Inclusive Proton Decay in a Nucleus

The conversion of a proton inside a nucleus into a positron, energy-momentum being shed into the final state, is consdered. For ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ it is found that the lifetime of a proton due to this mechanism is of the same order (probably ∼ 3 times smaller) as that due to the conventional two-quark fusion. The experimental signature is different, a positron track against a star of nuclear fragments, with eventual pions.