OUR FIT includes measurements of ${\mathit m}_{{{\mathit \psi}{(2S)}}}$, ${\mathit m}_{{{\mathit \psi}{(3770)}}}$, and ${\mathit m}_{{{\mathit \psi}{(3770)}}}{\mathit m}_{{{\mathit \psi}{(2S)}}}$.
3
Mass central value and systematic error recalculated by us according to Eq.$~$(16) in ARMSTRONG 1993B, using the value for the ${{\mathit J / \psi}{(1S)}}$ mass from AULCHENKO 2003.
4
From a fit of a relativistic ${\mathit S}{\mathrm -wave}$ Breit-Wigner convolved with the detector resolution. The width of ${{\mathit \psi}{(2S)}}$ is constrained to the PDG 2022 value. Systematic errors not evaluated.
5
From the scans in 2004 and 2006. ANASHIN 2012 reports the value $3686.114$ $\pm0.007$ $\pm0.011$ ${}^{+0.002}_{-0.012}$ MeV, where the third uncertainty is due to assumptions on the interference between the resonance and hadronic continuum. We combined the two systematic uncertainties.