Transverse Spin Results from STAR
COFFEE_KLATCH · Invited
Abstract
One of the main objectives of the Spin physics program at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory is to study transverse spin effects. Measurements of large Feynman x (xF) neutral pion production in polarized proton collisions at sqrt(s) = 200 GeV has been reported by STAR. Cross section measurements at eta = 3.3, 3.8, and 4.0 were found to be consistent with next-to-leading order perturbative QCD calculations. The analyzing power was found to be large and positive at xF$>$0.3, and consistent with phenomenological calculations based on the Collins effect, the Sivers effect, and initial-state higher twist contributions. This contribution will summarize these measurements, as well as give an outlook of future STAR semi-inclusive measurements to determine the Transversity and Sivers distribution functions.
–
Authors
-
Akio Ogawa
BNL