Eta-etaprime mixing in eta-mesic nuclei

Eta bound states in nuclei are sensitive to the flavour-singlet component in the eta. The bigger the singlet component, the more attraction and the greater the binding. eta-etaprime mixing plays an important role in understanding the value of the eta-nucleon scattering length a_{\eta N}. Working with the Quark Meson Coupling model, we find a factor of two enhancement from mixing relative to the prediction with a pure octet eta.