PHYSICAL REVIEW D, cilt.80, sa.1, 2009 (SCI-Expanded)
In this article, we investigate the contribution of the higher-twist Feynman diagrams to the large-p(T) inclusive pion production cross section in proton-proton collisions and present the general formulas for the higher-twist differential cross sections in the 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(+HT)(pi))(res)/(Sigma(+HT)(pi))(0), for all values of the transverse momentum p(T) of the pion identically equivalent to ratio r=(Delta(HT)(pi))(res)/(Delta(HT)(pi))(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.