christi, Texas May 15-18, 2019 Stephen P. Martin Northern Illinois University [email protected] 1 Topics: Why: Motivation for supersymmetry (SUSY) • What: SUSY Lagrangians, SUSY breaking and the Minimal • Supersymmetric Standard Model, superpartner decays Who: Sorry, not covered. • For some more details and a slightly better attempt at proper referencing: A supersymmetry primer, hep-ph/9709356, version 7, January 2016 • TASI 2011 lectures notes: two-component fermion notation and • supersymmetry, arXiv:1205.4076. If you find corrections, please do let me know! 2 Lecture 1: Motivation and Introduction to Supersymmetry Motivation: The Hierarchy Problem • Supermultiplets • Particle content of the Minimal Supersymmetric Standard Model • (MSSM) Need for “soft” breaking of supersymmetry • The Wess-Zumino Model • 3 People have cited many reasons why extensions of the Standard Model might involve supersymmetry (SUSY). Some of them are: A possible cold dark matter particle • A light Higgs boson, M = 125 GeV • h Unification of gauge couplings • Mathematical elegance, beauty • ⋆ “What does that even mean? No such thing!” – Some modern pundits ⋆ “We beg to differ.” – Einstein, Dirac, . However, for me, the single compelling reason is: The Hierarchy Problem • 4 An analogy: Coulomb self-energy correction to the electron’s mass A point-like electron would have an infinite classical electrostatic energy. Instead, suppose the electron is a solid sphere of uniform charge density and radius R. An undergraduate problem gives: 3e2 ∆ECoulomb = 20πǫ0R 2 Interpreting this as a correction ∆me = ∆ECoulomb/c to the electron mass: 15 0.86 10− meters m = m + (1 MeV/c2) × .