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Single spin asymmetries in $γ^* γ\to πππ$ at large Q^2

B. Pire·O. V. Teryaev
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Abstract

The $γ^* γ\to πππ$ reaction is analysed in QCD at large photon virtuality Q and small hadronic mass W. Its amplitude factorizes in a $3 π$ generalized distribution amplitude and a hard subprocess $γ^* γ\to q \bar q$ or $γ^* γ\to g g$. The interference of this process with a Brehmsstrahlung process in e e or $e γ$ collisions gives rise to interesting single spin asymmetries, particularly when W is near the $ω$ mass.

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B. Pire, O. V. Teryaev. 2000-07-03. Single spin asymmetries in $γ^* γ\to πππ$ at large Q^2. https://doi.org/10.1016/s0370-2693(00)01279-x

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