The reactions K-p -> Sigma±pi±, Sigma±pi±pi+pi-, and Sigma±pi±K+K- at 4.1 GeV/c and 5.5 GeV/c

The data presented and discussed in this report were obtained from K-p interactions at 4.1 GeV/c and 5.5 GeV/c in the MURA thirty-inch hydrogen bubble chamber. K track lengths equivalent to 0.95 IJ.b per event and 0.27 IJb per event have been analyzed at 4.1 GeV/c and 5.5 GeV/c, respectively. Differential cross sections are given for the ~rr+ final states, and the results obtained in this experiment agree well with extrapolated results from lower energies. The data for Sigma+pi- is interpreted in terms of the Regge pole model. A search for the existence of hyperorin resonances in the mass region above 1900 MeV/c2 is made in the Sigma±pi±K+K- data, but no evidence for such resonances is found. Consistent with results from lower energies, this reaction appears to be dominated by quasi-,three-body processes in which either the Y * (1405), Y * (1520), or p(770) is produced. Cross sections and production angular distributions for the various resonance productions are given. Production of Y (1405), Y (1520), and ¢(1020) are observed in the Sigma±pi±K+K- data. Cross se,ctions and production angular distributions are given for the observed resonant processes. A measurement of the mass and width of the theta(1020) yields a mass of 1020.8 + 1. 0 MeV // and a width of 1. 7+1.8 -1.3 MeV/c2.U of I OnlyThesi