KAON INTERFEROMETRY AS SIGNAL FOR THE QCD PHASE-TRANSITION AT RHIC

Pion and kaon correlations in relativistic nuclear collisions are stud ied in the framework of boost-invariant, cylindrically symmetric hydro dynamics, It is investigated how the inverse widths, R-out, R-side, Of the two-particle correlation functions in out-and side-direction depe nd on the average transverse momentum K-perpendicular to of the partic le pair, the initial energy density epsilon(0), and the equation of st ate of the system. The QCD transition leads to a time delay in the exp ansion of the system and consequently to an enhancement of the ratio R -out/R-side. This time-delay signal is found to be particularly strong for large average transverse momenta K-perpendicular to similar to 1 GeV and initial energy densities accessible at RHIC, epsilon(0) simila r to 10-20 GeV fm(-3). Neutral kaon pair correlation functions, which are not influenced by final state Coulomb effects and less contaminate d by resonance decays than pion correlation functions, seem to be the ideal tool to detect this collective time-delay signature of the QCD t ransition. (C) 1997 Elsevier Science B.V.