Observation of associated bottom production and decay in a high-energy hadron interaction.

Abstract

Production and decay of a pair of bottom mesons, one charged and one neutral, have been observed in a 200-TeV cosmic-ray helium interaction in an emulsion chamber. Analysis of the event indicates that the charged meson decays most probably via a {ital b}{r arrow}{ital u} quark transition, which would imply a nonzero {ital V}{sub {ital u}{ital b}} element in the Kobayashi-Maskawa matrix. The simplest decay scheme consistent with the data is {ital B}{sup {minus}}{r arrow}{ital D}{sub {ital s}}{sup {minus}}{eta}{eta}. The neutral decay is interpreted as {ital B}{sup 0}{r arrow}{ital D}{sup {minus}}{ital e}{sup +}{nu}.