arXiv 0803.17772008-03-12hep-ph

Dual parameterization and Abel transform tomography for twist-3 DVCS

Alena M. Moiseeva, Maxim V. Polyakov

备注：: 11 pages, 1 eps figure
发表信息：: Nucl. Phys.B832:241, 2010
DOI：: 10.1016/j.nuclphysb.2010.02.008

英文摘要：

We derive dual parameterization for the DVCS amplitude to the twist-3 accuracy. The relation of the dual parameterization to the Abel transform tomography for amplitudes of hard exclusive processes is elaborated. We prove dispersion relations for the twist-3 DVCS amplitude in the Wandzura -- Wilczek approximation and show that the subtraction constant is given by the D-term form factor. The same as in the case of twist-2 DVCS amplitude.

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