Related papers: Nonspectator Effects and B Meson Lifetimes
Heavy quark expansion can nicely explain the lifetime of $\Lambda_{b}$. However, there still exist sizable uncertainties from the four-quark operator matrix elements of $\Lambda_{b}$ in $1/m_{b}^{3}$ corrections, which describe the…
We compute the matrix elements of the operators which contribute to spectator effects in inclusive decays of $B$-mesons. The results agree well with estimates based on the vacuum saturation (factorization) hypothesis. For the ratio of…
The difference of \tau_{_B} and \tau_{_{\Lambda_b}} indicates the role of the light flavors. We calculate the lifetimes of B-meson and \Lambda_b based on the weak effective Hamiltonian while assuming the heavy baryon is constructed by a…
$B_d$ and $B_s$ meson systems play a fundamental role to test and improve our understanding of Standard Model flavor dynamics. The mixing parameters $\Delta m_{d,s}$ represent important constraints in the unitarity triangle analysis. Their…
Estimates of lifetimes and partial branching ratios for the baryons $\Xi_{bc}^{+}$ and $\Xi_{bc}^{0}$ are presented using the inverse heavy quark mass expansion technique carried out in the Operator Product Expansion approach. We take into…
The Standard Model prediction of the $B_c$ lifetime is discussed, together with the dominant uncertainties and strategies on how to improve them. Furthermore, a new method to compute the $B_c$ lifetime based on the operator product…
Using an operator product expansion (OPE) approach an updated Standard Model prediction of the $B_c$ lifetime is presented. The computation in three different mass schemes for the heavy quarks leads to three different values consistent with…
The Standard Model prediction of the $B_c$ lifetime is discussed, together with the dominant uncertainties and strategies on how to improve them. Furthermore, a new method to compute the $B_c$ lifetime based on the operator product…
We present updated predictions for the lifetimes of all weakly decaying doubly heavy baryons, including $bb$, $cc$, and $bc$ baryons, as well as for the $B_c$ meson. The analysis includes NNLO corrections to the leading dimension-three…
Theoretical predictions of beauty hadron lifetimes, based on the heavy quark expansion up to and including order 1/mb^2, do not to reproduce the experimental measurements of the lifetime ratios tau(B+)/tau(Bd) and tau(Lambdab)/tau(Bd).…
The motion of spectator quarks in decay of a beauty hadron is a nonperturbative effect which can usually be neglected. We find that the motion in some decay channels, which contribute total decay widths of beauty hadrons, can not be…
We develop perturbative QCD factorization theorems for inclusive b-hadron decays, in which radiative corrections characterized by the hadronic scale, the b-hadron mass, and the W boson mass are absorbed into a heavy hadron distribution…
The QCD-based operator-product-expansion technique is systematically applied to the study of charmed meson lifetimes. We stress that it is crucial to take into account the momentum of the spectator light quark of charmed mesons, otherwise…
We compute perturbative QCD corrections to the lifetime splitting between the charged and neutral $B$ meson in the framework of the heavy quark expansion. These next-to-leading logarithmic corrections are necessary for a meaningful use of…
The Heavy Quark Expansion (HQE) gives an expansion of inclusive decay rates of $b$-hadrons as a simultaneous series in $\alpha_s$ and $1/m_b$, in terms of perturbatively defined coefficients and non-perturbative matrix elements. Spectator…
We investigate the total inclusive decay rate of the (ground state) $B_c$ meson within the framework of an operator product expansion in inverse powers of the heavy quark masses and subsequent matching onto nonrelativistic QCD. The…
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…
B-hadron physics plays a fundamental role to test and improve our understanding of flavor dynamics within and beyond the Standard Model. Of particular phenomenological interest are beauty hadron lifetime ratios and, width differences and…
We compute next-to-next-to-leading order QCD corrections to the partonic processes $b\to c \bar{u} d$ and $b\to c \bar{c} s$, which constitute the dominant decay channels in standard model predictions for $B$-meson lifetimes within the…
I discuss the heavy quark expansion for the inclusive widths of heavy-light hadrons, which predicts quite well the experimental ratios of B_q meson lifetimes. As for $\Lambda_b$, current determinations of ${\cal O}(m_b^{-3})$ contribution…