Chapter 39, Problem 26E

To determine

The verification about either or both of these decay schemes possible for the tau particle $\left(\text{a}\right){\tau }^{-}\to e^{-}+{\overline{\nu }}_e+{\nu }_{\tau };\left(\text{b}\right){\tau }^{-}\to {\pi }^{-}+{\pi }^0+{\nu }_{\tau }$.