A New Mechanism for Single Spin Asymmetries in Strong Interactions
نویسنده
چکیده
It is shown that the euclidean origin of the instanton leads to the appearence of a large imaginary part in some diagrams for hadron production in quark-quark scattering. This phenomenon and instanton–induced quark spin-flip give the fundamental QCD mechanism for the observed large single-spin asymmetries in hadron-hadron and lepton-hadron interactions. 1 Talk presented at the Workshop ”Polarized Protons at High Energies-Accelerator Challenges and Physics Opportunities”, 17-20 May, 1999, DESY, Hamburg
منابع مشابه
ar X iv : h ep - p h / 97 11 27 4 v 1 1 0 N ov 1 99 7 Instantons and Single Spin Asymmetries
A new mechanism for single spin asymmetries in strong interaction is proposed. It is based on instanton–induced nonperturbative chromomagnetic quark–gluon interaction. We estimate the contribution of this interaction to single spin asymmetry in quark–quark scattering. It is shown, that interference between quark spin–flip amplitude induced by instantons and spin–nonflip amplitude, which is rela...
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