No Arabic abstract
We present a measurement of the relative branching fraction, R_{f_{0}/phi}, of B_{s}^{0} to J/psi f_{0}(980), with f_{0}(980) to pi^+ pi^-, to the process B_{s}^{0} to J/psi phi, with phi to K^+K^-. The J/psi f_{0}(980) final state corresponds to a CP-odd eigenstate of B_{s}^{0} that could be of interest in future studies of CP violation. Using approximately 8fb^-1 of data recorded with the D0 detector at the Fermilab Tevatron Collider, we find R_{f_{0}/phi} = 0.275 +- 0.041(stat) +- 0.061(syst).
A measurement of the relative branching fraction of $B_{s}^{0} rightarrow J/ps i f_{0}(980), f_{0}(980) rightarrow pi^{+}pi^{-}$ to $B_{s}^{0} rightarrow J/psi phi, p hi rightarrow K^{+}K^{-}$ is presented. The decay mode $B_{s}^{0} rightarrow J/psi f_{0}(980)$ is an interesting mode since it is a CP-odd eigenstate which could be used in CP-violating studies. Using approximat ely 8 $rm{fb}^{-1}$ of data recorded with the D0 detector at the Fermilab Tevatron Collider, a relative branching fraction of 0.210 $pm$ 0.032thinspace(stat) $pm$ 0.036thi nspace(syst) is found.
Using a sample of 1.31 billion $J/psi$ events collected with the BESIII detector at the BEPCII collider, the decays $J/psi to phi pi^{+}pi^{-}pi^{0}$ and $J/psi to phi pi^{0}pi^{0}pi^{0}$ are investigated. The isospin violating decay $J/psi to phi pi^{0} f_{0}(980)$ with $f_{0}(980) to pipi$, is observed for the first time. The width of the $f_{0}(980)$ obtained from the dipion mass spectrum is found to be much smaller than the world average value. In the $pi^{0} f_{0}(980)$ mass spectrum, there is evidence of $f_1(1285)$ production. By studying the decay $J/psi to phieta$, the branching fractions of $eta to pi^{+}pi^{-}pi^{0}$ and $eta to pi^{0}pi^{0}pi^{0}$, as well as their ratio, are also measured.
A search for the rare decay of a $B^{0}$ or $B^{0}_{s}$ meson into the final state $J/psigamma$ is performed, using data collected by the LHCb experiment in $pp$ collisions at $sqrt{s}=7$ and $8$ TeV, corresponding to an integrated luminosity of 3 fb$^{-1}$. The observed number of signal candidates is consistent with a background-only hypothesis. Branching fraction values larger than $1.7times 10^{-6}$ for the $B^{0}to J/psigamma$ decay mode are excluded at 90% confidence level. For the $B^{0}_{s}to J/psigamma$ decay mode, branching fraction values larger than $7.4times 10^{-6}$ are excluded at 90% confidence level, this is the first branching fraction limit for this decay.
The ratio of branching fractions $R_{K/pi} equiv mathcal{B}(B_{c}^{+} to J/psi K^{+})/mathcal{B}(B_{c}^{+} to J/psipi^{+})$ is measured with $pp$ collision data collected by the LHCb experiment at centre-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of 3${mbox{fb}^{-1}}$. It is found to be $ R_{K/pi} = 0.079pm0.007pm0.003$, where the first uncertainty is statistical and the second is systematic. This measurement is consistent with the previous LHCb result, while the uncertainties are significantly reduced.
Using a data set corresponding to an integrated luminosity of $3 fb^{-1}$, collected by the LHCb experiment in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV, the effective lifetime in the $B^0_s rightarrow J/psi eta$ decay mode, $tau_{textrm{eff}}$, is measured to be $tau_{textrm{eff}} = 1.479 pm 0.034~textrm{(stat)} pm 0.011 ~textrm{(syst)}$ ps. Assuming $CP$ conservation, $tau_{textrm{eff}}$ corresponds to the lifetime of the light $B_s^0$ mass eigenstate. This is the first measurement of the effective lifetime in this decay mode.