Mesons Beyond the Naive Quark Model
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The Positons of the Three Quarks Composing the Proton Are Illustrated
The posi1ons of the three quarks composing the proton are illustrated by the colored spheres. The surface plot illustrates the reduc1on of the vacuum ac1on density in a plane passing through the centers of the quarks. The vector field illustrates the gradient of this reduc1on. The posi1ons in space where the vacuum ac1on is maximally expelled from the interior of the proton are also illustrated by the tube-like structures, exposing the presence of flux tubes. a key point of interest is the distance at which the flux-tube formaon occurs. The animaon indicates that the transi1on to flux-tube formaon occurs when the distance of the quarks from the center of the triangle is greater than 0.5 fm. again, the diameter of the flux tubes remains approximately constant as the quarks move to large separaons. • Three quarks indicated by red, green and blue spheres (lower leb) are localized by the gluon field. • a quark-an1quark pair created from the gluon field is illustrated by the green-an1green (magenta) quark pair on the right. These quark pairs give rise to a meson cloud around the proton. hEp://www.physics.adelaide.edu.au/theory/staff/leinweber/VisualQCD/Nobel/index.html Nucl. Phys. A750, 84 (2005) 1000000 QCD mass 100000 Higgs mass 10000 1000 100 Mass (MeV) 10 1 u d s c b t GeV HOW does the rest of the proton mass arise? HOW does the rest of the proton spin (magnetic moment,…), arise? Mass from nothing Dyson-Schwinger and Lattice QCD It is known that the dynamical chiral symmetry breaking; namely, the generation of mass from nothing, does take place in QCD. -
Effects of Scalar Mesons in a Skyrme Model with Hidden Local Symmetry
Effects of scalar mesons in a Skyrme model with hidden local symmetry 1, 2, 1, Bing-Ran He, ∗ Yong-Liang Ma, † and Masayasu Harada ‡ 1Department of Physics, Nagoya University, Nagoya, 464-8602, Japan 2Center of Theoretical Physics and College of Physics, Jilin University, Changchun, 130012, China (Dated: March 5, 2018) We study the effects of light scalar mesons on the skyrmion properties by constructing and ex- amining a mesonic model including pion, rho meson, and omega meson fields as well as two-quark and four-quark scalar meson fields. In our model, the physical scalar mesons are defined as mixing states of the two- and four-quark fields. We first omit the four-quark scalar meson field from the model and find that when there is no direct coupling between the two-quark scalar meson and the vector mesons, the soliton mass is smaller and the soliton size is larger for lighter scalar mesons; when direct coupling is switched on, as the coupling strength increases, the soliton becomes heavy, and the radius of the baryon number density becomes large, as the repulsive force arising from the ω meson becomes strong. We then include the four-quark scalar meson field in the model and find that mixing between the two-quark and four-quark components of the scalar meson fields also affects the properties of the soliton. When the two-quark component of the lighter scalar meson is increased, the soliton mass decreases and the soliton size increases. PACS numbers: 11.30.Rd, 12.39.Dc, 12.39.Fe, 14.40.Be I. -
Qt7r7253zd.Pdf
Lawrence Berkeley National Laboratory Recent Work Title RELATIVISTIC QUARK MODEL BASED ON THE VENEZIANO REPRESENTATION. II. GENERAL TRAJECTORIES Permalink https://escholarship.org/uc/item/7r7253zd Author Mandelstam, Stanley. Publication Date 1969-09-02 eScholarship.org Powered by the California Digital Library University of California Submitted to Physical Review UCRL- 19327 Preprint 7. z RELATIVISTIC QUARK MODEL BASED ON THE VENEZIANO REPRESENTATION. II. GENERAL TRAJECTORIES RECEIVED LAWRENCE RADIATION LABORATORY Stanley Mandeistam SEP25 1969 September 2, 1969 LIBRARY AND DOCUMENTS SECTiON AEC Contract No. W7405-eng-48 TWO-WEEK LOAN COPY 4 This is a Library Circulating Copy whIch may be borrowed for two weeks. for a personal retention copy, call Tech. Info. Dlvislon, Ext. 5545 I C.) LAWRENCE RADIATION LABORATOR SLJ-LJ UNIVERSITY of CALIFORNIA BERKELET 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. -
Hadrons and Nuclei Abstract
Hadrons and Nuclei William Detmold (editor),1 Robert G. Edwards (editor),2 Jozef J. Dudek,2, 3 Michael Engelhardt,4 Huey-Wen Lin,5 Stefan Meinel,6, 7 Kostas Orginos,2, 3 and Phiala Shanahan1 (USQCD Collaboration) 1Massachusetts Institute of Technology 2Jefferson Lab 3College of William and Mary 4New Mexico State University 5Michigan State University 6University of Arizona 7RIKEN BNL Research Center Abstract This document is one of a series of whitepapers from the USQCD collaboration. Here, we discuss opportunities for lattice QCD calculations related to the structure and spectroscopy of hadrons and nuclei. An overview of recent lattice calculations of the structure of the proton and other hadrons is presented along with prospects for future extensions. Progress and prospects of hadronic spectroscopy and the study of resonances in the light, strange and heavy quark sectors is summarized. Finally, recent advances in the study of light nuclei from lattice QCD are addressed, and the scope of future investigations that are currently envisioned is outlined. 1 CONTENTS Executive summary3 I. Introduction3 II. Hadron Structure4 A. Charges, radii, electroweak form factors and polarizabilities4 B. Parton Distribution Functions5 1. Moments of Parton Distribution Functions6 2. Quasi-distributions and pseudo-distributions6 3. Good lattice cross sections7 4. Hadronic tensor methods8 C. Generalized Parton Distribution Functions8 D. Transverse momentum-dependent parton distributions9 E. Gluon aspects of hadron structure 11 III. Hadron Spectroscopy 13 A. Light hadron spectroscopy 14 B. Heavy quarks and the XYZ states 20 IV. Nuclear Spectroscopy, Interactions and Structure 21 A. Nuclear spectroscopy 22 B. Nuclear Structure 23 C. Nuclear interactions 26 D. -
First Determination of the Electric Charge of the Top Quark
First Determination of the Electric Charge of the Top Quark PER HANSSON arXiv:hep-ex/0702004v1 1 Feb 2007 Licentiate Thesis Stockholm, Sweden 2006 Licentiate Thesis First Determination of the Electric Charge of the Top Quark Per Hansson Particle and Astroparticle Physics, Department of Physics Royal Institute of Technology, SE-106 91 Stockholm, Sweden Stockholm, Sweden 2006 Cover illustration: View of a top quark pair event with an electron and four jets in the final state. Image by DØ Collaboration. Akademisk avhandling som med tillst˚and av Kungliga Tekniska H¨ogskolan i Stock- holm framl¨agges till offentlig granskning f¨or avl¨aggande av filosofie licentiatexamen fredagen den 24 november 2006 14.00 i sal FB54, AlbaNova Universitets Center, KTH Partikel- och Astropartikelfysik, Roslagstullsbacken 21, Stockholm. Avhandlingen f¨orsvaras p˚aengelska. ISBN 91-7178-493-4 TRITA-FYS 2006:69 ISSN 0280-316X ISRN KTH/FYS/--06:69--SE c Per Hansson, Oct 2006 Printed by Universitetsservice US AB 2006 Abstract In this thesis, the first determination of the electric charge of the top quark is presented using 370 pb−1 of data recorded by the DØ detector at the Fermilab Tevatron accelerator. tt¯ events are selected with one isolated electron or muon and at least four jets out of which two are b-tagged by reconstruction of a secondary decay vertex (SVT). The method is based on the discrimination between b- and ¯b-quark jets using a jet charge algorithm applied to SVT-tagged jets. A method to calibrate the jet charge algorithm with data is developed. A constrained kinematic fit is performed to associate the W bosons to the correct b-quark jets in the event and extract the top quark electric charge. -
1– N and ∆ RESONANCES Revised May 2015 by V. Burkert
– 1– N AND ∆ RESONANCES Revised May 2015 by V. Burkert (Jefferson Lab), E. Klempt (University of Bonn), M.R. Pennington (Jefferson Lab), L. Tiator (University of Mainz), and R.L. Workman (George Washington University). I. Introduction The excited states of the nucleon have been studied in a large number of formation and production experiments. The Breit-Wigner masses and widths, the pole positions, and the elasticities of the N and ∆ resonances in the Baryon Summary Table come largely from partial-wave analyses of πN total, elastic, and charge-exchange scattering data. The most com- prehensive analyses were carried out by the Karlsruhe-Helsinki (KH80) [1], Carnegie Mellon-Berkeley (CMB80) [2], and George Washington U (GWU) [3] groups. Partial-wave anal- yses have also been performed on much smaller πN reaction data sets to get ηN, KΛ, and KΣ branching fractions (see the Listings for references). Other branching fractions come from analyses of πN ππN data. → In recent years, a large amount of data on photoproduction of many final states has been accumulated, and these data are beginning to tell us much about the properties of baryon resonances. A survey of data on photoproduction can be found in the proceedings of recent conferences [4] and workshops [5], and in recent reviews [6,7]. II. Naming scheme for baryon resonances In the past, when nearly all resonance information came from elastic πN scattering, it was common to label reso- nances with the incoming partial wave L2I,2J , as in ∆(1232)P33 and N(1680)F15. However, most recent information has come from γN experiments. -
Recent Progress on Dense Nuclear Matter in Skyrmion Approaches Yong-Liang Ma, Mannque Rho
Recent progress on dense nuclear matter in skyrmion approaches Yong-Liang Ma, Mannque Rho To cite this version: Yong-Liang Ma, Mannque Rho. Recent progress on dense nuclear matter in skyrmion approaches. SCIENCE CHINA Physics, Mechanics & Astronomy, 2017, 60, pp.032001. 10.1007/s11433-016-0497- 2. cea-01491871 HAL Id: cea-01491871 https://hal-cea.archives-ouvertes.fr/cea-01491871 Submitted on 17 Mar 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. SCIENCE CHINA Physics, Mechanics & Astronomy . Invited Review . Month 2016 Vol. *** No. ***: ****** doi: ******** Recent progress on dense nuclear matter in skyrmion approaches Yong-Liang Ma1 & Mannque Rho2 1Center of Theoretical Physics and College of Physics, Jilin University, Changchun, 130012, China; Email:[email protected] 2Institut de Physique Th´eorique, CEA Saclay, 91191 Gif-sur-Yvette c´edex, France; Email:[email protected] The Skyrme model provides a novel unified approach to nuclear physics. In this approach, single baryon, baryonic matter and medium-modified hadron properties are treated on the same footing. Intrinsic density dependence (IDD) reflecting the change of vacuum by compressed baryonic matter figures naturally in the approach. In this article, we review the recent progress on accessing dense nuclear matter by putting baryons treated as solitons, namely, skyrmions, on crystal lattice with accents on the implications in compact stars. -
Properties of Baryons in the Chiral Quark Model
Properties of Baryons in the Chiral Quark Model Tommy Ohlsson Teknologie licentiatavhandling Kungliga Tekniska Hogskolan¨ Stockholm 1997 Properties of Baryons in the Chiral Quark Model Tommy Ohlsson Licentiate Dissertation Theoretical Physics Department of Physics Royal Institute of Technology Stockholm, Sweden 1997 Typeset in LATEX Akademisk avhandling f¨or teknologie licentiatexamen (TeknL) inom ¨amnesomr˚adet teoretisk fysik. Scientific thesis for the degree of Licentiate of Engineering (Lic Eng) in the subject area of Theoretical Physics. TRITA-FYS-8026 ISSN 0280-316X ISRN KTH/FYS/TEO/R--97/9--SE ISBN 91-7170-211-3 c Tommy Ohlsson 1997 Printed in Sweden by KTH H¨ogskoletryckeriet, Stockholm 1997 Properties of Baryons in the Chiral Quark Model Tommy Ohlsson Teoretisk fysik, Institutionen f¨or fysik, Kungliga Tekniska H¨ogskolan SE-100 44 Stockholm SWEDEN E-mail: [email protected] Abstract In this thesis, several properties of baryons are studied using the chiral quark model. The chiral quark model is a theory which can be used to describe low energy phenomena of baryons. In Paper 1, the chiral quark model is studied using wave functions with configuration mixing. This study is motivated by the fact that the chiral quark model cannot otherwise break the Coleman–Glashow sum-rule for the magnetic moments of the octet baryons, which is experimentally broken by about ten standard deviations. Configuration mixing with quark-diquark components is also able to reproduce the octet baryon magnetic moments very accurately. In Paper 2, the chiral quark model is used to calculate the decuplet baryon ++ magnetic moments. The values for the magnetic moments of the ∆ and Ω− are in good agreement with the experimental results. -
Mass Shift of Σ-Meson in Nuclear Matter
Mass shift of σ-Meson in Nuclear Matter J. R. Morones-Ibarra, Mónica Menchaca Maciel, Ayax Santos-Guevara, and Felipe Robledo Padilla. Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Nuevo León, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León, 66450, México. Facultad de Ingeniería y Arquitectura, Universidad Regiomontana, 15 de Mayo 567, Monterrey, N.L., 64000, México. April 6, 2010 Abstract The propagation of sigma meson in nuclear matter is studied in the Walecka model, assuming that the sigma couples to a pair of nucleon-antinucleon states and to particle-hole states, including the in medium effect of sigma-omega mixing. We have also considered, by completeness, the coupling of sigma to two virtual pions. We have found that the sigma meson mass decreases respect to its value in vacuum and that the contribution of the sigma omega mixing effect on the mass shift is relatively small. Keywords: scalar mesons, hadrons in dense matter, spectral function, dense nuclear matter. PACS:14.40;14.40Cs;13.75.Lb;21.65.+f 1. INTRODUCTION The study of matter under extreme conditions of density and temperature, has become a very important issue due to the fact that it prepares to understand the physics for some interesting subjects like, the conditions in the early universe, the physics of processes in stellar evolution and in heavy ion collision. Particularly, the study of properties of mesons in hot and dense matter is important to understand which could be the signature for detecting the Quark-Gluon Plasma (QGP) state in heavy ion collision, and to get information about the signal of the presence of QGP and also to know which symmetries are restored [1]. -
Phenomenology of Gev-Scale Heavy Neutral Leptons Arxiv:1805.08567
Prepared for submission to JHEP INR-TH-2018-014 Phenomenology of GeV-scale Heavy Neutral Leptons Kyrylo Bondarenko,1 Alexey Boyarsky,1 Dmitry Gorbunov,2;3 Oleg Ruchayskiy4 1Intituut-Lorentz, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands 2Institute for Nuclear Research of the Russian Academy of Sciences, Moscow 117312, Russia 3Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia 4Discovery Center, Niels Bohr Institute, Copenhagen University, Blegdamsvej 17, DK- 2100 Copenhagen, Denmark E-mail: [email protected], [email protected], [email protected], [email protected] Abstract: We review and revise phenomenology of the GeV-scale heavy neutral leptons (HNLs). We extend the previous analyses by including more channels of HNLs production and decay and provide with more refined treatment, including QCD corrections for the HNLs of masses (1) GeV. We summarize the relevance O of individual production and decay channels for different masses, resolving a few discrepancies in the literature. Our final results are directly suitable for sensitivity studies of particle physics experiments (ranging from proton beam-dump to the LHC) aiming at searches for heavy neutral leptons. arXiv:1805.08567v3 [hep-ph] 9 Nov 2018 ArXiv ePrint: 1805.08567 Contents 1 Introduction: heavy neutral leptons1 1.1 General introduction to heavy neutral leptons2 2 HNL production in proton fixed target experiments3 2.1 Production from hadrons3 2.1.1 Production from light unflavored and strange mesons5 2.1.2 -
Chiral Extrapolations and Exotic Meson Spectrum
Physics Letters B 526 (2002) 72–78 www.elsevier.com/locate/npe Chiral extrapolations and exotic meson spectrum Anthony W. Thomas a, Adam P. Szczepaniak b a Special Research Centre for the Subatomic Structure of Matter and Department of Physics and Mathematical Physics, Adelaide University, Adelaide SA 5005, Australia b Department of Physics and Nuclear Theory Center, Indiana University, Bloomington, IN 47405, USA Received 15 June 2001; received in revised form 10 December 2001; accepted 18 December 2001 Editor: H. Georgi Abstract We examine the chiral corrections to exotic meson masses calculated in lattice QCD. In the soft pion limit we find that corrections from virtual, closed channels lead to strong non-linear behavior which has been found in other hadronic systems. We find the resulting mass shifts to be as large as 100 MeV and therefore large corrections to the predictions of exotic meson masses based on linear extrapolations to the chiral limit are expected. Furthermore, by considering a class of phenomenologically successful hybrid meson models we show that this behavior is not altered by contributions from open decay channels. 2002 Published by Elsevier Science B.V. One of the biggest challenges in hadronic physics is with glueballs—they have regular quantum numbers to understand the role of gluonic degrees of freedom. and therefore cannot be unambiguously identified as Even though there is evidence from high energy purely gluonic excitations. On the other hand, the ex- experiments that gluons contribute significantly to istence of mesons with exotic quantum numbers (com- hadron structure, for example, to the momentum and binations of spin, parity and charge conjugation, J PC, spin sum rules, there is a pressing need for direct which cannot be attributed to valence quarks alone), observation of gluonic excitations at low energies. -
A Quark-Meson Coupling Model for Nuclear and Neutron Matter
Adelaide University ADPT February A quarkmeson coupling mo del for nuclear and neutron matter K Saito Physics Division Tohoku College of Pharmacy Sendai Japan and y A W Thomas Department of Physics and Mathematical Physics University of Adelaide South Australia Australia March Abstract nucl-th/9403015 18 Mar 1994 An explicit quark mo del based on a mean eld description of nonoverlapping nucleon bags b ound by the selfconsistent exchange of ! and mesons is used to investigate the prop erties of b oth nuclear and neutron matter We establish a clear understanding of the relationship b etween this mo del which incorp orates the internal structure of the nucleon and QHD Finally we use the mo del to study the density dep endence of the quark condensate inmedium Corresp ondence to Dr K Saito email ksaitonuclphystohokuacjp y email athomasphysicsadelaideeduau Recently there has b een considerable interest in relativistic calculations of innite nuclear matter as well as dense neutron matter A relativistic treatment is of course essential if one aims to deal with the prop erties of dense matter including the equation of state EOS The simplest relativistic mo del for hadronic matter is the Walecka mo del often called Quantum Hadro dynamics ie QHDI which consists of structureless nucleons interacting through the exchange of the meson and the time comp onent of the meson in the meaneld approximation MFA Later Serot and Walecka extended the mo del to incorp orate the isovector mesons and QHDI I and used it to discuss systems like