The (3985) as a Threshold Effect From the Interaction
Natsumi Ikeno (Departamento de Física Teórica, IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Valencia, Spain, Department of Agricultural, Life and Environmental Sciences, Tottori University, Tottori, Japan)
; Raquel Molina (Departamento de Física Teórica, IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Valencia, Spain); Eulogio Oset (Departamento de Física Teórica, IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Valencia, Spain)
We study the reaction recently measured at BESIII, from where a new state has been reported. We study the interaction of with the coupled channels , , , by means of an extension to the charm sector of the local hidden gauge approach. We find that the combination couples to and , but the combination does not. The coupled channels help to build up strength in the diagonal scattering matrix close to threshold and, although the interaction is not strong enough to produce a bound state or resonance, it is sufficient to produce a large accumulation of strength at the threshold in the reaction in agreement with experiment.