Finite-t and target mass corrections in off-forward hard reactions

TL;DR

This paper presents a systematic method for calculating kinematic corrections in hard exclusive processes, including all twist-four accuracy terms, with applications to deeply-virtual Compton scattering.

Contribution

It provides a complete expression for the time-ordered product of electromagnetic currents incorporating all relevant kinematic corrections up to twist-four.

Findings

Derived the full expression for the time-ordered product with kinematic corrections

Applicable to deeply-virtual Compton scattering studies

Enhanced accuracy in theoretical predictions for off-forward reactions

Abstract

We describe a systematic approach [1] to the calculation of kinematic corrections ~ t/Q^2, m^2/Q^2 in hard exclusive processes which involve momentum transfer from the initial to the final hadron state. As an example, the complete expression is derived for the time-ordered product of two electromagnetic currents that includes all kinematic corrections due to the quark distribution to twist-four accuracy. The results are applicable e.g. to the studies of deeply-virtual Compton scattering.