Observation of ${\eta }_c\to \omega \omega$ in $J/\psi \to \gamma \omega \omega$

Abstract

Using a sample of $(1310.6\pm 7.0)\times 10^6$ $J/\psi$ events recorded with the BESIII detector at the symmetric electron positron collider BEPCII, we report the observation of the decay of the $(1^1{S}_0)$ charmonium state ${\eta }_c$ into a pair of $\omega$ mesons in the process $J/\psi \to \gamma \omega \omega$. The branching fraction is measured for the first time to be $\mathcal{B}({\eta }_c\to \omega \omega )=(2.88\pm 0.10\pm 0.46\pm 0.68)\times 10^{-3}$, where the first uncertainty is statistical, the second systematic and the third is from the uncertainty of $\mathcal{B}(J/\psi \to \gamma {\eta }_c)$. The mass and width of the ${\eta }_c$ are determined as $M=(2985.9\pm 0.7\pm 2.1)$MeV/$c^2$ and $\Gamma =(33.8\pm 1.6\pm 4.1)$MeV.

arXiv comment13 pages, 6 figures

References in corpus (14)

• Design and Construction of the BESIII Detector
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations
• Model-independent Study of Magnetic Dipole Transitions in Quarkonium
• J/psi and psi(2S) Radiative Transitions to eta_c
• Determination of the number of $J/\psi$ events with inclusive $J/\psi$ decays
• Study of $\psi (3686)\to {\pi }^0{h}_c,h_c\to \gamma {\eta }_c$ via ${\eta }_c$ exclusive decays
• Multivariate side-band subtraction using probabilistic event weights
• Higher-order multipole amplitudes in charmonium radiative transitions
• Pseudoscalar Quarkonium Exclusive Decays to Vector Meson Pair
• Observation of new resonant structures in $\gamma \gamma \to \omega \varphi$, $\varphi \varphi$ and $\omega \omega$
• Measurement of J/psi to eta_c gamma at KEDR
• Measurement of Branching Ratios for ${\eta }_c$ Hadronic Decays
• Experimental study of \etac decays into vector-vector final states

Cited by in corpus (5)

• Determination of spin-parity quantum numbers of X(2370) as $0^{-+}$ from $J/\psi \to \gamma K_S^0{K}_S^0{\eta }^{\prime }$
• Observation of the Doubly Cabibbo-Suppressed Decay $D^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\pi }^0$ and Evidence for $D^{+}\to K^{+}\omega$
• Cross section measurements of $e^{+}{e}^{-}\to \Phi K^{+}{K}^{-}$ and $e^{+}{e}^{-}\to \Phi K_S^0{K}_S^0$ at center-of-mass energies between 3.7730 GeV and 4.7008 GeV
• Study of the Magnetic Dipole Transition of $J/\psi \to \gamma {\eta }_c$ via ${\eta }_c\to p\bar{p}$
• Amplitude Analysis of the Isospin-Violating Decay $J/\psi \to \gamma \eta {\pi }^0$