Measurement of [formula omitted] annihilation cross sections into charged particles in the momentum range 374–680 MeV/ c

Abstract

pp annihilation cross sections into 2-, 4- and 6-prong topologies, and the exclusive annihilation cross sections for the π + π −, K +K −, π + π − π 0, π + π + π − π −, π + π + π − π − π 0, π + π + π + π − π − π −, and π + π + π + π − π − π − π 0 channels in the momentum range 374–680 MeV/ c were measured. No prominent structure was observed in the momentum dependence of any of the above cross sections, but a small enhancement in the cross section was observed at 490 MeV/ c corresponding to the S meson mass in the topological, and π + π − π 0 and π + π + π − π − π 0 cross sections. If the extensive of the S meson with a mass and width of 1935.5 and 2.8 MeV/ c 2 is assumed, our measurement gives a total resonant annihilation cross section into charged particles of 10.0±3.0 mb.