Strange Particle Theory in the Cosmic Ray Period R
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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 -
Detection of a Strange Particle
10 extraordinary papers Within days, Watson and Crick had built a identify the full set of codons was completed in forensics, and research into more-futuristic new model of DNA from metal parts. Wilkins by 1966, with Har Gobind Khorana contributing applications, such as DNA-based computing, immediately accepted that it was correct. It the sequences of bases in several codons from is well advanced. was agreed between the two groups that they his experiments with synthetic polynucleotides Paradoxically, Watson and Crick’s iconic would publish three papers simultaneously in (see go.nature.com/2hebk3k). structure has also made it possible to recog- Nature, with the King’s researchers comment- With Fred Sanger and colleagues’ publica- nize the shortcomings of the central dogma, ing on the fit of Watson and Crick’s structure tion16 of an efficient method for sequencing with the discovery of small RNAs that can reg- to the experimental data, and Franklin and DNA in 1977, the way was open for the com- ulate gene expression, and of environmental Gosling publishing Photograph 51 for the plete reading of the genetic information in factors that induce heritable epigenetic first time7,8. any species. The task was completed for the change. No doubt, the concept of the double The Cambridge pair acknowledged in their human genome by 2003, another milestone helix will continue to underpin discoveries in paper that they knew of “the general nature in the history of DNA. biology for decades to come. of the unpublished experimental results and Watson devoted most of the rest of his ideas” of the King’s workers, but it wasn’t until career to education and scientific administra- Georgina Ferry is a science writer based in The Double Helix, Watson’s explosive account tion as head of the Cold Spring Harbor Labo- Oxford, UK. -
Negative Strange Quark-Chemical Potential a Necessary and Sufficient Observable of the Deconfinement Phase Transition in a Finite-Baryon Equilibrated State*
Negative strange quark-chemical potential A necessary and sufficient observable of the deconfinement phase transition in a finite-baryon equilibrated state* Apostolos D. Panagiotou and Panayiotis Katsas University of Athens, Physics Department Nuclear & Particle Physics Division Panepistimiopolis, GR-157 71 Athens, Hellas Abstract We consider the variation of the strange quark-chemical potential in the phase diagramme of nuclear matter, employing the order parameters and mass-scaled partition functions in each domain and enforcing flavour conservation. Assuming the region beyond the hadronic phase to be described by massive, correlated and interacting quarks, in the spirit of lattice and N−J-L calculations, we find the strange quark-chemical potential to attain large negative values in this domain. We propose that this change in the sign of the strange quark- chemical potential, from positive in the hadronic phase to negative in the partonic, to be a unique, concise and well-defined indication of the quark-deconfinement phase transition in nuclear matter. We propose also that, for a chemically equilibrated state in the deconfined region, which follows an isentropic expansion to hadronization via a second order phase transition, the fugacities of the equilibrated quark flavours, once fixed in the primordial state, remain constant throughout the hadronization process. PACS codes: 25.75.+r,12.38.Mh,24.84.+p Key words: Quark-chemical potential, phase transition, deconfined quark matter, HG, QGP e-mail: [email protected] * Work supported in part by the Research Secretariat of the University of Athens. 1. Introduction It is generally expected that ultra-relativistic nucleus-nucleus collisions will provide the basis for strong interaction thermodynamics, which will lead to new physics. -
Precision Cross Section Measurements in Hall C
Precision Cross Section Measurements in Hall C Hall C focusing spectrometers Tanja Horn Neutral Particle Spectrometer 3D Nucleon Tomography Workshop March 15-17, 2017, Jefferson Lab 1 The 3D Nucleon Structure Generalized Parton and Transverse Momentum Distributions are essential for our understanding of internal hadron structure and the dynamics that bind the most basic elements of Nuclear Physics 5D TMDs – Confined motion in a nucleon (semi-inclusive DIS) 3D GPDs – Spatial imaging (exclusive DIS) Requires − High luminosity − Polarized beams and targets Major new capability with JLab12 2 NSAC 2015 Long Range Plan “Precision measurements in semi-inclusive pion and kaon production from unpolarized, as well as longitudinally and transversely polarized proton … targets in the JLab 12 GeV era will allow access to both flavor and spin dependent transverse momentum distributions in the valence quark region.” “Multiple instruments bring essential elements to this campaign: … HMS-SHMS and the … NPS” “Some of the most important tools for describing hadrons are Generalized Parton Distributions, [which] can be investigated through the analysis of hard exclusive processes” “The HMS-SHMS …[and] the NPS will allow …refined high resolution imaging of the nucleon’s internal landscape…” Experimental Access to GPDs: DVCS See also talks by, e.g. F-X Girod, C. Hyde Cleanest way to probe GPDs As the DVCS process interferes with BH one can access the DVCS amplitudes 4 Towards spin-flavor separation: DVMP See also talks by, e.g. F-X Girod, C. Hyde Exclusive -
Charged Current Events with Neutral Strange Particles in High-Energy Antineutrino Interactions
Nuclear Physics B177 (1981) 365-381 O North-Holland Publishing Company CHARGED CURRENT EVENTS WITH NEUTRAL STRANGE PARTICLES IN HIGH-ENERGY ANTINEUTRINO INTERACTIONS V.V. AMMOSOV, A.G. DENISOV, P.F. ERMOLOV, G.S. GAPIENKO, V.A. GAPIENKO, V.I. KLUKHIN, V.I. KORESHEV, P.V. PITUKHIN, V.I. SIROTENKO, E.A. SLOBODYUK, Z.V. USUBOV and V.G. ZAETZ Institute of High Energy Physics, Serpukhov, U$SR J.P. BERGE, D. BOGERT, R. ENDORF 1, R. HANFT, J.A. MALKO, G.I. MOFFATT 1, F.A. NEZRICK, R. ORAVA and J. WOLFSON Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA V.I. EFREMENKO, A.V. FEDOTOV, P.A. GORICHEV, V.S. KAFTANOV, G.K. KLIGER, V.Z. KOLGANOV, S.P. KRUTCHININ, M.A. KUBANTSEV, I.V. MAKHLJUEVA, V.I. SHEKELJAN and V.G. SHEVCHENKO Institute for Theoretical and Experimental Physics, MosCow, USSR J. BELL, C.T. COFFIN, B.P. ROE, A.A. SEIDL, D. SINCLAIR and E. WANG University of Michigan, Ann Arbor, Michigan 48104, USA Received 23 May 1980 (Revised 5 August 1980) The results of a study of strange particle production in charged current 77,N interactions in the Fermilab 15 ft bubble chamber filled with a heavy Ne-H2 mixture are presented. Production rates and average multiplicities of K°'s and A's as functions of W 2 and Q2 are given. The experimental data agree well with the quark-parton model predictions if a yield of 0.06 + 0.02 of K°'s and A's from charm production is included. Upper limits for D-meson production are given and the shape of the charmed quark fragmentation function is discussed. -
Astrophysical Relevance of Strange Quarks
Available online a t www.scholarsresearchlibrary.com Scholars Research Library Archives of Physics Research, 2010, 1 (3):89-110 (http://scholarsresearchlibrary.com/archive.html) ISSN 0976-0970 CODEN (USA): APRRC7 Astrophysical relevance of Strange Quarks Navjot Hothi† and Shuchi Bisht * Department of Physics, Kumaun University, Nainital, Uttrakhand, India ______________________________________________________________________________ ABSTRACT In this contribution, peculiarities in the nature of strange quarks in relevance to astrophysics are investigated. The absolute stability of strange quark matter is a viable possibility and immensely affects physics at the astrophysical scale. Relativistic heavy-ion reactions offer a stage to produce this exotic state of matter and we have discussed the enhanced production of strange particles during these reactions within the framework of quark-gluon plasma (QGP) along with its observable implications. The role of strangeness for compact star phenomenology is explored. Emphasis is laid upon the possibility of existence of a third family of strange quark stars and its study help in revealing a number of unexplored features of the cosmos. Bag model parameters have been used to determine some integral parameters for a sequence of strange stars with crust and strange dwarfs constructed out of strange quark matter crust. A comparative analysis is performed between the strange and neutron stars and the strange and white dwarfs based upon these intrinsic parameters and paramount differences are observed. PACS numbers: 12.38.Mh, 25.75.Nq, 14.65.-q, 97.60.Jd, 26.60.-c Keywords: strangeness, strange stars, quark-gluon plasma, deconfinement. ______________________________________________________________________________ INTRODUCTION The last few years witnessed the inclusion of strangeness as another degree of freedom in astrophysical systems. -
1 Historical Introduction to the Elementary Particles
13 1 Historical Introduction to the Elementary Particles This chapter is a kind of ‘folk history’ of elementary particle physics. Its purpose is to provide a sense of how the various particles were first discovered, and how they fit into the overall scheme of things. Along the way some of the fundamental ideas that dominate elementary particle theory are explained. This material should be read quickly, as background to the rest of the book. (As history, the picture presented here is certainly misleading, for it sticks closely to the main track, ignoring the false starts and blind alleys that accompany the development of any science. That’s why I call it ‘folk’ history – it’s the way particle physicists like to remember the subject – a succession of brilliant insights and heroic triumphs unmarred by foolish mistakes, confusion, and frustration. It wasn’t really quite so easy.) 1.1 The Classical Era (1897–1932) It is a little artificial to pinpoint such things, but I’d say that elementary particle physics was born in 1897, with J. J. Thomson’s discovery of the electron [1]. (It is fashionable to carry the story all the way back to Democritus and the Greek atomists, but apart from a few suggestive words their metaphysical speculations have nothing in common with modern science, and although they may be of modest antiquarian interest, their genuine relevance is negligible.) Thomson knew that cathode rays emitted by a hot filament could be deflected by a magnet. This suggested that they carried electric charge; in fact, the direction of the curvature required that the charge be negative. -
Nljkü^EF NATIONAAL INSTITUUT VOOR KERNFYSICA EN HOGE-ENERGIEFYSICA
NlJKÜ^EF NATIONAAL INSTITUUT VOOR KERNFYSICA EN HOGE-ENERGIEFYSICA NIKHFl'-H IM-'JI Prospects for direct measurement of time-integrated BH mixing Ivar Siccama XIKÏIKF-II. P.O. Box 41882 100!) DB Amsterdam June 10. 1994 Abstract This note investigates the prospects of measuring time-integrated B, mixing. Three inclusive decay modes of the B, meson are discussed. For each reconstruction mode, the expected number of events and the different background channels are discussed. Estimates are given for the uncertainty on the mixing parameter \,. NIKHEF SECTIE -H POSTBUS 41882,1009 DB AMSTERDAM in KS0Ot934i29 R: FI -— - „nr 0EOO8130736 •DE008130736* 1 Introduction The production of B mesons at LEP is a mixture of B+. B°d and B°} mesons. The time integrated mixing parameter \ is an average quantity that reflects this mixture of Bd and B" mesons: \ = fd\d + f,\s Here \^ is the probability tliat the original B.t meson decays as a B1. and /j and ƒ, are the fractions of B° and B, mesons produced in the fragmentation of the b quark. The combined measurements of ALEPH, DELPHI. L3 and OPAL give [4]: \ = 0.119 ±0.012 From this a value for \, can be deduced l: \s = 0.45 ± 0.07(x-a) ± 0.10(x) ± M ƒ) The error on the value of \, is dominated by the uncertainty in the parameters fd and ƒ,, indicated by A( ƒ). These fractions are model dependent and therefore hard to estimate. In this note fd = 0.4 and ƒ, = 0.12 are used. The value of \<t that was used to deduce \, comes from measurements of CLEO and ARGUS [6, 8] where B mesons are produced below the production threshold of the Bs, at the T(45) resonance: \d = 0.162 ±0.021 A direct way to measure \, is to use an enriched sample of B, mesons. -
Significance of Strangeness Conservation/Violation Studies at BESIII
Proceedings of the Pakistan Academy of Sciences: Pakistan Academy of Sciences A. Physical and Computational Sciences 55 (2): 1–11 (2018) Copyright © Pakistan Academy of Sciences ISSN: 2518-4245 (print), 2518-4253 (online) Review Article Significance of Strangeness Conservation/Violation Studies at BESIII Aneela Amin1 , Khadija Saeed1, Farzana Younas1, and Ghalib ul Islam2 ∗ 1Centre for High Energy Physics, University of the Punjab, Lahore (54590), Pakistan 2Department of Physics, The University of Lahore, Lahore (53700), Pakistan Abstract Strangeness violation and conservation have been studied in Charmonia and its higher state decays. The data of some prominent decay modes has been collected from BESIII laboratory from the years 2009 to date. The strangeness violating decays play an important role in the study of weak interactions. On the other hand, strangeness conserving decays describe the strong interactions. An overview of strangeness conserving decays and strangeness violating decays has been given and the decay modes are presented in tabular form. The study reveals that associated production occurs only in strangeness conserving decays rather than strangeness violating decays. Experimental and theoretical results are presented in order to arrange phenomenological developments and queries may search new domains in Experimental High Energy Physics, and will explore new prospects of strangeness, a basic quantum number of hadrons and its associated production. Keywords: Strangeness, Charmonia, Strangeness conserving decays, Strangeness violating decays, Standard model 1. INTRODUCTION described the interactions among these particles known as Standard Model. According to The study of particles and the interaction between Standard Model, three types of interactions exist them shows that quarks and leptons are the basic among these particles i.e. -
A Study of the Methods of Meson Mass Determination A
A STUDY OF THE METHODS OF MESON MASS DETERMINATION A THESIS Presented to the Faculty of the Division of Graduate Studies Georgia Institute of Technology In Partial Fulfillment of the Requirements for the Degree Master of Science in Physics by Gilbert Carl Knollman June 1950 r 642 ii A STUDY OF THE METHODS OF MESA f- MASS DETERMINATION Approved: ra■•■•■■■■■■•■ Date Approved by Chairman /227 1 9. c-n iii ACKNOWLEDGMENTS I wish to express my sincerest thanks to Doctor L. D. Wyly for his valuable assistance in preparing this work. I would also like to thank my wife, Hilda, for her aid in proofreading the material. iv • TABLE OF CONTENTS CHAPTER PAGE I. INTRODUCTION 1 Statement of the Problem 1 Discussion of the Problem 3 Definition of Terms and Symbols Used . s 9 II. MESON HISTORY" 12 III. GENERAL APPARATUS EMPLOYED IN MESON MASS MEASURE- ENTS 19 IV. GENERAL Mi, THOD3 OF MEASURING RAN CE, CURVATURE, AND SPECIFIC IONIZATION 37 V. DIRECT METHODS OF MESON MASS DETERMINATION. 46 Elastic Collision 46 VI. INDIRECT METHODS OP MESON MASS DETERMINATION. 58 Range and Curvature 58 Momentum Loss 73 Ionization and Curvature 98 Method A: Primary Ionization of Slow Electrons and Curva- ture 98 Method B: Probable Ionization and Curvature 106 Ionization and Rahge 111 VII. PHOTOGRAPHIC PLATE METHODS OF MESON MASS DETERMI- NATION 119 Coulumb Scattering 125 Grain Counting 133 Magnetic Deflection 140 VIII. OTHR MSPHODS OF MESON MASS DETERMINATION . 152 TABLE OF CONTENTS (continued) ♦ CHAPTER PAGE Neutron-Proton Exchange Force . 152 Deflection in Combined Electric and Magnetic Fields 152 Disintegration 155 Photographic Technique 155 Cloud-Chamber Technique 160 Meso-States 162 IX. -
A Few Comments on the Top Quark Measurements Kirill Melnikov TTP
A few comments on the top quark measurements Kirill Melnikov TTP KIT Tuesday, November 17, 15 The outline I want to make a few comments concerning the top quark mass measurement at a hadron collider. These comments do not address specific measurements, or suggest particular improvements, or sharply point problems with existing analyses. What I am going to tell you are really just a few things that are related to top quark physics in general and the top quark mass measurement in particular, and that were bothering me for a while. I think those things are not discussed enough in the context of the top quark measurements. These things include: 1) Non-perturbative corrections to production cross sections and kinematic distributions as precision limiting factor for the determination of the top quark mass. 2) How does a finite life-time of the top quark impacts the non-perturbative corrections to top quark pair production ? 3) Top quark lifetimes are distributed exponentially; this means that there should be a few that live longer than the hadronization time. Are there mesons composed of the top quark and the light quark? How would one see them? Can one use those mesons to measure the top quark mass without an ambiguity? Tuesday, November 17, 15 Non-perturbative effects and the top quark mass Similar to the measurement of any observable at a hadron collider, extraction of the top quark mass is affected by non-perturbative effects. This is an issue that exists even if a short-distance mass definition for the top quark mass is chosen. -
Strange Hadron Production in Heavy Ion Collisions from SPS to RHIC
Strange hadron production in heavy ion collisions from SPS to RHIC C. Blume1 and C. Markert2 1Institut f¨ur Kernphysik, Johann Wolfgang Goethe-Universit¨at Frankfurt, Frankfurt, Germany. 2University of Texas at Austin, Austin, Texas 78712, USA. October 22, 2018 Abstract Strange particles have been a very important observable in the search for a deconfined state of strongly interacting matter, the quark-gluon plasma (QGP), which is expected to be formed in ultra-relativistic heavy ion collisions. We review the main experimental observations made at the Super Proton Synchrotron (SPS) at CERN, Geneva, and at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). The large amount of recently collected data allows for a comprehensive study of strangeness production as a function of energy and system size. We review results on yields, transverse mass and rapidity spectra, as well as elliptic flow. The measurements are interpreted in the context of various theoretical concepts and their implications are discussed. Of particular interest is the question whether strange particles are in any way sensitive to a partonic phase. Finally, a compilation of experimental data is provided. Contents 1 Introduction 3 1.1 Strangeness enhancement as QGP signal . ......... 4 2 Theoretical aspects 5 arXiv:1105.2798v2 [nucl-ex] 19 Aug 2011 2.1 Recentdevelopments ................................ ..... 5 2.2 Transportmodels ................................... .... 6 2.3 Statisticalmodels................................... .... 9 3 Experimental overview 12 3.1 Basicobservations .................................. .... 12 3.2 Experimentaltechniques . .. .. .. ...... 13 3.2.1 Chargedkaons .................................... 14 0 3.2.2 Hyperons and KS ................................... 15 3.2.3 Corrections ...................................... 17 1 4 Energy dependence 18 4.1 Strangeness enhancement at different energies .