Reaction K−+p→K−+p+π−+π+ at 4.6 and 5.0 GeV/c; Evaluation of K−π− Scattering Cross Section

The reaction ${K}^{\ensuremath{-}}+p\ensuremath{\rightarrow}{K}^{\ensuremath{-}}+p+{\ensuremath{\pi}}^{\ensuremath{-}}+{\ensuremath{\pi}}^{+}$ near 5.0 BeV/c has been examined. In events of the type ${K}^{\ensuremath{-}}+p\ensuremath{\rightarrow}{K}^{*0}(890)+p+{\ensuremath{\pi}}^{\ensuremath{-}}$ one-pion exchange appears to explain the interaction. Analysis of the scattering angular distribution at the ${\ensuremath{\pi}}^{\ensuremath{-}}p$ vertex indicates that the $p$ and ${\ensuremath{\pi}}^{\ensuremath{-}}$ are produced as if scattering of the virtual exchanged pion is real. Similar analysis of events of the type ${K}^{\ensuremath{-}}+p\ensuremath{\rightarrow}{N}^{*++}(1236)+{K}^{\ensuremath{-}}+{\ensuremath{\pi}}^{\ensuremath{-}}$, with the assumption of real scattering between the ${K}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}$, yields information on the elastic differential, total elastic, and total cross sections of ${K}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}$ scattering.