ar X iv : h ep - p h / 01 02 22 4 v 1 1 8 Fe b 20 01 Resummation of target mass corrections in two - photon processes : twist - two sector
نویسندگان
چکیده
Resummation of target mass corrections in two-photon processes: twist-two sector. Abstract We develop a formalism for the resummation of target mass corrections in off-forward two-photon amplitudes given by a chronological product of electromagnetic currents, arising in e.g. deeply virtual Compton scattering. The method is based on a relation of composite operators with a definite twist to harmonic tensors, which form an irreducible representation of the Lorentz group. We give an application of the framework for the matrix elements of twist-two operators.
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