Production of hypernuclei in a 2.1 GeV/nucleon oxygen beam

Abstract

The first hypernuclei production experiment using a beam of heavy ions from the Lawrence Berkeley Laboratory Bevatron is described. Mass 16 hypernuclei were produced by 2.1 GeV/nucleon $^{16}\mathrm{O}$ ions incident on a polyethylene target. These relativistic hypernuclei were studied with large gap spark chambers that were electronically triggered by the low momentum ${K}^{+}$ meson produced in association. Analysis of 22 events yields a mean lifetime $\ensuremath{\tau}(^{16}Z_{\ensuremath{\Lambda}})=({0.86}_{\ensuremath{-}0.26}^{+0.33})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ sec.NUCLEAR REACTIONS Hypernuclei $(^{16}\mathrm{O},^{16}\mathrm{N}_{\ensuremath{\Lambda}} or ^{16}\mathrm{O}_{\ensuremath{\Lambda}}) {K}^{+}$, $E=2.1$ GeV/nucleon, polyethylene target, ${\ensuremath{\sigma}}_{t}$ roughly measured; mean lifetime of mass 16 hypernuclei measured.