Polarized Deep Inelastic Diffractive ep Scattering: Operator Approach

Polarized inclusive deep--inelastic diffractive scattering is dealt with in a quantum field theoretic approach. The process can be described in the general framework of non--forward scattering processes using the light--cone expansion in the generalized Bjorken region applying the generalized optical theorem. The diffractive structure functions $g_1^{D(3)}$ and $g_2^{D(3)}$ are calculated in the twist--2 approximation and are expressed by diffractive parton distributions, which are derived from pseudo-scalar two--variable operator expectation values. In this approximation the structure functions $g_2^{D(3)}$ is obtained from $g_1^{D(3)}$ by a Wandzura--Wilczek relation similar as for deep inelastic scattering. The evolution equations are given. We also comment on the higher twist contributions in the light--cone expansion.