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arXiv · 0903.3629

Test the time-reversal modified universality of the Sivers function

Zhong-Bo Kang·Jian-Wei Qiu
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Abstract

We derive the time-reversal modified universality for both quark and gluon Sivers function from the parity and time-reversal invariance of QCD. We calculate the single transverse-spin asymmetry of inclusive lepton from the decay of $W$ bosons in polarized proton-proton collision at RHIC, in terms of the Sivers function. We find that although the asymmetry is diluted from the $W$ decay, the lepton asymmetry is at the level of several percent and is measurable for a good range of lepton rapidity at RHIC. We argue that this measurable lepton asymmetry at RHIC is an excellent observable for testing the time-reversal modified universality of the Sivers function.

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Zhong-Bo Kang, Jian-Wei Qiu. 2009-03-22. Test the time-reversal modified universality of the Sivers function. https://doi.org/10.1103/physrevlett.103.172001

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