相关论文: First observation and branching fraction and decay…
Using a 281 pb^{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D^0 rightarrow K^-pi^+pi^-e^+nu_e at a statistical significance of about 4.0…
In an experiment designed to search for and study very rare two-body decay modes of the K-long, we have observed four examples of the decay K-long -> e+ e-, where the expected background is 0.17+-0.10 events. This observation translates…
The first observation of \chi_cJ (J=0,1,2) decays to Lambda Lambda-bar is reported using \psi(2S) data collected with the BESII detector at the BEPC. The branching ratios are determined to be BR(\chi_c0 \to Lambda Lambda-bar) =…
We present measurements of branching fractions and charge asymmetries for six B-meson decay modes with an eta or eta' meson in the final state. The data sample corresponds to 232 million BBbar pairs collected with the BABAR detector at the…
We have observed a signal for the decay D*+ -> D+ gamma at a significance of 4 standard deviations. From the measured branching ratio B(D*+ -> D+ gamma)/B(D*+ -> D+ pi0)=0.055 +- 0.014 +- 0.010 we find B(D*+ -> D+ gamma)= 0.017 +- 0.004 +-…
The first observation of the $\Xi_b^0 \to J/\psi \Xi^- \pi^+$ decay and the most precise measurement of the branching fraction of the $\Lambda_b^0 \to J/\psi \Xi^- K^+$ decay are reported, using proton-proton collision data from the LHCb…
We report the first observation of the decay \bar{B0} -> D_s^+ Lambda \bar{p} with a statistical significance of 6.6 sigma. We measure Br(\bar{B0} -> Ds+ Lambda \bar{p}) = (2.9 \pm 0.7\pm 0.5 \pm 0.4)* 10^{-5}, where the first error is…
We report on a new measurement of the branching ratio B(KL -> pi0 e+ e- gamma) using the KTeV detector. This analysis uses the full KTeV data set collected from 1997 to 2000. We reconstruct 139 events over a background of 14, which results…
Using the full data set of the NA48/2 experiment, the decay K+- -> pi+- e+ e- gamma is observed for the first time, selecting 120 candidates with 7.3 +- 1.7 estimated background events. With K+- -> pi+- pi0D as normalisation channel, the…
The cross section of the process e+ e- --> pi0 pi0 gamma has been measured in the c.m. energy range 600--970 MeV with the CMD-2 detector. The following branching ratios have been determined: B(rho --> pi0 pi0 gamma) =(5.2^{+1.5}_{-1.3} +-…
Based on a data sample corresponding to an integrated luminosity of 6.4~fb$^{-1}$ of $e^+e^-$ annihilation and collected with the BESIII detector at 13 center-of-mass energy points ranging between 4.600~GeV and 4.950~GeV, we report the…
We present the first model-independent measurement of the absolute branching fraction of the Lambda_c+ -> p K- pi+ decay using a data sample of 978 fb^-1 collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The…
We report the measurement of the charmed baryonic decay B0bar->Lambda_c+pbar with a branching fraction of (2.19^{+0.56}_{-0.49}+-0.32+-0.57)x10^{-5} and a statistical significance of 5.8 sigma. The errors are statistical, systematic, and…
We present branching fraction measurements for the radiative decays B+ -> rho+ gamma, B0 -> rho0 gamma, and B0 -> omega gamma. The analysis is based on a data sample of 465 million BBbar events collected with the BaBar detector at the…
Based on a sample of 500 million $e^+e^- \to c\bar c$ events recorded by the BaBar detector at c.m. energies of close to 10.6 GeV, we report on a study of the decay $D^0 \to \pi^- e^+ \nu_e$. We measure the ratio of branching fractions $R_D…
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…
The branching fraction of the rate decay $B^0 \rightarrow K^{*0}e^+e^-$ in the dilepton mass region from 30 to 1000 MeV$/c^2$ has been measured by the LHCb experiment, using $pp$ collision data, corresponding to an integrated luminosity of…
By analyzing $(10087 \pm 44)\times10^6$ $J/\psi$ events collected with the BESIII detector at the BEPCII, the decays $J/\psi\to \Xi^0\bar\Lambda K^0_S+c.c.$, $J/\psi\to \Xi^0\bar\Sigma^0 K^0_S+c.c.$, and $J/\psi\to \Xi^0\bar\Sigma^-…
The Cabibbo-allowed weak radiative decay $\Lambda_{c}^+\to \Sigma^+\gamma$ has been searched for in a sample of $\Lambda_{c}^+\bar{\Lambda}_{c}^-$ pairs produced in $e^+e^-$ annihilations, corresponding to an integrated luminosity of $4.5…
We present preliminary results of a search for the decays B+ -> rho+ gamma, B0 -> rho0 gamma, and B0 -> omega gamma. The analysis is based on data containing 347 million BB events recorded with the BaBar detector at the PEP-II B factory. We…