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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:

${{\mathit \psi}{(2S)}}$

$I^G(J^{PC})$ = $0^-(1^{- -})$

See the Review on ``Branching Ratios of ${{\mathit \psi}{(2S)}}$, ${{\mathit \chi}}_{c0,1,2}$ and ${{\mathit \eta}_{{{c}}}{(1S)}}$'' before the ${{\mathit \chi}_{{{c0}}}{(1P)}}$ Listings.

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${{\mathit \psi}{(2S)}}$ MASS

$3686.097$ $\pm0.010$ MeV

${\mathit m}_{{{\mathit \psi}{(2S)}}}-{\mathit m}_{{{\mathit J / \psi}{(1S)}}}$

$589.188$ $\pm0.028$ MeV

${{\mathit \psi}{(2S)}}$ WIDTH

$286$ $\pm16$ keV

▸ MULTIPOLE AMPLITUDE RATIOS IN RADIATIVE DECAYS ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{{cJ}}}{(1P)}}$ and ${{\mathit \chi}_{{{cJ}}}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit J / \psi}{(1S)}}$

${{\mathit \psi}{(2S)}}$ DECAY MODES

Mode

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

Scale Factor/
Conf. Level

P(MeV/c)

($97.85$ $\pm0.13$ ) $\%$

virtual ${{\mathit \gamma}}$ $\rightarrow$ hadrons

($1.79$ $\pm0.04$ ) $\%$

${{\mathit g}}{{\mathit g}}{{\mathit g}}$

($10.6$ $\pm1.6$ ) $\%$

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

($1.03$ $\pm0.29$ ) $\%$

($15.4$ $\pm1.5$ ) $\%$

${{\mathit K}_S^0}$ anything

($16.0$ $\pm1.1$ ) $\%$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

($7.94$ $\pm0.22$) $ \times 10^{-3}$

${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$

($8.0$ $\pm0.6$) $ \times 10^{-3}$

${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$

($3.1$ $\pm0.4$) $ \times 10^{-3}$

▸ Decays into ${{\mathit J / \psi}{(1S)}}$ and anything

▸ Hadronic decays

▸ Radiative decays

▸ Weak decays

▸ Other decays

[1]	${{\mathit \Theta}{(1540)}}$ is a hypothetical pentaquark state of 1.54 GeV/c${}^{2}$ mass and a width of less than 25 MeV/c${}^{2}$.
[2]	See the ``Note on the ${{\mathit \eta}{(1405)}}$'' in the ${{\mathit \eta}{(1405)}}$ Particle Listings.
[3]	For a narrow resonance in the range 2.2 $<$ ${{\mathit M}}({{\mathit X}}$) $<$ 2.8 GeV.

Constrained Fit information

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