Observation of the $X(1840)$ at BESIII

Abstract

Observation of the $X(1840)$ in the $3({\pi }^{+}{\pi }^{-})$ invariant mass in $J/\psi \to \gamma 3({\pi }^{+}{\pi }^{-})$ at BESIII is reviewed. With a sample of $225.3\times 10^6$ $J/\psi$ events collected with the BESIII detector at BEPCII, the $X(1840)$ is observed with a statistical significance of $7.6\sigma$. The mass, width and product branching fraction of the $X(1840)$ are determined. The decay ${\eta }^{\prime }\to 3({\pi }^{+}{\pi }^{-})$ is searched for, and the upper limit of the branching fraction is set at the 90% confidence level.

4 pages, 3 figures, proceeding of PIC2013

References in corpus (6)

• Confirmation of the X(1835) and observation of the resonances X(2120) and X(2370) in J/psi->gamma pi^+pi^-eta'
• Spin-Parity Analysis of ppbar Mass Threshold Structure in J/psi and psi' Radiative Decays
• Study of psi(2S) Decays to gamma p bar{p}, pi^0 p bar{p} and eta p bar{p} and Search for p bar{p} Threshold Enhancements
• Study of the near-threshold $\omega \varphi$ mass enhancement in doubly OZI suppressed $J/\psi \to \gamma \omega \varphi$ decays
• Study of resonant structure around 1.8 GeV/$c^2$ and $\eta (1405)$ in $J/\psi \to \omega \eta {\pi }^{+}{\pi }^{-}$
• Observation of a structure at 1.84 GeV/c${}^2$ in the $3({\pi }^{+}{\pi }^{-})$ mass spectrum in $J/\psi \to \gamma 3({\pi }^{+}{\pi }^{-})$ decays