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Mass and charge distributions have been measured for damped projectile-like fragments in the reaction ' Ge+' 'Ho at 8.5 MeV per nucleon bombarding energy. Coincidences were measured between Zand A-identified projectile-like fragments and angle-correlated heavy reaction partners in order to derive the primary mass distribution for projectile-like fragments. Centroids and variances

Two-pion correlation functions are analyzed at midrapidity for three systems (14.6A GeV/c SiϩAl, SiϩAu, and 11.6A GeV/c AuϩAu͒, seven distinct centrality conditions, and different k T bins in the range 0.1-0.5 GeV/c. Source reference frames are determined from fits to the Yano-Koonin source parametrization. Bertsch-Pratt radius parameters are shown to scale linearly with both number of projectile and total participants as obtained from a Glauber model calculation. A finite lifetime parameter that increases linearly with system/ centrality is also reported. The m T dependences of the Bertsch-Pratt radii for the central SiϩAu and central AuϩAu systems differ only by an overall normalization factor given by the measured system/centrality dependence.

Charged kaon production has been measured in Si+Al and Si+Au collisions at 14.6A GeV/c, and Au+Au collisions at 11.1A GeV/c by Experiments 859 and 866 (the E-802 Collaboration) at the BNL AGS. Invariant transverse mass spectra and rapidity distributions for both K + and K − are presented. The centrality dependence of rapidity-integrated kaon yields is studied. Strangeness enhancement is observed as an increase in the slope of the kaon yield with the total number of participants as well as the yield per participant. The enhancement starts with peripheral Si+Al and Si+Au collisions (relative to N+N) and appears to saturate for a moderate number of participating nucleons in Si+Au collisions. It is also observed to increase slowly with centrality in Au+Au collisions, to a level in the most central Au+Au collisions that is greater than that found in central Si+A collisions. The enhancement factor for K + production are 3.0 ± 0.2(stat.) ± 0.4(syst.) and 4.0 ± 0.3(stat.) ± 0.5(syst.), respectively, for the most central 7% Si+Au collisions and the most central 4% Au+Au collisions relative to N+N at the correponding beam energy.

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