Penguin-Induced Radiative Baryonic B Decays

Weak radiative baryonic B decays $B\to {\text{B}}_1\text{ov}{\text{B}}_2\gamma$ mediated by the electromagnetic penguin process $b\to s\gamma$ have appreciable rates larger than their two-body counterparts $B\to {\text{B}}_1\text{ov}{\text{B}}_2$. The branching ratios for $B^{-}\to \mathrm{\Lambda }\bar{p}\gamma$ and $B^{-}\to {\mathrm{\Xi }}^0{\bar{\mathrm{\Sigma }}}^{-}\gamma$ are sizable, falling into the range of $(1\sim 6)\times {10}^{-6}$ with the value preferred to be on the large side, and not far from the bottom baryon radiative decays ${\mathrm{\Lambda }}_b\to \mathrm{\Lambda }\gamma$ and ${\mathrm{\Xi }}_b\to \mathrm{\Xi }\gamma$ due to the large short-distance enhancement for $b\to s\gamma$ penguin transition and the large strong coupling of the anti-triplet bottom baryons with the B meson and the light baryon. These penguin-induced radiative baryonic B decay modes should be accessible by B factories.