Entropy Analysis in Relativistic Heavy-Ion Collisions

Entropy creation in multiparticle system is investigated by analysing the experimental data on ion-ion collisions at AGS and SPS energies and the results thus obtained are compared with those predicted by multiphase transport and correlation-free Monte Carlo models. Entropies produced in limited- and full-phase space are observed to increase with increasing beam energy. The entropy values, normalized to the maximum rapidity and plotted against pseudorapidity (bin width also normalized to the maximum rapidity), are found to be energy independent, exhibiting a kind of entropy scaling. Such scaling is observed in the full phase space as well as in the regions confined to the forward or backward hemispheres. The findings also reveal that there exist strong correlations amongst the particles produced in the forward and backward hemispheres around the midrapidity. These correlations are found to be of short range in nature, and the contributions from the long-range correlations seem to be absent. PACS numbers: 25.75-q, 25.75.Gz.

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Phase-space description of momentum spectra in relativistic heavy-ion collisions

Nuclear Physics A ◽

10.1016/j.nuclphysa.2005.10.013 ◽

2006 ◽

Vol 765 (1-2) ◽

pp. 226-251

Author(s):

Werner Deinet ◽

Dirk H. Rischke

Keyword(s):

Phase Space ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Relativistic Heavy Ion Collisions ◽

Ion Collisions ◽

Momentum Spectra ◽

Space Description

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Revisiting directed flow in relativistic heavy-ion collisions from a multiphase transport model

The European Physical Journal A ◽

10.1140/epja/i2017-12431-2 ◽

2017 ◽

Vol 53 (12) ◽

Cited By ~ 8

Author(s):

Chong-Qiang Guo ◽

Chun-Jian Zhang ◽

Jun Xu

Keyword(s):

Heavy Ion Collisions ◽

Transport Model ◽

Heavy Ion ◽

Relativistic Heavy Ion Collisions ◽

Directed Flow ◽

Multiphase Transport ◽

Ion Collisions

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POPULATION OF MULTI-QUARK STATES IN EXOTIC MULTIPLETS AND THERMALIZATION IN ULTRA-RELATIVISTIC HEAVY ION COLLISIONS

International Journal of Modern Physics E ◽

10.1142/s0218301308010386 ◽

2008 ◽

Vol 17 (06) ◽

pp. 965-1014 ◽

Cited By ~ 3

Author(s):

STEFAN SCHERER ◽

MARCUS BLEICHER ◽

STEPHANE HAUSSLER ◽

HORST STÖCKER

Keyword(s):

Phase Space ◽

Thermal Model ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Relativistic Heavy Ion Collisions ◽

Recent Discussion ◽

Ion Collisions ◽

Model Predictions ◽

Exotic Hadrons ◽

Equal Population

The recent discussion about experimental evidence for pentaquark states has revitalized the interest in exotic hadrons. If such states really exist, it is natural to assume that they will be formed at the late hadronization stage of ultra-relativistic heavy ion collisions, given the success of quark recombination models in the description of hadronization. Here, we apply the qMD model to study the formation of color neutral exotic multi-quark clusters at hadronization. We search for color neutral clusters made up of up to six color charges, respectively. We thus obtain estimates for the numbers and phase space distributions of exotic hadronic states produced by clustering in heavy ion collisions, including the members of the pentaquark multiplets. We obtain particle abundances that are smaller than thermal model predictions. Moreover, the results obtained in recombination from ultra-relativistic heavy ion collisions can be compared to the estimates based on equal population of the corresponding multiplets, and to results from fully thermalized systems. We find that the distribution of exotic hadrons from recombination over large multiplets provides a sensitive signal for thermalization and decorrelation of the initial, non-equilibrium state of the collision.

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