Single Meson Production in Photon-Photon Collisions and Infrared Renormalons

Abstract

In this article, we investigate the contribution of the higher-twist Feynman diagrams to the large-$p_T$ inclusive single meson production cross section in photon-photon collisions and present the general formulas for the higher-twist differential cross sections in case of the running coupling and frozen coupling approaches. The structure of infrared renormalon singularities of the higher-twist subprocess cross section and the resummed expression (the Borel sum) for it are found. We compared the resummed higher-twist cross sections with the ones obtained in the framework of the frozen coupling approach and leading-twist cross section. We obtain, that ratio $R=({\Sigma }_{M^{+}}^{HT}{)}^{res}$ / $({\Sigma }_{M^{+}}^{HT}{)}^0$, for all values of the transverse momentum $p_T$ of the meson identically equivalent to ratio $r$=(${\Delta }_M^{HT}{)}^{res}$ / $({\Delta }_M^{HT}{)}^0$. It is shown that the resummed result depends on the choice of the meson wave functions used in calculation. Phenomenological effects of the obtained results are discussed.

Comments: 45 pages, 33 figures, 4 tables