Angular Distribution and Polarization of Photons in the Inclusive Decay $Λ_b\to X_s\,γ$

Abstract

We study the angular distribution of photons produced in the inclusive decay of a polarized $Λ_b$, $Λ_b\to X_s\,γ$, using the technique of Heavy Quark Effective Theory. Finite non-perturbative corrections are obtained relative to the free quark decay $b\to sγ$. These corrections affect significantly the intensity and polarization of photons emitted at small angles relative to the $Λ_b$ spin direction.