Observation of the $\psi (1^3{D}_2)$ state in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\gamma {\chi }_{c1}$ at BESIII

Abstract

We report the observation of the $X(3823)$ in the process $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}X(3823)\to {\pi }^{+}{\pi }^{-}\gamma {\chi }_{c1}$ with a statistical significance of $6.2\sigma$, in data samples at center-of-mass energies $\sqrt{s}=$4.230, 4.260, 4.360, 4.420 and 4.600~GeV collected with the BESIII detector at the BEPCII electron positron collider. The measured mass of the $X(3823)$ is $(3821.7\pm 1.3\pm 0.7)$~MeV/$c^2$, where the first error is statistical and the second systematic, and the width is less than $16$~MeV at the 90\% confidence level. The products of the Born cross sections for $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}X(3823)$ and the branching ratio $\mathcal{B}[X(3823)\to \gamma {\chi }_{c1,c2}]$ are also measured. These measurements are in good agreement with the assignment of the $X(3823)$ as the $\psi (1^3{D}_2)$ charmonium state.

7 pages, 3 figures, version to appear in Phys. Rev. Lett

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• Big-Bang Nucleosynthesis
• Heavy quarkonium: progress, puzzles, and opportunities
• Observation of $e^{+}{e}^{-}\to \eta J/\psi$ at center-of-mass energy $sqrts=4.009$ GeV
• Trigger efficiencies at BES III

Cited by in corpus (11)

• STCF Conceptual Design Report: Volume 1 -- Physics & Detector
• Charmonium spectrum and their electromagnetic transitions with higher multipole contributions
• Observation of resonance structures in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{\psi }_2(3823)$ and mass measurement of ${\psi }_2(3823)$
• Measurement of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{D}^{+}{D}^{-}$ cross sections at center-of-mass energies from 4.190 to 4.946 GeV
• Charmonium: Conventional and $XYZ$ States in a Relativistic Screened Potential Model
• The electromagnetic decays of $X(3823)$ as the ${\psi }_2(1^3{D}_2)$ state and its radial excited states
• The process $e^{+}{e}^{-}\to \pi \pi X(3823)$ in the soft pion limit
• Search for the ${\eta }_{c2}(1D)$ in $e^{+}{e}^{-}\to \gamma {\eta }_{c2}(1D)$ at $\sqrt{s}$ near 10.6 GeV at Belle
• Systematic analysis of the transition form factors of $B_c$ to $D$-wave charmonia and corresponding semileptonic decays
• Prospects for observing the missing $2D$ and $1F$ charmonium states around 4 GeV
• Systematic analysis of the D-wave charmonium states with the QCD sum rules