M. Vient

Recent results from E802 and E859

Abstract Recent single-particle inclusive measurements and two-particle correlation data from E802 and its succesor, E859, are presented. The K + / π + ratio observed for collisions of 14.6 A·GeV 28 Si ions on various targets is presented as a function of both forward and transverse energy. Source sizes are determined via interferometry using π + , π − , K + and proton pairs.

Antiproton production in 14.6 AGeVc Si+A collisions

Abstract Antiproton production cross sections have been measured for minimum bias and central Si+Al and Si+Au collisions at 14.6 A GeV c . The data presented cover the range of transverse momentum from 0.3 to 1.2 GeV c and lab rapidities from 1.1 to 1.7 units. The relative p π − and p K − yields are found to be the smallest for the heaviest system measured, central Si+Au collisions. For these collisions, the p π − ratio, determined from integrated yields for 1.1⩽y⩽1.7, is (0.84±0.07)×10−3. In the same rapidity interval, the average antiproton inverse m⊥ slope is 141±14 MeV for central Si+Al and central Si+Au collisions.

Centrality dependence of K+ and π+ multiplicities from Si + A collisions at 14.6 A GeV/c☆

Abstract K + and π + multiplicities have been measured in magnetic spectrometer for Si++ Al, Si+ Cu and Si + Au collisions at 14.6 A GeV/ c incident momentum. The multiplicities were obtained for five different windows of forward kinetic energy as detected in a zero degree calorimeter. The K + / π + multiplicity ratio ranges from ≈9% in peripheral interactions to 19% in central Si+Au. The largest K + / π + ratios are observed for those events for each target that leave the least energy in the zero degree calorimeter and the ratio increases with target mass. The observations suggest that multiple interactions are important in the particle production mechanism.

Intermittency in central collisions of 16O+A at 14.6A GeV/c☆

Abstract Fluctuations in pseudorapidity distributions of charged particles from central collisions of 16 O+Al and 16 O+Cu at 14.6 A GeV/ c are analyzed using scaled factorial moments. A power-law growth of moments with decreasing bin size is observed down to δη ∼ 0.1. About half the measured signal remains after making corrections based on Monte Carlo calculations with Fritiof and GEANT which include γ-conversions, Dalitz decays and detector effects.

Bose-Einstein correlations in 14.6 A · GeV/c 28Si + A collisions

Abstract The E802 spectrometer at the Brookhaven AGS has been used to obtain two-particle inclusive pion distributions from E / A = 14.6 GeV 28 Si + 197 Au arid 27 A1 interactions. Data are presented for pions near center-of-mass rapidity, in the nucleon-nucleon frame, from central events. We present preliminary results for source distribution parameters obtained by fitting the two-particle correlation function. The potential for studying kaon correlations in the E802 apparatus is also discussed.

Particle production in pA and AA collisions at AGS

Production of light particles (π±,K±,p) has been measured in both Si+A and p+A collisions. Several interesting features have been observed, among which are: the enhanced K+/π+ ratio and the larger 〈mt〉 for K+ and proton. Comparisons between ≊pp, pA and SiA collisions are discussed.

Spectrometer results from BNL E802

Measurements of collisions of 14.5 GeV/c per nucleon 28Si ions with nuclear targets using the BNL E802 spectrometer are presented. A description of the experiment and preliminary particle ratios are discussed.