Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSearch for B decays to final states with the eta_c meson
257
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We report a search for $B$ decays to selected final states with the $eta_c$ meson: $B^{pm}to K^{pm}eta_cpi^+pi^-$, $B^{pm}to K^{pm}eta_comega$, $B^{pm}to K^{pm}eta_ceta$ and $B^{pm}to K^{pm}eta_cpi^0$. The analysis is based on $772times 10^6$ $Bbar{B}$ pairs collected at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We set 90% confidence level upper limits on the branching fractions of the studied $B$ decay modes, independent of intermediate resonances, in the range $(0.6-5.3)times 10^{-4}$. We also search for molecular-state candidates in the $D^0bar{D}^{*0}-bar{D}^0D^{*0}$, $D^0bar{D}^0+bar{D}^0D^0$ and $D^{*0}bar{D}^{*0}+bar{D}^{*0}D^{*0}$ combinations, neutral partners of the $Z(3900)^{pm}$ and $Z(4020)^{pm}$, and a poorly understood state $X(3915)$ as possible intermediate states in the decay chain, and set 90% confidence level upper limits on the product of branching fractions to the mentioned intermediate states and decay branching fractions of these states in the range $(0.6-6.9)times 10^{-5}$.
rate research
Read More
We report a search for $B^{0}$ decays into invisible final states using a data sample of $657 times 10^{6}$ $Bbar{B}$ pairs collected at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^{+}e^{-}$ collider. The signal is identified by fully reconstructing a hadronic decay of the accompanying $B$ meson and requiring no other particles in the event. No significant signal is observed, and we obtain an upper limit of $1.3 times 10^{-4}$ at the 90% confidence level for the branching fraction of invisible $B^{0}$ decay.
We report searches for $B^0torm{invisible}$ and $B^0torm{invisible}+gamma$ decays, where the energy of the photon is required to be larger than 0.5 GeV. These results are obtained from a $711,{rm fb}^{-1}$ data sample that contains $772 times 10^6 Bbar{B}$ pairs and was collected near the $Upsilon,(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. We observe no significant signal for either decay and set upper limits on their branching fractions at $90%$ confidence level of $mathcal{B},(B^0torm{invisible}) < 7.8times10^{-5}$ and $mathcal{B},(B^0torm{invisible}+gamma) < 1.6times10^{-5}$.
We report the result from the first search for $D^0$ decays to invisible final states. The analysis is performed on a data sample of 924 $rm{fb}^{-1}$ collected at and near the $Upsilon(4S)$ and $Upsilon(5S)$ resonances with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. The absolute branching fraction is determined using an inclusive $D^0$ sample, obtained by fully reconstructing the rest of the particle system including the other charmed particle. No significant signal yield is observed and an upper limit of $9.4times 10^{-5}$ is set on the branching fraction of $D^0$ to invisible final states at 90% confidence level.
A Dalitz plot analysis of $B^0 to eta_c(1S) K^+pi^-$ decays is performed using data samples of $pp$ collisions collected with the LHCb detector at centre-of-mass energies of $sqrt{s}=7,~8$ and $13$ TeV, corresponding to a total integrated luminosity of $4.7~text{fb}^{-1}$. A satisfactory description of the data is obtained when including a contribution representing an exotic $eta_c(1S) pi^-$ resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are $4096 pm 20~^{+18}_{-22}$ MeV and $152 pm 58~^{+60}_{-35}$ MeV, respectively. The spin-parity assignments $J^P=0^+$ and $J^{P}=1^-$ are both consistent with the data. In addition, the first measurement of the $B^0 to eta_c(1S) K^+pi^-$ branching fraction is performed and gives $displaystyle mathcal{B}(B^0 to eta_c(1S) K^+pi^-) = (5.73 pm 0.24 pm 0.13 pm 0.66) times 10^{-4}$, where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions.
Using a sample of 2.59 times 10^7 psi(2S) decays collected by the CLEO--c detector, we present results of a study of chi_{c0} and chi_{c2} decays into two-meson final states. We present the worlds most precise measurements of the chi_{cJ,(J=0,2)} -> pi^+pi^-, pi^0 pi^0, K^+K^-, K^0_S K^0_S, eta eta and eta^{prime} eta^{prime} branching fractions, and a search for chi_c decays into eta eta^{prime}. These results shed light on the mechanism of charmonium decays into pseudoscalar mesons.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
