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

S. S. Agaev, M. Guidal, B. Pire

Power-suppressed corrections coming from the end-point integration regions in the amplitude of the process ${\gamma }^{\ast }\gamma \to \pi \pi$ at large $Q^2$ and small squared center-of-mass energy $W^…