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arXiv · hep-ph/9905497

A New Mechanism for Single Spin Asymmetries in Strong Interactions

N. I. Kochelev
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Abstract

It is shown that the contribution of the instantons to the fragmentation of quarks leads to the appearance of a imaginary part in diagrams of quark-quark scattering at large transfer momentum. The imaginary part comes from the analytical continuation of the instanton amplitudes from Euclidean to Minkowsky space-time and reflects quasiclassical origin of instanton solution of QCD equations of motion. This phenomenon and instanton--induced quark spin-flip give a new nonperturbative mechanism for the observed anomalous single-spin asymmetries in hadron-hadron and lepton-hadron interactions.

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N. I. Kochelev. 2001-02-04. A New Mechanism for Single Spin Asymmetries in Strong Interactions. https://doi.org/10.1134/1.1343147

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