${\chi }_{c1}(2p)$: an overshadowed charmoniumlike resonance

Abstract

A thorough study of the $J^{PC}=1^{++}$ elastic $D^0{\bar{D}}^{\ast 0}$ and $D^{+}{D}^{\ast -}$ scattering, where the form of the meson-meson interaction is inferred from lattice QCD calculations of string breaking, is carried out for center-of-mass energies up to 4 GeV. We show that the presence of ${\chi }_{c1}(3872)$, which can be naturally assigned to either a bound or virtual charmoniumlike state close below the $D^0{\bar{D}}^{\ast 0}$ threshold, can overshadow a quasiconventional charmoniumlike resonance lying above threshold. This makes difficult the experimental detection of this resonance through the $D^0{\bar{D}}^{\ast 0}$ and $D^{+}{D}^{\ast -}$ channels, despite being its expected main decay modes. We analyze alternative strong and electromagnetic decay modes. Comparison with existing data shows that this resonance may have already been observed through its decay to $\omega J/\psi$.

Comments: 23 pages, 12 figures; v2: updated figures, expanded text, new references, updated acknowledgements, additional minor changes; v3: version accepted for publication in JHEP, format change to single column, major additions to sections 2 and 3, section 6 has become section 5 and it has been expanded with a new subsection, one new figure, updated bibliography, other minor modifications