Pion entropy and phase space density in RHIC collisions

• Autorzy: Cramer J.
• Konferencja: Proceedings of the 2nd Warsaw Meeting on Particle Correlations and Resonances in Heavy Ion Collisions, 15-18 October 2003, Warsaw, Poland
• Języki publikacji: EN

Abstrakty

EN

We present the source-averaged phase space density , the entropy per particle S pi/N pi, and the total pion entropy per participant (dSpi/dy)/Np extracted at midrapidity in six momentum intervals and seven centrality intervals, for pions produced in sNN = 130 GeV Au+Au collisions at RHIC. These are inferred from measured pi- momentum spectra and HBT correlation analysis of pion data from the STAR detector. The source-averaged pion phase space density reaches a plateau with centrality and is significantly larger than that observed for sNN = 17 GeV Pb+Pb central collisions at the CERN SPS. The entropy per particle Spi/Npi is relatively low, approaching the Landau limit. The total pion entropy per participant (dSpi/dy)/Np is about 6.5 š 0.1, independent of centrality, suggesting that there is no per-participant increase in initial entropy production with increasing collision centrality.

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2004
• Tom: Vol. 49,suppl.2
• Strony: 41--44
• Opis fizyczny: Bibliogr. 8 poz., rys.

Twórcy

autor

Cramer J.

• Center for Experimental Nuclear Physics and Astrophysics, Department of Physics, University of Washington, Seattle, WA 98195-1560, USA, Tel.: [phone], Fax: [phone],,

Bibliografia

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