From Symmetries to Quarks and Beyond 1. Introduction in This Paper
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The Role of Strangeness in Ultrarelativistic Nuclear
HUTFT THE ROLE OF STRANGENESS IN a ULTRARELATIVISTIC NUCLEAR COLLISIONS Josef Sollfrank Research Institute for Theoretical Physics PO Box FIN University of Helsinki Finland and Ulrich Heinz Institut f ur Theoretische Physik Universitat Regensburg D Regensburg Germany ABSTRACT We review the progress in understanding the strange particle yields in nuclear colli sions and their role in signalling quarkgluon plasma formation We rep ort on new insights into the formation mechanisms of strange particles during ultrarelativistic heavyion collisions and discuss interesting new details of the strangeness phase di agram In the main part of the review we show how the measured multistrange particle abundances can b e used as a testing ground for chemical equilibration in nuclear collisions and how the results of such an analysis lead to imp ortant con straints on the collision dynamics and spacetime evolution of high energy heavyion reactions a To b e published in QuarkGluon Plasma RC Hwa Eds World Scientic Contents Introduction Strangeness Pro duction Mechanisms QuarkGluon Pro duction Mechanisms Hadronic Pro duction Mechanisms Thermal Mo dels Thermal Parameters Relative and Absolute Chemical Equilibrium The Partition Function The Phase Diagram of Strange Matter The Strange Matter Iglo o Isentropic Expansion Trajectories The T ! Limit of the Phase Diagram -
Nucleon Resonances and Quark Structure
Nucleon Resonances and Quark Structure J.T. Londergan Physics Dept and Nuclear Theory Center, Indiana University, Bloomington, IN 47405, USA. [email protected] (Dated: October 25, 2018) A pedagogical review of the past 50 years of study of resonances, leading to our understanding of the quark content of baryons and mesons. The level of this review is intended for undergraduates or first-year graduate students. Topics covered include: the quark structure of the proton as revealed through deep inelastic scattering; structure functions and what they reveal about proton structure; and prospects for further studies with new and upgraded facilities, particularly a proposed electron- ion collider. Keywords: I. INTRODUCTION These lectures were given at Aligarh Muslim University, Aligarh India, at a nuclear physics workshop attended by Indian graduate students and postdocs. These lectures provide a pedagogical review of the past 50 years of experimental and theoretical studies of the quark and gluon structure of the nucleon. Since many speakers at this workshop will discuss structure functions extracted from deep inelastic scattering reactions, we define these quantities and review what can be extracted from them. We hope that specialists in this field will tolerate our brief and superficial summary of many years' study of strongly-interacting systems. FIG. 1: Richard H. Dalitz, 1925-2006. arXiv:0907.3431v1 [hep-ph] 20 Jul 2009 These lectures are dedicated to my mentor, Richard Dalitz, who was from 1963-2000 Royal Society Professor of Physics at Oxford University and who made seminal contributions in particle phenomenology. Dalitz pairs (electron- positron pairs from decay of a high-energy photon) and the Dalitz plot were named after him. -
Tcomposite Weak Bosons, Leptons and Quarks
Subnuclear Physics: Past, Present and Future Pontifical Academy of Sciences, Scripta Varia 119, Vatican City 2014 www.pas.va/content/dam/accademia/pdf/sv119/sv119-fritzsch.pdf TComposite Weak Bosons, Leptons and Quarks HARALD FRITZSCH University of Munich Faculty of Physics, Arnold Sommerfeld Center for Theoretical Physics, Abstract The weak bosons consist of two fermions, bound by a new confin- ing gauge force. The mass scale of this new interaction is determined. At energies below 0.5 TeV the standard electroweak theory is valid. AneutralisoscalarweakbosonX must exist - its mass is less than 1TeV.Itwilldecaymainlyintoquarkandleptonpairsandintotwo or three weak bosons. Above the mass of 1 TeV one finds excitations of the weak bosons, which mainly decay into pairs of weak bosons. Leptons and quarks consist of a fermion and a scalar. Pairs of leptons and pairs of quarks form resonances at very high energy. 280 Subnuclear Physics: Past, Present and Future COMPOSITE WEAK BOSONS, LEPTONS AND QUARKS In the Standard Model the leptons, quarks and weak bosons are pointlike particles. I shall assume that they are composite particles with a finite size. The present limit on the size of the electron, the muon and of the light quarks is about 10−17 cm. The constituents of the weak bosons and of the leptons and quarks are bound by a new confining gauge interaction. Due to the parity violation in the weak interactions this theory must be a chiral gauge theory, unlike quantum chromodynamics. The Greek translation of ”simple” is ”haplos”. We denote the con- stituents as ”haplons” and the new confining gauge theory as quantum hap- lodynamics ( QHD ). -
Estimation of Baryon Asymmetry of the Universe from Neutrino Physics
ESTIMATION OF BARYON ASYMMETRY OF THE UNIVERSE FROM NEUTRINO PHYSICS Manorama Bora Department of Physics Gauhati University This thesis is submitted to Gauhati University as requirement for the degree of Doctor of Philosophy Faculty of Science March 2018 I would like to dedicate this thesis to my parents . Abstract The discovery of neutrino masses and mixing in neutrino oscillation experiments in 1998 has greatly increased the interest in a mechanism of baryogenesis through leptogenesis, a model of baryogenesis which is a cosmological consequence. The most popular way to explain why neutrinos are massive but at the same time much lighter than all other fermions, is the see-saw mechanism. Thus, leptogenesis realises a highly non-trivial link between two completely independent experimental observations: the absence of antimatter in the observable universe and the observation of neutrino mixings and masses. Therefore, leptogenesis has a built-in double sided nature.. The discovery of Higgs boson of mass 125GeV having properties consistent with the SM, further supports the leptogenesis mechanism. In this thesis we present a brief sketch on the phenomenological status of Standard Model (SM) and its extension to GUT with or without SUSY. Then we review on neutrino oscillation and its implication with latest experiments. We discuss baryogenesis via leptogenesis through the decay of heavy Majorana neutrinos. We also discuss formulation of thermal leptogenesis. At last we try to explore the possibilities for the discrimination of the six kinds of Quasi- degenerate neutrino(QDN)mass models in the light of baryogenesis via leptogenesis. We have seen that all the six QDN mass models are relevant in the context of flavoured leptogenesis. -
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. -
An Introduction to the Quark Model
An Introduction to the Quark Model Garth Huber Prairie Universities Physics Seminar Series, November, 2009. Particles in Atomic Physics • View of the particle world as of early 20th Century. • Particles found in atoms: –Electron – Nucleons: •Proton(nucleus of hydrogen) •Neutron(e.g. nucleus of helium – α-particle - has two protons and two neutrons) • Related particle mediating electromagnetic interactions between electrons and protons: Particle Electric charge Mass – Photon (light!) (x 1.6 10-19 C) (GeV=x 1.86 10-27 kg) e −1 0.0005 p +1 0.938 n 0 0.940 γ 0 0 Dr. Garth Huber, Dept. of Physics, Univ. of Regina, Regina, SK S4S0A2, Canada. 2 Early Evidence for Nucleon Internal Structure • Apply the Correspondence Principle to the Classical relation for q magnetic moment: µ = L 2m • Obtain for a point-like spin-½ particle of mass mp: qqeq⎛⎞⎛⎞ µ == =µ ⎜⎟ ⎜⎟ N 2222memepp⎝⎠ ⎝⎠ 2 Experimental values: µp=2.79 µN (p) µn= -1.91 µN (n) • Experimental values inconsistent with point-like assumption. • In particular, the neutron’s magnetic moment does not vanish, as expected for a point-like electrically neutral particle. This is unequivocal evidence that the neutron (and proton) has an internal structure involving a distribution of charges. Dr. Garth Huber, Dept. of Physics, Univ. of Regina, Regina, SK S4S0A2, Canada. 3 The Particle Zoo • Circa 1950, the first particle accelerators began to uncover many new particles. • Most of these particles are unstable and decay very quickly, and hence had not been seen in cosmic ray experiments. • Could all these particles be fundamental? Dr. Garth Huber, Dept. -
1 Quark Model of Hadrons
1 QUARK MODEL OF HADRONS 1 Quark model of hadrons 1.1 Symmetries and evidence for quarks 1 Hadrons as bound states of quarks – point-like spin- 2 objects, charged (‘coloured’) under the strong force. Baryons as qqq combinations. Mesons as qq¯ combinations. 1 Baryon number = 3 (N(q) − N(¯q)) and its conservation. You are not expected to know all of the names of the particles in the baryon and meson multiplets, but you are expected to know that such multiplets exist, and to be able to interpret them if presented with them. You should also know the quark contents of the simple light baryons and mesons (and their anti-particles): p = (uud) n = (udd) π0 = (mixture of uu¯ and dd¯) π+ = (ud¯) K0 = (ds¯) K+ = (us¯). and be able to work out others with some hints. P 1 + Lowest-lying baryons as L = 0 and J = 2 states of qqq. P 3 + Excited versions have L = 0 and J = 2 . Pauli exclusion and non existence of uuu, ddd, sss states in lowest lying multiplet. Lowest-lying mesons as qq¯0 states with L = 0 and J P = 0−. First excited levels (particles) with same quark content have L = 0 and J P = 1−. Ability to explain contents of these multiplets in terms of quarks. J/Ψ as a bound state of cc¯ Υ (upsilon) as a bound state of b¯b. Realization that these are hydrogenic-like states with suitable reduced mass (c.f. positronium), and subject to the strong force, so with energy levels paramaterized by αs rather than αEM Top is very heavy and decays before it can form hadrons, so no top hadrons exist. -
The Structure of Quarks and Leptons
The Structure of Quarks and Leptons They have been , considered the elementary particles ofmatter, but instead they may consist of still smaller entities confjned within a volume less than a thousandth the size of a proton by Haim Harari n the past 100 years the search for the the quark model that brought relief. In imagination: they suggest a way of I ultimate constituents of matter has the initial formulation of the model all building a complex world out of a few penetrated four layers of structure. hadrons could be explained as combina simple parts. All matter has been shown to consist of tions of just three kinds of quarks. atoms. The atom itself has been found Now it is the quarks and leptons Any theory of the elementary particles to have a dense nucleus surrounded by a themselves whose proliferation is begin fl. of matter must also take into ac cloud of electrons. The nucleus in turn ning to stir interest in the possibility of a count the forces that act between them has been broken down into its compo simpler-scheme. Whereas the original and the laws of nature that govern the nent protons and neutrons. More recent model had three quarks, there are now forces. Little would be gained in simpli ly it has become apparent that the pro thought to be at least 18, as well as six fying the spectrum of particles if the ton and the neutron are also composite leptons and a dozen other particles that number of forces and laws were thereby particles; they are made up of the small act as carriers of forces. -
Interactions the Newsletter of the UB Department of Physics Volume 4, Issue 2 Fall 2011
Interactions The Newsletter of the UB Department of Physics Volume 4, Issue 2 Fall 2011 established well formulated procedures for all the graduate studies. He continues to be a source of information and ad- vice for our graduate program. Our majors, headed by Alec Cheney, were instrumental in starting a new chapter of the Sigma Pi Sigma, the Phys- ics Honors Society, at UB. They collected signatures and petitioned the Society for a UB chapter. After successfully receiving approval, they also made arrangements for the installation. The President of the Sigma PI Sigma, Dr. Di- ane Jacobs, presided the chapter installation ceremony on November 4. Five students, Alec Cheney, Matthew Gorfien, Connor Gorman, Chun Kwan and Katherine Spoth, were in- Dear alumni and friends, ducted during the ceremony. It was very rewarding to see As I mentioned in the previous issue, the new President and our majors take charge, accomplish their goals and receive the Dean of CAS are now in office. The SUNY2020 legisla- recognition for their outstanding achievements. tion was passed and signed into law, which allows UB for This year’s Homecoming was made special by the return of the first time to plan on a five-year horizon. The new direc- our distinguished alumnus, Dr. Thomas Bogdan (featured tions and initiatives that are being implemented by the new in Alumni in Focus), to give an exciting public lecture on administration are therefore more tangible than symbolic. space weather. He has been the Director of the National This means opportunities for the Department. It is encour- Space Weather Prediction Center, and was recently named aging to see that the President’s plan for the University over- the President of the University Corporation for Atmospheric laps with some of the main concerns and aspirations of the Research, starting January 9, 2012. -
Strange Particle Theory in the Cosmic Ray Period R
STRANGE PARTICLE THEORY IN THE COSMIC RAY PERIOD R. Dalitz To cite this version: R. Dalitz. STRANGE PARTICLE THEORY IN THE COSMIC RAY PERIOD. Journal de Physique Colloques, 1982, 43 (C8), pp.C8-195-C8-205. 10.1051/jphyscol:1982811. jpa-00222371 HAL Id: jpa-00222371 https://hal.archives-ouvertes.fr/jpa-00222371 Submitted on 1 Jan 1982 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. JOURNAL DE PHYSIQUE Colloque C8, suppldment au no 12, Tome 43, ddcembre 1982 page ~8-195 STRANGE PARTICLE THEORY IN THE COSMIC RAY PERIOD R.H. Dalitz Department of Theoretical Physics, 2 KebZe Road, Oxford OX1 3NP, U.K. What role did theoretical physicists play concerning elementary particle physics in the cosmic ray period? The short answer is that it was the nuclear forces which were the central topic of their attention at that time. These were considered to be due primarily to the exchange of pions between nucleons, and the study of all aspects of the pion-nucleon interactions was the most direct contribution they could make to this problem. Of course, this was indeed a most important topic, and much significant understanding of the pion-nucleon interaction resulted from these studies, although the precise nature of the nucleonnucleon force is not settled even to this day. -
Richard Feynman by Harald Fritzsch
ARTSCIENCE MUSEUM™ PRESENTS ALL POSSIBLE Harald Fritzsch Richard Feynman RICHARD FEYNMAN’S CURIOUS LIFE In 1968, I escaped from East Germany with a folding canoe, crossing the Black In 1975, Feynman bought a Dodge Tradesman Maxivan and had it painted with Sea from Northern Bulgaria to Turkey. Then I worked as a Ph.D. student at the Feynman diagrams. Once, we were going camping with Feynman and his wife Max-Planck-Institute in Munich. In the Fall of 1970, I went for 6 months to the in the Anza Borrego desert park near Palm Springs. Feyman drove his big Stanford Linear Accelerator Center (SLAC) in Palo Alto, California. Since at that camping car. On the way back, Feynman stopped at a gas station in Palm time I collaborated with Murray Gell-Mann, I went twice a month for a few days Springs. The guy at the station asked Feynman: “Why you have these to the California Institute of Technology (Caltech) in Pasadena, about 360 miles Feynman Diagrams on your car?” Feynman told him, that he is Feynman, and south from Palo Alto. the guy answered: “Well, in this case you do not have to pay for the gasoline.” In Caltech I met Richard Feynman for the first time, and we discussed physics Feynman had a house at the beach near Ensenada in Baja California, Mexico. almost every day, in particular his parton model. He assumed that the nucleons He called the house “Casita Barranca”. Feynman invited us to plan a visit to consist of small pointlike constituents, which he called partons. -
The Matter – Antimatter Asymmetry of the Universe and Baryogenesis
The matter – antimatter asymmetry of the universe and baryogenesis Andrew Long Lecture for KICP Cosmology Class Feb 16, 2017 Baryogenesis Reviews in General • Kolb & Wolfram’s Baryon Number Genera.on in the Early Universe (1979) • Rio5o's Theories of Baryogenesis [hep-ph/9807454]} (emphasis on GUT-BG and EW-BG) • Rio5o & Trodden's Recent Progress in Baryogenesis [hep-ph/9901362] (touches on EWBG, GUTBG, and ADBG) • Dine & Kusenko The Origin of the Ma?er-An.ma?er Asymmetry [hep-ph/ 0303065] (emphasis on Affleck-Dine BG) • Cline's Baryogenesis [hep-ph/0609145] (emphasis on EW-BG; cartoons!) Leptogenesis Reviews • Buchmuller, Di Bari, & Plumacher’s Leptogenesis for PeDestrians, [hep-ph/ 0401240] • Buchmulcer, Peccei, & Yanagida's Leptogenesis as the Origin of Ma?er, [hep-ph/ 0502169] Electroweak Baryogenesis Reviews • Cohen, Kaplan, & Nelson's Progress in Electroweak Baryogenesis, [hep-ph/ 9302210] • Trodden's Electroweak Baryogenesis, [hep-ph/9803479] • Petropoulos's Baryogenesis at the Electroweak Phase Transi.on, [hep-ph/ 0304275] • Morrissey & Ramsey-Musolf Electroweak Baryogenesis, [hep-ph/1206.2942] • Konstandin's Quantum Transport anD Electroweak Baryogenesis, [hep-ph/ 1302.6713] Constituents of the Universe formaon of large scale structure (galaxy clusters) stars, planets, dust, people late ame accelerated expansion Image stolen from the Planck website What does “ordinary matter” refer to? Let’s break it down to elementary particles & compare number densities … electron equal, universe is neutral proton x10 billion 3⇣(3) 3 3 n =3 T 168 cm− neutron x7 ⌫ ⇥ 4⇡2 ⌫ ' matter neutrinos photon positron =0 2⇣(3) 3 3 n = T 413 cm− γ ⇡2 CMB ' anti-proton =0 3⇣(3) 3 3 anti-neutron =0 n =3 T 168 cm− ⌫¯ ⇥ 4⇡2 ⌫ ' anti-neutrinos antimatter What is antimatter? First predicted by Dirac (1928).