BOSE-EINSTEIN SYMMETRIZATION AND THE ONE-BODY DISTRIBUTIONS IN RELATIVISTIC HEAVY-ION COLLISIONS

In many existing relativistic heavy ion experiments and in future expe riments from several hundred to several thousand identical hadrons (ma inly pions) will be produced in each central collision event. The requ irement that the outgoing many-body wave function for the identical bo sons produced in these collisions be symmetric with respect to particl e label exchange causes the observed momentum distributions to differ from that in the so-called ''freeze out'' region of the source, provid ed the particle emission is mainly incoherent. For high multiplicity e vents the symmetric many-body probability distribution for identical b osons is exceedingly complicated. A straightforward method is presente d for calculating the effects of Bose-Einstein symmetrization on the o bserved one-body distributions for high multiplicity collision events. The method involves an expansion of the many-body probability density in powers of the source function together with a subexpansion based o n the connectivity displayed in diagrammatic representations of the ex change terms. The leading symmetrization correction is shown to be pro portional to the phase space particle density in the ''freeze out'' re gion of the source. Numerical results are presented for Au+Au central collisions at center-of-momentum energies of 200A GeV where moderate, but significant effects are obtained. The range of validity of this ap proach is also discussed. [S0556-2813(98)07605-5].