Allan A. Hirata

Observation of correlations between vector-meson and baryon-resonance decays☆

Author(s): Goldhaber, Gerson; Brown, John L.; Butterworth, Ian; Goldhaber, Sulamith; Hirata, Allan A.; Kadyk, John A.; Shen, Benjamin C.; Trilling, George H.

K+ n charge exchange near 1 GeV/c☆

We present cross sections and angular distributions for the reaction K+d → Kopp at 865, 970, 1210, 1365 and 1585 MeV/c. Making corrections for deuterium effects, we observe the following features of the elastic charge exchange process K+n → K0p: a) the c.m. angular distribution becomes increasingly peripheral as the momentum increases from 800 to 1600 MeV/c; b) the forward amplitude is largely real. Attempts to describe the data either in terms of a Regge model or in terms of dominance by an elastic P12 isoscalar KN resonance are discussed.

A study of K+d interactions from 865 to 1585 MeV/c

Abstract We present experimental results on K + d interactions from 865 to 1585 MeV/ c incident beam momentum. We report measurements of several K + d partial cross sections and calculate most of the others using relations derived from isospin conservation and data from other experiments. The most striking feature of the cross section data is the abrupt rise of the total single-pion-production cross section near 1000 MeV/ c . We extract isospin-0 KN partial cross sections and find a rapid quasi-two-body reaction KN → K ∗ N . As in the case of the isospin-1 K + N system, it appears that the structure around 1200 MeV/ c in the total cross section for the isospin-0 K ∗ N system is well reconstructed by the sum of three smoothly varying channel cross sections σ 0 (KN), σ 0 (KN π ) and σ 0 (KN ππ ). We study thereaction KN → K ∗ N near threshold and find that the production and decay angular distributions can be interpreted in terms of t -channel phenomena, specifically a superposition of ω, ϱ, and π exchange. As is true of the isospin-1 KΔ and K ∗ N final states, the isospin-0 K ∗ N state has a behavior near threshold which is not very different from its behavior at much higher energy.