Speaker
Kay Schoenwald
(KIT)
Description
In this talk we present our recent calculation of order $\alpha_s^3$ corrections to the semi-leptonic $b\to c$ decay.
The calculation has been performed in an expansion around the heavy-daughter limit $m_c \sim m_b$, but also shows decent convergence for $m_c=0$. For the semi-leptonic $b\to c$ decay we find large perturbative corrections in the on-shell scheme which can be significantly reduced by changing to the kinetic scheme for the heavy quark masses. These results will be important input for the inclusive determination of $|V_{cb}|$ and the Fermi coupling constant $G_F$ in the future.
