# QM 2011 - XXII International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

May 22 – 28, 2011
Centre Bonlieu
Europe/Zurich timezone

## Local baryon-strangeness correlation from hypernuclei and coalescence volume from light nuclei in relativistic heavy ion collisions

Not scheduled
Théâtre National (Centre Bonlieu)

### Théâtre National

#### Centre Bonlieu

France
Board: 90
Poster Correlations and fluctuations

### Speaker

Dr Song Zhang (Shanghai Institute of Applied Physics, CAS, China)

### Description

The production of hypertriton and light nuclei are simulated in a dynamical coalescence model coupled with a multi-phase transport model (AMPT)~\cite{SZhang10}. The beam energy dependence of strangeness population factor, $S_{3}$ = $^{3}_{\Lambda}H/(^{3}He\times\frac{\Lambda}{p})$, is calculated to study local baryon-strangeness correlation as a valuable tool to probe the nature of the dense matter created in relativistic heavy ion collisions. We find that AMPT with string melting predicts an increase of $S_3$ with increasing beam energy, and is consistent with experimental data, while AMPT with only hadronic scattering results in a low $S_3$ throughout the energy range from AGS to RHIC, and fails to describe the experimental data. And we analyzed coalescence parameters, $B_2$ and $B_3$, based on the production of deuteron, helium-3 and proton. The coalescence parameters of $B_2$ and $B_3$ decrease with increasing of beam energy or number of participant. The value of $B_2$ and $B_3$ in this model are consistent with the measurement by experiment collaboration in nucleus-nucleus collisions at different beam energy~\cite{NA49-07} or in different centralities~\cite{STAR09}. The freeze-out correlation volume, $V^{1-A}_f$ (A is atomic number), is calculated in AMPT model. The results of coalescence parameter and the freeze-out correlation volume follow the relation of $B_A$ $\propto$ $V^{1-A}_f$, which is from coalescence mechanism and observed in experiments~\cite{BAVf,STAR09,HLiu06}. This beam energy and system size dependences indicate the increase of source size in more high energy collisions and in more central collisions. References \bibitem{SZhang10} S. Zhang, J. H. Chen, H. Crawford et~al., {Phys. Lett. B} {\bf 684}, {224} ({2010}). \bibitem{NA49-07} V. L. Kolesnikov (for NA59 Collaboration), {J. Phys. Conf. Ser.} {\bf 110}, {032010} (2008) and references therein. \bibitem{STAR09} B. I. Abelev et~al. (STAR Collaboration), arXiv:0909.0566. \bibitem{BAVf} H. H. Gutbrod et~al., {Phys. Rev. Lett.} {\bf 37}, {667} ({1976}) \bibitem{HLiu06} H. Liu and Z. Xu, arxiv:nucl-ex/0610035.

### Primary author

Dr Song Zhang (Shanghai Institute of Applied Physics, CAS, China)

### Co-authors

Dr Jinhui Chen (Shanghai Institute of Applied Physics, CAS, China) Prof. Yu-Gang Ma (Shanghai Institute of Applied Physics, CAS, China)

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