Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userMeasurement of the $Omega_c^0$ Lifetime
100
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The FOCUS experiment(FNAL-E831) has used two channels, $Omega^- pi^+$ and $Xi^-K^- pi^+ pi^+$,to measure the lifetime of the $Omega_c^0$ charmed baryon. From a sample of $64 pm 14$ signal events at a mass of 2.698 GeV/$c^2$, we measure an $Omega_c^0$ lifetime of $72 pm 11$ (stat.) $pm 11$ (sys.) fs, substantially improving upon the current world average.
rate research
Read More
We report a measurement of the lifetime of the $Omega_c^0$ baryon using proton-proton collision data at center-of-mass energies of 7 and 8~TeV, corresponding to an integrated luminosity of 3.0 fb$^{-1}$ collected by the LHCb experiment. The sample consists of about 1000 $Omega_b^-toOmega_c^0mu^-bar{ u}_{mu} X$ signal decays, where the $Omega_c^0$ baryon is detected in the $pK^-K^-pi^+$ final state and $X$ represents possible additional undetected particles in the decay. The $Omega_c^0$ lifetime is measured to be $tau_{Omega_c^0} = 268pm24pm10pm2$ fs, where the uncertainties are statistical, systematic, and from the uncertainty in the $D^+$ lifetime, respectively. This value is nearly four times larger than, and inconsistent with, the current world-average value.
We report results from a study of the charmed double strange baryons Omega_c^0 and Omega_c^{*0} at Belle. The Omega_c^0 is reconstructed using the Omega_c^0 --> Omega^- pi^+ decay mode, and its mass is measured to be (2693.6 pm 0.3 {+1.8 atop -1.5}) MeV/c^2. The Omega_c^{*0} baryon is reconstructed in the Omega_c^0 gamma mode. The mass difference M_{Omega_c^{*0}} - M_{Omega_c^0} is measured to be (70.7 pm 0.9 {+0.1 atop -0.9}) MeV/c^2. The analysis is performed using 673 fb^{-1} of data on and near the Upsilon(4S) collected with the Belle detector at the KEKB asymmetric-energy e^+e^- collider.
Using a data sample of 980 ${rm fb}^{-1}$ of $e^+e^-$ annihilation data taken with the Belle detector operating at the KEKB asymmetric-energy $e^+e^-$ collider, we report the results of a study of the decays of the $Omega_c^0$ charmed baryon into hadronic final states. We report the most precise measurements to date of the relative branching fractions of the $Omega_c^0$ into $Omega^-pi^+pi^0$, $Omega^-pi^+pi^-pi^+$, $Xi^-K^-pi^+pi^+$, and $Xi^0K^-pi^+$, as well as the first measurements of the branching fractions of the $Omega_c^0$ into $Xi^-bar{K}^0pi^+$, $Xi^0bar{K}^0$, and $Lambda bar{K}^0bar{K}^0$, all with respect to the $Omega^-pi^+$ decay. In addition, we investigate the resonant substructure of these modes. Finally, we present a limit on the branching fraction for the decay $Omega_c^0toSigma^+K^-K^-pi^+$.
This paper reports the first measurement of the effective B_s^0 -> J/{psi} K_S^0 lifetime and an updated measurement of its time-integrated branching fraction. Both measurements are performed with a data sample, corresponding to an integrated luminosity of 1.0 fb^{-1} of pp collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: tau_J/{psi}K_S^0 = 1.75 +/- 0.12 (stat) +/- 0.07 (syst) and BR(B_s^0 -> J/{psi} K_S^0) = (1.97 +/- 0.23) X 10^{-5}. For the latter measurement, the uncertainty includes both statistical and systematic sources.
A precise determination of the effective $B_s^0 rightarrow K^+ K^-$ lifetime can be used to constrain contributions from physics beyond the Standard Model in the $B_s^0$ meson system. Conventional approaches select $B$ meson decay products that are significantly displaced from the $B$ meson production vertex. As a consequence, $B$ mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb$^{-1}$ of data recorded by the LHCb experiment, the effective $B_s^0 rightarrow K^+ K^-$ lifetime is measured as $1.455 pm 0.046 ; mathrm{(stat.)} pm 0.006 ; mathrm{(syst.)} , mathrm{ps}.$
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
