The state χc0(3915) has recently been demoted by the Particle Data Group from its previous status as the conventional cc 23P0 state, largely due to the absence of expected DD decays. We propose that χc0(3915) is actually the lightest ccss state, and calculate the spectrum of such states using the diquark model, identifying many of the observed charmoniumlike states that lack open-charm decay modes as ccss. Among other results, we argue that Y(4140) is a JPC=1++ ccss state that has been not been seen in two-photon fusion largely as a consequence of the Landau-Yang theorem.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)