No Arabic abstract
The possibility of the $0^+$ $etaeta$ resonance $f_0(2100)$ as a candidate of the $Q^2bar{Q}^2$ state $C^{ss}(36)$ is explored. The $etaeta$ channel of $f_0(2100)$ is the dominant decay mode, $etaeta$ channel has less decay rate, the decay rate of the $etaeta$ channel is very small. The $pipi,;Kbar{K},;4pi$ modes are at next leading order in $N_C$ expansion. Other possible decay modes are discussed.
The possible existence of a ($ sbar s$) S = 0 meson at M $approx$ 762 MeV is discussed through a critical analysis of the existing data. Different experimental results are considered and show the possibility that the presence of such meson is not excluded by the data, but may be hidden by more excited mesons at nearby masses.
We investigate the processes $e^+e^-$$to$$gamma J/psiphi$, $gamma J/psiomega$ and $pi^0 J/psieta$ to search for the charmnium-like states with hidden $sbar{s}$, such as $Y(4140)$, $Y(4274)$, $X(4350)$ and $X(3915)$. These processes will receive contributions from the charmed-strange meson rescatterings. When the center-of-mass energies of the $e^+e^-$ scatterings are taken around the $D_{s0}(2317)D_s^{*}$, $D_{s1}(2460)D_s$ or $D_{s1}(2460)D_s^{*}$ threshold, the anomalous triangle singularities can be present in the rescattering amplitudes, which implies a non-resonance explanation about the resonance-like structures. The positions of the anomalous triangle singularities are sensitive to the kinematics, which offers us a criterion to distinguish the kinematic singularities from genuine particles.
We report the first search for the penguin-dominated process $B_{s}^{0} rightarrow eta^{prime} X_{sbar{s}}$ using a semi-inclusive method. A 121.4 $mathrm{fb}^{-1}$ integrated luminosity $Upsilon(5S)$ data set collected by the Belle experiment, at the KEKB asymmetric-energy $e^+e^-$ collider, is used. We observe no statistically significant signal and including all uncertainties, we set a 90% confidence level upper limit on the partial branching fraction at 1.4 $times$ 10$^{-3}$ for $M(X_{sbar{s}})$ $leq$ 2.4 GeV/$c^{2}$.
The possibility of X(1835) as a 0^{-+} glueball is investigated.
A search for charmless three-body decays of $B^0$ and $B_{s}^0$ mesons with a $K_{rm S}^0$ meson in the final state is performed using the $pp$ collision data, corresponding to an integrated luminosity of $1.0,mbox{fb}^{-1}$, collected at a centre-of-mass energy of $7mathrm{,Tekern -0.1em V}$ recorded by the LHCb experiment. Branching fractions of the $B_{(s)}^0 to K_{rm S}^0 h^{+} h^{prime -}$ decay modes ($h^{(prime)} = pi, K$), relative to the well measured $B^0 to K_{rm S}^0 pi^{+} pi^{-}$ decay, are obtained. First observation of the decay modes $B_s^0 to K_{rm S}^0 K^{pm} pi^{mp}$ and $B_s^0 to K_{rm S}^0 pi^{+} pi^{-}$ and confirmation of the decay $B^0 to K_{rm S}^0 K^{pm} pi^{mp}$ are reported. The following relative branching fraction measurements or limits are obtained begin{eqnarray*} onumber frac{{cal B}(B^0 to K_{rm S}^0 K^{pm} pi^{mp})}{{cal B}(B^0 to K_{rm S}^0 pi^{+} pi^{-})} &=& 0.128 pm 0.017 , ({rm stat.}) pm 0.009 , ({rm syst.}) ,, onumber frac{{cal B}(B^0 to K_{rm S}^0 K^{+} K^{-} )}{{cal B}(B^0 to K_{rm S}^0 pi^{+} pi^{-})} &=& 0.385 pm 0.031 , ({rm stat.}) pm 0.023 , ({rm syst.}) ,, onumber frac{{cal B}(B_s^0 to K_{rm S}^0 pi^{+} pi^{-} )}{{cal B}(B^0 to K_{rm S}^0 pi^{+} pi^{-})} &=& 0.29phantom{0} pm 0.06phantom{0} , ({rm stat.}) pm 0.03phantom{0} , ({rm syst.}) pm 0.02 , (f_s/f_d) ,, onumber frac{{cal B}(B_s^0 to K_{rm S}^0 K^{pm} pi^{mp})}{{cal B}(B^0 to K_{rm S}^0 pi^{+} pi^{-})} &=& 1.48phantom{0} pm 0.12phantom{0} , ({rm stat.}) pm 0.08phantom{0} , ({rm syst.}) pm 0.12 , (f_s/f_d) ,, onumber frac{{cal B}(B_s^0 to K_{rm S}^0 K^{+} K^{-} )}{{cal B}(B^0 to K_{rm S}^0 pi^{+} pi^{-})} &in& [0.004;0.068] ; {rm at ;; 90% ; CL} ,. end{eqnarray*}