Charmionium (quark c and antiquark c bonded state)

State	Energy [MeV]
?c(1S)	2979.7 ą 1.5
?c(2S)	3594 ą 5
J/?(1S)	3096.87 ą 0.04
?(2S)	3685.96 ą 0.09
?c0(1P)	3415.1 ą 0.8
?c1(1P)	3510.51 ą 0.12
?c2(1P)	3556.16 ą 0.13

 
Source: Particles and fields, Phys. Rev. D., Vol. 66, No 1-I, 2002, p. 719

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