${\boldsymbol {\boldsymbol c}}$ ${\boldsymbol {\overline{\boldsymbol c}}}$ MESONS(including possibly non- ${\boldsymbol {\boldsymbol q}}$ ${\boldsymbol {\overline{\boldsymbol q}}}$ states) INSPIRE search

${{\boldsymbol \psi}{(4260)}}$ $I^G(J^{PC})$ = $0^-(1^{- -})$

also known as ${{\mathit Y}{(4260)}}$; was ${{\mathit X}{(4260)}}$
The state ${{\mathit \psi}{(4260)}}$ received its mass label from a Breit-Wigner (BW) fit to the ${{\mathit J / \psi}}{{\mathit \pi}}{{\mathit \pi}}$ data listed below. The symmetric BW placed the mass unavoidably into the center of the distribution. The most recent measurement in the 4260 MeV mass range in the same channel (ABLIKIM 2017B), however, revealed that the distribution is asymmetric and that the state has a much lower mass consistent with the entry for particle ${{\mathit \psi}{(4230)}}$. Thus, in this edition we merged the measurement of ABLIKIM 2017B with the ${{\mathit \psi}{(4230)}}$ node and labeled the older measurements of this node as not used. For details see the review on "Spectroscopy of mesons containing two heavy quarks."