Leptonic B- and D-meson decay constants with 2+1 flavors of asqtad fermions

Understand

We present the status of our updated D- and B-meson decay-constant analysis, based on the MILC $N_f = 2+1$ asqtad gauge ensembles.

• Heavy quarks are incorporated using the Wilson clover action with the Fermilab interpretation.
• This analysis includes ensembles at five lattice spacings from a $\approx$ 0.045 to 0.15 fm, and light sea-quark masses down to 1/20th of the strange-quark mass.
• Projected error budgets for ratios of decay constants, in particular between bottom- and charm-meson decay constants, are presented.