Phenomenological model for the Kbar N --> K Xi reaction

A phenomenological model for the Kbar N --> K Xi reaction is suggested. The model includes s and u channel exchanges by Lambda, Sigma, Sigma(1385), and Lambda(1520) and s channel exchanges by above-threshold hyperonic resonances. Explicit expression for the propagator for a particle with spin 7/2 is presented. High-mass and high-spin resonances play a significant role in the process. We deal with the whole set of existing experimental data on the cross sections and polarizations in the energy range from the threshold to 2.8 GeV in the center-of-mass system and reach a good agreement with experiments. Applications of the model to other elementary reactions of Xi production and to Xi hypernuclear spectroscopy are briefly discussed.Comment: Published version; minor change

Total Absorption Shower Counter Test

We propose to conduct a short test to check the basic concepts used in the Total Absorption Shower Counter (TASC) being developed for the Alvarez cosmic-ray experiment (BCR-5) on the HEAO-B satellite. The objective is to ascertain whether the probability for an incoming proton of energy E {ge} 100 GeV to interact in the TASC and simulate the response due to an incoming e{sup {+-}} is smaller than 10{sup -4}. We will thereby obtain a preliminary estimate of whether the TASC should be able to distinguish incident e{sup {+-}} from incident protons to one part in 10{sup 4} over the BCR-5 momentum range from 5 to 10{sup 4} GeV/c

The small K π component in the K* wave functions

We use a recently developed formalism which generalizes the Weinberg's compositeness condition to partial waves higher than s-wave in order to determine the probability of having a $K \pi$ component in the $K^*$ wave function. A fit is made to the $K \pi$ phase shifts in p-wave, from where the coupling of $K^*$ to $K \pi$ and the $K \pi$ loop function are determined. These ingredients allow us to determine that the $K^*$ is a genuine state, different to a $K \pi$ component, in a proportion of about 80%