Related papers: Zero-Recoil Sum Rules for $\Lambda_b \to \Lambda_c…

The $b \to c$ semileptonic sum rules provide relations between the decay rates of $B \to D^{(*)} \tau\bar\nu$ and $\Lambda_b \to \Lambda_c \tau\bar\nu$. Starting from the heavy quark and zero-recoil limits, we revisit the derivation of the…

The zero recoil limit of the B -> D l nu form factors is calculated on the lattice, which provides a model-independent determination of |Vcb|. Considering a ratio of form factors, in which the bulk of statistical and systematic errors…

We examine the B -> D* form factor at zero recoil using a continuum QCD approach rooted in the heavy quark sum rules framework. A refined evaluation of the radiative corrections as well as the most recent estimates of higher order power…

Comparing the result of inserting a complete set of physical states in a time ordered product of $b$ decay currents with the operator product expansion gives a class of zero recoil sum rules. They sum over physical states with excitation…

In this work, the full leading order results of the form factors for $\Xi_{b}\to\Xi_{c}$ and $\Lambda_{b}\to\Lambda_{c}$ are obtained in QCD sum rules. Contributions from up to dim-5 have been considered. For completeness, we also study the…

We present an update of our calculation of the form factor for B -> D* l nu at zero recoil, with higher statistics and finer lattices. As before, we use the Fermilab action for b and c quarks, the asqtad staggered action for light valence…

We describe a model independent lattice QCD method for determining the deviation from unity for h_{A1}(1), the B -> D* l nu form factor at zero recoil. We extend the double ratio method previously used to determine the B -> D l nu form…

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 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…

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 provide upper and lower bounds on the semileptonic weak decay form factors for $B \to D^(*)$ and $\Lambda_b \to \Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order…

The current status of the lattice-QCD calculations of the form factors of the $B\to D^\ast\ell\nu$ semileptonic decay is reviewed. Particular emphasis is given to the most mature calculation at non-zero recoil coming from the Fermilab…

We consider the small velocity sum rules for heavy flavour semileptonic transitions that are used to estimate the zero recoil values of semileptonic heavy flavour form factors. We analyze the complete O($\alpha _S$) radiative correction to…

In this work, we calculate the transition form factors of $\Lambda_b$ decaying into $\Lambda_c$ within the framework of light-cone sum rules with the distribution amplitudes (DAs) of $\Lambda_b$-baryon. In the hadronic representation of the…

Lattice QCD can contribute to the search for new physics in b -> s decays by providing first-principle calculations of B -> K(*) form factors. Preliminary results are presented here which complement sum rule determinations by being done at…

We present the first lattice QCD calculation of the form factor for B-> D* l nu with three flavors of sea quarks. We use an improved staggered action for the light valence and sea quarks (the MILC configurations), and the Fermilab action…

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…

The form factors of the semileptonic $B_{q}\to D_{q}(J^{P}=0^{-})\ell\nu$ with $q=s, u, d$ transitions are calculated in the framework of three point QCD sum rules. Using the $q^2$ dependencies of the relevant form factors, the total decay…

In this article, the electroweak transition form factors of $\Lambda_b\to\Lambda_c$ and $\Xi_b\to\Xi_c$ are analyzed within the framework of three-point QCD sum rules. In phenomenological side, all possible couplings of interpolating…

The rare baryonic decays $\Lambda_b \to \Lambda \mu^+ \mu^-$ and $\Lambda_b \to \Lambda \gamma$ can complement rare $B$ meson decays in constraining models of new physics. In this work, we calculate the relevant $\Lambda_b \to \Lambda$…