Evidence for η_{c}(2S) in ψ(3686) \to γK_{S}^{0}K^{\pm}π^{\mp}π^{+}π^{-}

Abstract

We search for the M1 radiative transition ψ(3686) \to γη_{c}(2S) by reconstructing the exclusive η_{c}(2S) \to K_{S}^{0}K^{\pm}π^{\mp}π^{+}π^{-} decay using 1.06 \times 10^8 ψ(3686) events collected with the BESIII detector. The signal is observed with a statistical significance of greater than 4 standard deviations. The measured mass of the η_{c}(2S) is 3646.9 \pm 1.6(stat) \pm 3.6(syst) MeV/c^2, and the width is 9.9 \pm 4.8(stat) \pm 2.9(syst) MeV/c^2. The product branching fraction is measured to be B(ψ(3686) \to γη_{c}(2S)) \times B(η_{c}(2S) \to K_{S}^{0}K^{\pm}π^{\mp}π^{+}π^{-}) = (7.03 \pm 2.10(stat) \pm 0.70(syst)) \times 10^{-6}. This measurement complements a previous BESIII measurement of ψ(3686) \to γη_{c}(2S) with η_{c}(2S) \to K_{S}^{0} K^{\pm}π^{\mp} and K^{+}K^{-}π^{0}.

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
• Search for hadronic transition ${\chi }_{cJ}\to {\eta }_c{\pi }^{+}{\pi }^{-}$ and observation of ${\chi }_{cJ}\to K\bar{K}\pi \pi \pi$
• Branching fraction measurements of χ_{c0} and χ_{c2} to π^0π^0 and ηη
• Observation of the eta_c(2S) in exclusive B-->K KsK-pi+ decays
• Study of ${\chi }_{cJ}$ radiative decays into a vector meson
• Observation of eta_c^{prime} Production in gamma gamma Fusion at CLEO
• J/psi and psi(2S) Radiative Transitions to eta_c
• Measurements of the mass and width of the eta_c meson and of an eta_c(2S) candidate
• Measurement of B(J/psi->eta_c gamma) at KEDR
• Observation of ${\chi }_{c1}$ decays into vector meson pairs $\varphi \varphi$, $\omega \omega$, and $\omega \varphi$
• Observation of eta_c(1S) and eta_c(2S) decays to K+ K- pi+ pi- pi0 in two-photon interactions
• Search for ${\eta }_c^{\prime }$ decays into vector meson pairs

Cited by in corpus (13)

• Confirmation of a charged charmoniumlike state $Z_c(3885{)}^{\mp }$ in $e^{+}{e}^{-}\to {\pi }^{\pm }(D{\bar{D}}^{\ast }{)}^{\mp }$ with double $D$ tag
• Observation of a Neutral Structure near the $D{\bar{D}}^{\ast }$ Mass Threshold in $e^{+}{e}^{-}\to (D{\bar{D}}^{\ast }{)}^0{\pi }^0$ at $\sqrt{s}$ = 4.226 and 4.257 GeV
• Search for the $Y(4140)$ via $e^{+}{e}^{-}\to \gamma \varphi J/\psi$ at $\sqrt{s}=$ 4.23, 4.26 and 4.36 GeV
• Study of charmonium production in $b$-hadron decays and first evidence for the decay $B_s^0\to \varphi \varphi \varphi$
• New puzzle in charmonium decays
• Observation of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\psi (3770)$ and $D_1(2420{)}^0{\bar{D}}^0+c.c.$
• Evidence for $e^{+}{e}^{-}\to \gamma {\eta }_c(1S)$ at center-of-mass energies between 4.01 and 4.60 GeV
• A QCD sum rules calculation of the ${\eta }_c{D}^{\ast }D$ and ${\eta }_c{D}_s^{\ast }{D}_s$ form factors and strong coupling constants
• Measurement of the branching fraction for $\psi (3686)\to \omega K^{+}{K}^{-}$
• Observation of the decays ${\chi }_{cJ}\to \varphi \varphi \eta$
• Searches for isospin-violating transitions ${\chi }_{c0,2}\to {\pi }^0{\eta }_c$
• Search for the radiative transitions $\psi (3770)\to \gamma {\eta }_c$ and $\gamma {\eta }_c(2S)$
• Charmonium and light hadron spectroscopy