Form factors in the ${\mathrm{B}}_{\mathrm{s}}\to \mathrm{K}\ell \nu$ decays using HQET and the lattice

Abstract

We report on a recent computation of the form factors in semi-leptonic decays of the ${\mathrm{B}}_{\mathrm{s}}$ using Heavy Quark Effective Theory (HQET) formalism applied on the lattice. The connection of the form factors with the 2-point and 3-point correlators on the lattice is explained, and the subsequent non-perturbative renormalization of HQET and it's matching to $N_f=2$ QCD is outlined. The results of the (static) leading-order calculation in the continuum limit is presented.

Comments: On behalf on the ALPHA collaboration. Proceedings contribution to 34th annual International Symposium on Lattice Field Theory