Charm Meson Molecules and the X(3872)
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
The Particle World
The Particle World ² What is our Universe made of? This talk: ² Where does it come from? ² particles as we understand them now ² Why does it behave the way it does? (the Standard Model) Particle physics tries to answer these ² prepare you for the exercise questions. Later: future of particle physics. JMF Southampton Masterclass 22–23 Mar 2004 1/26 Beginning of the 20th century: atoms have a nucleus and a surrounding cloud of electrons. The electrons are responsible for almost all behaviour of matter: ² emission of light ² electricity and magnetism ² electronics ² chemistry ² mechanical properties . technology. JMF Southampton Masterclass 22–23 Mar 2004 2/26 Nucleus at the centre of the atom: tiny Subsequently, particle physicists have yet contains almost all the mass of the discovered four more types of quark, two atom. Yet, it’s composite, made up of more pairs of heavier copies of the up protons and neutrons (or nucleons). and down: Open up a nucleon . it contains ² c or charm quark, charge +2=3 quarks. ² s or strange quark, charge ¡1=3 Normal matter can be understood with ² t or top quark, charge +2=3 just two types of quark. ² b or bottom quark, charge ¡1=3 ² + u or up quark, charge 2=3 Existed only in the early stages of the ² ¡ d or down quark, charge 1=3 universe and nowadays created in high energy physics experiments. JMF Southampton Masterclass 22–23 Mar 2004 3/26 But this is not all. The electron has a friend the electron-neutrino, ºe. Needed to ensure energy and momentum are conserved in ¯-decay: ¡ n ! p + e + º¯e Neutrino: no electric charge, (almost) no mass, hardly interacts at all. -
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. -
Qcd in Heavy Quark Production and Decay
QCD IN HEAVY QUARK PRODUCTION AND DECAY Jim Wiss* University of Illinois Urbana, IL 61801 ABSTRACT I discuss how QCD is used to understand the physics of heavy quark production and decay dynamics. My discussion of production dynam- ics primarily concentrates on charm photoproduction data which is compared to perturbative QCD calculations which incorporate frag- mentation effects. We begin our discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay is then reviewed. Mea- surements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge The- ories. We next discuss polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daugh- ter baryon will recoil from the charmed parent with nearly 100% left- handed polarization, which is in excellent agreement with present data. We conclude by discussing nonleptonic charm decay which are tradi- tionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as mod- ifying the interference between Interfering resonance channels which contribute to specific multibody decays. "Supported by DOE Contract DE-FG0201ER40677. © 1996 by Jim Wiss. -251- 1 Introduction the direction of fixed-target experiments. Perhaps they serve as a sort of swan song since the future of fixed-target charm experiments in the United States is A vast amount of important data on heavy quark production and decay exists for very short. -
Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays
Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays !Resonances !Heavy Meson and Baryons !Decays and Quantum numbers !CKM matrix 1 Announcements •No lecture on Friday. •Remaining lectures: •Tuesday 13 March •Friday 16 March •Tuesday 20 March •Friday 23 March •Tuesday 27 March •Friday 30 March •Tuesday 3 April •Remaining Tutorials: •Monday 26 March •Monday 2 April 2 From Friday: Mesons and Baryons Summary • Quarks are confined to colourless bound states, collectively known as hadrons: " mesons: quark and anti-quark. Bosons (s=0, 1) with a symmetric colour wavefunction. " baryons: three quarks. Fermions (s=1/2, 3/2) with antisymmetric colour wavefunction. " anti-baryons: three anti-quarks. • Lightest mesons & baryons described by isospin (I, I3), strangeness (S) and hypercharge Y " isospin I=! for u and d quarks; (isospin combined as for spin) " I3=+! (isospin up) for up quarks; I3="! (isospin down) for down quarks " S=+1 for strange quarks (additive quantum number) " hypercharge Y = S + B • Hadrons display SU(3) flavour symmetry between u d and s quarks. Used to predict the allowed meson and baryon states. • As baryons are fermions, the overall wavefunction must be anti-symmetric. The wavefunction is product of colour, flavour, spin and spatial parts: ! = "c "f "S "L an odd number of these must be anti-symmetric. • consequences: no uuu, ddd or sss baryons with total spin J=# (S=#, L=0) • Residual strong force interactions between colourless hadrons propagated by mesons. 3 Resonances • Hadrons which decay due to the strong force have very short lifetime # ~ 10"24 s • Evidence for the existence of these states are resonances in the experimental data Γ2/4 σ = σ • Shape is Breit-Wigner distribution: max (E M)2 + Γ2/4 14 41. -
Arxiv:1502.07763V2 [Hep-Ph] 1 Apr 2015
Constraints on Dark Photon from Neutrino-Electron Scattering Experiments S. Bilmi¸s,1 I. Turan,1 T.M. Aliev,1 M. Deniz,2, 3 L. Singh,2, 4 and H.T. Wong2 1Department of Physics, Middle East Technical University, Ankara 06531, Turkey. 2Institute of Physics, Academia Sinica, Taipei 11529, Taiwan. 3Department of Physics, Dokuz Eyl¨ulUniversity, Izmir,_ Turkey. 4Department of Physics, Banaras Hindu University, Varanasi, 221005, India. (Dated: April 2, 2015) Abstract A possible manifestation of an additional light gauge boson A0, named as Dark Photon, associated with a group U(1)B−L is studied in neutrino electron scattering experiments. The exclusion plot on the coupling constant gB−L and the dark photon mass MA0 is obtained. It is shown that contributions of interference term between the dark photon and the Standard Model are important. The interference effects are studied and compared with for data sets from TEXONO, GEMMA, BOREXINO, LSND as well as CHARM II experiments. Our results provide more stringent bounds to some regions of parameter space. PACS numbers: 13.15.+g,12.60.+i,14.70.Pw arXiv:1502.07763v2 [hep-ph] 1 Apr 2015 1 CONTENTS I. Introduction 2 II. Hidden Sector as a beyond the Standard Model Scenario 3 III. Neutrino-Electron Scattering 6 A. Standard Model Expressions 6 B. Very Light Vector Boson Contributions 7 IV. Experimental Constraints 9 A. Neutrino-Electron Scattering Experiments 9 B. Roles of Interference 13 C. Results 14 V. Conclusions 17 Acknowledgments 19 References 20 I. INTRODUCTION The recent discovery of the Standard Model (SM) long-sought Higgs at the Large Hadron Collider is the last missing piece of the SM which is strengthened its success even further. -
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. -
Pkoduction of RELATIVISTIC ANTIHYDROGEN ATOMS by PAIR PRODUCTION with POSITRON CAPTURE*
SLAC-PUB-5850 May 1993 (T/E) PkODUCTION OF RELATIVISTIC ANTIHYDROGEN ATOMS BY PAIR PRODUCTION WITH POSITRON CAPTURE* Charles T. Munger and Stanley J. Brodsky Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 .~ and _- Ivan Schmidt _ _.._ Universidad Federico Santa Maria _. - .Casilla. 11 O-V, Valparaiso, Chile . ABSTRACT A beam of relativistic antihydrogen atoms-the bound state (Fe+)-can be created by circulating the beam of an antiproton storage ring through an internal gas target . An antiproton that passes through the Coulomb field of a nucleus of charge 2 will create e+e- pairs, and antihydrogen will form when a positron is created in a bound rather than a continuum state about the antiproton. The - cross section for this process is calculated to be N 4Z2 pb for antiproton momenta above 6 GeV/c. The gas target of Fermilab Accumulator experiment E760 has already produced an unobserved N 34 antihydrogen atoms, and a sample of _ N 760 is expected in 1995 from the successor experiment E835. No other source of antihydrogen exists. A simple method for detecting relativistic antihydrogen , - is -proposed and a method outlined of measuring the antihydrogen Lamb shift .g- ‘,. to N 1%. Submitted to Physical Review D *Work supported in part by Department of Energy contract DE-AC03-76SF00515 fSLAC’1 and in Dart bv Fondo National de InvestiPaci6n Cientifica v TecnoMcica. Chile. I. INTRODUCTION Antihydrogen, the simplest atomic bound state of antimatter, rf =, (e+$, has never. been observed. A 1on g- sought goal of atomic physics is to produce sufficient numbers of antihydrogen atoms to confirm the CPT invariance of bound states in quantum electrodynamics; for example, by verifying the equivalence of the+&/2 - 2.Py2 Lamb shifts of H and I?. -
The Skyrme Model for Baryons
SU–4240–707 MIT–CTP–2880 # The Skyrme Model for Baryons ∗ a , b J. Schechter and H. Weigel† a)Department of Physics, Syracuse University Syracuse, NY 13244–1130 b)Center for Theoretical Physics Laboratory of Nuclear Science and Department of Physics Massachusetts Institute of Technology Cambridge, Ma 02139 ABSTRACT We review the Skyrme model approach which treats baryons as solitons of an ef- fective meson theory. We start out with a historical introduction and a concise discussion of the original two flavor Skyrme model and its interpretation. Then we develop the theme, motivated by the large NC approximation of QCD, that the effective Lagrangian of QCD is in fact one which contains just mesons of all spins. When this Lagrangian is (at least approximately) determined from the meson sector arXiv:hep-ph/9907554v1 29 Jul 1999 it should then yield a zero parameter description of the baryons. We next discuss the concept of chiral symmetry and the technology involved in handling the three flavor extension of the model at the collective level. This material is used to discuss properties of the light baryons based on three flavor meson Lagrangians containing just pseudoscalars and also pseudoscalars plus vectors. The improvements obtained by including vectors are exemplified in the treatment of the proton spin puzzle. ————– #Invited review article for INSA–Book–2000. ∗This work is supported in parts by funds provided by the U.S. Department of Energy (D.O.E.) under cooper- ative research agreements #DR–FG–02–92ER420231 & #DF–FC02–94ER40818 and the Deutsche Forschungs- gemeinschaft (DFG) under contracts We 1254/3-1 & 1254/4-1. -
11. the Cabibbo-Kobayashi-Maskawa Mixing Matrix
11. CKM mixing matrix 103 11. THE CABIBBO-KOBAYASHI-MASKAWA MIXING MATRIX Revised 1997 by F.J. Gilman (Carnegie-Mellon University), where ci =cosθi and si =sinθi for i =1,2,3. In the limit K. Kleinknecht and B. Renk (Johannes-Gutenberg Universit¨at θ2 = θ3 = 0, this reduces to the usual Cabibbo mixing with θ1 Mainz). identified (up to a sign) with the Cabibbo angle [2]. Several different forms of the Kobayashi-Maskawa parametrization are found in the In the Standard Model with SU(2) × U(1) as the gauge group of literature. Since all these parametrizations are referred to as “the” electroweak interactions, both the quarks and leptons are assigned to Kobayashi-Maskawa form, some care about which one is being used is be left-handed doublets and right-handed singlets. The quark mass needed when the quadrant in which δ lies is under discussion. eigenstates are not the same as the weak eigenstates, and the matrix relating these bases was defined for six quarks and given an explicit A popular approximation that emphasizes the hierarchy in the size parametrization by Kobayashi and Maskawa [1] in 1973. It generalizes of the angles, s12 s23 s13 , is due to Wolfenstein [4], where one ≡ the four-quark case, where the matrix is parametrized by a single sets λ s12 , the sine of the Cabibbo angle, and then writes the other angle, the Cabibbo angle [2]. elements in terms of powers of λ: × By convention, the mixing is often expressed in terms of a 3 3 1 − λ2/2 λAλ3(ρ−iη) − unitary matrix V operating on the charge e/3 quarks (d, s,andb): V = −λ 1 − λ2/2 Aλ2 . -
06.08.2010 Yuming Wang the Charm-Loop Effect in B → K () L
The Charm-loop effect in B K( )`+` ! ∗ − Yu-Ming Wang Theoretische Physik I , Universitat¨ Siegen A. Khodjamirian, Th. Mannel,A. Pivovarov and Y.M.W. arXiv:1006.4945 Workshop on QCD and hadron physics, Weihai, August, 2010 1 0 2 4 6 8 10 12 14 16 18 20 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 25 0 2 4 6 8 10 12 14 16 18 20 I. Motivation and introduction ( ) + B K ∗ ` `− induced by b s FCNC current: • prospectiv! e channels for the search! for new physics, a multitude of non-trival observables, Available measurements from BaBar, Belle, and CDF. Current averages (from HFAG, Sep., 2009): • BR(B Kl+l ) = (0:45 0:04) 10 6 ! − × − BR(B K l+l ) = (1:08+0:12) 10 6 : ! ∗ − 0:11 × − Invariant mass distribution and FBA (Belle,−2009): ) 2 1.2 /c 1 2 1 L / GeV 0.5 0.8 F -7 (10 0.6 2 0 0.4 1 0.2 dBF/dq 0.5 ) 0 FB 2 A /c 2 0.5 0 0.4 / GeV -7 0.3 (10 1 2 0.2 I A 0 0.1 dBF/dq 0 -1 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 25 0 2 4 6 8 10 12 14 16 18 20 q2(GeV2/c2) q2(GeV2/c2) Yu-Ming Wang Workshop on QCD and hadron physics, Weihai, August, 2010 2 q2(GeV2/c2) q2(GeV2/c2) Decay amplitudes in SM: • A(B K( )`+` ) = K( )`+` H B ; ! ∗ − −h ∗ − j eff j i 4G 10 H = F V V C (µ)O (µ) ; eff p tb ts∗ i i − 2 iX=1 Leading contributions from O and O can be reduced to B K( ) 9;10 7γ ! ∗ form factors. -
On the Possibility of Experimental Detection of Virtual Particles in Physical Vacuum Anatolii Pavlenko* Open International University of Human Development, Ukraine
onm Pavlenko, J Environ Hazard 2018, 1:1 nvir en f E ta o l l H a a n z r a r u d o J Journal of Environmental Hazards ReviewResearch Article Article OpenOpen Access Access On the Possibility of Experimental Detection of Virtual Particles in Physical Vacuum Anatolii Pavlenko* Open International University of Human Development, Ukraine Abstract The article that you are about to read may surprise you because it looks at problems whose origin is little known and which are rarely taken into account. These problems are real and it is logical to think that the recent and large- scale multiplication of antennas and wind turbines with their earthing in pathogenic zones and the mobile telephony induce fields which modify the natural equilibrium of the soil and have effects on the biosphere. The development of new technologies, such as wind turbines or antennas, such as mobile telephony, induces new forms of pollution that spread through soil faults and can have a negative impact on the health of humans and animals. In the article we share our experience which led us to understand the link between some of these installations and the disorders observed in humans or animals. This is an attempt to change the presentation of the problem of protecting people from the negative impact of electronic technology in public opinion by explaining the reality of virtual particles and their impact on people. We are trying to widely discuss this propaganda about virtual particles. This is an attempt to deduce a discussion on the need to protect against the negative impact of electronic technology on the living in the realm of the radical. -
Antineutron Oscillation Theory
RecentRecent ProgressProgress inin Neutron-Neutron- AntineutronAntineutron OscillationOscillation TheoryTheory MichaelMichael WagmanWagman (UW/INT)(UW/INT) QuarkQuark ConfinementConfinement andand thethe HadronHadron SpectrumSpectrum XIIXII withwith MichaelMichael Buchoff,Buchoff, EnricoEnrico Rinaldi,Rinaldi, ChrisChris Schroeder,Schroeder, andand JoeJoe WasemWasem (LLNL),(LLNL), andand SergeySergey SyritsynSyritsyn (Jefferson(Jefferson Lab/StonyLab/Stony Brook)Brook) 1 Neutron-Antineutron Oscillations violates fundamental symmetries of baryon number and , sensitive to different physics than proton decay Testable signature of possible BSM baryogenesis mechanisms explaining matter-antimatter asymmetry 2 Neutron-Antineutron Phenomenology Similarities to kaon, neutrino oscillations Magnetic fields, nuclear interactions modify transition rate Mohapatra (2009) 3 Experimental Constraints 4 Experimental Outlook European Spallation Source could have 1000 times ILL sensitivity, probe 30 times higher within next decade 5 Neutron-Antineutron Theory: The Standard Model and Beyond Theory must make robust predictions for to reliably interpret the constraints from these experiments Lattice QCD Renormalization Group BSM QCD max lattice BSM strong resolution physics? 6 Baryogenesis Baryon asymmetry and produced by same interactions in several BSM theories Post-sphaleron baryogenesis in e.g. left-right symmetric theories predicts there is a theoretical upper bound on Babu, Dev, Fortes, and Mohapatra (2013) Planck Mohapatra and Marshak (1980) 7 Six-Quark