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arXiv · 1509.07554

Collinear Twist-3 Approach to Transverse Single-Spin Asymmetry in Proton-Proton Collision

Koichi Kanazawa·Andreas Metz·Yuji Koike·Daniel Pitonyak
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Abstract

We present our recent analysis on the transverse single-spin asymmetry (SSA) in inclusive pion and direct-photon production in pp collisions for RHIC kinematics. The analysis includes the contributions from twist-3 quark-gluon-quark correlations in the proton and twist-3 fragmentation effects for the pion. Some of the functions appearing in the formula for the SSA, such as the soft-gluon-pole Qiu-Sterman function, the nucleon transversity, and the Collins function were fixed consistently with the SSA data in semi-inclusive DIS and in e+e- annihilation, so that our analysis is free from the sign mismatch problem.

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Koichi Kanazawa, Andreas Metz, Yuji Koike, Daniel Pitonyak. 2015-09-24. Collinear Twist-3 Approach to Transverse Single-Spin Asymmetry in Proton-Proton Collision. https://arxiv.org/abs/1509.07554

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