We describe the main features of our most recent Hartree-Fock-Bogoliubov nuclear mass models , based on 16-parameter generalized Skyrme forces .
They have been fitted to the data of the 2012 Atomic Mass Evaluation , and favour a value of 30 MeV for the symmetry coefficient J , the corresponding root-mean square deviation being 0.549 MeV .
We find that this conclusion is compatible with measurements of neutron-skin thickness .
By constraining the underlying interactions to fit various equations of state of neutron matter calculated ab initio our models are well adapted to a realistic and unified treatment of all regions of neutron stars .
We use our models to calculate the composition , the equation of state , the mass-radius relation and the maximum mass .
Comparison with observations of neutron stars again favours a value of J = 30 MeV .