Determination of small x shadowing corrections at DESY HERA - art. no. 054010

The recent F-2 data can be described using the DGLAP evolution equations wi th an appropriate choice of input distributions and the choice of the start ing scale for the Q(2) evolution. We demonstrate in this paper that we cann ot conclude that there are no significant shadowing corrections in the DESY HERA kinematic region using F-2 data only. In this paper we calculate the shadowing corrections to the longitudinal structure function F-L(x,Q(2)) an d to the charm component of the proton structure function F-2(c)(x,Q(2)) in the HERA kinematic region using an eikonal approach. We demonstrate that t he shadowing corrections to these observables an very large and that charm production is strongly modified at small x. Our results agree with the few recent HI data. [S0556-2821(99)05103-6].