# $K^-$ and $\bar p$ Spectra for Au+Au Collisions at $\sqrt{s}$ = 200 GeV from STAR, PHENIX and BRAHMS in Comparison to Core-Corona Model Predictions

Abstract : Based on results obtained with event generators we have launched the core-corona model. It describes in a simplified way but quite successfully the centrality dependence of multiplicity and  of identified particles observed in heavy-ion reaction at beam energies between $\sqrt{s}$ = 17 GeV and 200 GeV. Also the centrality dependence of the elliptic flow, $v_2$, for all charged and identified particles could be explained in this model. Here we extend this analysis and study the centrality dependence of single particle spectra of $K^-$ and ${\bar p}$ measured by the PHENIX, STAR and BRAHMS collaborations. We find that also for these particles the analysis of the spectra in the core-corona model suffers from differences in the data published by the different experimental groups, notably for the pp collisions. As for protons and $K^+$ for each experience the data agree well with the prediction of the core-corona model but the value of the two necessary parameters depends on the experiments. We show as well that the average momentum as a function of the centrality depends in a very sensitive way on the particle species and may be quite different for particles which have about the same mass. Therefore the idea to interpret this centrality dependence as a consequence of a collective expansion of the system, as done in blast way fits may be premature.
docType_s :
Conference papers
6th International Workshop on Critical Point and Onset of Deconfinement, Aug 2010, Dubna, Russia. 75, pp.640-645, <10.1134/S1063778812050237>
Domain :

http://hal.in2p3.fr/in2p3-00666029
Contributor : Dominique Girod <>
Submitted on : Friday, February 3, 2012 - 1:00:52 PM
Last modification on : Friday, June 15, 2012 - 4:00:21 PM

### Citation

C. Schreiber, Klaus Werner, Jörg Aichelin. $K^-$ and $\bar p$ Spectra for Au+Au Collisions at $\sqrt{s}$ = 200 GeV from STAR, PHENIX and BRAHMS in Comparison to Core-Corona Model Predictions. 6th International Workshop on Critical Point and Onset of Deconfinement, Aug 2010, Dubna, Russia. 75, pp.640-645, <10.1134/S1063778812050237>. <in2p3-00666029>