English

Power corrections to the process $\gamma^{*}\gamma \to \pi\pi$ in the running coupling method

High Energy Physics - Phenomenology 2009-11-10 v2

Abstract

Power-suppressed corrections coming from the end-point integration regions in the amplitude of the process γγππ\gamma^{*}\gamma \to \pi \pi at large Q2Q^2 and small squared center-of-mass energy W2W^2 are calculated in the QCD hard-scattering approach where the amplitudes factorize in a hard perturbatively calculable part and a generalized distribution amplitude. The running coupling method and the technique of infrared renormalon calculus are applied to obtain Borel resummed expressions for the two main components of the process amplitude. Numerical estimates for these power corrections are presented. They are sizeable when Q2<10GeV2Q^2 < 10 GeV^2.

Keywords

Cite

@article{arxiv.hep-ph/0403266,
  title  = {Power corrections to the process $\gamma^{*}\gamma \to \pi\pi$ in the running coupling method},
  author = {S. S. Agaev and M. Guidal and B. Pire},
  journal= {arXiv preprint arXiv:hep-ph/0403266},
  year   = {2009}
}

Comments

15 pages, 5 figures