Measurement of the forward-backward asymmetry of Lambda and (Lambda)over-bar production in p(p)over-bar collisions

We study Lambdaand ( Lambda) over bar productionasymmetries in p (p) overbar -> Lambda(( Lambda) overbar )X, p (p) overbar -> J/psi Lambda(( Lambda) overbar )X, and p (p) overbar -> mu(+/-) Lambda(( Lambda) overbar )X events recorded by the D0 detector at the Fermilab Tevatroncollider at root s = 1.96 TeV. We find an excess of Lambda's (( Lambda) overbar 's) produced in the proton ( antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the ( Lambda) overbar/ Lambdaproduction ratio, measuredby several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss," i.e., the rapidity difference of the beam proton and the lambda.