Comments on the Regge-pole model for the reaction [formula omitted

Abstract

Difficulties of exchange models for the high-energy reaction KN→ K ∗ (890)N are examined in the light of new data. The new experimental results allow an analysis of the reaction K ± p→ K ∗± p independent of low-energy data which strongly influenced our previous analysis. Although consistent with significant exchange amplitudes for the leading trajectories ω and P′ (but not P) at small − t, the fast energy dependence of the high-energy (4–13 GeV/ c) K ± p→ K ∗± p data gives direct evidence for a very important secondary Regge contribution. This dominant low-lying isoscalar contribution remains a problem for the conventional exchange models and cannot be reproduced by a Reggeised absorption-cut model involving leading trajectories. Various models including secondary Regge poles previously used are constructed and the difficulties of some of these are pointed out. A typical Regge-pole model which can successfully reproduce the data on all charge modes is illustrated. This model has isoscalar contributions from the trajectories P′, a comparatively flat ω (without the cross-over zero) and a third vacuum Regge pole P″ introduced in πN elastic scattering.