Angular Distribution and Polarization of Photons in the Inclusive Decay ${\Lambda }_b\to X_s\gamma$

Abstract

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

Comments: 10 pages, LaTeX, uses epsf, 2 figures appended as uuencoded, compressed eps tar-files