Hypernuclei in some hammer-like events recorded in a photonuclear emulsion irradiated with stopping K k mesons

Abstract

In a nuclear emulsion stack exposed to K − -mesons a total of 675 events were found in which incident stopping particles interacted with emulsion nuclei to produce the 8Li or 8B nuclei (hammer-like events). It was established that 70% of the events pertain to the K − -meson interaction, while 18.25% belong to the stopping π −-meson interaction. Comparing these productions it has been found that in about 5% of events π 0-meson hypernuclei occur in hammer-like events produced by stopping K − -mesons. Data are reported on one case of a π − -mesonic hypernucleus decaying in such a way that, in addition to the emission of a π − -meson, a hammer-like event is produced, i.e. two short-range particles and an electron are emitted. This event may be ascribed to the decay of a λ 5Li hypernucleus.