The $\Lambda \Lambda \to YN$ Weak Transition in Double-$\Lambda$ Hypernuclei

Abstract

We calculate the $\Lambda \Lambda \to YN$ transition rate of ${}_{\Lambda \Lambda }^6$He by the hybrid picture, the $\pi$ and $K$ exchanges plus the direct quark processes. It is found that the hyperon-induced decay is weaker than the nucleon-induced decay, but the former may reveal the short-range mechanism of the weak transition and also give a clear signal of the strong $\Delta I=3/2$ transition. The $\Lambda \Lambda \to YN$ transition in double-$\Lambda$ hypernucleus is complement to the $\Lambda N\to NN$ transition as it occurs only in the J=0 channel, while the J=1 transition is dominant in the $\Lambda N\to NN$ case.

Comments: 9 pages