Measurements of $\psip$ decays into $\gamma K\bar{K}\pi$ and $\gamma\eta\pipi$

Using $\gamma \gamma J/\psi, J/\psi \ra e^+ e^-$ and $\mu^+ \mu^-$ events from a sample of $14.0\times 10^6$ $\psip$ decays collected with the BESII detector, the branching fractions for $\psip\ra \pi^0\J$, $\eta\J$, and $\psi(2S)\ar\gamma\chi_{c1},\gamma\chi_{c2}\ar\gamma\gamma\jpsi$ are measured to be $B(\psip\ra \pi^0\J) = (1.43\pm0.14\pm0.13)\times 10^{-3}$, $B(\psip\ra \eta\J) = (2.98\pm0.09\pm0.23)%$, $B(\psi(2S)\ar\gamma\chi_{c1}\ar\gamma\gamma\jpsi) = (2.81\pm0.05\pm ...

We search for the hadronic decay $\eta_c(2S)\to 2(\pi^+\pi^-)$ in the $\psi(3686)\to\gamma\eta_c(2S)$ radiative decay using $(27.12\pm 0.14)\times 10^8$ $\psi(3686)$ events collected by the BESIII detector at the BEPCII collider. No significant signal is found, and the upper limit of $\mathcal{B}[\psi(3686)\to\gamma\eta_c(2S)]\mathcal{B}[\eta_c(2S)\to 2(\pi^+\pi^-)]$ is determined to be $0.78\times 10^{-6}$ at the 90\% confidence level. Using $\psi(3686)\to\gamma\chi_{cJ}$ tr...

Using a sample of $1.06\times10^{8}~\psi(3686)$ events collected with the BESIII detector at BEPCII, the decays $\eta_{c}(2S)\to p\bar{p}$ and $h_{c}\to p\bar{p}$ are searched for, where $\eta_c(2S)$ and $h_c$ are reconstructed in the decay chains $\psi(3686)\to\gamma\eta_{c}(2S)$, $\eta_{c}(2S)\to p\bar{p}$ and $\psi(3686)\to\pi^{0}h_{c}$, $h_{c}\to p\bar{p}$, respectively. No significant signals are observed. The upper limits of the product branching fractions are determine...

Radiative charmonium decays from the BESII sample of 14$\times10^{6}$ $\psi(2S)$-events into two different final states, $\gamma K^+K^-$ and $\gamma\pi^+\pi^-$, are analyzed. Product branching fractions for $\psi(2S)\to\gamma X\to \gamma\pi^+\pi^-$, $\gamma K^+K^-$ are given, where $X=f_2(1270)$, $f_0(1500)$, and $f_0(1710)$ in $\pi^+\pi^-$ and $f_2(1270)$, $f_2'(1525)$, and $f_0(1700)$ in $K^+K^-$. An angular analysis gives the ratios of the helicity projections for the $f_2...

Using a sample of $1.06\times10^8\ \psip$ events produced in $e^+e^-$ collisions at $\sqrt{s}$ = 3.686 GeV and collected with the BESIII detector at the BEPCII collider, we present studies of the decays $\klx+c.c.$ and $\gklx+c.c.$. We observe two hyperons, $\Xi(1690)^-$ and $\Xi(1820)^-$, in the $K^-\Lambda$ invariant mass distribution in the decay $\klx+c.c.$ with significances of $4.9 \sigma$ and $6.2 \sigma$, respectively. The branching fractions of $\klx+c.c.$, $\ksx+c.c...

Using a data sample of $2.25\times10^{8}$ $J/\psi$ events collected with the BESIII detector, we present the first observation of the decays of $\eta_{c}$ mesons to $\Sigma^{+}\bar{\Sigma}^{-}$ and $\Xi^{-}\bar{\Xi}^{+}$. The branching fractions are measured to be $(2.11\pm0.28_{\rm stat.}\pm0.18_{\rm syst.}\pm0.50_{\rm PDG})\times10^{-3}$ and $(0.89\pm0.16_{\rm stat.}\pm0.08_{\rm syst.}\pm0.21_{\rm PDG})\times10^{-3}$ for $\eta_{c} \to \Sigma^{+}\bar{\Sigma}^{-}$ and $\Xi^{-...

Using 14 million $\psi(2S)$ events collected with the BESII detector, branching fractions of $\psip\rar\kstarkpm$ and $\kstarknn$ are determined to be: $\calB(\psip\rar\kstarkpm)=(2.9^{+1.3}_{-1.7}\pm0.4)\times 10^{-5}$ and $\calB(\psip\rar\kstarknn)=(13.3^{+2.4}_{-2.7}\pm1.9)\times 10^{-5}$. The results confirm the violation of the "12%" rule for these two decay channels with higher precision. A large isospin violation between the charged and neutral modes is observed.

$\chi_{c0}$, $\chi_{c1}$, and $\chi_{c2}$ decays to $\pi^+\pi^-K^0_SK^0_S$ and $K^+K^-K^0_SK^0_S$, as well as $\psi(2S)$ decay to $\pi^+\pi^-K^0_SK^0_S$ are presented. The branching fractions of these decay channels are determined using $14\times 10^6$ $\psi(2S)$ events collected at BESII/BEPC. The branching fractions of $\chi_{c0},\chi_{c2}\to K^0_SK^0_S$ are measured with improved statistical precision.

Based on 106 million $\psi(3686)$ events collected with the BESIII detector at the BEPCII, the decay $\psi(3686) \rightarrow \omega K \bar{K} \pi$ is studied. Enhancements around 1.44 GeV/$c^{2}$ and the $f_{1}(1285)$ are observed in the mass spectrum of $K \bar{K}\pi$, and the corresponding branching fractions are measured, as well as the branching fractions of $\psi(3686) \rightarrow \omega K^{*+}K^{-}+c.c.$ and $\psi(3686) \rightarrow \omega \bar{K}^{*0}K^{0}+c.c.$, all fo...

The first observation of the decays $J\!/\!\psi \rightarrow \bar{p} \Sigma^{+} K_{S}^{0}$ and $J\!/\!\psi \rightarrow p \bar{\Sigma}^{-} K_{S}^{0}$ is reported using $(10087\pm44)\times10^{6}$ $J\!/\!\psi$ events recorded by the BESIII detector at the BEPCII storage ring. The branching fractions of each channel are determined to be $\mathcal{B}(J\!/\!\psi \rightarrow \bar{p} \Sigma^{+} K_{S}^{0})=(1.361 \pm 0.006 \pm 0.025) \times 10^{-4}$ and $\mathcal{B}(J\!/\!\psi \rightar...