Physical Review Letters 92,17 (2004) 171801;
Measurements of the production of forward high-energy pi(0) mesons from transversely polarized proton collisions at root200 GeV are reported. The cross section is generally consistent with next-to-leading order perturbative QCD calculations. The analyzing power is small at x(F) below about 0.3, and becomes positive and large at higher x(F), similar to the trend in data at roots less than or equal to20 GeV. The analyzing power is in qualitative agreement with perturbative QCD model expectations. This is the first significant spin result seen for particles produced with p(T)>1 GeV/c at a polarized proton collider.
pc cni polarimeter;; high chi-f;; analyzing-power;; polarized antiprotons;; azimuthal asymmetry;; hard-scattering;; pi-0 production;; gev-c;; qcd;; electroproduction
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