Download or read book Neutral Strange Particle Production in Ultra Relativistic Heavy Ion Collisions at square Root Of superior S NN written by Matthew Allan Charles Lamont and published by . This book was released on 2002 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phenomenology of Ultra relativistic Heavy ion Collisions written by and published by World Scientific. This book was released on 2010 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to the main ideas used in the physics of ultra-realistic heavy-ion collisions, this book covers topics such as hot and dense matter and the formation of the quark-gluon plasma in present and future heavy-ion experiments

Download or read book Strangeness Production in Heavy Ion Collisions written by and published by . This book was released on 2002 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of strange particle production in heavy ion collisions at ultrarelativistic energies is presented. The particle yields and ratios from SPS and RHIC are discussed in view of the newest developments in understanding collision dynamics, and in view of their role in the search for a quark gluon plasma. A strangeness enhancement, most notably observed in CERN Pb-beam results, shows a remarkable two fold global enhancement with a much larger effect seen in the case of multistrange baryons. Hadronic models did fail to explain this pattern. At RHIC energy strangeness assumes a different role, since temperatures are higher and the central rapidity region almost baryon-free. An intriguing question: ''Did RHIC change the way we understand strangeness production in heavy ion collisions?'' is discussed.

Download or read book Introduction to Relativistic Heavy Ion Physics written by Jerzy Bartke and published by World Scientific. This book was released on 2009 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book attempts to cover the fascinating field of physics of relativistic heavy ions, mainly from the experimentalist's point of view. After the introductory chapter on quantum chromodynamics, basic properties of atomic nuclei, sources of relativistic nuclei, and typical detector set-ups are described in three subsequent chapters. Experimental facts on collisions of relativistic heavy ions are systematically presented in 15 consecutive chapters, starting from the simplest features like cross sections, multiplicities, and spectra of secondary particles and going to more involved characteristics like correlations, various relatively rare processes, and newly discovered features: collective flow, high pT suppression and jet quenching. Some entirely new topics are included, such as the difference between neutron and proton radii in nuclei, heavy hypernuclei, and electromagnetic effects on secondary particle spectra.Phenomenological approaches and related simple models are discussed in parallel with the presentation of experimental data. Near the end of the book, recent ideas about the new state of matter created in collisions of ultrarelativistic nuclei are discussed. In the final chapter, some predictions are given for nuclear collisions in the Large Hadron Collider (LHC), now in construction at the site of the European Organization for Nuclear Research (CERN), Geneva. Finally, the appendix gives us basic notions of relativistic kinematics, and lists the main international conferences related to this field. A concise reference book on physics of relativistic heavy ions, it shows the present status of this field.

Download or read book First Moment of Azimuthal Anisotropy in Au Au Collisions from the Beam Energy Scan at the Relativistic Heavy Ion Collider written by Prashanth Shanmuganathan and published by . This book was released on 2016 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excited nuclear matter at high temperature and density results in the creation of a new state of matter called Quark Gluon Plasma (QGP). It is believed that the Universe was in the QGP state a few millionths of a second after the Big Bang. A QGP can be experimentally created for a very brief time by colliding heavy nuclei, such as gold, at ultra-relativistic energies. The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory consists of two circular rings, 3.8 km in circumference, which can accelerate heavy nuclei in two counter-rotating beams to nearly the speed of light (up to 100 GeV per beam). STAR (Solenoidal Tracker At RHIC) is one of two large detectors at the RHIC facility, and was constructed and is operated by a large international collaboration made up of more than 500 scientists from 56 institutions in 12 countries. STAR has been taking data from heavy ion collisions since the year 2000. An important component of the physics effort of the STAR collaboration is the Beam Energy Scan (BES), designed to study the properties of the Quantum Chromodynamics (QCD) phase diagram in the regions where a first-order phase transition and a critical point may exist. Phase-I of the BES program took data in 2010, 2011 and 2014, using Au+Au collisions at a center-of-mass energy per nucleon pair of 7.7, 11.5, 14.5, 19.6, 27 and 39 GeV. It is by now considered a well-established fact that the QGP phase exists. However, all evidence so far indicates that there is a smooth crossover when normal hadronic matter becomes QGP and vice versa in collisions at the top energy of RHIC (and likewise at the Large Hadron Collider at the CERN laboratory in Switzerland). At these very high energies, the net density of baryons like nucleons is quite low, since there are almost equal abundances of baryons and antibaryons. It is known that net-baryon compression increases as the beam energy is lowered below a few tens of GeV. Of course, if the beam energy is too low, then the QGP phase cannot be produced at all, so it has been proposed that there is an optimum beam energy, so far unknown, where phenomena like a first-order phase transition and a critical point might be observed. On the other hand, there also exists the possibility that a smooth crossover to QGP occurs throughout the applicable region of the QCD phase diagram. Experiments are needed to resolve these questions. In this dissertation, I focus on one of the main goals of the BES program, which is to search for a possible first-order phase transition from hadronic matter to QGP and back again, using measurements of azimuthal anisotropy. The momentum-space azimuthal anisotropy of the final-state particles from collisions can be expressed in Fourier harmonics. The first harmonic coefficient is called directed flow, and reflects the strength of the collective sideward motion, relative to the beam direction, of the particles. Models tell us that directed flow is imparted during the very early stage of a collision and is not much altered during subsequent stages of the collision. Thus directed flow can provide information about the early stages when the QGP phase exists for a short time. A subset of hydrodynamic and nuclear transport model calculations with the assumption of a first-order phase transition show a prominent dip in the directed flow versus beam energy. I present directed flow and its slope with respect to rapidity, for identified particle types, namely lambda, anti-lambda and kaons as a function of beam energy for central, intermediate and peripheral collisions. The production threshold of neutral strange particles requires them to be created earlier, and these particles have relatively long mean free path. Thus these particles may probe the QGP at earlier times. In addition, new Lambda measurements can provide more insight about baryon number transported to the midrapidity region by stopping process of the nuclear collision. It is noteworthy that net-baryon density (equivalent to baryon chemical potential) depends not only on beam energy but also on collision centrality. The centrality dependence of directed flow and its slope are also studied for all BES energies for nine identified particle types, lambda, anti-lambda, neutral kaons, charged kaons, protons, anti-protons, and charged pions. These detailed results for many particle species, where both centrality and beam energy are varied over a wide range, strongly constrain models. The measurements summarized above pave the way for a new round of model refinements and subsequent comparisons with data. If the latter does not lead to a clear conclusion, the BES Phase-II program will take data in 2019 and 2020 with an upgraded STAR detector with wider acceptance, greatly improved statistics, and will extend measurements to new energy points.

Download or read book Introduction to Relativistic Heavy Ion Collisions written by L. P. Csernai and published by . This book was released on 1994-05-10 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Relativistic Heavy Ion Collisions László P. Csernai University of Bergen, Norway Written for postgraduates and advanced undergraduates in physics, this clear and concise work covers a wide range of subjects from intermediate to ultra-relativistic energies, thus providing an introductory overview of heavy ion physics. The reader is introduced to essential principles in heavy ion physics through a variety of questions, with answers, of varying difficulty. This timely text is based on a series of well received lectures given by Professor L. Csernai at the University of Minnesota, and the University of Bergen, where the author is based.

Download or read book Strangeness Production and Strange V0 Charged Hadron Correlation in Heavy ion Collisions written by Feng Zhao and published by . This book was released on 2014 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: In relativistic heavy-ion collisions, experimental evidence indicates that a new form of matter with de-confined quarks and gluons named the Quark-Gluon Plasma(QGP) has been created. The Relativistic Heavy Ion Collider (RHIC) provides a unique opportunity to study the QGP matter. Strange hadron production is believed to be sensitive to parton dynamics in heavy-ion collisions. In particular, the strange quark production rate and its subsequent evolution in the dense partonic medium depend on the beam energy and the net baryon density. The productions of K0s, [Lambda], [Xi], [Omega] at mid-rapidity from Au+Au collisions at the beam energies of 7.7, 11.5, 19.6, 27, and 39GeV from the RHIC Beam Energy Scan Program are measured. We investigate the strangeness enhancement and ratios of anti-baryon to baryon yields as a function of beam energy at RHIC. Nuclear modification factors and ratios of baryon to meson yields are also studied. Implications on collision dynamics due to the increase in the baryon chemical potential at low beam energy and constraints on chemical freeze-out parameters will also be discussed in this thesis. Parity-odd domains are theorized to form inside the QGP and to cause electric charge separation with respect to the reaction plane in the relativistic heavy-ion collisions via the Chiral Magnetic Effect (CME). Such charge separation has been studied at RHIC and LHC via the difference in two particle correlation between the opposite charge and same charge hadrons. The [Lambda](Lambda) and K0s particles are charge-neutral, and are supposed to bear no charge separation effects due to CME. We study the correlation between the neutral particle and charged hadron to investigate background for charged hadron correlation. In addition, the large angular momentum in heavy-ion collisions is predicted to lead to the Chiral Vortical Effect (CVE) which induces a baryon number separation, in analogy with the electric charge separation caused by CME. We carried out a study of [Lambda] - p correlations to search for the CVE. We present measurements of correlations for [Lambda] - h±, K0s - p, [Lambda] - p, in Au+Au collisions at 39GeV and 200GeV, to study the electric charge and baryon number separations across the reaction plane.

Download or read book Relativistic Heavy ion Collisions written by Rudolph C. Hwa and published by CRC Press. This book was released on 1990 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers of the June 1989 meeting in Beijing by the China Center of Advanced Science and Technology. This small book covers nucleus- nucleus collisions, states of the vacuum, and highly relativistic heavy ions in the experimental realm. Theoretical papers deal with quark-gluon plasma, and relativistic heavy ion collisions. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book Particle production Mechanism in Relativistic Heavy ion Collisions written by and published by . This book was released on 1994 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss the production of particles in relativistic heavy-ion collisions through the mechanism of massive bremsstrahlung, in which massive mesons are emitted during rapid nucleon acceleration. This mechanism is described within the framework of classical hadrodynamics for extended nucleons, corresponding to nucleons of finite size interacting with massive meson fields. This new theory provides a natural covariant microscopic approach to relativistic heavy-ion collisions that includes automatically spacetime nonlocality and retardation, nonequilibrium phenomena, interactions among all nucleons, and particle production. Inclusion of the finite nucleon size cures the difficulties with preacceleration and runaway solutions that have plagued the classical theory of self-interacting point particles. For the soft reactions that dominate nucleon-nucleon collisions, a significant fraction of the incident center-of-mass energy is radiated through massive bremsstrahlung. In the present version of the theory, this radiated energy is in the form of neutral scalar ([sigma]) and neutral vector ([omega]) mesons, which subsequently decay primarily into pions with some photons also. Additional meson fields that are known to be important from nucleon-nucleon scattering experiments should be incorporated in the future, in which case the radiated energy would also contain isovector pseudoscalar ([pi], [pi]−, [pi]°), isovector scalar ([delta]+, [delta]−, [delta]°), isovector vector ([rho]+, [rho]−, [rho]°), and neutral pseudoscalar ([eta]) mesons.

Download or read book Strangeness Production in Relativistic Nuclear Collisions written by and published by . This book was released on 1998 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of strange particle production in heavy ion collisions from AGS to SPS energies is presented. Implications of the newest developments in understanding the collision dynamics and the role of strange particle production in the search for a new phase of matter, in both experimental and theoretical sectors, are discussed.

Download or read book RELATIVISTIC HEAVY ION PHYSICS written by and published by . This book was released on 2002 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-energy collisions of heavy ions provide a means to study QCD in a regime of high parton density, and may provide insight into its phme structure. Results from the four experiments at RHIC (BRAHMS, PHENIX, PHOBOS and STAR) are presented, and placed in context with the lower energy data from the AGS and SPS accelerators. The focus is on the insights these measurements provide into the time history of the collision process. Taken together, the data point to the creation of a deconfined state of matter that forms quickly, expands rapidly and freezes out suddenly. With the new RHIC data, systematic data now exists for heavy ion collisions as a function of (square root)s over several orders of magnitude and as a function of impact parameter. These data test the interplay between hard and soft processes in a large-volume system where nucleons are struck multiple times. The data is consistent with creating a deconfined state (jet quenching) that forms quickly (saturation models), expands rapidly (radial and elliptic flow) and freezes out suddenly (single freezeout and blast wave fits). There are also intriguing connections with particle production in elementary systems, which point to the role of the energy available for particle production on the features of the final state. Many in this field are optimistic that the careful understanding of this experimental data may lead t o the theoretical breakthroughs that will connect these complex systems to the fundamental lattice predict ions.

Download or read book UNIVERSAL BEHAVIOR OF CHARGED PARTICLE PRODUCTION IN HEAVY ION COLLISIONS written by and published by . This book was released on 2002 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at (square root)(s{sub NN}) = 19.6, 130 and 200 GeV. Two observations indicate universal behavior of charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/{bar p}p and ee− data. Nch/N{sub part}/2 in nuclear collisions at high energy scales with (square root)s in a similar way as N{sub ch} in ee− collisions and has a very weak centrality dependence. These features may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions.

Download or read book Experimental Studies of Particle Production in Ultra relativistic Heavy Ion Collisions written by Pål Nilsson and published by . This book was released on 2001 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Particle Production in Relativistic Heavy Ion Collisions written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Relativistic Heavy Particle Collision Theory written by Derrick S.F. Crothers and published by Springer Science & Business Media. This book was released on 2000-09-30 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: If a heavy particle ion (atom, molecule, muon) collides with another in the gas phase at speeds approaching the speed of light, the time-dependent Dirac equation equation must be used for its description, including quantum electro-dynamic, special relativity and magnetic coupling effects. In this book we study one electron in the variety of rearrangement collisions: radiative and non-radiative capture, ionization, capture by pair (one electron, one positron) production and antihydrogen production. Our relativistic continuum distorted-wave theory accounts extremely well for the simultaneous behaviour of the electron with respect to the nuclear charges of the projectile and the target. This is the first book developed in this subject. Containing many diagrams and tables, and fully referenced, it goes beyond chapters in previous books. The relativistic continuum distorted-wave theory developed by the authors group, is shown to be fully Hermitean. Detailed mathematics are provided in nine appendices.

Download or read book Relative Yields of Antiparticles to Particles in Au Au Collisions at 130 and 200 GeV Per Nucleon Pair written by Kristján Herlache Gulbrandsen and published by . This book was released on 2004 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Au+Au collisions at [square root of] [superscript]s nn = 130 and 200 GeV at the Relativistic Heavy Ion Collider have opened a new energy regime for studying nucleus-nucleus collisions. A search for the formation of a phase of matter in which quarks and gluons interact strongly over an extended deconfined volume is of primary importance. The PHOBOS detector was constructed to measure many observables at RHIC. The primary subsystem used in this analysis is the PHOBOS spectrometer. The spectrometer is a multiplane silicon pad detector which detects particles traversing its pads as they propagate through a strong magnetic field. The hit positions are used along with energy loss information in the silicon pads to determine both the momentum and velocity of the particles, allowing for the identification of the particle species. One of the most basic pieces of information to be determined is the baryochemical potential of the system. This information has been determined through the measurement of the relative yields of antiparticles to particles in RHIC collisions ... These values are compared to model predictions and are used to evaluate the contribution of baryon transport relative to particle production in determining the yields of baryon at midrapidity in central Au+Au collisions at RHIC energies.

Download or read book UNIVERSAL BEHAVIOR OF CHARGED PARTICLE PRODUCTION IN HEAVY ION COLLISIONS AT RHIC ENERGIES written by and published by . This book was released on 2002 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at (square root)(s{sub NN}) = 19.6, 130 and 200 GeV. Two observations indicate universal behavior of charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/{bar p}p and ee− data. N{sub ch}/N{sub part}/2 in nuclear collisions at high energy scales with (square root)s in a similar way as N{sub ch} in ee− collisions and has a very weak centrality dependence. These features may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions.