English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present a lattice QCD determination of the $B_s \to D_s \ell\nu$ scalarand vector form factors over the full physical range of momentum transfer. Theresult is derived from correlation functions computed using the Highly ImprovedStaggered Quark (HISQ) formalism, on the second generation MILC gluon ensemblesaccounting for up, down, strange and charm contributions from the sea. Wecalculate correlation functions for three lattice spacing values and an arrayof unphysically light $b$-quark masses, and extrapolate to the physical value.Using the HISQ formalism for all quarks means that the lattice current couplingto the $W$ can be renormalized non-perturbatively, giving a result free fromperturbative matching errors for the first time. Our results are in agreementwith, and more accurate than, previous determinations of these form factors.From the form factors we also determine the ratio of branching fractions thatis sensitive to violation of lepton universality: $R(D_s) = \mathcal{B}(B_s\toD_s \tau \nu_{\tau})/\mathcal{B}(B_s\to D_s \ell \nu_{l})$, where $\ell$ is anelectron or a muon. We find $R(D_s) = 0.2987(46)$, which is also more accuratethan previous lattice QCD results. Combined with a future measurement of$R(D_s)$, this could supply a new test of the Standard Model. We also comparethe dependence on heavy quark mass of our form factors to expectations fromHeavy Quark Effective Theory.

$B_s\to D_s \ell\nu$ Form Factors for the full $q^2$ range from Lattice QCD with non-perturbatively normalized currents