Chiral Dynamics of Baryons in the Perturbative Chiral Quark Model
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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. -
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. -
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 -
Quark Structure of Pseudoscalar Mesons Light Pseudoscalar Mesons Can Be Identified As (Almost) Goldstone Bosons
International Journal of Modern Physics A, c❢ World Scientific Publishing Company QUARK STRUCTURE OF PSEUDOSCALAR MESONS THORSTEN FELDMANN∗ Fachbereich Physik, Universit¨at Wuppertal, Gaußstraße 20 D-42097 Wuppertal, Germany I review to which extent the properties of pseudoscalar mesons can be understood in terms of the underlying quark (and eventually gluon) structure. Special emphasis is put on the progress in our understanding of η-η′ mixing. Process-independent mixing parameters are defined, and relations between different bases and conventions are studied. Both, the low-energy description in the framework of chiral perturbation theory and the high-energy application in terms of light-cone wave functions for partonic Fock states, are considered. A thorough discussion of theoretical and phenomenological consequences of the mixing approach will be given. Finally, I will discuss mixing with other states 0 (π , ηc, ...). 1. Introduction The fundamental degrees of freedom in strong interactions of hadronic matter are quarks and gluons, and their behavior is controlled by Quantum Chromodynamics (QCD). However, due to the confinement mechanism in QCD, in experiments the only observables are hadrons which appear as complex bound systems of quarks and gluons. A rigorous analytical solution of how to relate quarks and gluons in QCD to the hadronic world is still missing. We have therefore developed effective descriptions that allow us to derive non-trivial statements about hadronic processes from QCD and vice versa. It should be obvious that the notion of quark or gluon structure may depend on the physical context. Therefore one aim is to find process- independent concepts which allow a comparison of different approaches. -
Arxiv:1702.08417V3 [Hep-Ph] 31 Aug 2017
Strong couplings and form factors of charmed mesons in holographic QCD Alfonso Ballon-Bayona,∗ Gast~aoKrein,y and Carlisson Millerz Instituto de F´ısica Te´orica, Universidade Estadual Paulista, Rua Dr. Bento Teobaldo Ferraz, 271 - Bloco II, 01140-070 S~aoPaulo, SP, Brazil We extend the two-flavor hard-wall holographic model of Erlich, Katz, Son and Stephanov [Phys. Rev. Lett. 95, 261602 (2005)] to four flavors to incorporate strange and charm quarks. The model incorporates chiral and flavor symmetry breaking and provides a reasonable description of masses and weak decay constants of a variety of scalar, pseudoscalar, vector and axial-vector strange and charmed mesons. In particular, we examine flavor symmetry breaking in the strong couplings of the ρ meson to the charmed D and D∗ mesons. We also compute electromagnetic form factors of the π, ρ, K, K∗, D and D∗ mesons. We compare our results for the D and D∗ mesons with lattice QCD data and other nonperturbative approaches. I. INTRODUCTION are taken from SU(4) flavor and heavy-quark symmetry relations. For instance, SU(4) symmetry relates the cou- There is considerable current theoretical and exper- plings of the ρ to the pseudoscalar mesons π, K and D, imental interest in the study of the interactions of namely gρDD = gKKρ = gρππ=2. If in addition to SU(4) charmed hadrons with light hadrons and atomic nu- flavor symmetry, heavy-quark spin symmetry is invoked, clei [1{3]. There is special interest in the properties one has gρDD = gρD∗D = gρD∗D∗ = gπD∗D to leading or- of D mesons in nuclear matter [4], mainly in connec- der in the charm quark mass [27, 28]. -
Analysis of Pseudoscalar and Scalar $D$ Mesons and Charmonium
PHYSICAL REVIEW C 101, 015202 (2020) Analysis of pseudoscalar and scalar D mesons and charmonium decay width in hot magnetized asymmetric nuclear matter Rajesh Kumar* and Arvind Kumar† Department of Physics, Dr. B. R. Ambedkar National Institute of Technology Jalandhar, Jalandhar 144011 Punjab, India (Received 27 August 2019; revised manuscript received 19 November 2019; published 8 January 2020) In this paper, we calculate the mass shift and decay constant of isospin-averaged pseudoscalar (D+, D0 ) +, 0 and scalar (D0 D0 ) mesons by the magnetic-field-induced quark and gluon condensates at finite density and temperature of asymmetric nuclear matter. We have calculated the in-medium chiral condensates from the chiral SU(3) mean-field model and subsequently used these condensates in QCD sum rules to calculate the effective mass and decay constant of D mesons. Consideration of external magnetic-field effects in hot and dense nuclear matter lead to appreciable modification in the masses and decay constants of D mesons. Furthermore, we also ψ ,ψ ,χ ,χ studied the effective decay width of higher charmonium states [ (3686) (3770) c0(3414) c2(3556)] as a 3 by-product by using the P0 model, which can have an important impact on the yield of J/ψ mesons. The results of the present work will be helpful to understand the experimental observables of heavy-ion colliders which aim to produce matter at finite density and moderate temperature. DOI: 10.1103/PhysRevC.101.015202 I. INTRODUCTION debateable topic. Many theories suggest that the magnetic field produced in HICs does not die immediately due to the Future heavy-ion colliders (HIC), such as the Japan Proton interaction of itself with the medium. -
In-Medium QCD Sum Rules for Ω Meson, Nucleon and D Meson QCD-Summenregeln F ¨Ur Im Medium Modifizierte Ω-Mesonen, Nukleonen Und D-Mesonen
Institut f¨ur Theoretische Physik Fakult¨at Mathematik und Naturwissenschaften Technische Universit¨at Dresden In-Medium QCD Sum Rules for ω Meson, Nucleon and D Meson QCD-Summenregeln f ¨ur im Medium modifizierte ω-Mesonen, Nukleonen und D-Mesonen Dissertation zur Erlangung des akademischen Grades Doctor rerum naturalium vorgelegt von Ronny Thomas geboren am 7. Februar 1978 in Dresden C Dresden 2008 To Andrea and Maximilian Eingereicht am 07. Oktober 2008 1. Gutachter: Prof. Dr. Burkhard K¨ampfer 2. Gutachter: Prof. Dr. Christian Fuchs 3. Gutachter: PD Dr. Stefan Leupold Verteidigt am 28. Januar 2009 Abstract The modifications of hadronic properties caused by an ambient nuclear medium are investigated within the scope of QCD sum rules. This is exemplified for the cases of the ω meson, the nucleon and the D meson. By virtue of the sum rules, integrated spectral densities of these hadrons are linked to properties of the QCD ground state, quantified in condensates. For the cases of the ω meson and the nucleon it is discussed how the sum rules allow a restriction of the parameter range of poorly known four-quark condensates by a comparison of experimental and theoretical knowledge. The catalog of independent four-quark condensates is covered and relations among these condensates are revealed. The behavior of four-quark condensates under the chiral symmetry group and the relation to order parameters of spontaneous chiral symmetry breaking are outlined. In this respect, also the QCD condensates appearing in differences of sum rules of chiral partners are investigated. Finally, the effects of an ambient nuclear medium on the D meson are discussed and relevant condensates are identified. -
Quark Diagram Analysis of Bottom Meson Decays Emitting Pseudoscalar and Vector Mesons
Quark Diagram Analysis of Bottom Meson Decays Emitting Pseudoscalar and Vector Mesons Maninder Kaur†, Supreet Pal Singh and R. C. Verma Department of Physics, Punjabi University, Patiala – 147002, India. e-mail: [email protected], [email protected] and [email protected] Abstract This paper presents the two body weak nonleptonic decays of B mesons emitting pseudoscalar (P) and vector (V) mesons within the framework of the diagrammatic approach at flavor SU(3) symmetry level. Using the decay amplitudes, we are able to relate the branching fractions of B PV decays induced by both b c and b u transitions, which are found to be well consistent with the measured data. We also make predictions for some decays, which can be tested in future experiments. PACS No.:13.25.Hw, 11.30.Hv, 14.40.Nd †Corresponding author: [email protected] 1. Introduction At present, several groups at Fermi lab, Cornell, CERN, DESY, KEK and Beijing Electron Collider etc. are working to ensure wide knowledge of the heavy flavor physics. In future, a large quantity of new and accurate data on decays of the heavy flavor hadrons is expected which calls for their theoretical analysis. Being heavy, bottom hadrons have several channels for their decays, categorized as leptonic, semi-leptonic and hadronic decays [1-2]. The b quark is especially interesting in this respect as it has W-mediated transitions to both first generation (u) and second generation (c) quarks. Standard model provides satisfactory explanation of the leptonic and semileptonic decays but weak hadronic decays confronts serious problem as these decays experience strong interactions interferences [3-6]. -
Non-Perturbative Gluons and Pseudoscalar Mesons in Baryon Spectroscopy
View metadata, citation and similar papers at core.ac.uk brought to you by CORE Non-perturbative Gluons and Pseudoscalar Mesons in Baryonprovided by CERN Document Server Spectroscopy Z. Dziembowskia, M. Fabre de la Ripelleb, and Gerald A. Millerc a Department of Physics Temple University Philadelphia, PA 19122 b Institut de Physique Nucleaire, Universite de Paris-Sud, 94106 Orsay, France c Department of Physics University of Washington, Box 351560 Seattle, WA 98195-1560 Abstract We study baryon spectroscopy including the effects of pseudoscalar meson exchange and one gluon exchange potentials between quarks, governed by αs. The non-perturbative, hyperspherical method calculations show that one can obtain a good description of the data by using a quark-meson coupling con- stant that is compatible with the measured pion-nucleon coupling constant, and a reasonably small value of αs. Typeset using REVTEX 1 Interest in studying baryon spectroscopy has been re-vitalized by the recent work of Glozman and Riska [1–5]. These authors point out the persistent difficulty in obtaining a simultaneous description of the masses of the P-wave baryon resonances and the Roper- nucleon mass difference. In particular they argue [2] that “the spectra of the nucleons, ∆ resonances and the strange hyperons are well described by the constituent quark model, if in addition to the harmonic confinement potential the quarks are assumed to interact by exchange of the SU(3)F octet of pseudoscalar mesons”. Furthermore, Ref. [5] states that gluon exchange has no relation with the spectrum of baryons ! The ideas of Glozman and Riska are especially interesting because of the good descrip- tions of the spectra obtained in Refs. -
Inclusive Nucleon Decay Searches As a Frontier of Baryon Number Violation
UCI-TR-2019-24 Inclusive Nucleon Decay Searches as a Frontier of Baryon Number Violation Julian Heeck1, ∗ and Volodymyr Takhistov2, y 1Department of Physics and Astronomy, University of California, Irvine Irvine, California, 92697-4575, USA 2Department of Physics and Astronomy, University of California, Los Angeles Los Angeles, California, 90095-1547, USA Proton decay, and the decay of nucleons in general, constitutes one of the most sensitive probes of high-scale physics beyond the Standard Model. Most of the existing nucleon decay searches have focused primarily on two-body decay channels, motivated by Grand Unified Theories and supersymmetry. However, many higher-dimensional operators violating baryon number by one unit, ∆B = 1, induce multi-body nucleon decay channels, which have been only weakly constrained thus far. While direct searches for all such possible channels are desirable, they are highly impractical. In light of this, we argue that inclusive nucleon decay searches, N ! X+anything (where X is a light Standard Model particle with an unknown energy distribution), are particularly valuable, as are model-independent and invisible nucleon decay searches such as n ! invisible. We comment on complementarity and opportunities for such searches in the current as well as upcoming large- scale experiments Super-Kamiokande, Hyper-Kamiokande, JUNO, and DUNE. Similar arguments apply to ∆B > 1 processes, which kinematically allow for even more involved final states and are essentially unexplored experimentally. CONTENTS I. INTRODUCTION I. Introduction 1 Baryon number B and lepton number L are seem- ingly accidentally conserved in the Standard Model (SM), II. Nucleon decay operators 2 which makes searches for their violation extremely impor- A.