Asymmetry Effects in Polarized Hadron Scattering

We calculate the single-spin and double-spin asymmetry differential cross sections for the polarized hadron scattering $PP \to l^+ l^- + jet$ up to $O(\alpha_s)$ by the helicity amplitude method. Numerical results of the differential cross sections, which can be used to probe the spin contents of the proton, are obtained with several sets of polarized parton distribution functions.