No Arabic abstract
Using $(106.41pm 0.86) times 10^{6}$ $psi(3686)$ events collected with the BESIII detector at BEPCII, we study for the first time the decay $chi_{cJ}toetaK^+K^-$, where $etatogammarho^{0}$ and $etatoetapi^+pi^-$. A partial wave analysis in the covariant tensor amplitude formalism is performed for the decay $chi_{c1}toetaK^+K^-$. Intermediate processes $chi_{c1}toeta f_0(980)$, $chi_{c1}toeta f_0(1710)$, $chi_{c1}toeta f_2(1525)$ and $chi_{c1}to K^*_0(1430)^{pm}K^{mp}$ ($K^*_0(1430)^{pm}toeta K^{pm}$) are observed with statistical significances larger than 5$sigma$, and their branching fractions are measured.
Using a data sample of 106 million $psi(3686)$ events collected with the BESIII detector operated at the BEPCII storage ring, we study for the first time the decay $chi_{cJ}tophi K^{0}_S K^{pm}pi^{mp}$ and $chi_{cJ}tophi K^{+} K^{-}pi^{0}$ in the E1 radiative transition $psi(3686)togammachi_{cJ}$. The decays are dominated by the three-body decay $chi_{cJ}to phi K^*(892)bar{K}$. We measure branching fractions for this reaction via the neutral and charged $K^*(892)$ and find them consistent with each other within the expectation of isospin symmetry. In the $Kbar{K}pi$ invariant mass distribution a structure near the $K^*(892)bar{K}$ mass threshold is observed, and the corresponding mass and width are measured to be $1412pm4(mathrm{stat.})pm8(mathrm{sys.}) mathrm{MeV}/c^2$ and $Gamma$ = $84pm12(mathrm{stat.})pm40(mathrm{sys.}) mathrm{MeV}$, respectively. The observed state favors an assignment to the $h_1(1380)$, considering its possible $J^{PC}$ and comparing its mass, width and decay mode to those reported in the Particle Data Group.
Using a data sample of $1.06 times 10^{8}$ $psip$ events collected with the BESIII detector in 2009, the branching fractions of $chi_{cJ}to pbar{n}pi^{-}$ and $chi_{cJ}to pbar{n}pi^{-}pi^{0}$ ($J$=0,1,2) are measured{Throughout the text, inclusion of charge conjugate modes is implied if not stated otherwise.}. The results for $chi_{c0}to pbar{n}pi^{-}$ and $chi_{c2}to pbar{n}pi^{-}$ are consistent with, but much more precise than those of previous measurements. The decays of $chi_{c1}to pbar{n}pi^{-}$ and $chi_{cJ}to pbar{n}pi^{-}pi^{0}$ are observed for the first time.
By analyzing $2.93 rm fb^{-1}$ of data taken at a center-of-mass energy of 3.773~GeV with the BESIII detector, we measure the branching fractions of the Cabibbo-favored hadronic decays $D^0to K^-pi^+eta^prime$, $D^0to K^0_Spi^0eta^prime$ and $D^+to K^0_Spi^+eta^prime$, which are determined to be $(6.43 pm 0.15_{rm stat.} pm 0.31_{rm syst.})times 10^{-3}$, $(2.52 pm 0.22_{rm stat.} pm 0.15_{rm syst.})times 10^{-3}$ and $(1.90 pm 0.17_{rm stat.} pm 0.13_{rm syst.})times 10^{-3}$, respectively. The precision of the branching fraction of $D^0to K^-pi^+eta^prime$ is significantly improved, and the processes $D^0to K^0_Spi^0eta^prime$ and $D^+to K^0_Spi^+eta^prime$ are observed for the first time.
Hadronic transitions of $chi_{cJ}to eta_{c}pi^{+}pi^{-}$ (J=0, 1, 2) are searched for using a sample of $1.06times 10^{8}$ $psi(3686)$ events collected with the BESIII detector at the BEPCII storage ring. The $etac$ is reconstructed with $K_{S}^{0}K^{+}pi^{-}+c.c.$ and $K^{+}K^{-}pi^{0}$ final states. No signals are observed in any of the three $chi_{cJ}$ states in either $etac$ decay mode. At the 90% confidence level, the upper limits are determined to be $BR(chi_{c0}to eta_{c}pi^{+}pi^{-})<0.07%$, $BR(chi_{c1}to eta_{c}pi^{+}pi^{-})<0.32%$, and $BR(chi_{c2}to eta_{c}pi^{+}pi^{-})<0.54%$. The upper limit of $BR(chi_{c1}to eta_{c}pi^{+}pi^{-}$ is lower than the existing theoretical prediction by almost an order of magnitude. The branching fractions of $chi_{cJ}to K_{S}^{0}K^{+}pi^{-}pi^{+}pi^{-}+c.c.$, $K^{+}K^{-}pi^{+}pi^{-}pi^{0}$, $omega K^{+}K^{-}$ and $phipi^{+}pi^{-}pi^{0}$ (J=0, 1, 2) are measured for the first time.
By analyzing $4.48times10^8$ $psi(3686)$ events collected with the BESIII detector, we observe the decays $chi_{cJ} to n K^0_SbarLambda + c.c.$ ($J=0$, 1, 2) for the first time, via the radiative transition $psi(3686) to gamma chi_{cJ}$. The branching fractions are determined to be $(6.67 pm 0.26_{rm stat} pm 0.41_{rm syst})times10^{-4}$, $(1.71 pm 0.12_{rm stat} pm 0.12_{rm syst})times10^{-4}$, and $(3.66 pm 0.17_{rm stat} pm 0.23_{rm syst})times10^{-4}$ for $J=0$, 1, and 2, respectively.