Download or read book The Centrality Dependence of Flow in AU AU Collisions at 8 and 10 8 AGEV written by Peter-John Stanskas and published by . This book was released on 2001 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Anisotropic Flow Nu2 in Au Au Collisions at RHIC written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using the RQMD model, transverse momentum dependence of the anisotropic flow v2 for [pi], K, nucleon, [phi], and [lambda], are studied for Au + Au collisions at √s{sub NN} = 200 GeV. Both hydrodynamic hadron-mass hiragracy (hhmh) at low p{sub T} region and particle type dependence (baryon versus meson) at the intermediate p{sub T} region are reproduced with the model calculations although the model underpredicted the overall values of v2 by a factor of 2-3. As expected, when the rescatterings are turned off, all v2 becomes zero. The failure of the hadronic model in predicting the absolute values of hadron v2 clearly demonstrate the need of early dense partonic interaction in heavy-ion collisions at RHIC. At the intermediate p{sub T}, the hadron type dependence cold also be explained by the vacume hadronic cross sections within the frame of the model. The measurements of collective motion of hadrons from high-energy nuclear collisions can provide information on the dynamical equation of state information of the system [1, 2, 3]. Specifically, the strange and multi-strange hadron flow results have demonstrated the partonic collectivity [5] and the heavy-flavor flow will test the hypothesis of early thermalization in such collisions [4]. At RHIC, the measurements [6, 7] of elliptic flow v2 and nuclear modification factor r{sub AA} has lead to the conclusion that hadrons were formed via the coalescence/recombination of massive quarks [8, 9, 10]. This finding is directly related to the key issue in high-energy nuclear collisions such as deconfinement and chiral symmetry restoration. In addition, it also touched the important problem of hadronization process in high-energy collisions. Therefore a systematic study with different approaches becomes necessary. In this report, using a hadronic transport model UrQMD(v2.2)/RQMD(v2.4) [11, 12], we study the v2 of [pi], K, p, [phi], and [Lambda] from Au + Au collisions at 200 GeV. Properties of centrality dependent and freeze-out time dependent will be discussed. We try to answer some specific questions like how much the observed features can be reproduced by the hadronic model and why. In this approach, the vacumme cross sections are used for strong interactions. Unlike the treatment in most hydrodynamic calculations, the transition from strong interaction and free-steaming is determined by the local density and gradual. As we will discuss in the paper, the shortcoming of this method is lack of the partonic interactions which is important for the early dynamics in ultra-relativistic heavy ion collisions [13]. In order to take care of both partonic and hadronic interactions in high-energy nuclear collisions, a combination of hydrodynamic model for early stage (the perfect fluid stage) and hadronic transport model for later stage and freeze-out has been tried [14, 15].

Download or read book Intersections of Particle and Nuclear Physics written by Zohreh Parsa and published by American Inst. of Physics. This book was released on 2004-03-09 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this meeting, as with the seven previous conferences in this series, was to bring together particle and nuclear physicists to share scientific reports and discuss areas of research which overlap both their disciplines. Its relevance has steadily grown as the areas of overlap between particle and nuclear physics have increased. In addition, the success of the standard model has provided a common underpinning for both disciplines as well as similar fundamental goals. Indeed, Quantum Chromodynamics (QCD) has proven to be "the" theory of strong interactions. As such, it forms the basis for nuclear physics as well as high energy hadronic interactions. Topics included are: QCD spectroscopy and dynamics, relativistic heavy ions, QCD and nuclear structure, lepton-hadron and hadron-hadron scattering, heavy quark and heavy lepton physics, spin physics, nuclear and particle astrophysics, neutrinos, accelerators, facilities and detectors, as well as tests of fundamental symmetries.

Download or read book Strange Particle Production and Flow in 2 4 6 and 8 AGeV Au Au Collisions written by Paul Chung and published by . This book was released on 1999 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book DIFFRACTION 2002 Interpretation of the New Diffractive Phenomena in Quantum Chromodynamics and in the S Matrix Theory written by R. Fiore and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop, Alushta, Crimea, Ukraine, from 31 August to 6 September 2002

Download or read book Proceedings of the XXV DAE BRNS High Energy Physics HEP Symposium 2022 12 16 December Mohali India written by Satyajit Jena and published by Springer Nature. This book was released on with total page 1353 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Data Analysis Techniques for Physical Scientists written by Claude A. Pruneau and published by Cambridge University Press. This book was released on 2017-10-05 with total page 719 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive guide to data analysis techniques for physical scientists, providing a valuable resource for advanced undergraduate and graduate students, as well as seasoned researchers. The book begins with an extensive discussion of the foundational concepts and methods of probability and statistics under both the frequentist and Bayesian interpretations of probability. It next presents basic concepts and techniques used for measurements of particle production cross-sections, correlation functions, and particle identification. Much attention is devoted to notions of statistical and systematic errors, beginning with intuitive discussions and progressively introducing the more formal concepts of confidence intervals, credible range, and hypothesis testing. The book also includes an in-depth discussion of the methods used to unfold or correct data for instrumental effects associated with measurement and process noise as well as particle and event losses, before ending with a presentation of elementary Monte Carlo techniques.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2002 with total page 854 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Centrality Dependence of Identified Particle Elliptic Flow in Relativistic Heavy Ion Collisions at math mrow msqrt msub mi mi mrow mi N mi mi N mi mrow msub msqrt mo written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, elliptic flow (v2) values for identified particles at midrapidity in Au + Au collisions measured by the STAR experiment in the Beam Energy Scan at the Relativistic Heavy Ion Collider at √sNN = 7.7-62.4 GeV are presented for three centrality classes. The centrality dependence and the data at √sNN = 14.5 GeV are new. Except at the lowest beam energies, we observe a similar relative v2 baryon-meson splitting for all centrality classes which is in agreement within 15% with the number-of-constituent quark scaling. The larger v2 for most particles relative to antiparticles, already observed for minimum bias collisions, shows a clear centrality dependence, with the largest difference for the most central collisions. Also, the results are compared with a multiphase transport (AMPT) model and fit with a blast wave model.

Download or read book Elliptic Flow in Au Au Collisions at 200 GeV Per Nucleon Pair written by Carla Manuel Vale and published by . This book was released on 2004 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Relativistic Heavy Ion Collider (RHIC) has provided its experiments with the most energetic nucleus-nucleus collisions ever achieved in a laboratory. These collisions allow for the study of the properties of nuclear matter at very high temperature and energy density, and may uncover new forms of matter created under such conditions. This thesis presents measurements of the elliptic flow amplitude, v2, in Au+Au collisions at RHIC's top center of mass energy of 200 GeV per nucleon pair. Elliptic flow is interesting as a probe of the dynamical evolution of the system formed in the collision. The elliptic flow dependences on transverse momentum, centrality, and pseudorapidity were measured using data collected by the PHOBOS detector during the 2001 RHIC run. The reaction plane of the collision was determined using the multiplicity detector, and the azimuthal angles of tracks reconstructed in the spectrometer were then correlated with the found reaction plane. The v2 values grow almost linearly with transverse momentum, up to P[sub]T of approximately 1.5 GeV, saturating at about 14%. As a function of centrality, v2 is minimum for central events, as expected from geometry, and increases up to near 7% (for 0

Download or read book How And Where To Go Beyond The Standard Model Proceedings Of The International School Of Subnuclear Physics written by Antonino Zichichi and published by World Scientific. This book was released on 2007-03-27 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a collection of lectures given during the 42nd Course of the International School of Subnuclear Physics. The contributions cover the most recent advances in theoretical physics and the latest results from current experimental facilities.In line with one of the aims of the school, which is to encourage and promote young physicists to achieve recognition at an international level, the students' recognized for their research excellence were given the opportunity to publish their work in this volume. Their contributions are joined by those from many distinguished lecturers in the field from around the world.

Download or read book Intriguing Centrality Dependence of the Au Au Source Size at the AGS written by and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the main goals of high energy heavy ion physics is to establish the existence of a deconfined phase of nuclear matter--the quark-gluon plasma--at high temperatures or densities. One possible signature of such a phase transition, especially if it were first order, would be a larger source size or lifetime than a similar hadronic system. At current AGS energies, we attempt to form a quark- gluon plasma by achieving a high baryon density for a period of time in the center of the collision region. For a given density threshold, the size of this high density region should be a strong function of the impact parameter: the more central the event, the larger the high density region. Therefore, one possible signature of a quark-gluon plasma would be a sudden change in system lifetime or size as a function of the centrality of the collision. In this talk we present an intriguing effect which was not predicted for simple hadronic systems: a rapid increase of the HBT-measured source radius parameter for pion pairs with increasing centrality for Au-Au collisions at a beam momentum of 11.45 A GeV/c on a fixed target. Experience has shown, however, that we must be cautious in our interpretation. A complete understanding of the collision dynamics at a given energy must be built up from several measurements and new, but conventional, hadronic explanations must be considered for such unexpected effects. More study is needed, therefore, before any strong conclusions can be reached.

Download or read book Few body Problems in Physics written by Yupeng Yan and published by World Scientific. This book was released on 2007 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Asia-Pacific Conferences on Few-Body Problems in Physics tackle cover the various aspects of few-body systems in physics, with high caliber contributions from internationally renowned researchers. Readers will gain a clear picture of the latest developments in the field in both the theoretical and experimental sectors. The scope of these proceedings covers research in the following areas: three-body forces and few-nucleon dynamics, hadron structure and QCD; exotic hadrons and atoms; effective field theory in few-body physics; electromagnetic and weak processes in few-body systems; few-body dynamics in atoms, molecules, BoseOCoEinstein condensates and quantum dots; few-body approaches to unstable nuclei, nuclear astrophysics and nuclear clustering aspects; and hypernuclear physics."

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 Nuclear Physics in the 21st Century written by International Union of Pure and Applied Physics and published by American Institute of Physics. This book was released on 2002-04-09 with total page 1136 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains papers based on all the oral presentations delivered at the INPC 2001. Topics include: nuclear structure, neutrino physics, nuclear astrophysics, nuclear reaction dynamics, high energy nuclear physics, and applications of nuclear science.

Download or read book The CBM Physics Book written by Bengt Friman and published by Springer Science & Business Media. This book was released on 2011-03-10 with total page 973 pages. Available in PDF, EPUB and Kindle. Book excerpt: This exhaustive survey is the result of a four year effort by many leading researchers in the field to produce both a readable introduction and a yardstick for the many upcoming experiments using heavy ion collisions to examine the properties of nuclear matter. The books falls naturally into five large parts, first examining the bulk properties of strongly interacting matter, including its equation of state and phase structure. Part II discusses elementary hadronic excitations of nuclear matter, Part III addresses the concepts and models regarding the space-time dynamics of nuclear collision experiments, Part IV collects the observables from past and current high-energy heavy-ion facilities in the context of the theoretical predictions specific to compressed baryonic matter. Part V finally gives a brief description of the experimental concepts. The book explicitly addresses everyone working or planning to enter the field of high-energy nuclear physics.

Download or read book Advances in Nuclear Dynamics 3 written by Wolfgang Bauer and published by Springer Science & Business Media. This book was released on 1997 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a February 1997 workshop bringing together experimental and theoretical expertise from all areas of the study of nuclear dynamics. Phase transitions in nuclear collisions is a major topic. Other subjects include research at the CERN SPS, nuclear temperature measurement and secondary d