STRANGE MESON SPECTROSCOPY IN Km AND K$ AT 11 GeV/c AND CHERENKOV RING IMAGING AT SLD *

This thesis consists of two independent parts; development of Cherenkov Ring Imaging Detector (GRID) system and analysis of high-statistics data of strange meson reactions from the LASS spectrometer. Part I: The CIUD system is devoted to charged particle identification in the SLAC Large Detector (SLD) to study e+ecollisions at ,/Z = mzo. By measuring the angles of emission of the Cherenkov photons inside liquid and gaseous radiators, r/K/p separation will be achieved up to N 30 GeV/c. The signals from CRID are read in three coordinates, one of which is measured by charge-division technique. To obtain a N 1% spatial resolution in the chargedivision, low-noise CRID preamplifier prototypes were developed and tested resulting in < 1000 electrons noise for an average photoelectron signal with 2 x lo5 gain. To help ensure the long-term stability of CRID operation at high efficiency, a comprehensive monitoring and control system was developed. This system continuously monitors and/or controls various operating quantities such as temperatures, pressures, and flows, mixing and purity of the various fluids. The results from the engineering run and initial physics run of the CRID in the SLD experiment show that the CRID hardware performs well and produces Cherenkov rings. Part II: Results from the partial wave analysis of strange meson final states in the reactions K-p + K-wp and K-p + rc$n are presented. The analyses are based on data from a 4.1 event/rib exposure of the LASS spectrometer in K-p interactions at 11 GeV/c. The data sample of K-wp final state contains N lo5 events, which is at least 25 times larger than in any other experiments. F’rom the partial wave analysis,