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

Abstract.Power-suppressed corrections coming from the end-point integration regions in the amplitude of the process $\gamma^{*}\gamma \to \pi\pi$ at large Q2 and small squared center-of-mass energy W2 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 < 10 GeV2.