Observation of χc1\chi_{c1} decays into vector meson pairs ϕϕ\phi\phi, ωω\omega\omega, and ωϕ\omega\phi

Decays of $\chi_{c1}$ to vector meson pairs $\phi\phi$, $\omega\omega$ and $\omega\phi$ are observed for the first time using $(106\pm4)\times 10^6$ \psip events accumulated at the BESIII detector at the BEPCII $e^+e^-$ collider. The branching fractions are measured to be $(4.4\pm 0.3\pm 0.5)\times 10^{-4}$, $(6.0\pm 0.3\pm 0.7)\times 10^{-4}$, and $(2.2\pm 0.6\pm 0.2)\times 10^{-5}$, for $\chi_{c1}\to \phi\phi$, $\omega\omega$, and $\omega\phi$, respectively. The observation of $\chi_{c1}$ decays into a pair of vector mesons $\phi\phi$, $\omega\omega$ and $\omega\phi$ indicates that the hadron helicity selection rule is significantly violated in $\chi_{cJ}$ decays. In addition, the measurement of $\chi_{cJ}\to \omega\phi$ gives the rate of doubly OZI-suppressed decay. Branching fractions for $\chi_{c0}$ and $\chi_{c2}$ decays into other vector meson pairs are also measured with improved precision.Comment: 4 pages, 2 figure

Evidence for e+e−→γχc1,2e^+e^-\to\gamma\chi_{c1, 2} at center-of-mass energies from 4.009 to 4.360 GeV

Using data samples collected at center-of-mass 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 center-of-mass energy.Comment: 8 pages, 7 figures, 3 table

Improved measurement of the absolute branching fraction of D+→Kˉ0μ+νμD^{+}\rightarrow \bar K^0 \mu^{+}\nu_{\mu}

By analyzing 2.93 fb$^{-1}$ of data collected at $\sqrt s=3.773$ GeV with the BESIII detector, we measure the absolute branching fraction ${\mathcal B}(D^{+}\rightarrow\bar K^0\mu^{+}\nu_{\mu})=(8.72 \pm 0.07_{\rm stat.} \pm 0.18_{\rm sys.})\%$, which is consistent with previous measurements within uncertainties but with significantly improved precision. Combining the Particle Data Group values of ${\mathcal B}(D^0\to K^-\mu^+\nu_\mu)$, ${\mathcal B}(D^{+}\rightarrow\bar K^0 e^{+}\nu_{e})$, and the lifetimes of the $D^0$ and $D^+$ mesons with the value of ${\mathcal B}(D^{+}\rightarrow\bar K^0 \mu^{+}\nu_{\mu})$ measured in this work, we determine the following ratios of partial widths: $\Gamma(D^0\to K^-\mu^+\nu_\mu)/\Gamma(D^{+}\rightarrow\bar K^0\mu^{+}\nu_{\mu})=0.963\pm0.044$ and $\Gamma(D^{+}\rightarrow\bar K^0 \mu^{+}\nu_{\mu})/\Gamma(D^{+}\rightarrow\bar K^0 e^{+}\nu_{e})=0.988\pm0.033$.Comment: 9 pages; 8 figure

Measurement of the W+W− cross section in pp collisions at s√=7 TeV and limits on anomalous WWγ and WWZ couplings

A measurement of W+W− production in pp collisions at s√=7 TeV is presented. The data were collected with the CMS detector at the LHC, and correspond to an integrated luminosity of 4.92±0.11 fb−1. The W+W− candidates consist of two oppositely charged leptons, electrons or muons, accompanied by large missing transverse energy. The W+W− production cross section is measured to be 52.4±2.0 (stat.)±4.5 (syst.)±1.2 (lum.) pb. This measurement is consistent with the standard model prediction of 47.0±2.0 pb at next-to-leading order. Stringent limits on the WWγ and WWZ anomalous triple gauge-boson couplings are set

Detection of SARS-associated Coronavirus in Throat Wash and Saliva in Early Diagnosis

Early detection of SARS-CoV in throat wash and saliva suggests that these specimens are ideal for SARS diagnosis

Efficacy and safety of combination therapy with vildagliptin and metformin versus metformin up-titration in Chinese patients with type 2 diabetes mellitus: study design and rationale of the vision study

Background and aim: Limitations of the currently recommended stepwise treatment pathway for type 2 diabetes mellitus (T2DM), especially the failure of monotherapies to maintain good glycemic control, have prompted use of early, more aggressive combination therapies. The VISION study is designed to explore the efficacy and safety of vildagliptin as an add-on to metformin therapy compared with up-titration of metformin monotherapy in Chinese patients with T2DM. Methods: VISION, a 24-week, phase 4, prospective, randomized, multicenter, open-label, parallel-group study, will include 3312 Chinese T2DM patients aged >= 18 years who are inadequately controlled (6.5% >HbA1c <= 9%) by metformin (750-1000 mg/day). Eligible patients will be randomized to receive either vildagliptin plus metformin or up-titration of metformin monotherapy (5: 1). Patients will also be subgrouped (1: 1: 1: 1) based on their age and body mass index (BMI): <60 years and <24 kg/m(2); <60 years and >= 24 kg/m(2); >= 60 years and <24 kg/m(2); and >= 60 years and >= 24 kg/m(2). Conclusion: The VISION study will test the hypothesis that early use of combination therapy with vildagliptin and metformin will provide good glycemic control and will be better tolerated than up-titration of metformin monotherapy. The study will also correlate these benefits with age and BMI.Cardiac & Cardiovascular SystemsEndocrinology & MetabolismSCI(E)PubMed1ARTICLE1181

Precision measurements of branching fractions for ψ′→π0Jψ \psi'\to\pi^0 J\psi and ηJψ\eta J\psi

We present a precision study of the \psip\to\pi^0 J/\psi and $\eta J/\psi$ decay modes. The measurements are obtained using $106\times10^6$ $\psi'$ events accumulated with the BESIII detector at the BEPCII \ee collider operating at a center-of-mass energy corresponding to the \psip mass. We obtain \mathcal{B}(\psip\to\pi^0 J/\psi)=(1.26\pm0.02{\rm (stat.)}\pm0.03{\rm (syst.)})\times 10^{-3} and \mathcal{B}(\psip\to\eta J/\psi)=(33.75\pm0.17{\rm (stat.)}\pm0.86{\rm (syst.)})\times 10^{-3}. The branching fraction ratio R=\frac{\mathcal{B}(\psip\to\pi^0 J/\psi)}{\mathcal{B}(\psip\to\eta J/\psi)} is determined to be $(3.74\pm0.06 {\rm(stat.)}\pm0.04 {\rm(syst.)})\times 10^{-2}$. The precision of these measurements of \mathcal{B}(\psip\to\pi^{0} J/\psi) and $R$ represent a significant improvement over previously published values.Comment: four figures, 12 page

Study of e+e−→2(pp¯) at center-of-mass energies between 4.0 and 4.6 GeV

Using data taken at 23 center-of-mass energies between 4.0 and 4.6 GeV with the BESIII detector at the Beijing Electron Positron Collider and with a total integrated luminosity of approximately 15 fb-1, the process e+e-→2(pp¯) is studied for the first time. The Born cross sections for e+e-→2(pp¯) are measured, and no significant structure is observed in the lineshape. The baryon pair (pp and p¯p¯) invariant mass spectra are consistent with phase space, therefore no hexaquark or di-baryon state is found

Observation of Electromagnetic Dalitz decays J/\psi \to P e^+e^-

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

Cross section measurement of e+e−→pp¯η and e+e−→pp¯ω at center-of-mass energies between 3.773 GeV and 4.6 GeV

Based on 14.7 fb-1 of e+e- annihilation data collected with the BESIII detector at the BEPCII collider at 17 different center-of-mass energies between 3.7730 GeV and 4.5995 GeV, Born cross sections of the two processes e+e-→pp¯η and e+e-→pp¯ω are measured for the first time. No indication of resonant production through a vector state V is observed, and upper limits on the Born cross sections of e+e-→V→pp¯η and e+e-→V→pp¯ω at the 90% confidence level are calculated for a large parameter space in resonance masses and widths. For the current world average parameters of the ψ(4230) of m=4.2187 GeV/c2 and Γ=44 MeV, we find upper limits on resonant production of the pp¯η and pp¯ω final states of 7.5 pb and 10.4 pb at the 90% CL, respectively