Unitarity sum rules and the two-Reggeon cut

Using (s-channel) unitarity sum rules, consistency requirements on the two-reggeon cut are derived. A consistent solution with the (negative) absorptive sign of the cut is found and its magnitude connected to quantities encountered in Mueller's analysis of inclusive cross sections. Prescriptions for cuts in multiparticle processes emerge. A positive sign seems to be incompatible with the sum rules combined with simple crossing requirements. (19 refs).