Atomic mass dependence of Ξ^- and \overlineΞ^+ production in central 250 GeV π^- nucleon interactions

Abstract

We present the first measurement of the atomic mass dependence of central Ξ^- and \overlineΞ^+ production. It is measured using a sample of 22,459 Ξ^-&#39;s and \overlineΞ^+&#39;s produced in collisions between a 250 GeV π^- beam and targets of beryllium, aluminum, copper, and tungsten. The relative cross sections are fit to the two parameter function σ_0 A^α, where A is the atomic mass. We measure α= 0.924+-0.020+-0.025, for Feynman-x in the range -0.09 < x_F < 0.15.