Related papers: Theoretical Uncertainties in Gamma_sl(b->u)
I describe the theoretical progress in the study of semileptonic tree-level B decays, and its interplay with recent experimental results. In particular, I focus on two anomalies: the ratios $R(D^{(*)})=\displaystyle\frac{{\cal B}(B \to…
The semileptonic B-> Xu l nu decays allow a pretty clean determination of the CKM matrix element |Vub|. Nevertheless, the presence of weak-annihilation effects near the end-point of the q2 spectrum introduces uncertainties in the inclusive…
The collection of a few anomalies in semileptonic $B$-decays, especially in $b\rightarrow c \tau \bar{\nu}$, invites to speculate about the emergence of some striking new phenomena, perhaps interpretable in terms of a weakly broken $U(2)^n$…
We summarize the status of $|V_{cb}|$ and $|V_{ub}|$ determinations, including the long standing tension among exclusive and inclusive determinations. We also discuss $B$ meson semileptonic decays to excited states of the charm meson…
Utilizing asymptotic Pade-approximant methods, we estimate the three-loop order MS-bar coefficients of alpha_s^3[\log(\mu^2/m^2_b(\mu)]^k terms [k = {0,1,2,3}] within the $b \to u\ell^-\bar{\nu}_\ell$ decay rate. Except for the coefficient…
We analyze uncertainties in the theoretical prediction for the inclusive branching ratio $BR[B \rightarrow X_s \gamma]$. We find that the dominant uncertainty in the leading order expression comes from its $\mu$-dependence. We discuss a…
We present a lattice quantum chromodynamics determination of the ratio of the scalar and vector form factors for two semileptonic decays of the $B_s$ meson: $B_s \rightarrow K \ell \nu$ and $B_s \rightarrow D_s \ell \nu$. In conjunction…
The non-factorizable terms in the operator product expansion have been recognized as one of theoretical obstacles for precision determination of the mixing parameter $V_{ub}$ from semileptonic B decays. It is pointed out here that the…
We comment on two recent calculations of the second order perturbative corrections in the heavy flavor semileptonic transitions within the Brodsky-Lepage-Mackenzie approach. It is pointed out that the results do not show significant…
A precise determination of |V_{ub}| can be obtained exploiting the sum rule for inclusive charmless semileptonic B-meson decays. The sum rule is derived on the basis of light-cone expansion and b-flavored quantum number conservation. The…
Recent results on inclusive and exclusive semileptonic B decays from B Factories are presented. The status and perspectives of the determination of the CKM matrix elements Vub and Vcb with semileptonic B decays is discussed.
Recent progress in calculating O(alpha_s^2) corrections to inclusive and exclusive semileptonic b-->c transitions is reviewed. The impact of these corrections on the |V_cb| determination from both inclusive and exclusive B decays is…
The decay distribution of the kinematic variable \xi_u in inclusive charmless semileptonic decays of B mesons is unique. The novel method for a model-independent determination of |V_{ub}| is described.
Recent measurements of semileptonic $B$-meson decays into $\tau$-leptons are somewhat higher than expected in the standard model. Although the deviations are less than 3$\sigma$, they suggest the possibility of new physics affecting…
Superallowed $0^+\rightarrow 0^+$ transitions between $T=1$ nuclei have been a perfect avenue avenue for determining the Cabibbo-Kobayashi-Maskawa matrix element $V_{ud}$, which imposes powerful constraints on physics beyond the Standard…
Current methods of determining V_ub are dominated by theoretical uncertainties. We present Monte Carlo simulations of three promising methods of determining V_ub with small theoretical and experimental errors. We find that with data samples…
We investigate rare semileptonic \bar B -> \bar K^* l^+ l^- decays, providing a comprehensive treatment of theoretical uncertainties in the low-q^2 region as needed for interpreting current and future LHCb and B-factory data in terms of the…
We reconsider the prediction of the semileptonic branching ratio of B mesons, using a recent calculation of the radiative corrections with account for finite quark masses in nonleptonic decays and taking into account 1/m_b^2 corrections.…
We determine $|V_{cb}|$ from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate from the running of the strong coupling. We argue that the low value of the BLM scale found…
We present a measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic limit for B->X_c e\nu transitions, using a sample of 88 million Upsilon(4S) decays recorded by the BABAR detector. Partial…