180 research outputs found
Quark-Gluon Plasma: Present and Future
We review a sample of the experimental results from AGS to SPS and RHIC and
their interpretations towards understanding of the Quark-Gluon Plasma. We
discuss extrapolations of these results to the upcoming LHC experiments.
Finally, we present the plans to probe the QCD critical point with an energy
scan at RHIC and FAIR facilities.Comment: Invited talk at the DAE Symposium on Nuclear Physics (December 2007)
at Sambalpur University, India. 9 page
Event-by-event fluctuations and the QGP phase transition
Fluctuations of thermodynamic quantities are fundamental to the study of QGP phase transition. Event-by-event fluctuations of many quantities have been studied by dedicated heavy-ion experiments. A brief review of recent experimental results is presented. The prospect for future study of fluctuations is discussed
Probing the QCD phase structure using event-by-event fluctuations
Heavy-ion collisions at relativistic energies probe matter at extreme
conditions of temperatures and energy densities. The study of event-by-event
fluctuations of experimental observables is crucial to probe the QCD phase
transition, locate the critical point, and learn about the associated critical
phenomena. At the critical point, all thermodynamic quantities behave
anomalously. Fluctuation measurements provide access to thermodynamic response
functions. We discuss the methods for obtaining the isothermal compressibility
using particle multiplicity fluctuation, and specific heat using fluctuations
in mean transverse momentum, temperature, and energy. Lattice QCD calculations
have predicted non-monotonic behavior in the higher-order cumulants of
conserved quantities at the critical point. Fluctuations in the multiplicity of
charged to neutral particles have been measured to understand the formation of
domains of disoriented chiral condensates. We review the recent fluctuation
results as a function of collision centrality and energy from experiments at
SPS, RHIC, and LHC. In addition, we propose to map the temperature fluctuations
in eta-phi plane to probe local fluctuations of temperature and energy density.Comment: To appear in the proceedings of WWND 2020 conference, 12 pages, 14
figure
Statistical Aspects of Cases Concerning Racial Discrimination in Drug Sentencing: Stephens v. State and U.S. v. Armstrong
Statistical Aspects of Cases Concerning Racial Discrimination in Drug Sentencing: Stephens v. State and U.S. v. Armstrong
Study of dynamical charge fluctuations in the hadronic medium
The dynamical charge fluctuations have been studied in ultra-relativistic
heavy-ion collisions by using hadronic model simulations, such as UrQMD and
HIJING. The evolution of fluctuations has been calculated at different time
steps during the collision as well as different observation window in
pseudorapidity (\DelEta). The final state effects on the fluctuations have been
investigated by varying ~ and the time steps with the aim
of obtaining an optimum observation window for capturing maximum fluctuations.
It is found that ~ between 2.0 and 3.5 gives the best
coverage for the fluctuations studies. The results of these model calculations
for Au+Au collisions at ~=~7.7 to 200~GeV and for Pb+Pb
collisions at 2.76 TeV are presented and compared with available experimental
data from the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron
Collider (LHC).Comment: 6 pages, 4 Figure
Indication of a Co-Existing Phase of Quarks and Hadrons in Nucleus - Nucleus Collisions
The variation of average transverse mass of identified hadrons with charge
multiplicity have been studied for AGS, SPS and RHIC energies. The observation
of a plateau in the average transverse mass for multiplicities corresponding to
SPS energies is attributed to the formation of a co-existence phase of quark
gluon plasma and hadrons. A subsequent rise for RHIC energies may indicate a
deconfined phase in the initial state. Several possibilities which can affect
the average transverse mass are discussed. Constraints on the initial
temperature and thermalization time have been put from the various experimental
data available at SPS energies.Comment: 4 pages and 2 figures, title changed and draft modifie
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