LVI. The properties of charged V-particles

Abstract

Abstract Twenty-one examples of the decay of charged V-particles have been found among 25 000 counter-controlled cloud-chamber photographs obtained on the Pic-du-Midi (2 867 m). These events have been analysed and compared with the data obtained by other groups. The measurements show that, if the majority of the V ±-tracks are produced by one type of particle having a single mode of decay, there must be at least two neutral secondary particles, in addition to the charged secondary particle. The latter is probably a μ- or a π-meson and the combined mass of the neutral particles must be less than 1 000 me . Since the κ-particles, of mass about 1 200 me , which were discovered in photographic emulsions, also decay into a charged meson and at least two neutral particles, it is plausible to assume, provisionally, that the V± -particles and the κ-particles are the same. On this assumption most of the available data concerning V± - and κ-particles can be explained if the unstable particle has a mass of about 1 200 me and decays into a charged μ-meson, a π°-meson and a neutrino, or alternatively into a charged μ-meson and two neutrinos. As yet no direct evidence has been found for the existence of a π°-meson in the decay scheme. One negatively charged V-particle probably produced a neutral V-track and a charged meson.