Publications (56)87.16 Total impact

Article: Evidence for $e^+e^\to\gamma\chi_{c1, 2}$ at centerofmass energies from 4.009 to 4.360 GeV
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ABSTRACT: Using data samples collected at centerofmass energies of $\sqrt{s}$ = 4.009, 4.230, 4.260, and 4.360 GeV with the BESIII detector operating at the BEPCII collider, we perform a search for the process $e^+e^\to\gamma\chi_{cJ}$ $(J = 0, 1, 2)$ and find evidence for $e^+e^\to\gamma\chi_{c1}$ and $e^+e^\to\gamma\chi_{c2}$ with statistical significances of 3.0$\sigma$ and 3.4$\sigma$, respectively. The Born cross sections $\sigma^{B}(e^+e^\to\gamma\chi_{cJ})$, as well as their upper limits at the 90% confidence level are determined at each centerofmass energy.11/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using a sample of $2.25\times 10^8$ $J/\psi$ events collected with the BESIII detector at the BEPCII collider, we search for the $J/\psi$ semileptonic weak decay $J/\psi \to D^{}_{s} e^{+}\nu_{e}+c.c.$ with a much higher sensitivity than previous searches. We also perform the first search for $J/\psi \to D^{*}_{s} e^{+}\nu_{e}+c.c.$ No significant excess of a signal above background is observed in either channel. At the $90\%$ confidence level, the upper limits are determined to be $\mathcal{B}(J/\psi \to D^{}_{s}e^{+}\nu_{e}+c.c.)<1.3\times10^{6}$ and $\mathcal{B}(J/\psi \to {D^{*}_{s}}^{}e^{+}\nu_{e}+c.c.)<1.8\times10^{6}$, respectively. Both are consistent with Standard Model predictions.10/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Based on data samples collected with the BESIII detector at the BEPCII collider at 9 centerofmass energies from 4.21 to 4.42 GeV, we search for the production of $e^+e^\to \omega\chi_{cJ}$ ($J$=0, 1, 2). The process $e^+e^\to \omega\chi_{c0}$ is observed for the first time, and the Born cross sections at $\sqrt{s}$=4.23 and 4.26 GeV are measured to be $(55.4\pm 6.0\pm 5.9)$ and $(23.7\pm 5.3\pm 3.5)$ pb, respectively, where the first uncertainties are statistical and the second are systematic. The $\omega\chi_{c0}$ signals at the other 7 energies and $e^+e^\to \omega\chi_{c1}$ and $\omega\chi_{c2}$ signals are not significant, and the upper limits on the cross sections are determined. By examining the $\omega\chi_{c0}$ cross section as a function of centerofmass energy, we find that it is inconsistent with the line shape of the $Y(4260)$ observed in $e^+ e^\to\pi^+\pi^J/\psi$.10/2014; 
Article: Observation of $e^+e^\to \pi^0\pi^0 h_c$ and a neutral charmoniumlike structure $Z_c(4020)^0$
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ABSTRACT: Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at centerofmass energies of $\sqrt{s}$=4.23, 4.26, and 4.36 GeV, we observe $e^+e^\to \pi^0\pi^0 h_c$ for the first time. The Born cross sections are measured and found to be about half of those of $e^+e^ \to \pi^+\pi^h_c$ within less than 2$\sigma$. In the $\pi^0h_c$ mass spectrum, a structure at 4.02~GeV/$c^2$ that is most likely the neutral isospin partner of the $Z_c(4020)^{\pm}$ observed in the process of $e^+e^ \to \pi^+\pi^h_c$ is found. A fit to the $\pi^0 h_c$ invariant mass spectrum with the width of the $Z_c(4020)^0$ fixed to that of its charged isospin partner and possible interferences with non$Z_c(4020)^0$ amplitudes neglected, gives a mass of ($4023.9\pm 2.2 \pm 3.8$)~MeV/$c^2$ for the $Z_c(4020)^0$, where the first error is statistical and the second systematic.09/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using $1.06\times10^8$ $\psi(3686)$ events recorded in $e^{+}e^{}$ collisions at $\sqrt{s}=$ 3.686 GeV with the BESIII at the BEPCII collider, we present searches for Cparity violation in $J/\psi \to \gamma\gamma$ and $ \gamma \phi$ decays via $\psi(3686) \to J/\psi \pi^+\pi^$. No significant signals are observed in either channel. Upper limits on the branching fractions are set to be $\mathcal{B}(J/\psi \to \gamma\gamma) < 2.7 \times 10^{7}$ and $\mathcal{B}(J/\psi \to \gamma\phi) < 1.4 \times 10^{6}$ at the 90\% confidence level. The former is one order of magnitude more stringent than the previous upper limit, and the latter represents the first limit on this decay channel.09/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using $2.25\times10^{8}$ $J/\psi$ events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process $J/\psi\rightarrow p\bar{p}a_{0}(980)$, $a_{0}(980)\rightarrow \pi^{0}\eta$ with a significance of $6.5\sigma$ ($3.2\sigma$ including systematic uncertainties). The product branching fraction of $J/\psi\rightarrow p\bar{p}a_{0}(980)\rightarrow p\bar{p}\pi^{0}\eta$ is measured to be $(6.8\pm1.2\pm1.5)\times 10^{5}$, where the first error is statistical and the second is systematic. This measurement provides information on the $a_{0}$ production near threshold coupling to $p\bar{p}$ and improves the understanding of the dynamics of $J/\psi$ decays to four body processes.08/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using a sample of 1.3×10^{9} J/ψ events collected with the BESIII detector, we report the first observation of η^{'}→π^{+}π^{}π^{+}π^{} and η^{'}→π^{+}π^{}π^{0}π^{0}. The measured branching fractions are B(η^{'}→π^{+}π^{}π^{+}π^{})=[8.53±0.69(stat.)±0.64(syst.)]×10^{5} and B(η^{'}→π^{+}π^{}π^{0}π^{0})=[1.82±0.35(stat.)±0.18(syst.)]×10^{4}, which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vectormeson dominance.Physical Review Letters 06/2014; 112(25):251801. · 7.73 Impact Factor  [Show abstract] [Hide abstract]
ABSTRACT: The process $e^+e^\rightarrow p\overline{p}\pi^0$ has been studied by analyzing data collected at $\sqrt{s}=3.773$ GeV, at $\sqrt{s}=3.650$ GeV, and during a $\psi(3770)$ line shape scan with the BESIII detector at the BEPCII collider. The Born cross section of $p \overline{p} \pi^0$ in the vicinity of the $\psi(3770)$ is measured and the Born cross section of $\psi(3770)\rightarrow p \overline{p} \pi^0$ is extracted considering interference between resonant and continuum production amplitudes. Two solutions with the same probability and a significance of 1.5$\sigma$ are found, and the Born cross section of $\psi(3770)\rightarrow p \overline{p} \pi^0$ is determined to be less than 0.22 pb at 90% confidence level and $33.8\pm1.8\pm2.1$ pb, respectively. Using the estimated cross section and a constant decay amplitude approximation, the cross section $\sigma(p\overline{p} \rightarrow \psi(3770) \pi^0)$ is calculated for the kinematic situation of the planned $\overline{\text{P}}\text{ANDA}$ experiment. The maximum cross section corresponding to the two solutions is expected to be less than $0.79$ nb at 90% confidence level and $122\pm10$ nb at a center of mass energy of 5.26 GeV.06/2014;  [Show abstract] [Hide abstract]
ABSTRACT: By using a 2.92 fb$^{1}$ data sample taken at $\sqrt{s} = 3.773$ GeV with the BESIII detector operating at the BEPCII collider, we search for the radiative transitions $\psi(3770)\to\gamma\eta_c$ and $\gamma\eta_c(2S)$ through the hadronic decays $\eta_c(\eta_c(2S))\to K^0_SK^\pm\pi^\mp$. No significant excess of signal events above background is observed. We set upper limits at a 90% confidence level for the product branching fractions to be $\mathcal{B}(\psi(3770)\to\gamma\eta_c)\times \mathcal{B}(\eta_c\to K^0_SK^\pm\pi^\mp) < 1.6\times10^{5}$ and $\mathcal{B}(\psi(3770)\to\gamma\eta_c(2S))\times \mathcal{B}(\eta_c(2S)\to K^0_SK^\pm\pi^\mp) < 5.6\times10^{6}$. Combining our result with worldaverage values of $\mathcal{B}(\eta_c(\eta_c(2S))\to K^0_SK^\pm\pi^\mp)$, we find the branching fractions $\mathcal{B}(\psi(3770)\to\gamma\eta_c) < 6.8\times10^{4}$ and $\mathcal{B}(\psi(3770)\to\gamma\eta_c(2S)) < 2.0\times10^{3}$ at a 90% confidence level.05/2014;  [Show abstract] [Hide abstract]
ABSTRACT: With $1.06\times 10^8$ $\psi(3686)$ events collected with the BESIII detector, the branching fraction of $\psi(3686) \to \omega K^+ K^$ is measured to be $(1.54 \pm 0.04 \pm 0.11) \times 10^{4}$. This is the most precise result to date, due to the largest $\psi(3686)$ sample, improved signal reconstruction efficiency, good simulation of the detector performance, and a more accurate knowledge of the continuum contribution. Using the branching fraction of $J/\psi \to \omega K^+ K^$, the ratio $\mathcal{B}(\psi(3868) \to K^+K^) / \mathcal{B}(J/\psi \to K^+K^)$ is determined to be $(18.4 \pm 3.7)\,\%$. This constitutes a significantly improved test of the $12\,\%$ rule, with the uncertainty now dominated by the $J/\psi$ branching fraction.05/2014;  [Show abstract] [Hide abstract]
ABSTRACT: An energy scan near the $\tau$ pair production threshold has been performed using the BESIII detector. About $24$ pb$^{1}$ of data, distributed over four scan points, was collected. This analysis is based on $\tau$ pair decays to $ee$, $e\mu$, $eh$, $\mu\mu$, $\mu h$, $hh$, $e\rho$, $\mu\rho$ and $\pi\rho$ final states, where $h$ denotes a charged $\pi$ or $K$. The mass of the $\tau$ lepton is measured from a maximum likelihood fit to the $\tau$ pair production cross section data to be $m_{\tau} = (1776.91\pm0.12 ^{+0.10}_{0.13}$) MeV/$c^2$, which is currently the most precise value in a single measurement.Physical Review D 05/2014; 90(1). · 4.69 Impact Factor 
Article: Measurement of the $D\to K^\pi^+$ strong phase difference in $\psi(3770)\to D^0\overline{D}{}^0$
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ABSTRACT: We study $D^0\overline{D}{}^0$ pairs produced in $e^+e^$ collisions at $\sqrt{s}=3.773$ GeV using a data sample of 2.92 fb$^{1}$ collected with the BESIII detector. We measure the asymmetry $\mathcal{A}^{CP}_{K\pi}$ of the branching fractions of $D \to K^\pi^+$ in $CP$odd and $CP$even eigenstates to be $(12.7\pm1.3\pm0.7)\times10^{2}$. $\mathcal{A}^{CP}_{K\pi}$ can be used to extract the strong phase difference $\delta_{K\pi}$ between the doubly Cabibbosuppressed process $\overline{D}{}^{0}\to K^\pi^+$ and the Cabibbofavored process $D^0\to K^ \pi^+$. Using worldaverage values of external parameters, we obtain $\cos\delta_{K\pi} = 1.02\pm0.11\pm0.06\pm0.01$. Here, the first and second uncertainties are statistical and systematic, respectively, while the third uncertainty arises from the external parameters. This is the most precise measurement of $\delta_{K\pi}$ to date.04/2014;  [Show abstract] [Hide abstract]
ABSTRACT: We study the process e+e→(D*D¯*)±π∓ at a centerofmass energy of 4.26 GeV using a 827 pb1 data sample obtained with the BESIII detector at the Beijing Electron Positron Collider. Based on a partial reconstruction technique, the Born cross section is measured to be (137±9±15) pb. We observe a structure near the (D*D¯*)± threshold in the π∓ recoil mass spectrum, which we denote as the Zc±(4025). The measured mass and width of the structure are (4026.3±2.6±3.7) MeV/c2 and (24.8±5.6±7.7) MeV, respectively. Its production ratio σ(e+e→Zc±(4025)π∓→(D*D¯*)±π∓)/σ(e+e→(D*D¯*)±π∓) is determined to be 0.65±0.09±0.06. The first uncertainties are statistical and the second are systematic.Physical Review Letters 04/2014; 112(13):132001. · 7.73 Impact Factor  [Show abstract] [Hide abstract]
ABSTRACT: Using a sample of $1.3\times 10^9$ $J/\psi$ events collected with the BESIII detector, we report the first observation of $\eta^{\prime}\to\pi^{+}\pi^{}\pi^{+}\pi^{}$ and $\eta^{\prime}\to\pi^{+}\pi^{}\pi^{0}\pi^{0}$. The measured branching fractions are $\mathcal{B}$($\eta^{\prime}\to\pi^{+}\pi^{}\pi^{+}\pi^{}$) = $(8.41\pm0.68({\rm stat.})\pm0.63({\rm syst.}))\times10^{5}$ and $\mathcal{B}$($\eta^{\prime}\to\pi^{+}\pi^{}\pi^{0}\pi^{0}$) = $(1.90\pm0.36({\rm stat.})\pm0.19({\rm syst.}))\times10^{4}$, which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vectormeson dominance.03/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Based on a sample of (225.3\pm2.8)\times 10^{6} J/\psi events collected with the BESIII detector, the electromagnetic Dalitz decays of J/\psi \to P e^+e^(P=\eta'/\eta/\pi^0) are studied. By reconstructing the pseudoscalar mesons in various decay modes, the decays J/\psi \to \eta' e^+e^, J/\psi \to \eta e^+e^ and J/\psi \to \pi^0 e^+e^ are observed for the first time. The branching fractions are determined to be \mathcal{B}(J/\psi\to \eta' e^+e^) = (5.81\pm0.16\pm0.31)\times10^{5}, \mathcal{B}(J/\psi\to \eta e^+e^) = (1.16\pm0.07\pm0.06)\times10^{5}, and \mathcal{B}(J/\psi\to \pi^0 e^+e^)=(7.56\pm1.32\pm0.50)\times10^{7}, where the first errors are statistical and the second ones systematic.03/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using 2917 $\rm{pb}^{1}$ of data accumulated at 3.773~$\rm{GeV}$, 44.5~$\rm{pb}^{1}$ of data accumulated at 3.65~$\rm{GeV}$ and data accumulated during a $\psi(3770)$ lineshape scan with the BESIII detector, the reaction $e^+e^\rightarrow p\bar{p}$ is studied considering a possible interference between resonant and continuum amplitudes. The cross section of $e^+e^\rightarrow\psi(3770)\rightarrow p\bar{p}$, $\sigma(e^+e^\rightarrow\psi(3770)\rightarrow p\bar{p})$, is found to have two solutions, determined to be ($0.059\pm0.032\pm0.012$) pb with the phase angle $\phi = (255.8\pm37.9\pm4.8)^\circ$ ($<$0.11 pb at the 90% confidence level), or $\sigma(e^+e^\rightarrow\psi(3770)\rightarrow p\bar{p}) = (2.57\pm0.12\pm0.12$) pb with $\phi = (266.9\pm6.1\pm0.9)^\circ$ both of which agree with a destructive interference. Using the obtained cross section of $\psi(3770)\rightarrow p\bar{p}$, the cross section of $p\bar{p}\rightarrow \psi(3770)$, which is useful information for the future PANDA experiment, is estimated to be either ($9.8\pm5.7$) nb ($<17.2$ nb at 90% C.L.) or $(425.6\pm42.9)$ nb.03/2014;  [Show abstract] [Hide abstract]
ABSTRACT: With data samples collected with the BESIII detector operating at the BEPCII storage ring at centerofmass energies from 4.009 to 4.420 GeV, the process e+e→γX(3872) is observed for the first time with a statistical significance of 6.3σ. The measured mass of the X(3872) is (3871.9±0.7stat±0.2syst) MeV/c2, in agreement with previous measurements. Measurements of the product of the cross section σ[e+e→γX(3872)] and the branching fraction B[X(3872)→π+πJ/ψ] at centerofmass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260)→γX(3872).Physical Review Letters 03/2014; 112(9):092001. · 7.73 Impact Factor  [Show abstract] [Hide abstract]
ABSTRACT: A search for the rare decays of $J/\psi \to D_s^\rho^+ + c.c.$ and $J/\psi \to \overline{D}{}^0\overline{K}{}^{\ast0} + c.c.$ is performed with a data sample of 225.3 million $J/\psi$ events collected with the BESIII detector. No evident signal is observed. Upper limits on the branching fractions are determined to be $\mathcal{B}(J/\psi \to D_s^\rho^+ + c.c.) < 1.3 \times 10^{5}$ and $\mathcal{B}(J/\psi \to \overline{D}{}^0\overline{K}{}^{\ast0} + c.c.) < 2.5 \times 10^{6}$ at the $90\%$ confidence level.02/2014;  [Show abstract] [Hide abstract]
ABSTRACT: Using $(106.41\pm 0.86) \times 10^{6}$ $\psi(3686)$ events collected with the BESIII detector at BEPCII, we study for the first time the decay $\chi_{cJ}\to\eta'K^+K^$, where $\eta'\to\gamma\rho^{0}$ and $\eta'\to\eta\pi^+\pi^$. A partial wave analysis in the covariant tensor amplitude formalism is performed for the decay $\chi_{c1}\to\eta'K^+K^$. Intermediate processes $\chi_{c1}\to\eta' f_0(980)$, $\chi_{c1}\to\eta' f_0(1710)$, $\chi_{c1}\to\eta' f_2'(1525)$ and $\chi_{c1}\to K^*_0(1430)^{\pm}K^{\mp}$ ($K^*_0(1430)^{\pm}\to\eta' K^{\pm}$) are observed with statistical significances larger than 5$\sigma$, and their branching fractions are measured.02/2014;  [Show abstract] [Hide abstract]
ABSTRACT: We report on a study of the process e^{+}e^{}→π^{±}(DD[over ¯]^{*})^{∓} at sqrt[s]=4.26 GeV using a 525 pb^{1} data sample collected with the BESIII detector at the BEPCII storage ring. A distinct charged structure is observed in the (DD[over ¯]^{*})^{∓} invariant mass distribution. When fitted to a massdependentwidth BreitWigner line shape, the pole mass and width are determined to be M_{pole}=(3883.9±1.5(stat)±4.2(syst)) MeV/c^{2} and Γ_{pole}=(24.8±3.3(stat)±11.0(syst)) MeV. The mass and width of the structure, which we refer to as Z_{c}(3885), are 2σ and 1σ, respectively, below those of the Z_{c}(3900)→π^{±}J/ψ peak observed by BESIII and Belle in π^{+}π^{}J/ψ final states produced at the same centerofmass energy. The angular distribution of the πZ_{c}(3885) system favors a J^{P}=1^{+} quantum number assignment for the structure and disfavors 1^{} or 0^{}. The Born cross section times the DD[over ¯]^{*} branching fraction of the Z_{c}(3885) is measured to be σ(e^{+}e^{}→π^{±}Z_{c}(3885)^{∓})×B(Z_{c}(3885)^{∓}→(DD[over ¯]^{*})^{∓})=(83.5±6.6(stat)±22.0(syst)) pb. Assuming the Z_{c}(3885)→DD[over ¯]^{*} signal reported here and the Z_{c}(3900)→πJ/ψ signal are from the same source, the partial width ratio (Γ(Z_{c}(3885)→DD[over ¯]^{*})/Γ(Z_{c}(3900)→πJ/ψ))=6.2±1.1(stat)±2.7(syst) is determined.Physical Review Letters 01/2014; 112(2):022001. · 7.73 Impact Factor
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7  Citations  
87.16  Total Impact Points  
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Institutions

2012

University of Science and Technology of China
Luchow, Anhui Sheng, China
