High Energy Heavy Ion Experiments
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The First Few Microseconds
the first few MICROSSECONDSECONDS In recent experiments, physicists have replicated conditions of the infant universe— with startling results BY MICHAEL RIORDAN AND WILLIAM A. ZAJC or the past fi ve years, hundreds of scientists have been using a pow- erful new atom smasher at Brookhaven National Laboratory on Long Island to mimic conditions that existed at the birth of the uni- verse. Called the Relativistic Heavy Ion Collider (RHIC, pro- nounced “rick”), it clashes two opposing beams of gold nuclei trav- Feling at nearly the speed of light. The resulting collisions between pairs of these atomic nuclei generate exceedingly hot, dense bursts of matter and en- ergy to simulate what happened during the fi rst few microseconds of the big bang. These brief “mini bangs” give physicists a ringside seat on some of the earliest moments of creation. During those early moments, matter was an ultrahot, superdense brew of particles called quarks and gluons rushing hither and thither and crashing willy-nilly into one another. A sprinkling of electrons, photons and other light elementary particles seasoned the soup. This mixture had a temperature in the trillions of degrees, more than 100,000 times hotter than the sun’s core. But the temperature plummeted as the cosmos expanded, just like an or- dinary gas cools today when it expands rapidly. The quarks and gluons slowed down so much that some of them could begin sticking together briefl y. After nearly 10 microseconds had elapsed, the quarks and gluons became shackled together by strong forces between them, locked up permanently within pro- tons, neutrons and other strongly interacting particles that physicists collec- tively call “hadrons.” Such an abrupt change in the properties of a material is called a phase transition (like liquid water freezing into ice). -
Charged Kaon Ratios and Yields Measured with the STAR Detector at the Relativistic Heavy Ion
Charged Kaon Ratios and Yields Measured with the STAR Detector at the Relativistic Heavy Ion Collider By C.L. Kunz B.S. Chemistry, McPherson College, 1997 Submitted in Partial Fulfillment of the Requirement for the Degree of Doctor of Philosophy Department of Chemistry Carnegie Mellon University Pittsburgh, Pennsylvania 15213 September 2003 This thesis is dedicated to my parents for their guidance and support. They have long been two of my best friends. Without them, I would not be here. ii © Copyright 2003 by Christopher Lee Kunz All Rights Reserved iii Table of Contents TABLE OF CONTENTS ...............................................................................................IV LIST OF TABLES ........................................................................................................ VII LIST OF FIGURES .....................................................................................................VIII ACKNOWLEDGMENTS ............................................................................................... X ABSTRACT................................................................................................................... XII SECTION 1........................................................................................................................ 1 1.1 INTRODUCTION .......................................................................................................... 1 SECTION 2....................................................................................................................... -
Exotic Antimatter Detected at RHIC Denes Molnar the Goal of Gozar’Sgoaltheof Research Is Eluci Help Maydiscovery the Discovery Experimental “This on March 4,2010
the Vol. 64B - No. 11 ulletin April 2, 2010 Exotic Antimatter Detected at RHIC Scientists report discovery of heaviest known antinucleus — the first D0680809 containing an anti-strange quark — laying the first stake in a new frontier of physics An international team of scien- known as “strangeness,” which tists studying high-energy colli- depends on the presence of sions of gold ions at the Relativ- strange quarks. Nuclei contain- Joseph Rubino istic Heavy Ion Collider (RHIC), ing one or more strange quarks a 2.4-mile-circumference particle are called hypernuclei. ‘Communicating accelerator located at BNL, has For all ordinary matter, with Science’ published evidence of the most no strange quarks, the strange- massive antinucleus discovered ness value is zero and the chart Alan Alda to date. The new antinucleus, is flat. Hypernuclei appear above discovered at RHIC’s STAR detec- the plane of the chart. The new To Give Talk, 4/9 tor, is a negatively charged state discovery of strange antimatter At 9 a.m. on April 9 in Berkner of antimatter containing an with an antistrange quark (an Hall, Lab Director Sam Aronson antiproton, an antineutron, and antihypernucleus) marks the first Michael Herbert will welcome Alan Alda, the ac- an anti-Lambda particle. It is also entry below the plane. claimed actor and host of PBS’ the first antinucleus containing This study of the new antihy- “Scientific American Frontiers,” an anti-strange quark. The results pernucleus also yields a valuable and Howie Schneider, Dean of were published online by Science sample of normal hypernuclei, Express on March 4, 2010. -
The Mar (E) K of QGP: Strangeness
The Mar(e)k of QGP: Strangeness∗ Jan Rafelski Department of Physics, The University of Arizona Tucson, AZ 85721, USA Strangeness signature of of quark-gluon plasma (QGP) is central to the exploration of baryon-dense matter: the search for the critical point and onset of deconfinement. I report on the discovery of QGP by means of strangeness: The key historical figures and their roles in this quest are introduced and the experimental results obtained are discussed. The im- portant role of antihyperons is emphasized. The statistical hadronization model, and sudden hadronization are described. Results of present day data analysis: strangeness and entropy content of a large fireball, and the universal hadronization condition describing key features of all explored collision systems are presented. PACS numbers: 25.75.-qRelativistic heavy-ion collisions 12.38.MhQuark-gluon plasma 24.10.PaThermal and statistical models 1. Introduction The introduction in 1964 of the new quark paradigm [1] `happened' nearly in parallel to the rise of the thermal model of hadron production pre- cipitated by Hagedorn's invention of the statistical bootstrap model, for a review of Hagedorn's work, see Ref. [2]. The paradigm of quarks explained a large number of properties of elementary particles, allowing at the time one prediction, a new particle, the triple-strange Ω−(sss). On the other hand Hagedorn was following fragmentary experimental data on particle produc- tion; these data were not in agreement with the rudimentary statistical arXiv:1701.00296v2 [hep-ph] 6 Feb 2017 particle production models proposed by Koppe [3] and Fermi [4]. Hage- dorn's work is a classic example of a discovery case where theory preceded experiment, focusing the direction of future experimental work. -
Before Matter As We Know It Emerged, the Universe Was Filled with The
Cambridge University Press 0521385369 - Hadrons and Quark–Gluon Plasma Jean Letessier and Johann Rafelski Frontmatter More information HADRONS AND QUARK–GLUON PLASMA Before matter as we know it emerged, the universe was filled with the primordial state of hadronic matter called quark–gluon plasma. This hot soup of quarks and gluons is effectively an inescapable consequence of our current knowledge about the fundamental hadronic interactions: quantum chromodynamics. This book covers the ongoing search to verify the prediction experimentally and discusses the physical properties of this novel form of matter. It provides an accessible introduction to the recent developments in this interdisciplinary field, covering the basics as well as more advanced material. It begins with an overview of the subject, followed by discussion of experimental methods and results. The second half of the book covers hadronic matter in confined and deconfined form, and strangeness as a signature of the quark–gluon phase. A firm background in quantum mechanics, special relativity, and statistical physics is assumed, as well as some familiarity with particle and nuclear physics. However, the essential introductory elements from these fields are presented as needed. This text is suitable as an introduction for graduate students, as well as pro- viding a valuable reference for researchers already working in this and related fields. JEAN LETESSIER has been CNRS researcher at the University of Paris since 1978. Prior to that he worked at the Institut de Physique Nucleaire, Orsay, where he wrote his thesis on hyperon–nucleon interaction in 1970, under the direction of Professor R. Vinh Mau, and was a teaching assistant at the University of Bordeaux. -
Azimuthal Dependence of Pion Interferometry in Au + Au Collisions at a Center of Mass Energy of 130Agev
Azimuthal Dependence of Pion Interferometry in Au + Au Collisions at a Center of Mass Energy of 130AGeV DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Randall C. Wells, B.S., M.S. ***** The Ohio State University 2002 Dissertation Committee: Approved by Michael A. Lisa, Adviser Richard Furnstahl Adviser Thomas Humanic Department of Physics Douglas Schumacher UMI Number: 3081976 ________________________________________________________ UMI Microform 3081976 Copyright 2003 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ____________________________________________________________ ProQuest Information and Learning Company 300 North Zeeb Road PO Box 1346 Ann Arbor, MI 48106-1346 ABSTRACT The study of two-pion Bose–Einstein correlations provides a tool to extract both spatial and dynamic information regarding the freeze–out configuration of the emis- sion region created in heavy ion collisions. Noncentral heavy ion collisions are inher- ently spatially and dynamically anisotropic. The study of such collisions through the 2 φ dependence of the HBT radii, Rij, relative to the event plane allows one to observe the source from all angles, leading to a richer description of the interplay between geometry and dynamics. The initial heavy ion running of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory provided Au + Au collisions at 130GeV .Thefocus of the heavy ion program at RHIC is the search for a new state of strongly interact- ing matter, the quark gluon plasma (QGP). STAR is a large acceptance detector at RHIC with azimuthal symmetry, allowing the study of a large variety of observables on an event–by–event basis to provide a better characterization of the freeze–out con- ditions. -
People and Things
People and things cesses, such as those of Interest plore the low energy regime of to astrophysicists. Experiments at quantum chromodynamics (QCD), 20 Tesla for sale PSI have provided important limits the candidate field theory of quark on the masses of the electron-type interactions and, with the electro- An Oxford Instruments supercon• and muon-type neutrinos. weak picture, one of the twin fa• ducting solenoid magnet which has When the muon does decay, it cets of Standard Model formalism. exceeded 20 Tesla is now available goes most of the time into an elec• Muon capture on hydrogen has commercially. Although higher tron and a pair of suitably labelled been a challenge to experimental• fields have been achieved with lab• neutrinos. The strength of this de• ists; the process is rare and is oratory magnets, this is said to be cay is one of the basic input para• masked by atomic and molecular the most powerful such magnet on meters of the electroweak picture effects, but a new generation of the market. within the Standard Model. Careful studies is planned at meson facto• Operating at 2.15 K, the 32 mm analysis of the spins of the muon ries. diameter coil uses niobium-titanium and the electron in these decays, Atomic and molecular physics wire for the outer windings with together with studies of the scat• again emerges as a dominant the inner sections of niobium-tin tering of muon-type neutrinos off theme in the interaction of muons optimized for high field use. Oxford electrons, could help look beyond with hydrogen isotopes - deuter• Instruments is at Eynsham, Oxford, the Standard Model. -
From Strangeness Enhancement to Quark-Gluon Plasma Discovery∗
August 29, 2017 0:23 ws-rv961x669 Book Title KMR_ForWalterWSHess4B page 1 From Strangeness Enhancement to Quark-Gluon Plasma Discovery∗ Peter Koch1, Berndt M¨uller2 and Johann Rafelski3 1Bitfabrik GmbH & Co. KG, D-63110 Rodgau, Germany 2Department of Physics, Duke University, Durham, NC 27708, USA 3Department of Physics, The University of Arizona, Tucson, AZ 85721, USA This is a short survey of signatures and characteristics of the quark-gluon plasma in the light of experimental results that have been obtained over the past three decades. In particular, we present an in-depth discussion of the strangeness ob- servable, including a chronology of the experimental effort to detect QGP at CERN-SPS, BNL-RHIC, and CERN-LHC. ∗Dedicated to our mentor Walter Greiner; to be published in the memorial volume edited by Peter O. Hess. 1. Introduction Just fifteen years after the coincident creation in 1964 of two great ideas governing the strong interactions | quarks and the Hagedorn temperature TH | these two concepts merged, giving birth to a new discipline, the physics of the novel fifth state of matter, the quark-gluon plasma (QGP). Today there is consensus that QGP filled the cosmos during the first 20 µs after the Big-Bang. For three decades laboratory experiments at the European Center for Particle Physics (CERN) and Brookhaven National Laboratory (BNL) have been exploring this primordial phase of matter colliding nuclei at relativistic energies. As the ideas about QGP formation in relativistic heavy ion collisions matured a practical challenge emerged: How can the locally color deconfined QGP state be distinguished from a gas of confined hadrons? In the period 1979{86 the strangeness signature of QGP was developed for this purpose, with our 1986 review1 in essence arXiv:1708.08115v1 [nucl-th] 27 Aug 2017 completing the theoretical foundations. -
People and Things
People and things cesses, such as those of Interest plore the low energy regime of to astrophysicists. Experiments at quantum chromodynamics (QCD), 20 Tesla for sale PSI have provided important limits the candidate field theory of quark on the masses of the electron-type interactions and, with the electro- An Oxford Instruments supercon• and muon-type neutrinos. weak picture, one of the twin fa• ducting solenoid magnet which has When the muon does decay, it cets of Standard Model formalism. exceeded 20 Tesla is now available goes most of the time into an elec• Muon capture on hydrogen has commercially. Although higher tron and a pair of suitably labelled been a challenge to experimental• fields have been achieved with lab• neutrinos. The strength of this de• ists; the process is rare and is oratory magnets, this is said to be cay is one of the basic input para• masked by atomic and molecular the most powerful such magnet on meters of the electroweak picture effects, but a new generation of the market. within the Standard Model. Careful studies is planned at meson facto• Operating at 2.15 K, the 32 mm analysis of the spins of the muon ries. diameter coil uses niobium-titanium and the electron in these decays, Atomic and molecular physics wire for the outer windings with together with studies of the scat• again emerges as a dominant the inner sections of niobium-tin tering of muon-type neutrinos off theme in the interaction of muons optimized for high field use. Oxford electrons, could help look beyond with hydrogen isotopes - deuter• Instruments is at Eynsham, Oxford, the Standard Model. -
QM04 Strangeness Report
Strangeness Report Federico Antinori Istituto Nazionale di Fisica Nucleare, Padova, Italy Abstract The paper provides a short report on strangeness production in ultrarelativistic nucleus- nucleus collision, with the main stress on strange particle abundances. 1. Introduction Strangeness is a vast subject. The amount of measurements relative to strange particles is huge. A major reason why strangeness is so interesting is that the strange flavour is not present at the beginning of the collision; it has to be produced by “cooking” in the reaction. The study of strangeness production, therefore, provides us with essential information about the physical environment created in nucleus-nucleus collisions. The primary piece of information is just how much strangeness is produced, i.e. the strangeness abundance. In these proceedings, many measurements involving strange particles are covered in other review papers [1-5]; I will concentrate mainly on the abundance of strange particles: particle yields and particle ratios. Our present knowledge on the pattern of enhancement of the production yields of strange and multi-strange particles in nucleus-nucleus collisions is summarised in section 2. Section 3 contains a brief discussion of the status of the comparison between experimental data and conventional hadronic transport models. Thermal equilibrium fits are discussed in section 4, while the experimental observations which may point to physics beyond equilibrium thermodynamics are discussed, rather speculatively, in section 5. The Φ mysteries are treated separately in section 6. Finally, I offer my conclusions in section 7. My oral presentation at the Quark Matter 2004 Conference also contained a selection of results on spectra from RHIC which could not find their way into the proceedings for reasons of space. -
Study Quark Gluon Plasma by Particle Correlations In
STUDY QUARK GLUON PLASMA BY PARTICLE CORRELATIONS IN HEAVY ION COLLISIONS A Dissertation Submitted to the Faculty of Purdue University by Li Yi In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2014 Purdue University West Lafayette, Indiana ii To my parents. iii ACKNOWLEDGMENTS On the journey to my doctoral degree, I have been blessed by many individuals, totaling more than can be listed here. First and foremost, I would like to thank my advisor Prof. Fuqiang Wang for his guidance and support over years with my research and my career. Prof. Wang guided me through the adventure of research with his inspiring ideas, patience in mentoring, prudent attitude towards data analysis, and critical feedback on the results. I would like to thank Prof. Wei Xie, Prof. Andrew Hirsch, Prof. Rolf Scharenberg and Prof. Brijish Srivastava for their helpful advices and discussions during the regular group meetings. I also would like to thank Prof. Denes Molnar for his valuable and fun discussions through his heavy-ion course and in regards to my thesis. I also would like to thank Prof. Matthew L. Lister to serving on my thesis committee. I would like to express my thanks to my fellow graduate students in heavy-ion group for their daily discussions: Tyler Browning, Liang He, Xin Li, Kun Jiang, Kurt Jung, Michael Skoby, Deke Sun, Jian Sun, Quan Wang. I received much encour- agement and help from Joshua Konzer from the beginning of my studies through when he graduated. I feel grateful to David Garand for providing feedback on my presentations and paper works. -
Investigating Parton Energy Loss in the Quark-Gluon Plasma with Jet-Hadron Correlations and Jet Azimuthal Anisotropy at STAR
Investigating Parton Energy Loss in the Quark-Gluon Plasma with Jet-hadron Correlations and Jet Azimuthal Anisotropy at STAR A Dissertation Presented to the Faculty of the Graduate School of Yale University in Candidacy for the Degree of Doctor of Philosophy by Alice Elisabeth Ohlson Dissertation Director: John Harris December 2013 Copyright c 2013 by Alice Elisabeth Ohlson All rights reserved. ii Abstract Investigating Parton Energy Loss in the Quark-Gluon Plasma with Jet-hadron Correlations and Jet Azimuthal Anisotropy at STAR Alice Elisabeth Ohlson 2013 In high-energy collisions of gold nuclei at the Relativistic Heavy Ion Collider (RHIC) and of lead nuclei at the Large Hadron Collider (LHC), a new state of matter known as the Quark-Gluon Plasma (QGP) is formed. This strongly-coupled, deconfined state of quarks and gluons represents the high energy-density limit of quantum chro- modynamics. The QGP can be probed by high-momentum quarks and gluons (collec- tively known as partons) that are produced in hard scatterings early in the collision. The partons traverse the QGP and fragment into collimated “jets” of hadrons. Stud- ies of parton energy loss within the QGP, or medium-induced jet quenching, can lead to insights into the interactions between a colored probe (a parton) and the colored medium (the QGP). Two analyses of jet quenching in relativistic heavy ion collisions are presented here. In the jet-hadron analysis, the distributions of charged hadrons with respect to the axis of a reconstructed jet are investigated as a function of azimuthal angle and transverse momentum (pT). It is shown that jets that traverse the QGP are softer (consisting of fewer high-pT fragments and more low-pT constituents) than jets in p+p collisions.