JET PRODUCTION IN POLARIZED LEPTON-HADRON SCATTERING

We calculate exact analytical expressions for O(alpha(s))3-jet and O(a lpha(s)(2))4-jet cross sections in polarized deep inelastic lepton nuc leon scattering. Introducing an invariant jet definition scheme, we pr esent differential distributions of 3- and 4-jet cross sections in the basic kinematical variables x and W-2 as well as total jet cross sect ions and show their dependence on the chosen spin-dependent (polarized ) parton distributions. Noticeably differences in the predictions are found for the two extreme choices, i.e. a large negative sea-quark den sity or a large positive gluon density. Therefore, it may be possible to discriminate between different parametrizations of polarized parton densities, and hence between the different physical pictures of the p roton spin underlying these parametrizations.