Related papers: $B \to D^{**}$ -- puzzle 1/2 vs 3/2
We propose a method to compute the Isgur-Wise form factors tau_1/2(1) and tau_3/2(1) for the decay of B mesons into orbitally excited (P wave) D** charmed mesons on the lattice in the static limit. We also present the result of an…
We use QCD sum rules to estimate the universal form factors describing the semileptonic B decays into excited charmed resonances, such as the $1^-$ and $2^-$ states $D_1^{*}$ and $D_2^{*}$ belonging to the $s_\ell^P={3/2}^-$ heavy quark…
Disentangling New Physics effects from the Standard Model requires a good understanding of all pieces that stem from the latter, especially the uncertainties that might plague the theoretical estimations within the Standard Model. In the…
Precise theoretical predictions derived from the Standard Model are a key ingredient in searches for new physics in the flavor sector. The large mass and long lifetime of the $b$ quark make processes involving $b$ quarks of particular…
We report on our calculation of the B \to D^(*) \ell \nu form factors in 2+1 flavor lattice QCD. The M\"obius domain-wall action is employed for light, strange, charm and bottom quarks. At lattice cutoffs 1/a \sim 2.4, 3.6 and 4.5 GeV, we…
We propose studying the mechanism of factorization in exclusive decays of the form B->D(*)X by examining the differential decay rate as a function of the invariant mass of the light hadronic state X. If factorization works primarily due to…
A phenomenological analysis based on the published branching fractions and $CP$ asymmetry observables of the $B\to K\pi$, $B\to\pi\pi$ and $B\to KK$ dataset is performed. The amplitude decomposition by the topological diagrams and the…
The semi-leptonic $b \to c l \nu$ processes are receiving a lot of attention, as the lepton flavor universality violation has been hinted by the measured ratios $R_{D^{(*)}} = \Gamma(B \to D^{(*)} \tau\nu)/\Gamma(B \to D^{(*)} \ell\nu)$ for…
Semi-leptonic $B_s \to K \ell \nu$ and $B_s \to D_s \ell \nu$ decays provide an alternative $b$-decay channel to determine the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$ or to obtain $R$-ratios to investigate lepton flavor universality…
The present status of lattice calculations of f_B, B_B and SU(3) flavour breaking ratios such as f_Bs/f_B is reviewed. Particular attention is devoted to systematic uncertainties, such as those arising from the lack of simulation data for…
Lattice QCD should allow a derivation of the $\Delta I=1/2$ rule from first principles, but numerical calculations to date have been plagued by a variety of problems. After a brief review of these problems, we present several new methods…
In this article, we investigate the potential of the angular distribution of the $B \rightarrow D^* \ell {\nu}_{\ell}$ process to search for new physics signals. The Belle collaboration has analysed it to constraint $V_{cb}$ and the $B\to…
The mass and width of the lightest scalar open-charm state listed in the Review of Particle Physics, the $D_0^\ast(2300)$, are in puzzling tension with predictions from unitarized chiral perturbation theory (UChPT) and lattice QCD, which…
At present, there are several hints of lepton flavor non-universality. The LHCb Collaboration has measured $R_K\equiv{\cal B}(B^+ \to K^+ \mu^+ \mu^-)/{\cal B}(B^+ \to K^+ e^+ e^-)$, and the BaBar Collaboration has measured $R(D^{(*)})…
We perform a comprehensive analysis of scalar contributions in $b \to c \tau \nu$ transitions including the latest measurements of $R(D^{(*)})$, the $q^2$ differential distributions in $B \to D^{(*)} \tau \nu$, the $\tau$ polarization…
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…
Recent experimental measurements and lattice QCD calculations are now reaching the precision (and accuracy) needed to over-constrain the CKM parameters $\bar\rho$ and $\bar\eta$. In this brief review, I discuss the current status of lattice…
For a number of years, there has been a certain inconsistency among the measurements of the branching ratios and CP asymmetries of the four $B \to \pi K$ decays ($B^+ \to \pi^+ K^0$, $B^+ \to \pi^0 K^+$, $B^0 \to \pi^- K^+$, $B^0 \to \pi^0…
Recently, several indications of lepton non-universality observables have been perceived in semileptonic $B$ meson decay processes, both in the neutral-current ($b \to s ll $) and charged-current ($b \to c l \bar \nu_l$) transitions.…
We report on our determinations of $B\to \pi\ell\nu$, $B_s\to K \ell \nu$ and $B_s\to D_s \ell \nu$ semileptonic form factors. In addition we discuss the determination of $R$-ratios testing lepton-flavor universality and suggest an improved…