Reactions<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>K</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:mrow><mml:mi>p</mml:mi><mml:mo>→</mml:mo><mml:mi mathvariant="normal">Hyperon</mml:mi><mml:mo>+</mml:mo><mml:mi mathvariant="normal">Meson</mml:mi></mml:math>at 3.5 GeV/<i>c</i>

A study has been made of some of the quasi-two-body final states (in which one of the particles is a hyperon) produced by 3.5-GeV/c K− mesons on protons. The analysis has been performed with 310 000 photographs taken in the 81-cm Saclay hydrogen bubble chamber. The cross sections for most of the reactions are lower than have been observed at lower incident momenta. Many of the reactions are characterized by a forward peaking of the production angular distribution of the final-state meson, but in a few cases a significant backward peak has been observed. Decay distributions of unstable particles have been investigated to obtain more information about the production processes. The Y1*+(1385) decay is consistent with the Y*π− final state being produced by K* exchange, but in the case of the production of vector mesons, it is difficult to draw any conclusion concerning the spin of the exchanged particle. An enhancement was observed at 1645 MeV in the Σ±π∓ system. It is difficult to interpret this in terms of the decay of the neutral Y1*(1660).Received 4 April 1966DOI:https://doi.org/10.1103/PhysRev.152.1148©1966 American Physical Society