[QUE/QFT-15002] \(\Lambda \) Hyperon Decay

The interaction of \(\Lambda^0\) hyperon, responsible for decay into a proton
and a \(\pi^-\), is given by \[ H_\text{int} =  \bar{\psi}_p(x) ( g -
g^\prime\gamma_5)\psi_\Lambda(x) \phi_\pi ^\dagger + h.c. \]
(a) Give examples of three virtual processes allowed in the first order of this interaction term.

(b) Show that the partial decay rate of \(\Lambda^0 \longrightarrow p + \pi^-\) is given by
\[ \Gamma = \frac{1}{4\pi}\frac{|\vec{p}|}{M_\Lambda}\left(|g|^2(E_p+M_p) + |g^\prime|^2
(E_p-M_p) \right)\]

Download attachment for full solution