[Phi] Production and the OZI Rule in [Greek Letter Pi Superscript +]D Interactions at 10 Gev/C Joel Stephen Hendrickson Iowa State University
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Selfconsistent Description of Vector-Mesons in Matter 1
Selfconsistent description of vector-mesons in matter 1 Felix Riek 2 and J¨orn Knoll 3 Gesellschaft f¨ur Schwerionenforschung Planckstr. 1 64291 Darmstadt Abstract We study the influence of the virtual pion cloud in nuclear matter at finite den- sities and temperatures on the structure of the ρ- and ω-mesons. The in-matter spectral function of the pion is obtained within a selfconsistent scheme of coupled Dyson equations where the coupling to the nucleon and the ∆(1232)-isobar reso- nance is taken into account. The selfenergies are determined using a two-particle irreducible (2PI) truncation scheme (Φ-derivable approximation) supplemented by Migdal’s short range correlations for the particle-hole excitations. The so obtained spectral function of the pion is then used to calculate the in-medium changes of the vector-meson spectral functions. With increasing density and temperature a strong interplay of both vector-meson modes is observed. The four-transversality of the polarisation tensors of the vector-mesons is achieved by a projector technique. The resulting spectral functions of both vector-mesons and, through vector domi- nance, the implications of our results on the dilepton spectra are studied in their dependence on density and temperature. Key words: rho–meson, omega–meson, medium modifications, dilepton production, self-consistent approximation schemes. PACS: 14.40.-n 1 Supported in part by the Helmholz Association under Grant No. VH-VI-041 2 e-mail:[email protected] 3 e-mail:[email protected] Preprint submitted to Elsevier Preprint Feb. 2004 1 Introduction It is an interesting question how the behaviour of hadrons changes in a dense hadronic medium. -
X. Charge Conjugation and Parity in Weak Interactions →
Charge conjugation and parity in weak interactions Particle Physics X. Charge conjugation and parity in weak interactions REMINDER: Parity The parity transformation is the transformation by reflection: → xi x'i = –xi A parity operator Pˆ is defined as Pˆ ψ()()xt, = pψ()–x, t where p = +1 Charge conjugation The charge conjugation replaces particles by their antiparticles, reversing charges and magnetic moments ˆ Ψ Ψ C a = c a where c = +1 meaning that from the particle in the initial state we go to the antiparticle in the final state. Oxana Smirnova & Vincent Hedberg Lund University 248 Charge conjugation and parity in weak interactions Particle Physics Reminder Symmetries Continuous Lorentz transformation Space-time Translation in space Symmetries Translation in time Rotation around an axis Continuous transformations that can Space-time be regarded as a series of infinitely small steps. symmetries Discrete Parity Transformations that affects the Space-time Charge conjugation space-- and time coordinates i.e. transformation of the 4-vector Symmetries Time reversal Minkowski space. Discrete transformations have only two elements i.e. two transformations. Baryon number Global Lepton number symmetries Strangeness number Isospin SU(2)flavour Internal The transformation does not depend on Isospin+Hypercharge SU(3)flavour symmetries r i.e. it is the same everywhere in space. Transformations that do not affect the space- and time- Local gauge Electric charge U(1) coordinates. symmetries Weak charge+weak isospin U(1)xSU(2) Colour SU(3) The -
J. Stroth Asked the Question: "Which Are the Experimental Evidences for a Long Mean Free Path of Phi Mesons in Medium?"
J. Stroth asked the question: "Which are the experimental evidences for a long mean free path of phi mesons in medium?" Answer by H. Stroebele ~~~~~~~~~~~~~~~~~~~ (based on the study of several publications on phi production and information provided by the theory friends of H. Stöcker ) Before trying to find an answer to this question, we need to specify what is meant with "long". The in medium cross section is equivalent to the mean free path. Thus we need to find out whether the (in medium) cross section is large (with respect to what?). The reference would be the cross sections of other mesons like pions or more specifically the omega meson. There is a further reference, namely the suppression of phi production and decay described in the OZI rule. A “blind” application of the OZI rule would give a cross section of the phi three orders of magnitude lower than that of the omega meson and correspondingly a "long" free mean path. In the following we shall look at the phi production cross sections in photon+p, pion+p, and p+p interactions. The total photoproduction cross sections of phi and omega mesons were measured in a bubble chamber experiment (J. Ballam et al., Phys. Rev. D 7, 3150, 1973), in which a cross section ratio of R(omega/phi) = 10 was found in the few GeV beam energy region. There are results on omega and phi production in p+p interactions available from SPESIII (Near- Threshold Production of omega mesons in the Reaction p p → p p omega", Phys.Rev.Lett. -
Three Lectures on Meson Mixing and CKM Phenomenology
Three Lectures on Meson Mixing and CKM phenomenology Ulrich Nierste Institut f¨ur Theoretische Teilchenphysik Universit¨at Karlsruhe Karlsruhe Institute of Technology, D-76128 Karlsruhe, Germany I give an introduction to the theory of meson-antimeson mixing, aiming at students who plan to work at a flavour physics experiment or intend to do associated theoretical studies. I derive the formulae for the time evolution of a neutral meson system and show how the mass and width differences among the neutral meson eigenstates and the CP phase in mixing are calculated in the Standard Model. Special emphasis is laid on CP violation, which is covered in detail for K−K mixing, Bd−Bd mixing and Bs−Bs mixing. I explain the constraints on the apex (ρ, η) of the unitarity triangle implied by ǫK ,∆MBd ,∆MBd /∆MBs and various mixing-induced CP asymmetries such as aCP(Bd → J/ψKshort)(t). The impact of a future measurement of CP violation in flavour-specific Bd decays is also shown. 1 First lecture: A big-brush picture 1.1 Mesons, quarks and box diagrams The neutral K, D, Bd and Bs mesons are the only hadrons which mix with their antiparticles. These meson states are flavour eigenstates and the corresponding antimesons K, D, Bd and Bs have opposite flavour quantum numbers: K sd, D cu, B bd, B bs, ∼ ∼ d ∼ s ∼ K sd, D cu, B bd, B bs, (1) ∼ ∼ d ∼ s ∼ Here for example “Bs bs” means that the Bs meson has the same flavour quantum numbers as the quark pair (b,s), i.e.∼ the beauty and strangeness quantum numbers are B = 1 and S = 1, respectively. -
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]. -
Understanding the J/Psi Production Mechanism at PHENIX Todd Kempel Iowa State University
Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2010 Understanding the J/psi Production Mechanism at PHENIX Todd Kempel Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Physics Commons Recommended Citation Kempel, Todd, "Understanding the J/psi Production Mechanism at PHENIX" (2010). Graduate Theses and Dissertations. 11649. https://lib.dr.iastate.edu/etd/11649 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Understanding the J= Production Mechanism at PHENIX by Todd Kempel A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Nuclear Physics Program of Study Committee: John G. Lajoie, Major Professor Kevin L De Laplante S¨orenA. Prell J¨orgSchmalian Kirill Tuchin Iowa State University Ames, Iowa 2010 Copyright c Todd Kempel, 2010. All rights reserved. ii TABLE OF CONTENTS LIST OF TABLES . v LIST OF FIGURES . vii CHAPTER 1. Overview . 1 CHAPTER 2. Quantum Chromodynamics . 3 2.1 The Standard Model . 3 2.2 Quarks and Gluons . 5 2.3 Asymptotic Freedom and Confinement . 6 CHAPTER 3. The Proton . 8 3.1 Cross-Sections and Luminosities . 8 3.2 Deep-Inelastic Scattering . 10 3.3 Structure Functions and Bjorken Scaling . 12 3.4 Altarelli-Parisi Evolution . -
Charge Conjugation Symmetry
Charge Conjugation Symmetry In the previous set of notes we followed Dirac's original construction of positrons as holes in the electron's Dirac sea. But the modern point of view is rather different: The Dirac sea is experimentally undetectable | it's simply one of the aspects of the physical ? vacuum state | and the electrons and the positrons are simply two related particle species. Moreover, the electrons and the positrons have exactly the same mass but opposite electric charges. Many other particle species exist in similar particle-antiparticle pairs. The particle and the corresponding antiparticle have exactly the same mass but opposite electric charges, as well as other conserved charges such as the lepton number or the baryon number. Moreover, the strong and the electromagnetic interactions | but not the weak interactions | respect the change conjugation symmetry which turns particles into antiparticles and vice verse, C^ jparticle(p; s)i = jantiparticle(p; s)i ; C^ jantiparticle(p; s)i = jparticle(p; s)i ; (1) − + + − for example C^ e (p; s) = e (p; s) and C^ e (p; s) = e (p; s) . In light of this sym- metry, deciding which particle species is particle and which is antiparticle is a matter of convention. For example, we know that the charged pions π+ and π− are each other's an- tiparticles, but it's up to our choice whether we call the π+ mesons particles and the π− mesons antiparticles or the other way around. In the Hilbert space of the quantum field theory, the charge conjugation operator C^ is a unitary operator which squares to 1, thus C^ 2 = 1 =) C^ y = C^ −1 = C^:; (2) ? In condensed matter | say, in a piece of semiconductor | we may detect the filled electron states by making them interact with the outside world. -
Kaon to Two Pions Decays from Lattice QCD: ∆I = 1/2 Rule and CP
Kaon to Two Pions decays from Lattice QCD: ∆I =1/2 rule and CP violation Qi Liu Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2012 c 2012 Qi Liu All Rights Reserved Abstract Kaon to Two Pions decays from Lattice QCD: ∆I =1/2 rule and CP violation Qi Liu We report a direct lattice calculation of the K to ππ decay matrix elements for both the ∆I = 1/2 and 3/2 amplitudes A0 and A2 on a 2+1 flavor, domain wall fermion, 163 32 16 lattice ensemble and a 243 64 16 lattice ensemble. This × × × × is a complete calculation in which all contractions for the required ten, four-quark operators are evaluated, including the disconnected graphs in which no quark line connects the initial kaon and final two-pion states. These lattice operators are non- perturbatively renormalized using the Rome-Southampton method and the quadratic divergences are studied and removed. This is an important but notoriously difficult calculation, requiring high statistics on a large volume. In this work we take a major step towards the computation of the physical K ππ amplitudes by performing → a complete calculation at unphysical kinematics with pions of mass 422MeV and 329MeV at rest in the kaon rest frame. With this simplification we are able to 3 resolve Re(A0) from zero for the first time, with a 25% statistical error on the 16 3 lattice and 15% on the 24 lattice. The complex amplitude A2 is calculated with small statistical errors. -
And G-Parity: a New Definition and Applications —Version Viib—
BNL PREPRINT BNL-QGS-13-0901 Cparity7b.tex C- and G-parity: A New Definition and Applications |Version VIIb| S. U. Chung α Physics Department Brookhaven National Laboratory, Upton, NY 11973, U.S.A. β Department of Physics Pusan National University, Busan 609-735, Republic of Korea γ and Excellence Cluster Universe Physik Department E18, Technische Universit¨atM¨unchen,Germany δ September 29, 2013 abstract A new definition for C (charge-conjugation) and G operations is proposed which allows for unique value of the C parity for each member of a given J PC nonet. A simple straightforward extension of the definition allows quarks to be treated on an equal footing. As illustrative examples, the problems of constructing eigenstates of C, I and G operators are worked out for ππ, KK¯ , NN¯ and qq¯ systems. In particular, a thorough treatment of two-, three- and four-body systems involving KK¯ systems is given. α CERN Visiting Scientist (part time) β Senior Scientist Emeritus γ Research Professor (part time) δ Scientific Consultant (part time) 1 Introduction The purpose of this note is to point out that the C operation can be defined in such a way that a unique value can be assigned to all the members of a given J PC nonet. In conventional treatments in which antiparticle states are defined through C, one encounters the problem that anti-particle states do not transform in the same way (the so-called charge-conjugate representation). That this is so is obvious if one considers the fact that a C operation changes sign of the z-component of the I-spin, so that in general C and I operators do not commute. -
Arxiv:1706.02588V2 [Hep-Ph] 29 Apr 2019 D D O Oeua Tts Ntehde Hr Etrw Have We Sector Candidates Charm Good Hidden the Particularly the in As Are States
Heavy Baryon-Antibaryon Molecules in Effective Field Theory 1, 2 1, 1, Jun-Xu Lu, Li-Sheng Geng, ∗ and Manuel Pavon Valderrama † 1School of Physics and Nuclear Energy Engineering, International Research Center for Nuclei and Particles in the Cosmos and Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing 100191, China 2Institut de Physique Nucl´eaire, CNRS-IN2P3, Univ. Paris-Sud, Universit´eParis-Saclay, F-91406 Orsay Cedex, France (Dated: April 30, 2019) We discuss the effective field theory description of bound states composed of a heavy baryon and antibaryon. This framework is a variation of the ones already developed for heavy meson- antimeson states to describe the X(3872) or the Zc and Zb resonances. We consider the case of heavy baryons for which the light quark pair is in S-wave and we explore how heavy quark spin symmetry constrains the heavy baryon-antibaryon potential. The one pion exchange potential mediates the low energy dynamics of this system. We determine the relative importance of pion exchanges, in particular the tensor force. We find that in general pion exchanges are probably non- ¯ ¯ ¯ ¯ ¯ ¯ perturbative for the ΣQΣQ, ΣQ∗ ΣQ and ΣQ∗ ΣQ∗ systems, while for the ΞQ′ ΞQ′ , ΞQ∗ ΞQ′ and ΞQ∗ ΞQ∗ cases they are perturbative. If we assume that the contact-range couplings of the effective field theory are saturated by the exchange of vector mesons, we can estimate for which quantum numbers it is more probable to find a heavy baryonium state. The most probable candidates to form bound states are ¯ ¯ ¯ ¯ ¯ ¯ the isoscalar ΛQΛQ, ΣQΣQ, ΣQ∗ ΣQ and ΣQ∗ ΣQ∗ and the isovector ΛQΣQ and ΛQΣQ∗ systems, both in the hidden-charm and hidden-bottom sectors. -
Kaon Pair Production in Pp, Pd, Dd and Pa Collisions at COSY
Kaon pair production in pp, pd, dd and pA collisions at COSY Michael Hartmann Institut für Kernphysik and Jülich Centre for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich, Germany E-mail: [email protected] An overview of experiments at the Cooler Synchrotron COSY on kaon-pair production in pp, pd, dd collisions in the close-to-threshold regime is given. These include results on f-meson production, where the meson is detected via its K+K− decay. The study of f production on a range of heavier nuclear targets allows one to deduce a value of the f width in nuclei and its variation with the f momentum. XLIX International Winter Meeting on Nuclear Physics, BORMIO2011 January 24-28, 2011 Bormio, Italy c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ Kaon pair production at COSY 1. Introduction The cooler synchrotron COSY [1] at the Forschungszentrum Jülich in Germany can accelerate protons and deuterons up to about 3.7 GeV/c. Both polarized and unpolarized beams are available. Excellent beam quality is achieved with the help of electron and/or stochastic cooling. COSY can be used as an accelerator for external target experiments and as a storage ring for internal target experiments. Kaon pair production experiments have been performed at the internal spectrometer ANKE by the COSY-ANKE collaboration, at the internal COSY-11 spectrometer by the COSY-11 collaboration, and at the external BIG KARL spectrograph by the COSY-MOMO collaboration. 103 102 10 pn → dφ total corss section [nb] pp → ppφ 1 pp → ppφ pd → 3Heφ pn → dK+K pp → ppK+K 1 10 pp → ppK+K pp → ppK+K o pp → dK+K pd → 3HeK+K 2 10 dd → 4HeK+K 0 20 40 60 80 100 Excess energy [MeV] Figure 1: World data set on total cross sections for kaon-pair production in terms of the excess energy for each reaction. -
Researcher 2015;7(8)
Researcher 2015;7(8) http://www.sciencepub.net/researcher Curie Particle And The Relation Between The Masses Of Sub-Atomic Particles, Supporting (Bicep2`S) Experiments, Mass Of Neutrino, Present “The Lhcb Collaboration” & “Atlas” Experiments. Nirmalendu Das Life Member (1): THE VON KARMAN SOCIETY for Advanced Study and Research in Mathematical Science (UKS), Old Post Office line, Jalpaiguri, Life Member (2): Indian Science Congress Association, India. Resident Address: MUKUL DEEP, Saratpally, W.No.- 40, 74/48, Meghlal Roy Road Haiderpara, Siliguri – 734006, Dist: Jalpaiguri, West Bengal, India. Mob: +91-9475089337, Email: [email protected], [email protected] Abstract: Light is very sensitive matter. In terms of mass of a photon is important in every field of matter thus for the universe. The scientists of many countries are trying to find the mass of photon by experiment since 1936 and continuing this work in various countries. But the obtained results are differing to each other. So, we cannot consider these mass of a photon. On the other hand matter is made by the photons. We get this idea from the Einstein equation E = mc2. Again, energy is nothing but the bunch of photons. I calculate the mass of a photon (1.6596x10-54 gm) [1] and this mass is applicable to all fields. Here, in this article, we can calculate the mass of “Curie particle” (Unknown to us) by using this mass of photon & is related to Higgs and other sub-atomic particles. The energy of Higgs particle is very low as per BICEP2`s experimental report [2] and I reported about this matter in the year 2011 to “The Authority of CERN, Editor of Press release of CERN and many other places” by emailing, but did not get answer in this regards.