Bulk properties at RHIC: systematic study

The global variables like the transverse energy at midrapidity, the charged particle multiplicity at midrapidity and the total multiplicity of charged particles are evaluated in the single-freeze-out statistical model for different centrality bins at RHIC at √ sNN = 130 and 200 GeV. Full description of decays of hadron resonances is applied in these estimations. The geometric parameters of the model are obtained from the fit to the final data on the pT spectra. The predicted values of the global variables agree qualitatively well with the experimental data. The centrality independence of the total number of charged particles per participant pair has been also reproduced.

Section: A Determination Of Geometric Parametersmentioning

confidence: 88%

Section: A Determination Of Geometric Parametersmentioning

confidence: 99%

Centrality dependence of global variables in relativistic heavy ion collisions: FinalpTdata analysis in the framework of a statistical model

Prorok

2006

“…This is the case considered in Ref. [7]: the statistical parameters (T = 160.0 MeV, µ B = 24.0 MeV) are fitted to the STAR particle yield ratios [19] and the geometric parameters to the p T spectra of identified hadrons delivered by the STAR Collaboration in Ref. [20].…”

Section: B Identified Hadron Spectramentioning

confidence: 99%

Statistical hadronization model approach tosNN=200GeV Au-Au collisions:pT<

Prorok

2007

Three possible scenarios of the statistical hadronization model are reexamined with the use of the pT spectra of the PHENIX and very low pT PHOBOS measurements at √ sNN = 200 GeV. These scenarios are: (a) full chemical non-equilibrium, (b) strangeness chemical non-equilibrium and (c) chemical equilibrium. Fits to the spectra are done within the Cracow single-freeze-out model, which takes into account both the expansion and resonance decays. Predictions for spectra of φ, K(892) * 0 and π 0 are also given. The global variables like the transverse energy at midrapidity, the charged particle multiplicity at midrapidity and the total multiplicity of charged particles are evaluated and their predicted values agree qualitatively well with the experimental data. The thorough analysis within this model suggests that the chemical full non-equilibrium case is the least likely and both other cases are of the similar likelihood. It is also shown that if the full chemical non-equilibrium freeze-out took place it could manifest itself in the enhancement of the π 0 -production at very low transverse momenta.

“…We have studied the magnitude of the corrections using various model assumptions as input to the BRAG simulations. Assuming primary Λ/p ratios at √ s N N = 200 GeV similar to those measured at the lower energy [25] and a constant behavior with rapidity, we take these ratios and measured spectra shapes as input to the BRAG code for feed down correction from Λ decays. The simulated tracks are generated for the full phase space, digitized, and go through the real data analysis algorithm, as is done to determine the other correction factors.…”

Section: Centralitymentioning

confidence: 99%

Centrality dependent particle production aty=0andy~1in Au+Au collisions at

Arsene¹,

Bearden²,

Beavis³

et al. 2005

Particle production of identified charged hadrons, π ± , K ± , p, andp in Au+Au collisions at √ sNN = 200 GeV has been studied as a function of transverse momentum and collision centrality at y = 0 and y ∼ 1 by the BRAHMS experiment at RHIC. Significant collective transverse flow at kinetic freeze-out has been observed in the collisions. The magnitude of the flow rises with the collision centrality. Proton and kaon yields relative to the pion production increase strongly as the transverse momentum increases and also increase with centrality. Particle yields per participant nucleon show a weak dependence on the centrality for all particle species. Hadron production remains relatively constant within one unit around midrapidity in Au+Au collisions at √ sNN = 200 GeV.