A Study of 2-pion production in 10 GeV/c K+ Meson interactions in hydrogen

This thesis contains an analysis of the two reactions, K+p andrarr; K+andpi;+andpi;andminus;p; and K+p andrarr; K0andpi;+andpi;0p at an incident K+ momentum of 10 GeV/c, which were observed in the C.E.R.N. 2m Hydrogen Bubble Chamber. The resonances andDelta;++(1236), K*0(890) and K*0(1420) are strongly produced in these data. To investigate the possible existence of a scalar KN(1100) resonance, calculations were performed on the K*0 andndash; andDelta;++(1236), quasi two-body state, using modified one-pion-exchange formulae. The presence of a large I = 1andfrasl;2, s-wave phase shift in the region of 1.1 GeV/c2 is indicated but is not required to be resonant. The enhancement between 1.2 and 1.45 GeV/c2 in Kandpi;andpi; mass, present in these data, is determined to have a dominant spin-parity of 1+ throughout. Evidence for two 1+ resonances in this mass region is obtained from an analysis of the variations, with mass, of the decay properties of this system. A low mass pandpi;andpi; enhancement is present in the data from K+andpi;+andpi;andminus;p final state, only. A study of the production and decay characteristics of this system would seem to suggest that it is composed of the I = 1andfrasl;2 resonances in the spin-parity series 1andfrasl;2+, 3andfrasl;2andminus;, 5andfrasl;2+, known from elastic andpi;-p phase shift analyses.