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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. -
Effective Field Theories for Quarkonium
Effective Field Theories for Quarkonium recent progress Antonio Vairo Technische Universitat¨ Munchen¨ Outline 1. Scales and EFTs for quarkonium at zero and finite temperature 2.1 Static energy at zero temperature 2.2 Charmonium radiative transitions 2.3 Bottomoniun thermal width 3. Conclusions Scales and EFTs Scales Quarkonia, i.e. heavy quark-antiquark bound states, are systems characterized by hierarchies of energy scales. These hierarchies allow systematic studies. They follow from the quark mass M being the largest scale in the system: • M ≫ p • M ≫ ΛQCD • M ≫ T ≫ other thermal scales The non-relativistic expansion • M ≫ p implies that quarkonia are non-relativistic and characterized by the hierarchy of scales typical of a non-relativistic bound state: M ≫ p ∼ 1/r ∼ Mv ≫ E ∼ Mv2 The hierarchy of non-relativistic scales makes the very difference of quarkonia with heavy-light mesons, which are just characterized by the two scales M and ΛQCD. Systematic expansions in the small heavy-quark velocity v may be implemented at the Lagrangian level by constructing suitable effective field theories (EFTs). ◦ Brambilla Pineda Soto Vairo RMP 77 (2004) 1423 Non-relativistic Effective Field Theories LONG−RANGE SHORT−RANGE Caswell Lepage PLB 167(86)437 QUARKONIUM QUARKONIUM / QED ◦ ◦ Lepage Thacker NP PS 4(88)199 QCD/QED ◦ Bodwin et al PRD 51(95)1125, ... M perturbative matching perturbative matching ◦ Pineda Soto PLB 420(98)391 µ ◦ Pineda Soto NP PS 64(98)428 ◦ Brambilla et al PRD 60(99)091502 Mv NRQCD/NRQED ◦ Brambilla et al NPB 566(00)275 ◦ Kniehl et al NPB 563(99)200 µ ◦ Luke Manohar PRD 55(97)4129 ◦ Luke Savage PRD 57(98)413 2 non−perturbative perturbative matching Mv matching ◦ Grinstein Rothstein PRD 57(98)78 ◦ Labelle PRD 58(98)093013 ◦ Griesshammer NPB 579(00)313 pNRQCD/pNRQED ◦ Luke et al PRD 61(00)074025 ◦ Hoang Stewart PRD 67(03)114020, .. -
Quarkonium Interactions in QCD1
CERN-TH/95-342 BI-TP 95/41 Quarkonium Interactions in QCD1 D. KHARZEEV Theory Division, CERN, CH-1211 Geneva, Switzerland and Fakult¨at f¨ur Physik, Universit¨at Bielefeld, D-33501 Bielefeld, Germany CONTENTS 1. Introduction 1.1 Preview 1.2 QCD atoms in external fields 2. Operator Product Expansion for Quarkonium Interactions 2.1 General idea 2.2 Wilson coefficients 2.3 Sum rules 2.4 Absorption cross sections 3. Scale Anomaly, Chiral Symmetry and Low-Energy Theorems 3.1 Scale anomaly and quarkonium interactions 3.2 Low energy theorem for quarkonium interactions with pions 3.3 The phase of the scattering amplitude 4. Quarkonium Interactions in Matter 4.1 Nuclear matter 4.2 Hadron gas 4.3 Deconfined matter 5. Conclusions and Outlook 1Presented at the Enrico Fermi International School of Physics on “Selected Topics in Non-Perturbative QCD”, Varenna, Italy, June 1995; to appear in the Proceedings. 1 Introduction 1.1 Preview Heavy quarkonia have proved to be extremely useful for understanding QCD. The large mass of heavy quarks allows a perturbation theory analysis of quarkonium decays [1] (see [2] for a recent review). Perturbation theory also provides a rea- sonable first approximation to the correlation functions of quarkonium currents; deviations from the predictions of perturbation theory can therefore be used to infer an information about the nature of non-perturbative effects. This program was first realized at the end of the seventies [3]; it turned out to be one of the first steps towards a quantitative understanding of the QCD vacuum. The natural next step is to use heavy quarkonia to probe the properties of excited QCD vacuum, which may be produced in relativistic heavy ion collisions; this was proposed a decade ago [4]. -
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. -
Searching for a Heavy Partner to the Top Quark
SEARCHING FOR A HEAVY PARTNER TO THE TOP QUARK JOSEPH VAN DER LIST 5e Abstract. We present a search for a heavy partner to the top quark with charge 3 , where e is the electron charge. We analyze data from Run 2 of the Large Hadron Collider at a center of mass energy of 13 TeV. This data has been previously investigated without tagging boosted top quark (top tagging) jets, with a data set corresponding to 2.2 fb−1. Here, we present the analysis at 2.3 fb−1 with top tagging. We observe no excesses above the standard model indicating detection of X5=3 , so we set lower limits on the mass of X5=3 . 1. Introduction 1.1. The Standard Model One of the greatest successes of 20th century physics was the classification of subatomic particles and forces into a framework now called the Standard Model of Particle Physics (or SM). Before the development of the SM, many particles had been discovered, but had not yet been codified into a complete framework. The Standard Model provided a unified theoretical framework which explained observed phenomena very well. Furthermore, it made many experimental predictions, such as the existence of the Higgs boson, and the confirmation of many of these has made the SM one of the most well-supported theories developed in the last century. Figure 1. A table showing the particles in the standard model of particle physics. [7] Broadly, the SM organizes subatomic particles into 3 major categories: quarks, leptons, and gauge bosons. Quarks are spin-½ particles which make up most of the mass of visible matter in the universe; nucleons (protons and neutrons) are composed of quarks. -
10 Progressing Beyond the Standard Models
i i “proc16” — 2016/12/12 — 10:17 — page 177 — #193 i i BLED WORKSHOPS Proceedings to the 19th Workshop IN PHYSICS What Comes Beyond ::: (p. 177) VOL. 17, NO. 2 Bled, Slovenia, July 11–19, 2016 10 Progressing Beyond the Standard Models B.A. Robson ? The Australian National University, Canberra, ACT 2601, Australia Abstract. The Standard Model of particle physics (SMPP) has enjoyed considerable success in describing a whole range of phenomena in particle physics. However, the model is con- sidered incomplete because it provides little understanding of other empirical observations such as the existence of three generations of leptons and quarks, which apart from mass have similar properties. This paper examines the basic assumptions upon which the SMPP is built and compares these with the assumptions of an alternative model, the Generation Model (GM). The GM provides agreement with the SMPP for those phenomena which the SMPP is able to describe, but it is shown that the assumptions inherent in the GM allow progress beyond the SMPP. In particular the GM leads to new paradigms for both mass and gravity. The new theory for gravity provides an understanding of both dark matter and dark energy, representing progress beyond the Standard Model of Cosmology (SMC). Povzetek. Standardni Model elektrosibkeˇ in barvne interakcije zelo uspesnoˇ opiseˇ veliko pojavov v fiziki osnovnih delcev. Model imajo kljub temu za nepopoln, ker ne pojasni vrste empiricnihˇ dejstev, kot je obstoj treh generacij leptonov in kvarkov, ki imajo, razen razlicnihˇ mas, zelo podobne lastnosti. V prispevku obravnavamo osnovne predpostavke, na katerih so zgradili ta model in jih primerjamo s predpostavkami alternativnega modela, generacijskega modela. -
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. -
The Flavour Puzzle, Discreet Family Symmetries
The flavour puzzle, discreet family symmetries 27. 10. 2017 Marek Zrałek Particle Physics and Field Theory Department University of Silesia Outline 1. Some remarks about the history of the flavour problem. 2. Flavour in the Standard Model. 3. Current meaning of the flavour problem? 4. Discrete family symmetries for lepton. 4.1. Abelian symmetries, texture zeros. 4.2. Non-abelian symmetries in the Standard Model and beyond 5. Summary. 1. Some remarks about the history of the flavour problem The flavour problem (History began with the leptons) I.I. Rabi Who ordered that? Discovered by Anderson and Neddermayer, 1936 - Why there is such a duplication in nature? - Is the muon an excited state of the electron? - Great saga of the µ → e γ decay, (Hincks and Pontecorvo, 1948) − − - Muon decay µ → e ν ν , (Tiomno ,Wheeler (1949) and others) - Looking for muon – electron conversion process (Paris, Lagarrigue, Payrou, 1952) Neutrinos and charged leptons Electron neutrino e− 1956r ν e 1897r n p Muon neutrinos 1962r Tau neutrinos − 1936r ν µ µ 2000r n − ντ τ 1977r p n p (Later the same things happen for quark sector) Eightfold Way Murray Gell-Mann and Yuval Ne’eman (1964) Quark Model Murray Gell-Mann and George Zweig (1964) „Young man, if I could remember the names of these particles, I „Had I foreseen that, I would would have been a botanist”, have gone into botany”, Enrico Fermi to advise his student Leon Wofgang Pauli Lederman Flavour - property (quantum numbers) that distinguishes Six flavours of different members in the two groups, quarks and -
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