相关论文: Measurement of the Lambda_b lifetime in the exclus…
Recent results on the $B$ CP-violation parameter $\sin2\phi_1$, the $B^0_d$-$\overline{B}^0_d$ mixing parameter $\Delta m_d$ and $B$-meson lifetimes are reported. The results are based on 10.5 $fb^{-1}$ of data collected with the Belle…
A high statistics measurement of the Lambdac+ lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis technique with particular attention to the determination of the systematic…
We present the first observation of the lambda_b->lambda_c pi-pi+pi- decay using data from an integrated luminosity of approximately 2.4 fb-1 of ppbar collisions at ECM=1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron.…
Recent results of a high-statistics study of tau lepton properties and decays at B factories are reviewed. We discuss measurements of tau lifetime, branching fractions, and spectral functions for several hadronic tau decay modes with…
The decay $\Lambda_b^0 \to \Lambda_c^+ p \overline{p} \pi^-$ is observed using $pp$ collision data collected with the LHCb detector at centre-of-mass energies of $\sqrt{s}=$ 7 and 8 TeV, corresponding to an integrated luminosity of 3…
We measure the masses of $b$ hadrons in exclusively reconstructed final states containing a $J/\psi\to\mu^-\mu^+$ decay using $\rm 220 pb^{-1}$ of data collected by the CDF II experiment. We find: m(B^+) = 5279.10 \pm 0.41_{(stat.)} \pm…
Measurements of $B_c^+$ production and mass are performed with the decay mode $B_c^+ \to J/\psi \pi^+$ using 0.37 fb$^{-1}$ of data collected in $pp$ collisions at $\sqrt{s}=7$ TeV by the LHCb experiment. The ratio of the production…
We measure the rate of D0-D0bar mixing with the observable yCP=(tauKpi/tauKK)-1, where tauKK and tauKpi are respectively the mean lifetimes of CP-even D0->K+K- and CP-mixed D0->K-pi+ decays, using a data sample of 384/fb collected by the…
A new measurement of the mean lifetime of the tau lepton is presented. Three different analysis methods are applied to a sample of 90000 tau pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement…
We report the observation of B- -> J/psi Lambda pbar and searches for B- -> J/psi Sigma0 pbar and B0 -> J/psi p pbar decays, using a sample of 275 million BBbar pairs collected with the Belle detector at the Upsilon(4S) resonance. We…
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 measure the branching ratio of the purely leptonic decay of the D+ meson with unprecedented precision as B(D+ -> mu+ nu) = (3.82 +/- 0.32 +/- 0.09)x10^(-4), using 818/pb of data taken on the psi(3770) resonance with the CLEO-c detector…
Using data recorded by the CLEO III detector at CESR, we report on the first measurements of the branching fractions for decays of the Lambda_c^+ charmed baryon into (Lambda pi+ pi+ pi- pi0) and (Lambda omega pi+). All rates are measured…
The \Lambda_b(udb) baryon is observed in the decay \Lambda_b --> J/\psi \Lambda using 6.1 fb^{-1} of p\bar{p} collisions collected with the D0 detector at \sqrt{s}=1.96 TeV. The production fraction multiplied by the branching fraction for…
Bottom baryons decaying to a J/\psi\ meson and a hyperon are reconstructed using 1.0 fb^{-1} of data collected in 2011 with the LHCb detector. Significant \Lambda_b^0 \rightarrow J/\psi \Lambda, \Xi_b^-\rightarrow J/\psi \Xi^- and…
We examine in detail the semi-leptonic decay $\Lambda_b \to \Lambda_c \tau{\bar \nu}_{\tau}$, which may confirm previous hints, from the analogous $B$ decay, of a new physics beyond the standard model. First of all, starting from rather…
Using the CLEO II detector at CESR, we observe 500 $\Lambda l^+$ pairs consistent with the semileptonic decay $\Lambda_c \to \Lambda l^+ \nu_{l}$. We measure $\sigma (e^+ e^- \to \Lambda_c X) \dot {cal B}(\Lambda_c^+ \to \Lambda l \nu_{l})…
We estimate the decay width difference $\Delta Gamma_d / \Gamma_d$ in the $B_d$ system including $1/m_b$ contributions and next-to-leading order QCD corrections, and find it to be around 0.3%. We explicitly show that the time measurements…
The CDF collaboration presents an updated measurement of the CP-violating parameter beta_s and of the decay width difference Delta Gamma_s using approximately 6500 Bs to J/Psi Phi decays collected by the dimuon trigger and reconstructed in…
Time-dependent B0-antiB0 flavor oscillations and B0 and B+ lifetimes are studied in a sample of fully reconstructed B mesons collected with the BaBar detector, running at the PEP-II asymmetric e+e- B Factory with center-of-mass energies…