SU(3) content of the Pomeranchuk singularity

The SU(3) structure of isoscalar, even-signature meson-exchange amplitudes in elastic meson-baryon scattering is explored. The forward amplitudes corresponding to singlet and octet exchange exhibit complicated energy dependences, neither of which can be ascribed to the exchange of a single Regge pole with an energy-independent intercept. A contribution identified with Pomeron exchange is isolated. It corresponds to a Regge pole with intercept above. 1. A description in terms of a mostly singlet Pomeron and an ideally mixed f0 trajectory gives an excellent account of total cross sections from 6 to 280 GeV/c. For t<0, the singlet amplitude becomes increasingly dominant over the octet amplitude.