Interaction of a Negative Heavy Meson

Abstract

An interaction caused by a stopping heavy meson has been observed in emulsion. One of the four particles emitted in the interaction is interpreted as a nuclear fragment with a ${\Lambda }^0$ attached. The subsequent mesonic decay of this bound ${\Lambda }^0$ leads to a $Q$ of 34.2±0.9 Mev. The measured mass of the heavy meson is $1010\pm 200m_e$. The visible kinetic energy released in the interaction it causes is 50±8 Mev.