相关论文: Remarks on Semileptonic B and D Decays into Orbita…
We present a study of B decays into semileptonic final states containing charged and neutral $D_1(2420)$ and $D_2^*(2460)$. The analysis is based on a data sample of $208 fb^{-1}$ collected at the $\Upsilon(4S)$ resonance with the BaBar…
In this note, recent results of studies of semileptonic B meson decays from \babar are discussed and preliminary results given. In particular, a recent measurement of $\mathcal{B}(B \to D^{(*)}\tau \nu)$ and the ratio $\mathcal{B}(B \to…
We report a study of semileptonic B decays to P-wave D** mesons. Semileptonic decay to D*_2 meson is observed for the first time and its product branching ratio is measured to be Br(B+ -> anti-D*0_2 l+nu) x Br(anti-D*0_2 -> D- pi+) = 0.22…
We have studied semileptonic $B$ meson decays with a P-wave charm meson in the final state using 3.29 x 10^6 B\bar{B} events collected by the CLEO~II detector at the Cornell Electron-positron Storage Ring. We find a value for the exclusive…
We report on a measurement of the charmless semileptonic B decays, B0->pi^-l^+nu and B0->rho^-l^+nu, based on 140 fb^{-1} data collected with the Belle detector at the KEKB e^+e^- asymmetric collider. In this analysis, accompanying B mesons…
A relativistic quark model is applied to the description of semileptonic and non-leptonic charmed decays of the B-meson. The exclusive semileptonic modes B -> D l \nu and B -> D* l \nu are described through the universal Isgur-Wise form…
We report the results of a study of the exclusive semileptonic decays B->pi0lnu, B->pi+lnu, B->rho0lnu, B->rho+lnu and B->omegalnu, where l represents an electron or a muon. The events are tagged by fully reconstructing a second B meson in…
In this paper, we study the $B \to D^{(*)} l^- \bar{\nu}_{\rm l}$ semileptonic decays and calculate the branching ratios ${\cal B}(B \to D^{(*)} l^- \bar{\nu}_{\rm l})$ and the ratios $R(D^{(*)})$ and $R_{\rm D}^{\rm l,\tau}$ by employing…
The BaBar Collaboration has recently reported products of branching fractions that include $B$ meson semileptonic decays into final states with charged and neutral $D_{1}(2420)$ and $D_{2}^{\ast}(2460)$, two narrow orbitally excited charmed…
The semileptonic decays $\bar{B}\to D(D^*)\pi\ell\bar{\nu}$ are analyzed by heavy quark and chiral symmetries. The branching ratio is of order of a few percent for $\dpi$, but it is much smaller for $\dstar$, of order $10^{-4}-10^{-5}$. The…
The $\bar{B}_s^0 \to D_s^{(*)+} l^- \bar{\nu}_l$ semileptonic decays were calculated in the framework of the standard model (SM) by employing the perturbative QCD (pQCD) factorization approach. We defined four ratios of the branching ratios…
We report a measurement of the ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal B}(\bar{B}^0 \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or a muon. The results…
We investigate the radiative dileptonic decays $B_s(B_d)\to\gamma l^+l^-$ within the standard model. Using the constituent quark model, the branching ratios turn out to be around $5\times 10^{-9}$ for $B_s\to \gamma \mu^+\mu^- $ and around…
Branching ratios and polarization amplitudes for B decaying to all allowed pseudoscalar, vector, axial-vector, scalar and tensor combinations of D_s and D mesons are calculated in the Isgur Scora Grinstein Wise (ISGW) quark model after…
We present here three analyses of semileptonic $D$-meson decays based on the 2.92 fb$^{-1}$ of data collected by the BESIII experiment in 2010 and 2011 at the $\psi$(3770) peak. For the decay $D^{+}\to K^{-}\pi^{+}e^{+}\nu_{e}$, its…
We report a measurement of the charmless semileptonic decays $B^0 \to \pi^- / \rho^- \ell^{+} \nu$ and $B^+ \to \pi^0 / \rho^0 \ell^{+} \nu$, based on 253 fb$^{-1}$ of data collected with the Belle detector at the KEKB $e^+e^-$ asymmetric…
We report a measurement of ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal B}(\bar{B}^0 \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or a muon. The results are…
We study exclusive nonleptonic and semileptonic decays of the Bc-meson within a relativistic constituent quark model previously developed by us. For the nonleptonic decays we use the factorizing approximation. We update our model parameters…
Semileptonic and leptonic B decays are analyzed in the framework of the relativistic quark model. Special attention is payed to the decays involving $\tau$ lepton. It is found that the calculated particular decay branching fractions are…
Exclusive semileptonic B decays to radially excited charmed mesons are investigated at the first order of the heavy quark expansion. The arising leading and subleading Isgur-Wise functions are calculated in the framework of the relativistic…