Degeneracies in a nonintegrable pairing model
  The evolution pattern of exceptional points is studied in a non-integrable limit of the complex-extended 3-level Richardson-Gaudin model. The appearance of a pseudo-diabolic point from the fusion of two exceptional points is demonstrated in the anti-hermitian limit of the model and studied in some details. 
J. Okolowicz, M. Ploszajczak, J. Dukelsky