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arXiv · 1403.0167

Observation of the $X(1840)$ at BESIII

Jingqing Zhang
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Abstract

Observation of the $X(1840)$ in the $3(π^+π^-)$ invariant mass in $J/ψ\rightarrowγ3(π^+π^-)$ at BESIII is reviewed. With a sample of $225.3\times10^6$ $J/ψ$ events collected with the BESIII detector at BEPCII, the $X(1840)$ is observed with a statistical significance of $7.6σ$. The mass, width and product branching fraction of the $X(1840)$ are determined. The decay $η^\prime\rightarrow 3(π^+π^-)$ is searched for, and the upper limit of the branching fraction is set at the 90% confidence level.

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Jingqing Zhang. 2014-03-02. Observation of the $X(1840)$ at BESIII. https://doi.org/10.1142/s2010194514603111

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