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arXiv · 0907.0352

From Diphoton GDAs and Photon GPDs to the chiral odd Photon DA

L. Szymanowski
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Abstract

The photon is a very interesting object for QCD studies since it has both a pointlike coupling to quarks, which yields a perturbative part of photon's wave function, and a non-perturbative coupling related to the magnetic susceptibility of the QCD vacuum and which builds its chiral-odd twist-2 distribution amplitude. The first feature allows us to compute the photon anomalous generalized parton distributions (GPD) and the diphoton generalized distribution amplitudes. The second feature allows us to use a transverse spin asymmetry to probe the chiral odd distribution amplitude of the photon.

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L. Szymanowski. 2009-07-02. From Diphoton GDAs and Photon GPDs to the chiral odd Photon DA. https://arxiv.org/abs/0907.0352

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