Perturbative and Non-perturbative Corrections to $B\to D^{(\ast )}l\nu$

Abstract

It is shown that certain double ratios introduced for computing semileptonic form factors are accurate to order $1/m_Q^2$, even when the action and current are accurate to order $1/m_Q$.

Comments: Lattice99(heavyquarks); 3 + epsilon pp. LaTeX