Semiclassical double-Pomeron production of glueballs and [Formula Presented]

A semiclassical theory of high energy scattering based on interrupted tunneling (instantons) or QCD sphaleron production has been recently developed to describe the growing hadronic cross section and properties of the soft Pomeron. In this work we address double-Pomeron processes in this framework for the first time. We specifically derive the cross section for central production of parity even and odd clusters, scalar and pseudoscalar glueballs, and [Formula Presented] in parton-parton scattering at high energy. We show that the specific dependence of the production cross section on all its kinematical variables compares favorably with the UA8 data on inclusive cluster production, as well as the WA102 data on exclusive central production of scalar glueball and [Formula Presented] in double-Pomeron exchange [Formula Presented] scattering. The magnitude of the cross section and its dependence on kinematic variables is correct, explaining in particular a large deviation from the Pomeron factorization at cluster masses in the range [Formula Presented] GeV reported by UA8.