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Non-Standard Time Reversal and Transverse Single-Spin Asymmetries

M. Anselmino·V. Barone·A. Drago·F. Murgia
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Abstract

A system of quarks interacting with chiral fields is shown to provide a physical realization of a "non-standard" time reversal for particle multiplets which mixes the multiplet components. We argue that, if the internal structure of the nucleon is governed by a chiral dynamics, the so-called T-odd quark distribution functions are not forbidden by time-reversal invariance and hence might be non vanishing. This agrees with some other recent results. From a phenomenological point of view, this would give rise to single-spin asymmetries in inclusive processes involving a transversely polarized nucleon: in particular, in pion lepto- and hadro-production and in Drell-Yan processes.

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M. Anselmino, V. Barone, A. Drago, F. Murgia. 2002-09-06. Non-Standard Time Reversal and Transverse Single-Spin Asymmetries. https://arxiv.org/abs/hep-ph/0209073

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