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]

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]
Author:
Publisher:
Total Pages:
Release: 2016
Genre:
ISBN:

Download 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] Book in PDF, Epub and Kindle

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.

Anisotropic Flow Nu2 in Au + Au Collisions at RHIC.

Anisotropic Flow Nu2 in Au + Au Collisions at RHIC.
Author:
Publisher:
Total Pages:
Release: 2005
Genre:
ISBN:

Download Anisotropic Flow Nu2 in Au + Au Collisions at RHIC. Book in PDF, Epub and Kindle

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].

Properties of QCD Matter at High Baryon Density

Properties of QCD Matter at High Baryon Density
Author: Xiaofeng Luo
Publisher: Springer Nature
Total Pages: 294
Release: 2023-01-01
Genre: Science
ISBN: 9811944415

Download Properties of QCD Matter at High Baryon Density Book in PDF, Epub and Kindle

This book highlights the discussions by renown researchers on questions emerged during transition from the relativistic heavy-ion collider (RHIC) to the future electron ion collider (EIC). Over the past two decades, the RHIC has provided a vast amount of data over a wide range of the center of mass energies. What are the scientific priorities, after RHIC is shut down and turned to the future EIC? What should be the future focuses of the high-energy nuclear collisions? What are thermodynamic properties of quantum chromodynamics (QCD) at large baryon density? Where is the phase boundary between quark-gluon-plasma and hadronic matter at high baryon density? How does one make connections from thermodynamics learned in high-energy nuclear collisions to astrophysical topics, to name few, the inner structure of compact stars, and perhaps more interestingly, the dynamical processes of the merging of neutron stars? While most particle physicists are interested in Dark Matter, we should focus on the issues of Visible Matter! Multiple heavy-ion accelerator complexes are under construction: NICA at JINR (4 ~ 11 GeV), FAIR at GSI (2 ~ 4.9 GeV SIS100), HIAF at IMP (2 ~ 4 GeV). In addition, the heavy-ion collision has been actively discussed at the J-PARC. The book is a collective work of top researchers from the field where some of the above-mentioned basic questions will be addressed. We believe that answering those questions will certainly advance our understanding of the phase transition in early universe as well as its evolution that leads to today's world of nature.

Pseudorapidity Asymmetry and Centrality Dependence of Charged Hadron Spectra in D+Au Collisions at Sqrt(sNN)

Pseudorapidity Asymmetry and Centrality Dependence of Charged Hadron Spectra in D+Au Collisions at Sqrt(sNN)
Author:
Publisher:
Total Pages:
Release: 2005
Genre:
ISBN:

Download Pseudorapidity Asymmetry and Centrality Dependence of Charged Hadron Spectra in D+Au Collisions at Sqrt(sNN) Book in PDF, Epub and Kindle

The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at (square root)s{sub NN} = 200 GeV are presented. The charged particle density at mid-rapidity, its pseudorapidity asymmetry and centrality dependence are reasonably reproduced by a Multi-Phase Transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for p{sub T} below 5 GeV/c. The ratio of central to peripheral spectra in d+Au collisions shows enhancement at 2

Relativistic Heavy Ion Physics

Relativistic Heavy Ion Physics
Author: Reinhard Stock
Publisher: Springer Science & Business Media
Total Pages: 701
Release: 2010-04-01
Genre: Science
ISBN: 3642015387

Download Relativistic Heavy Ion Physics Book in PDF, Epub and Kindle

This new volume, I/23, of the Landolt-Börnstein Data Collection series continues a tradition inaugurated by the late Editor-in-Chief, Professor Werner Martienssen, to provide in the style of an encyclopedia a summary of the results and ideas of Relativistic Heavy Ion Physics. Formerly, the Landolt-Börnstein series was mostly known as a compilation of numerical data and functional relations, but it was felt that the more comprehensive summary undertaken here should meet an urgent purpose. Volume I/23 reports on the present state of theoretical and experimental knowledge in the field of Relativistic Heavy Ion Physics. What is meant by this rather technical terminology is the study of strongly interacting matter, and its phases (in short QCD matter) by means of nucleus-nucleus collisions at relativistic energy. The past decade has seen a dramatic progress, and widening of scope in this field, which addresses one of the chief remaining open frontiers of Quantum Chromodynamics (QCD) and, in a wider sense, the "Standard Model of Elementary Interactions". The data resulting from the CERN SPS, BNL AGS and GSI SIS experiments, and in particular also from almost a decade of experiments carried out at the "Relativistic Heavy Ion Collider"(RHIC) at Brookhaven, have been fully analyzed, uncovering a wealth of information about both the confined and deconfined phases of QCD at high energy density.