Probing the helicity structure of $b \to s γ$ in $Λ_b \to Λγ$

Abstract

We investigate the rare decay $Λ_b \to Λγ$ which receives both short and long distance contributions. We estimate the long distance contributions and find them very small. The form factors are obtained from $Λ_c \to Λ\ell \barν_\ell$ using heavy quark symmetry and a pole model. The short distance piece opens a window to new physics and we discuss the sensitivity of $Λ_b \to Λγ$ to such effects.