Current densities and operator phenomenology on the light cone

Abstract

For any inclusive or exclusive process, which is determined by a matrix element of two current densities, in general a large number of different limits of the Bjorken type for the invariant variables can be found leading to light cone diminance. The same is true for certain semi-hadronic processes at low external momenta, but with the emphasis on the ultra-violet region for the internal integration. We propose to include in the general light cone expansion of two current densities - to be used in conjunction with the limits mentioned above - besides the vector and axial-vector current densities, also the other Dirac densities (scalar, pseudoscalar, tensor). The formalism describes then half integer powers in corrections to scaling laws as well.