### Speaker

Mr
Judd Harrison
(Department of applied mathematics and theoretical physics, University of Cambridge)

### Description

We present our recent calculation of the zero-recoil form factor for the semileptonic decay $\bar{B}^0\rightarrow D^{*+} \ell^- \bar{\nu} $ using lattice QCD with 2+1+1 flavours of highly improved staggered quarks in the sea (the MILC HISQ configurations) and using non-relativistic QCD for the bottom quark. We obtain $\mathcal{F}(1)$ and combine this with the latest HFAG average of $\eta_{EW} \mathcal{F}(1) |V_{cb}|$ to get a value for $|V_{cb}|$.

### Primary author

Mr
Judd Harrison
(Department of applied mathematics and theoretical physics, University of Cambridge)

### Co-authors

Prof.
Christine Davies
(University of Glasgow)
Dr
Matthew Wingate
(University of Cambridge)