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arXiv · 1101.2702

Single spin asymmetry in $\pi p$ Drell-Yan process

Zhun Lu·Bo-Qiang Ma·Jun She
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Abstract

We study the single spin asymmetries for the $\pi p^\uparrow\rightarrow\mu^+\mu^-X$ process. We consider the asymmetries contributed by the coupling of the Boer-Mulders function with the transversity distribution and the pretzelosity distribution, characterized by the $\sin(\phi+\phi_S)$ and $\sin(3\phi-\phi_S)$ azimuthal angular dependence, respectively. We estimate the magnitude of these asymmetries at COMPASS by using proper weighting functions. We find that the $\sin(\phi+\phi_S)$ asymmetry is of the size of a few percent and can be measured through the experiment. The $\sin(3\phi-\phi_S)$ asymmetry is smaller than the $\sin(\phi+\phi_S)$ asymmetry. After a cut on $q_T$, we succeed in enhancing the asymmetry.

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Zhun Lu, Bo-Qiang Ma, Jun She. 2011-01-14. Single spin asymmetry in $\pi p$ Drell-Yan process. https://doi.org/10.1016/j.physletb.2011.01.018

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