Observations on τ- mesons and on K-mesons giving rise to capture stars

Abstract

In an emulsion block detector exposed in the stratosphere three cases of the production of τ-mesons in nuclear disintegrations have been observed and 5 cases of negative K-mesons which when brought to rest are captured by nuclei. In one case the production of a τ-meson is associated with the production of a charged hyperon in the same nuclear event. In another case the production of a negative K-meson is associated with the production of a slow positive K-meson. The production ratio of slow τ-mesons to slow positive π-mesons τ/π ⁺=1.1+0.8% and the ratio of slow negative K-mesons to slow negative π-mesons K⁻/π⁻=0.95±0.5%. The mass of the Τ-meson is found to be M_Τ = 975.9 ±2.2 m_e and that of K⁻-mesons M _K⁻ = 927±75 m_e. Proof is given that all three of the decay products of the τ-mesons are π -mesons. It is suggested that all τ-mesons observed to decay in emulsions are positively charged and that the K⁻-mesons observed by us may be the negative counterpart of this particle. Possible relations between the various phenomenologically distinguished types of charged K-mesons are discussed.