Abstract
We report the first observation of [Formula Presented] in relativistic heavy ion collisions. The transverse momentum spectrum of [Formula Presented] from central [Formula Presented] collisions at [Formula Presented] is presented. The ratios of the [Formula Presented] yield derived from these data to the yields of negative hadrons, charged kaons, and [Formula Presented] mesons have been measured in central and minimum bias collisions and compared with model predictions and comparable [Formula Presented] [Formula Presented] and [Formula Presented] results. The data indicate no dramatic reduction of [Formula Presented] production in relativistic heavy ion collisions despite expected losses due to rescattering effects.