Eur. Phys. J. A (2014) 50: 103
https://doi.org/10.1140/epja/i2014-14103-1

Regular Article - Theoretical Physics

Prediction of a Z_c(4000) state and relationship with the claimed Z_c(4025)

¹ Departamento de Física Teórica, Universidad de Valencia and IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Aptdo. 22085, 46071, Valencia, Spain
² Department of Physics, Kocaeli University, 41380, Izmit, Turkey
³ Instituto de Física, Universidade de São Paulo, C. P. 66318, 05389-970, São Paulo, SP, Brasil

^* e-mail: aceti@ific.uv.es

Received: 13 January 2014
Revised: 13 January 2014
Accepted: 19 May 2014
Published online: 25 June 2014

Abstract

After discussing the OZI suppression of one light meson exchange in the interaction of with isospin I = 1 , we study the contribution of the two-pion exchange to the interaction and the exchange of heavy vectors, J/ψ for diagonal transitions and D^* for transitions of to J/ψ ρ. We find these latter mechanisms to be weak, but enough to barely bind the system in J = 2 with a mass around 4000 MeV, while the effect of the two-pion exchange is a net attraction, though weaker than that from heavy-vector exchange. We discuss this state and try to relate it to the Z _c (4025) state, above the threshold, claimed in an experiment at BES from an enhancement of the distribution close to threshold. Together with the results from a recent reanalysis of the BES experiment showing that it is compatible with a J = 2 state below threshold around 3990 MeV, we conclude that the BES experiment could show the existence of the state that we find in our approach.