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${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit c}}}$ MESONS
(including possibly non-${\mathit {\mathit q}}$ ${\mathit {\overline{\mathit q}}}$ states)

INSPIRE JSON PDGID:

${{\mathit \eta}_{{{c}}}{(2S)}}$

$I^G(J^{PC})$ = $0^+(0^{- +})$

Quantum numbers are quark model predictions.

${{\mathit \eta}_{{{c}}}{(2S)}}$ MASS

$3637.8$ $\pm0.6$ MeV (S = 1.1)

${{\mathit \eta}_{{{c}}}{(2S)}}$ WIDTH

$11.6$ $\pm1.4$ MeV

${{\mathit \eta}_{{{c}}}{(2S)}}$ DECAY MODES

Mode

Fraction ($\Gamma_i$ / $\Gamma$)

Scale Factor/
Conf. Level

P(MeV/c)

${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}}$

($1.9^{+1.2}_{-1.0}$ ) $\%$

${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \eta}}$

($7^{+5}_{-4}$) $ \times 10^{-3}$

2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$

$<2.6$ $\times 10^{-3}$

${{\mathit a}_{{{0}}}{(1450)}}{{\mathit \pi}}$

${{\mathit a}_{{{2}}}{(1700)}}{{\mathit \pi}}$

${{\mathit a}_{{{0}}}{(1710)}}{{\mathit \pi}}$

${{\mathit \rho}^{0}}{{\mathit \rho}^{0}}$

$<2.3$ $\times 10^{-3}$

3 ${{\mathit \pi}^{+}}$3 ${{\mathit \pi}^{-}}$

($1.7^{+0.9}_{-1.1}$ ) $\%$

${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

$<2.5$ $\times 10^{-3}$

${{\mathit K}^{*0}}{{\overline{\mathit K}}^{*0}}$

$<4$ $\times 10^{-3}$

${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$

($1.5^{+1.0}_{-0.9}$ ) $\%$

${{\mathit K}^{+}}{{\mathit K}^{-}}$2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$

${{\mathit K}_S^0}$ ${{\mathit K}^{-}}$2 ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ + c.c.

($1.4^{+0.8}_{-1.0}$ ) $\%$

2 ${{\mathit K}^{+}}$2 ${{\mathit K}^{-}}$

$<1.4$ $\times 10^{-3}$

${{\mathit K}_{{{2}}}^{*}{(1430)}}{{\overline{\mathit K}}}$ + c.c.

${{\mathit K}_{{{0}}}^{*}{(1950)}}{{\overline{\mathit K}}}$ + c.c.

${{\mathit K}_{{{0}}}^{*}{(2600)}}{{\overline{\mathit K}}}$ + c.c.

${{\mathit \phi}}{{\mathit \phi}}$

$<1.4$ $\times 10^{-3}$

${{\mathit p}}{{\overline{\mathit p}}}$

$<3.2$ $\times 10^{-4}$

${{\mathit p}}{{\overline{\mathit p}}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

${{\mathit \gamma}}{{\mathit \gamma}}$

($1.8^{+1.0}_{-1.1}$) $ \times 10^{-4}$

${{\mathit \gamma}}{{\mathit J / \psi}{(1S)}}$

${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}}$

($5.5^{+3.3}_{-4.0}$) $ \times 10^{-3}$

${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}^{\,'}}$

($2.7^{+2.0}_{-1.8}$) $ \times 10^{-3}$

${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}_{{{c}}}{(1S)}}$

Constrained Fit information

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