ISSN:
1434-6052
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Results of a pion interferometry analysis are presented for the reactions S+C, S+S, S+Cu, S+Ag, S+Au and O+Au at 200 GeV per nucleon. Correlation functions were measured for pairs of negative pions in narrow windows of transverse momentum and rapidity, as a function of the three components of the momentum difference vector in cylindrical coordinates. The measured two-pion correlation functions suggest a space-time evolution of the system which proceeds in the following way for central nucleus-nucleus collisions. After interpenetration of the incident nuclei, the pion source expands in a boost invariant way along the collision axis. Estimates for the proper time interval between the onset of expansion and pion decoupling, as well as for the duration of pion emission are ∼ 4 fm/c and 〈2 fm/c, respectively. Thek T dependence observed forR S is consistent with the effect of resonance decays, alone or combined with slow transverse expansion. A linear dependence of the decoupling volume on the multiplicity is observed and indicates pion decoupling at a constant particle density. Presently available model predictions are briefly discussed
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01496582
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