Branching ratios in baryon decay

Abstract

We estimate branching ratios for proton (and neutron) decay expected in the S${\mathrm{U}}_5$ grand unified theory of decay with a simple S${\mathrm{U}}_6$-invariant quark model for baryon structure and assuming several possible models for quark kinematics in the decay. Our branching ratios agree in the appropriate limit with two recent estimates. The proton (and neutron) decay into single pions ($\pi e^{+}$ plus $\pi \overline{\nu }$) more than 50% of the time in all models we consider.