Rates for the reactions $$\bar pp \to \pi \phi $$ and? ?

Abstract

We study pp annihilation at rest into πφ and γφ. Rescattering by K * K + K * K and ρ + ρ − for pp → πφ states is sizable, of order (0.90 to 2.6) × 10 −4 in the branching ratio, but smaller than experiment. For pp → γφ the rescattering contributions are negligible, but the γφ channel is well explained by a ρφ intermediate state combined with vector meson dominance.

Study of isospin violating φ excitation ine+e−→ ωπ0

“…The form factor F (p 2 ), which takes care of the off-shell effects of the exchanged particles [23,24,25], is usually parameterized as…”

Interpretation of experimentalJPCexotic signals

“…For this we use a doorway calculation, the procedures for which are well established [18]. We use the simplest approach to provide an upper limit.…”

“…Here we have contracted the Lorentz indices on the internal vector particles in the usual way [18], effectively working in the "Feynman gauge". Integration is performed over the loop momentum.…”

“…The procedure we adopt is that of a doorway calculation with on-shell mesons [18], which provides an upper limit. An essential ingredient is the presence of an allowed dominant decay which can couple strongly to the channel of interest.…”

“…Integration is performed over the loop momentum. We evaluate the doorway amplitude in the rest frame ofρ using conservation of momentum at the vertices and the Cutkovsky rules to obtain [18] …”