We discuss the Regge prediction for the behavior of inclusive cross sections near the kinematic boundary, and we compare it with a recent conjecture of Chou and Yang. Some existing experimental data are analyzed and, in particular, we find no evidence yet for diffraction dissociation into high masses (three-Pomeranchon coupling).

• Received 10 February 1971

DOI:https://doi.org/10.1103/PhysRevLett.26.1076