Related papers: On the four-quark operator matrix elements for the…
The problem of the $\Xi_{c}^{+}$ lifetime is considered in the framework of {\em Heavy-Quark Expansion} and $SU(3)_{flavor}$ symmetry. The lifetime of $\Xi_{c}^{+}$ is expressed in terms of measurable inclusive quantities of the other two…
We discuss how the peculiar properties of maximally twisted Wilson fermions can be exploited to set up a consistent LQCD computational scheme in which the CP-conserving matrix elements of the $\Delta S =1,2$ effective weak Hamiltonian can…
Kolya Uraltsev was one of the inventors of the Heavy Quark Expansion (HQE), that describes inclusive weak decays of hadrons containing heavy quarks and in particular lifetimes. Besides giving a pedagogic introduction to the subject, we…
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…
I identify a source of \Lambda_{QCD}/m_Q corrections to the assumption of quark-hadron duality in the application of heavy quark methods to inclusive heavy quark decays. These corrections could substantially affect the accuracy of such…
We use the QCD sum rule approach to calculate the splitting between vector and pseudoscalar mesons containing one light and one heavy quark, and the kinetic energy of the heavy quark. Our result for the splitting induced by the…
We study the lifetimes and inclusive semileptonic decay widths of doubly heavy baryons within the framework of heavy quark expansion. Our analysis includes next-to-leading-order corrections to the dimension-3, -5, and -6 operators, together…
We consider the Heavy Quark Expansion (HQE) for the nonleptonic decay rates of heavy hadrons, and compute the NLO QCD corrections to power terms up to order $1/m_Q^2$. We neglect the masses of the final-state quarks, so the application of…
We calculate expectation values of QCD operators consisting of the products of the four operators of the light quarks corresponding to the scalar, pseudoscalar, vector, pseudovector (axial) and tensor Lorentz structures in the nucleon. All…
We extend Voloshin's recent analysis of charmed and beauty hyperon decays based on SU(3) symmetry and heavy quark effective theory, by introducing a rather moderate model-dependence, in order to obtain more predictive power, e.g. the values…
We use QCD sum rules to compute matrix elements of the Delta B=2 operators appearing in the heavy-quark expansion of the width difference of the B_s mass eigenstates. Our analysis includes the leading-order operators Q and Q_S, as well as…
We study the lifetime and weak decays of the full-heavy S-wave $0^+$ tetraquark $T^{\{bb\}}_{\{\bar c\bar c\}}$. Using the operator product expansion rooted in heavy quark expansion, we find a rather short lifetime, at the order…
In the 1990s, very low experimental values for the lifetime ratio $\tau (\Lambda_b)/\tau(B_d)$ triggered a considerable amount of doubt in the applicability of the heavy quark expansion (HQE), which is based on the assumption of…
The harmonic quarks are applied to the analysis of quark structures of long-lived $D$-mesons and $\psi/J$. In the harmonic quark model the quarks of long-lived mesons ($\pi^0$, $\pi^\pm$, $K^\pm$, $K^0$, $B^0$, $B^\pm$) are weakly…
We present a lattice QCD calculation of the heavy quark expansion parameters $\mu_{\pi}^2$ and $\mu_G^2$ for heavy-light mesons and heavy-light-light baryons. The calculation is carried out on a 20$^3\times$48 lattice at $\beta$ = 6.0 in…
The effects of spectator light quark in decays of heavy mesons are considered, which vanish in the limit of factorization of matrix elements of four-quark operators over the mesons. These effects include the difference of the total widths…
The lifetime splitting between the B^+ and B_d^0 mesons has recently been calculated in the next-to-leading order of QCD. These corrections are necessary for a reliable theoretical prediction, in particular for the meaningful use of…
We match continuum and lattice heavy-light four-fermion operators at one loop in perturbation theory. For the heavy quarks we use nonrelativistic QCD and for the massless light quarks the highly improved staggered quark action. We include…
In this work, we analyze the semileptonic decay processes of $\Lambda_b \to \Lambda_c$ in the light-cone sum rule approach. In order to calculate the form factors of the $\Lambda_b$ baryon transition matrix element, we use the light-cone…
The Lambda_b to Lambda_c semileptonic decay is analyzed in the framework of heavy quark effective theory to the order of 1/m_c and 1/m_b. The QCD sum rule and large N_c predictions to the decay form factors are applied. It argues that the…