相关论文: Application of M\"ossbauer-Type Sum Rules for $B$ …
The form factors of weak decays of $B_s$ mesons to ground state $D_s^{(*)}$ mesons as well as to their radial $D_s^{(*)}(2S)$ and orbital $D_{sJ}^{(*)}$ excitations are calculated in the framework of the relativistic quark model based on…
We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the…
Rare semileptonic decays of B and B_c mesons are investigated in the framework of the QCD-motivated relativistic quark model based on the quasipotential approach. Form factors parametrizing the matrix elements of the weak transitions…
B meson rare decays ($B\to K(K^{*})l\bar l$ and $B\to K^*\gamma$) are analyzed in the framework of effective field theory of heavy quarks. The semileptonic and penguin type form factors for these decays are calculated by using the light…
We investigate the $b\to c$ semileptonic sum rule in the presence of a massive sterile neutrino. Recent measurements of charged-current semitauonic $B$-meson decays exhibit a $\sim4\sigma$ deviation from the Standard Model predictions,…
We explicitly check quark-hadron duality to order $(m_b-m_c)\Lambda/m_b^2$ for $b \to c l\nu$ decays in the limit $m_b-m_c \ll m_b$ including ground state and orbitally excited hadrons. Duality occurs thanks to a new sum rule which…
The form factors of semileptonic $B_{(s)}\to a_{1}(K_1)\, \ell^{+}\ell^{-}$, $ \ell=\tau,\mu,e$ transitions are investigated in the framework of the light-cone sum rules with $B$-meson distribution amplitudes, which play an important role…
In the framework of the heavy quark effective theory, the leading order Isgur-Wise functions relevant to semileptonic decays of the orbitally $P$-wave excited $B_{s}$ meson states $B^{**}_{s}$, including the newly found narrow…
We study semileptonic sum rules for $b \to c \tau \overline{\nu}$ transitions involving orbitally excited charm hadrons. Starting from the amplitude-level relation implied by the heavy quark symmetry, we construct sum rules relating these…
The form factors relevant to $B_{q}\to D^{\ast}_{q}(J^{P}=1^{-}) ell\nu$ $(q=s, d, u)$ decays are calculated in the framework of the three point QCD sum rules approach. The heavy quark effective theory prediction of the form factors as well…
In the framework of three-point QCD sum rules, the form factors for the semileptonic decays of B_c^+ -> B_s(B_s^*) l \nu are calculated with account for the Coulomb-like alpha_s/v-corrections in the heavy quarkonium. The generalized…
The propagation and decay of neutral B-mesons can be described in terms of quantum dynamical semigroups; they provide generalized time-evolutions that take into account possible non-standard effects leading to loss of phase coherence and…
Applications of QCD sum rules to exclusive decays of heavy mesons are reviewed. In detail, we discuss the calculations of the B and $D$ decay constants, the heavy-to-light form factors $f^+(p^2)$ and $f^0(p^2)$, and the strong couplings…
Exclusive semileptonic decays of $B$ mesons to the ground, radially and orbitally excited states of light mesons are investigated in the framework of the relativistic quark model based on the quasipotential approach. Such decays are very…
B --> rho l nu decay is analyzed in the effective theory of heavy quark with infinite mass limit. The matrix element relevant to the heavy to light vector meson semileptonic decays is parametrized by a set of four heavy flavor-spin…
We derive two model-independent sum rules relating the transition matrix elements for radiative and strong decays of excited heavy mesons to properties of the lowest-lying heavy mesons. The sum rule for the radiative decays is an analog of…
We underline a problem existing in the heavy quark limit of QCD concerning the rates of semileptonic B decays into P-wave $D_J(j)$ mesons, where $j = {1 \over 2}$ (wide states) or $j = {3 \over 2}$ (narrow states). The leading order sum…
Semileptonic and nonleptonic decays of the B_c meson to charmonium and D mesons are studied in the framework of the relativistic quark model. The decay form factors are explicitly expressed through the overlap integrals of the meson wave…
Lepton flavor universality is a key prediction of the Standard Model of particle physics and any violation of it immediately indicates the existence of new physics. Given the recent more than $4\sigma$ discrepancy in charged current…
B decay sum rules relate exclusive B semileptonic decay matrix elements to forward B-meson matrix elements of operators in HQET. At leading order the operators that occur are the b-quark kinetic energy $\lambda_1$ and chromomagnetic energy…