Charge Conjugation and theτ0Meson

Abstract

The assumption of charge conjugation invariance, as used by Gell-Mann and Pais to discuss the decay of the ${\theta }^0$ meson into two $\pi$ mesons, has been applied to the decay of the ${\tau }^0$ meson into three $\pi$ mesons. Analogous to the ${\theta }^0$-meson case, the ${\tau }^0$ meson must be considered a "particle mixture" exhibiting two distinct lifetimes. There is no absolute selection rule against three-$\pi$-meson decay for either of these two ${\tau }^0$ mesons, but their transition probabilities into three $\pi$ mesons are quite different. For example, if the $\tau$ meson is a pseudoscalar particle, the ratio of these two transition probabilities is ≫100.