相关论文: $B\to D^{(\ast)}\ell\nu$ at non-zero recoil

Lattice calculation of $B\to D^{(*)}\ell\bar\nu$ decay form factors is now available from multiple lattice collaborations for both zero-recoil limit and non-zero recoil kinematics. Yet, there are a number of challenges we face to better…

We present results of a lattice QCD calculation of $B\to D^*$ and $B_s\to D_s^*$ axial vector matrix elements with both states at rest. These zero recoil matrix elements provide the normalization necessary to infer a value for the CKM…

We re-examine the determination of $|V_{cb}|$ from $B\to D \ell \nu$ in view of recent experimental and theoretical progress, discussing the parameterization of the form factors and studying the role played by the unitarity constraints. Our…

Lattice QCD (LQCD) calculations play a key role in the establishment of flavor anomalies. One of the most recent advancements in LQCD to this end has been the publication of several calculations of the $B\to D^\ast\ell\nu$ form factors, but…

We present the first unquenched lattice-QCD calculation of the hadronic form factors for the exclusive decay $\overline{B} \rightarrow D \ell \overline{\nu}$ at nonzero recoil. We carry out numerical simulations on fourteen ensembles of…

We update the lattice calculation of the $B\to\pi$ semileptonic form factors, which have important applications to the CKM matrix element $|V_{ub}|$ and the $B\to\pi\ell^+\ell^-$ rare decay. We use MILC asqtad ensembles with $N_f=2+1$ sea…

In addition to the well-known $B \to D^{(*)} \ell \nu_\ell$ decays, semileptonic $B_s \to D_s^{(*)} \ell \nu_\ell$ processes offer the possibility to determine the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $\vert V_{cb}\vert$. We…

The measured $\bar{B}\to D^{(*)} l \bar\nu$ decay rates for light leptons ($l=e,\mu$) constrain all $\bar{B}\to D^{(*)}$ semileptonic form factors, by including both the leading and ${\cal O}(\Lambda_{\text{QCD}}/m_{c,b})$ subleading…

We use HPQCD's recent lattice QCD determination of $B \to K$ scalar, vector and tensor form factors to determine Standard Model differential branching fractions for $B \to K \ell^+\ell^-$, $B\to K \ell_1^+\ell_2^-$ and $B \to K\nu…

We present HPQCD's improved scalar, vector and tensor form factors for $B \to K$ semileptonic decays, using the heavy-HISQ formalism for more accurate normalisation of the weak currents. Working with masses close to the physical $b$ on the…

In light of prospects for measurements of $B_c \rightarrow D^{(\ast)} l \nu$ decays in the upcoming Upgrade II of the LHC, we show that by using calculated $B_c \rightarrow D^{(\ast)}$ form factors competitive extraction of the $|V_{ub}|$…

We show how to extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $\vert V_{cb} \vert$ from exclusive semileptonic $B \to D^{(*)}$ decays by using the Dispersive Matrix (DM) method. It is a new approach which allows to determine in…

Semileptonic $B_{(s)}$ decays are of great phenomenological interest because they allow to determine e.g. CKM matrix elements or test lepton flavor universality. Taking advantage of already existing lattice data, we demonstrate the analysis…

We report on a two-flavour lattice QCD study of the $B_s \to D_s$ and $B_s \to D^*_s$ transitions parameterized, in the heavy quark limit, by the form factors ${\cal G}$, and $h_{A_1}$, $h_{A_2}$ and $h_{A_3}$, respectively. In the search…

This talk covers recent theoretical progress in exclusive semileptonic rare B-decays at low hadronic recoil. The efficient parametric suppression of the 1/mb corrections in this region provides opportunities to probe the Standard Model and…

Semi-leptonic $B$ decays provide promising channels to test the Standard Model, search for signs of new physics, or determine fundamental parameters like CKM matrix elements. We present an update on our calculation of short distance…

The search for New Physics (NP) beyond the Standard Model (SM) has been a central focus of particle physics, including in the context of $B$-meson decays involving $b \to s \ell \ell$ transitions. These transitions, mediated by…

In recent years, exciting (indirect) hints for physics beyond the Standard Model (SM) have been accumulated. In particular, semi-leptonic $B$ decays show deviations from the SM predictions, which, due to the ratios $R(K^{(*)})$ and…

Data in $B$-meson decays indicate violations of lepton flavour universality, thereby raising the question about such phenomena in the charm sector. We perform a model-independent analysis of NP contributions in (semi)-leptonic decays of…

We calculate the $B \to D^{(*)} \ell \nu$ form factors in 2+1 flavor relativistic lattice QCD by employing the M\"obius domain-wall action for all quark flavors. Our simulations are carried out at lattice cut-offs $a^{-1} \sim 2.5$, 3.6 and…