B -> D* l nu with 2+1 flavors

TL;DR

This paper calculates the B to D* l nu decay form factor using advanced lattice QCD techniques with improved actions for light and heavy quarks, employing a novel double ratio method at zero recoil.

Contribution

It introduces a new double ratio method for more direct and precise calculation of the form factor at zero recoil in B to D* l nu decays.

Findings

Form factor computed at zero recoil with improved accuracy.

Utilizes 2+1 flavor MILC configurations and Fermilab action.

Demonstrates the effectiveness of the double ratio method.

Abstract

We present a calculation of the form factor for B -> D* l nu using a 2+1 improved staggered action for the light quarks (on the MILC configurations), and the Fermilab action for the heavy quarks. The form factor is computed at zero recoil using a new double ratio method which yields the form factor more directly than previous approaches.