Related papers: A Vademecum on Quark-Hadron Duality
We investigate the exclusive semileptonic $B_c\to (D,\eta_c,B,B_s)\ell\nu_\ell$, $\eta_b\to B_c\ell\nu_\ell$($\ell=e,\mu,\tau$) decays using the light-front quark model constrained by the variational principle for the QCD motivated…
We develop a systematic framework for exclusive rare B decays of the type B -> K(*)l+l- at large dilepton invariant mass q^2. It is based on an operator product expansion (OPE) for the required matrix elements of the nonleptonic weak…
Bloom-Gilman duality relates parton distributions to nucleon form factors and thus constrains the dynamics of exclusive processes. The quark electric charge dependence implies that exclusive scattering is incoherent on the quarks even at…
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…
Inclusive heavy-flavour decays can be described through $1/m_Q$ expansions derived from QCD with the help of an operator product expansion. I sketch their methodology and apply them first to semileptonic B decays; $|V(cb)|$ can be extracted…
We discuss why, in the determination of $\alpha_s(m_{\tau}^2)$ from hadronic $\tau$ decays, two important assumptions made in most of previous analyses, namely the neglect of higher-dimension condensates and of Duality Violations (DVs),…
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.…
The LHCb collaboration has very recently released a new study of $B^+ \to K^{+} \ell^+ \ell^-$ and $B \to K^{*0} \ell^+ \ell^-$ ($\ell = e,\mu$) decays, testing lepton universality with unprecedented accuracy using the whole Run 1 and 2…
Light front wave functions motivated by holographic constructions are used to study Bloom-Gilman duality of deep inelastic scattering. Separate expressions for structure functions in terms of quark and hadronic degrees of freedom are…
We discuss the possibility of extracting |V_{ub}| from various spectra of inclusive B decays, without large systematic errors which usually arise from having to model the Fermi motion of the heavy quark. This strategy can be applied to the…
The latest measurements of rare $b\to s$ decays in the LHCb experiment have led to results in tension with the predictions of the standard model (SM), including a tentative indication of the violation of lepton flavor universality. Assuming…
The exclusive rare decay $B \ra K^\ast \gamma$ takes place in a region of maximum recoil, $q^{2}=0$, posing a problem for nonrelativistic quark models which are usually thought to be most reliable at zero recoil. The Bauer--Stech--Wirbel…
We explore the application and usefulness of the heavy quark symmetry to describe the weak decays of hadrons (mesons and baryons) containing two heavy quarks. Firstly, we address the internal dynamics of a heavy-heavy bound system with the…
We introduce two approaches to analyses of Borel sum rules. In the first method, we take the Borel mass M2 to infinity. Here, the sum rules become very sensitive to the chosen threshold s0. We fix the threshold by setting the daughter sum…
We review the current status of theoretical predictions for mixing quantities and lifetimes in the $B$-sector. In particular, due to the first non-zero measurement of the decay rate difference in the neutral $B_s$-system, $\Delta \Gamma_s/…
We present precision corrections to dispersion relation bounds on form factors in bottom hadron semileptonic decays and analyze their effects on parameterizations derived from these bounds. We incorporate QCD two-loop and nonperturbative…
The following is an overview of the measurements of the CKM matrix elements V_cb and V_ub that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and recent advances in QCD calculations. In…
Strong interactions are addressed in connection to extracting |V_{cb}| and determining heavy quark parameters. A comprehensive approach allows a robust analysis not relying on a 1/m_c expansion; a percent defendable accuracy in |V_{cb}|…
This review addresses the question of the chirality of $b$ quark weak couplings from a theoretical and from a purely phenomenological point of view. Due to their small magnitude $b$ decay couplings are subject to possible large corrections…
Using recent results for nonperturbative contributions to the $B$ and $D$ meson inclusive semileptonic widths, a model independent extraction of $\vbc$, $m_c$ and $m_b$ is made from the experimentally measured $B$ and $D$ lifetimes and…