相关论文: Enhancement of the $\Lambda_b$ decay rate

Exclusive semileptonic Lambda_b decays to excited charmed Lambda_c baryons are investigated at order Lambda_{QCD}/m_Q in the heavy quark effective theory. The differential decay rates are analyzed for the J^\pi=1/2^- Lambda_c(2593) and the…

We suggest a new technique to determine the CKM phase $\gamma$ {\em without} neglecting the (soft) final state rescattering effects. We use (time integrated) $B$ meson decay rates to $\pi$'s and $K$'s. A set of 5 $\Delta S = 0$ (or 1…

We determine the relative branching fractions of semileptonic B decays to charmed final states. The measurement is performed on the recoil from a fully reconstructed B meson in a sample of 362 million BBbar pairs collected at the…

The first observation of the semileptonic $b$-baryon decay $ \Lambda_b^0 \rightarrow \Lambda_c^+ \tau^-\overline{\nu}_{\tau}$, with a significance of $6.1\,\sigma$, is reported using a data sample corresponding to 3 fb$^{-1}$ of integrated…

The sensitivity of the CKM angle $\gamma$ in $\Lambda_b^0 \to D \Lambda$ decays has been studied using the decay parameter $\alpha$ as an observable in addition to the decay rate asymmetry. Feasibility studies show that adding this…

The differential decay spectrum $d\Gamma/dE_e dq^2$ for the semileptonic decay of an unpolarized hadron containing a b-quark, and the decay spectrum $d\Gamma/dE_e dq^2 d\!\cos\theta$ for polarized $\Lambda_b$ decay are computed to second…

By analyzing $e^+e^-$ collision data taken at center-of-mass energies $\sqrt{s}$ between 4.600 and 4.699 GeV with the BESIII detector at the BEPCII collider, corresponding to an integrated luminosity of $\rm 4.5~fb^{-1}$, we study the…

We study the hadronic decays of $\Lambda_{c}^{+}$ to the final states $\Sigma^{+}\eta$ and $\Sigma^+\eta^\prime$, using an $e^{+}e^{-}$ annihilation data sample of 567 pb$^{-1}$ taken at a center-of-mass energy of 4.6 GeV with the BESIII…

Properties of single beauty baryons ($\Sigma_{b},\Lambda_{b}$) are studied based on the quark-diquark structure. The confinement potential is assumed as two body colour coulomb plus power potential with exponent $\nu$. We find a strong…

The three-body decay $B^0(B_s)\to \gamma\nu \bar{\nu}$ can occur via penguin and box diagrams in the standard model (SM). These channels are useful to determine the decay constants $f_B$ ($f_{B_s}$) and $B$ ($B_s$) meson wave function.…

The B_{s} --> \phi\psi decay is modeled through the inclusive b --> s\psi decay. Using the Vector Meson Dominance model, the amplitude for the chain process B_{s} --> \phi\psi --> \phi\gamma --> \gamma\gamma is estimated and it is found to…

Using fully reconstructed $B_{s}$ mesons, we measure exclusive branching fractions for the decays $B_s \to D_s^{(*)+}D_s^{(*)-}$. The results are ${\cal B}(B^0_s\ra D^+_s D^-_s)=(0.58\,^{+0.11}_{-0.09}\,\pm 0.13)%$, ${\cal B}(B^0_s\ra…

Using $(10087\pm 44)\times10^6$ $J/\psi$ events collected with the BESIII detector, we report the first observation of the electromagnetic radiative decays of the $\Lambda(1520)$ and $\Lambda(1670)$ to $\gamma\Sigma^0$, with a statistical…

We present an investigation of the decays $\bar{B}^0 \to \Lambda_{c}^{+} \bar{p}$ and $B^- \to \Lambda_{c}^{+} \bar{p} \pi^-$ based on $383\times10^6$ $\Upsilon(4S) \to B\bar{B}$ decays recorded with the BABAR detector. We measure the…

The (Delta I = 1) decay D_s^* --> Ds pi0 and (\Delta I = 0) decay D_s^* --> Ds gamma have been reconstructed using 90.4 fb^-1 of data recorded by the BaBar detector at the PEP-II asymmetric-energy e^+e^- collider. The relative branching…

The radiative decay $\Lambda_{b}^{0} \to \Lambda \gamma$ is observed for the first time using a data sample of proton-proton collisions corresponding to an integrated luminosity of $1.7\,fb^{-1}$ collected by the LHCb experiment at a…

We report the first observation of the radiative hyperonic B decay B+ -> p Lambdabar gamma, using a 140 fb^{-1} data sample recorded on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. The…

Based on a new, exact QCD factorization formula for the partial B->X_s+gamma decay rate with a restriction on large photon energy, improved predictions are presented for the partial moments <E_gamma> and <E_gamma^2>-<E_gamma>^2 of the…

Rare $\Lambda_b\to\Lambda l^+l^-$ and $\Lambda_b\to\Lambda\gamma$ decays are investigated in the relativistic quark model based on the quark-diquark picture of baryons. The decay form factors are calculated with the account of all…

We give a more complete calculation of $b \to s\gamma $ decay, including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. We have included the full set of dimension-6 operators and…