Multiple pion production in K+-proton collisions at 3.5 GeV/c

An analysis is made of K+ proton interactions in which three or four pions are produced. The experiment was conducted in the Brookhaven 80-inch bubble chamber using an incident beam of 3.5 GeV/c K+ mesons. Events of the type K+ + p → Ko + p + (3 or 4π)+ were selected from the four-prong plus Vo topology. A search is made in these reactions for the production of excited states of the K meson which decay with the emission of one or more pions. The kappa (725) and K∗ (892) are discussed in some detail. Evidence is presented for a K∗ resonance of mass 1305 MeV. Upper limits are measured for the Kω and Kη decays of the K∗(1420). A K∗+ (892)π+ enhancement is observed in this data at 1180 MeV. In addition to a study of K meson excited states, some properties of the ω and η mesons are studied in a production process with very little background.