K^- and p̄ production in Au + Pb collisions at 11.5 A GeV/c

I will present the first results from the E864 collaboration on the production of negative kaons and antiprotons in 10% central 11.5 A GeV/c Au+Pb nucleus collisions at the Brookhaven AGS. E864 is a high rate, open geometry spectrometer, capable of measuring particle production in a range of rapidities and transverse momenta at a single setting of the spectrometer magnets. The results are derived from the analysis of over 20 million central interactions collected in the Fall 1994 run. I will report on K^- production in a rapidity range from 1.9 < y < 2.2 (y_cm=1.6) and 25 < PT < 150 MeV/c, and p̄ production from 1.2 < y < 2.2 and 50 < pr < 400 MeV/c. A comparison with previously published results from E878 is presented and the implications for Ā production are discussed.