Pion structure functions at 2 loops: final state interaction with spectator
Abstract
Description
Pion structure functions are considered in the framework of QCD sum rules at the next to leading order. The 2-loop diargam, representing the gluon exchange between the struck quark and spectator, is calculated for space-like pion momentum p^2<0. After Borel transformation we obtain a leading twist correction to the pion structure function, which does not violate Bjorken scaling. Partial results can be used in the calculation of complete set of alpha_s corrections to the pion structure functions, which may serve as an intitial condition in the evolution equation. Probabilistic interpretation of the structure functions is discussed.
11 pages, latex
11 pages, latex