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Single transverse-spin asymmetry in high transverse momentum pion production in pp collisions

Chris Kouvaris·Jian-Wei Qiu·Werner Vogelsang·Feng Yuan
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Abstract

We study the single-spin (left-right) asymmetry in single-inclusive pion production in hadronic scattering. This asymmetry is power-suppressed in the transverse momentum of the produced pion and can be analyzed in terms of twist-three parton correlation functions in the proton. We present new calculations of the corresponding partonic hard-scattering functions that include the so-called "non-derivative" contributions not previously considered in the literature. We find a remarkably simple structure of the results. We also present a brief phenomenological study of the spin asymmetry, taking into account data from fixed-target scattering and also the latest information available from RHIC. We make additional predictions that may be tested experimentally at RHIC.

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Chris Kouvaris, Jian-Wei Qiu, Werner Vogelsang, Feng Yuan. 2006-09-22. Single transverse-spin asymmetry in high transverse momentum pion production in pp collisions. https://doi.org/10.1103/physrevd.74.114013

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