The 43rd International Symposium on Lattice Field Theory (Lattice 2026)

$B_{(s)} \to D_{(s)} \ell \nu$ with Highly Improved Staggered Quarks

30 Jul 2026, 17:10

20m

Pyon Su (Adele H. Stamp Student Union)

Contributed talk Quark and lepton flavor physics Quark and lepton flavor physics

Speaker

Akhil Chauhan (University of Illinois Urbana Champaign)

Description

We present a calculation of the form factors for $B_{(s)} \to D_{(s)} \ell \nu$ decay using the highly improved staggered quark action for both valence and sea quarks on the MILC collaboration’s $2+1+1$-flavor ensembles. We use 9 ensembles with lattice spacings ranging from 0.09fm to 0.03fm, 3 of which have physical pion masses. On our finest ensembles, we compute the form factors directly at the physical $b$-quark mass. In this talk, we present blinded results of our form factors in the continuum limit at the physical point. We present error budgets including statistical and systematic errors. For $B \to D$ we combine our results with experimental data to obtain blinded results for $|V_{cb}|$ and $R(D)$.