Pomeranchuk Repulsion and Resonance Narrowing

The contribution of the $P$ (Pomeranchuk) and $P^{\prime }$ trajectories to the generalized two-particle (low-energy) potential is shown to be repulsive and effectively of long range. A rough expression for the $P$ potential is given in terms of the high-energy total cross section and associated diffraction peak. It is argued that Pomeranchuk repulsion represents the many-particle channels that dominate high energies and that have an important narrowing effect on resonance widths even though these channels are closed in the low-energy resonance region.