• DOI:10.1103/PhysRevD.71.054018
• Corpus ID: 119398184

Twist-2 Compton operator and its hidden Wandzura-Wilczek and Callan-Gross structures

@article{Geyer2004Twist2CO,
  title={Twist-2 Compton operator and its hidden Wandzura-Wilczek and Callan-Gross structures},
  author={Bodo Geyer and Dieter Robaschik},
  journal={Physical Review D},
  year={2004},
  volume={71},
  pages={054018}
}

• B. Geyer, D. Robaschik
• Published 27 July 2004
• Physics
• Physical Review D

Power corrections for virtual Compton scattering at leading twist are determined at operator level. From the complete off-cone representation of the twist-2 Compton operator integral representations for the trace, antisymmetric and symmetric part of that operator are derived. The operator valued invariant functions are written in terms of iterated operators and may lead to interrelations. For matrix elements they go over into relations for generalized parton distributions. Reducing to the s-channel relevant part one gets operator preforms of the Wandzura-Wilczek and the (target mass corrected) Callan-Gross relations whose structure is exactly the same as known from the case of deep inelastic scattering; taking nonforward matrix elements one reproduces earlier results [B. Geyer, D. Robaschik and J. Eilers, Nucl. Phys. B704, 279 (2005).] for the absorptive part of the virtual Compton amplitude. All these relations, obtained without any approximation or using equations of motion, are determined solely by the twist-2 structure of the underlying operator and, therefore, are purely of geometric origin.