Differential decay rate for $B \to πl ν$ semileptonic decays

Abstract

We present our study on $B \to πl ν$ semileptonic decay form factors with NRQCD action for heavy quark from a quenched lattice QCD simulation at $β$=5.9 on a $16^3\times 48$ lattice. We obtain form factors defined in the context of heavy quark effective theory by Burdman et al. and find that their $1/m_B$ correction is small. The limit of physical heavy and light quark masses can be performed without introducing any model function, and we obtain a prediction for the differential decay rate $dΓ/dq^2$. We also discuss the soft pion limit of the form factors.

Lattice 2000, 4 pages, 4 figures, Latex