Single Electron Detection for SLD Crid and Multi - Spectroscopy in Negative Kaon Proton Interactions at 11 Gev/c

This thesis consists of two independent parts: development of single electron detectors and a pulse finding algorithm for the Cherenkov Ring Imaging Detector (CRID) for the SLD Detector at SLAC; and the analyses of unflavored, light quark meson systems using data from the LASS Spectrometer. The CRID sections describe the design, construction, and testing of the multi-wire-proportional chambers used to measure all three co-ordinates of the conversion of UV Cherenkov photons into single electrons in the CRID drift boxes. The detectors use charge division to measure one of the co-ordinates and were carefully designed and built to provide 1 mm resolution. The software algorithm used for CRID to determine the co-ordinates of signals in the digitized data is also described. The algorithm uses knowledge of the fixed pulse shape to deconvolve the amplifier shape from the data, providing good single pulse resolution and excellent double pulse separation. The spectroscopic analyses are based on data from a 4.1 (nb)^{-1} exposure of the LASS Spectrometer in K^-p interactions at 11 GeV/c. The channels Lambda pi^{+}pi^{-} and Lambdapi^{+ }pi^{-}pi^0 are studied in detail. Brief surveys of Lambda pi^{+}pi^{-} pi^{+}pi^{-} and Lambdapi^{+ }pi^{-}pi^{+ }pi^{-}pi^0 are presented. A partial wave analysis of the pi ^{+}pi^{-} system in the Lambdapi^{+ }pi^{-} channel provides evidence for a spin 1 resonance at about 1.3 GeV/c ^2. A fit of this new state, the rho(1300), gives a mass of 1290_sp {-30}{+20}MeV/c^2 and a width of 120_sp{-50} {+60}MeV/c^2. The elasticity of the rho(1300) is estimated as ~5%. Some evidence of rho(1690) production is seen in the pi^{+}pi^{-} system. A partial wave analysis of the pi ^{-}pi^{0} system produced against a backward-going Sigma ^+(1385) in Lambdapi ^{+}pi^{-}pi ^0 again shows evidence of rho (1300) production, with parameters consistent with the pi^{+}pi^ {-} analysis. The examinations of the 4 pion mass spectra in Lambdapi^{+}pi ^{-}pi^{+}pi ^{-} and Sigma^+ (1385)pi^{+}pi ^{-}pi^{-}pi ^0 do not provide any definite evidence of rho(1300) production. The upper limits on the 4pi to 2pi branching ratios are 3 for the neutral and 6 for the charged system. Data for the K_sp{rm S}{0}K^-, K^+K^-, and {| K}^0K ^{+/-}pi^mp modes previously analysed by LASS are presented with attention to possible contributions from rho(1300). No evidence of rho (1300) is seen.