The Prediction of Possible Nonstrange Dibaryon

Recently, the mixing of scalar mesons was introduced into the chiral SU(3) quark model and also dynamically applied to the baryon-baryon system. The results show that the nucleon-nucleon and hyperon-nucleon scattering data can be reasonably described for different mixing cases, one is ideal mixing and the other is θ_s=19° mixing. In the present work, by taking the above parameters, the possible candidate of deltaron bound state is further predicted. We find that the contributions from σ and ε exchange to binding energy of deltaron are different, that the contribution from ε exchange is negligible, and that σ exchange is dominant. We also find that the binding energy of deltaron is very stable, around several tens of MeV, no matter what kind of mixing is adopted.