Publications (739)1591.52 Total impact

Article: The Physics of the B Factories
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ABSTRACT: This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C.European Physical Journal C 11/2014; · 5.25 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). · 4.86 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  [Show abstract] [Hide abstract]
ABSTRACT: We study e^{+}e^{}→π^{+}π^{}h_{c} at centerofmass energies from 3.90 to 4.42 GeV by using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections are measured at 13 energies and are found to be of the same order of magnitude as those of e^{+}e^{}→π^{+}π^{}J/ψ but with a different line shape. In the π^{±}h_{c} mass spectrum, a distinct structure, referred to as Z_{c}(4020), is observed at 4.02 GeV/c^{2}. The Z_{c}(4020) carries an electric charge and couples to charmonium. A fit to the π^{±}h_{c} invariant mass spectrum, neglecting possible interferences, results in a mass of (4022.9±0.8±2.7) MeV/c^{2} and a width of (7.9±2.7±2.6) MeV for the Z_{c}(4020), where the first errors are statistical and the second systematic. The difference between the parameters of this structure and the Z_{c}(4025) observed in the D^{*}D[over ¯]^{*} final state is within 1.5σ, but whether they are the same state needs further investigation. No significant Z_{c}(3900) signal is observed, and upper limits on the Z_{c}(3900) production cross sections in π^{±}h_{c} at centerofmass energies of 4.23 and 4.26 GeV are set.Physical Review Letters 12/2013; 111(24):242001. · 7.73 Impact Factor  [Show abstract] [Hide abstract]
ABSTRACT: We report a measurement of the branching fraction $B(D^+ \rightarrow \mu^+ \nu_{\mu}) = [3.71 \pm 0.19 (\rm stat) \pm 0.06 (\rm sys)]\times 10^{4}$ based on 2.92 ${\rm fb^{1}}$ of data accumulated at $\sqrt{s}=3.773$ GeV with the BESIII detector at the BEPCII collider. This measurement, in conjunction with the CKM matrix element $V_{\rm cd}$ determined from a global Standard Model fit, implies a value for the weak decay constant $f_{D^+}=(203.2 \pm 5.3 \pm 1.8)$ MeV. Additionally, using this branching fraction measurement together with a Lattice QCD prediction for $f_{D^+}$, we find $V_{\rm cd}=0.2210\pm 0.0058 \pm 0.0047$. In either case, these are the most precise results for these quantities to date.12/2013; 
Article: Observation of the decay $\psi(3686)$ $\rightarrow$ $\Lambda\bar\Sigma^{\pm}\pi^{\mp}+c.c.$
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ABSTRACT: Using a sample of $1.06\times10^{8}$ $\psi(3686)$ events collected with the BESIII detector, we present the first observation of the decays of $\psi(3686)$ $\rightarrow$ $\Lambda\bar\Sigma^{+}\pi^{}+c.c.$ and $\psi(3686)$ $\rightarrow$ $\Lambda\bar\Sigma^{}\pi^{+}+c.c.$. The branching fractions are measured to be $\mathcal{B}(\psi(3686) \rightarrow \Lambda\bar\Sigma^{+}\pi^{} + c.c.)=(1.40\pm 0.03 \pm 0.13)\times10^{4}$ and $\mathcal{B}(\psi(3686) \rightarrow \Lambda\bar\Sigma^{}\pi^{+}+c.c.)=(1.54\pm 0.04 \pm 0.13)\times10^{4}$, where the first errors are statistical and the second ones systematic.10/2013;  [Show abstract] [Hide abstract]
ABSTRACT: 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 determined to be $\mathcal{B}(\psi(3686)\to\gamma\eta_c(2S))\times\mathcal{B}(\eta_{c}(2S)\to p\bar{p})<1.4\times10^{6}$ and $\mathcal{B}(\psi(3686)\to\pi^0h_c)\times\mathcal{B}(h_{c}\to p\bar{p})<1.3\times10^{7}$ at the 90% C.L.. The branching fractions for $\chi_{cJ}\to p\bar{p}$ $(J=0,~1,~2)$ are also measured to be $(24.5\pm0.8\pm1.3,~8.6\pm0.5\pm0.5,~8.4\pm0.5\pm0.5)\times10^{5}$, which are the world's most precise measurements until now.10/2013;  [Show abstract] [Hide abstract]
ABSTRACT: Using data samples collected with the BESIII detector operating at the BEPCII storage ring at centerofmass energies from 4.009 to 4.420 GeV, $e^{+} e^{} \to \gamma X(3872)$ is observed for the first time with a statistical significance of $6.3\sigma$. The measured mass of X(3872) is ($3871.9\pm 0.7_{\rm stat.}\pm 0.2_{\rm sys.}$) MeV/c$^2$, in agreement with previous measurements. The products of the cross section $\sigma[e^{+} e^{} \to \gamma X(3872)]$ and the branching ratio $\mathcal{B}[X(3872) \to \pi^{+} \pi^{} J/\psi]$ at centerofmass energies 4.009, 4.229, 4.260, and 4.360 GeV are also measured.10/2013;  [Show abstract] [Hide abstract]
ABSTRACT: We study e+e > pi+pih_c at centerofmass energies from 3.90 GeV to 4.42 GeV using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections are measured at 13 energies, and are found to be of the same order of magnitude as those of e+e > pi+piJ/psi but with a different line shape. In the \pi^\pm h_c mass spectrum, a distinct structure, referred to as Z_c(4020), is observed at 4.02 GeV/c^2. The Z_c(4020) carries an electric charge and couples to charmonium. A fit to the \pi^\pm h_c invariant mass spectrum, neglecting possible interferences, results in a mass of (4022.9\pm 0.8\pm 2.7) MeV/c^2 and a width of (7.9\pm 2.7\pm 2.6) MeV for the Z_c(4020), where the first errors are statistical and the second systematic. No significant Z_c(3900) signal is observed, and upper limits on the Z_c(3900) production cross sections in \pi^\pm h_c at centerofmass energies of 4.23 and 4.26 GeV are set.09/2013;
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2k  Citations  
1,591.52  Total Impact Points  
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Institutions

2002–2012

Institute of physics china
Peping, Beijing, China


2005–2010

Government of the People's Republic of China
Peping, Beijing, China


2006

University of Maryland, College Park
Maryland, United States


2003

Stanford University
Palo Alto, California, United States


2000

Technical Institute of Physics and Chemistry
Peping, Beijing, China
