Determination of the HQET Parameters from the $B\to X_s\gamma$ Decay

Abstract

We combine the resummations for radiative corrections and for the heavy quark expansion to study the inclusive radiative decay $B\to X_s\gamma$. The infrared renormalon ambiguity is also taken into account. Including both theoretical and experimental uncertainties, we determine the allowed domain for the HQET parameters $\bar{\Lambda }$ and ${\lambda }_1$ centered at $\bar{\Lambda }=0.65$ GeV and ${\lambda }_1=-0.71$ GeV${}^2$.

Comments: IR renormalon ambiguity is included