An interesting analogy is presented between (i) the properties of the shadow trajectories with singular reduced residues which appear in Regge-pole models for the scattering of particles of unequal mass (Freedman-Wang), and (ii) the well-known infinite-momentum limits of Regge trajectories in potential scattering. A simple model for estimating the effects of those trajectories is presented.

• Received 10 August 1966

DOI:https://doi.org/10.1103/PhysRev.154.1537