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arXiv · 0705.2481

Single Longitudinal-Spin Asymmetries in Lepton-Pair Production at RHIC and J-PARC

Hiroshi Yokoya
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Abstract

We study the single longitudinal-spin asymmetries in lepton-pair production with large transverse-momentum at RHIC and J-PARC experiments. The asymmetries in the azimuthal angular distribution of a lepton can arise from an absorptive part of production amplitudes. We revisit the one-loop calculation for the absorptive part of production amplitudes in perturbative QCD, and show that the asymmetries can be sizable at RHIC and J-PARC. Measurement of the asymmetries would test the one-loop prediction for the scattering phase of this process, and provide support for a study of the single transverse-spin asymmetries in the same kinematical region.

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Hiroshi Yokoya. 2007-05-17. Single Longitudinal-Spin Asymmetries in Lepton-Pair Production at RHIC and J-PARC. https://doi.org/10.1143/ptp.118.371

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