Translationally invariant treatment of pair correlations in nuclei: I.   Spin and isospin dependent correlations
  We study the extension of our translationally invariant treatment of few-body nuclear systems to heavier nuclei. At the same time we also introduce state-dependent correlation operators. Our techniques are tailored to those nuclei that can be dealt with in $LS$ coupling, which includes all nuclei up to the shell closure at $A=40$. We study mainly $p$-shell nuclei in this paper. A detailed comparison with other microscopic many-body approaches is made, using a variety of schematic nuclear interactions. It is shown that our methodology produces very good energies, and presumably also wave functions, for medium mass nuclei. 
R. Guardiola, P. I. Moliner, J. Navarro, R.F. Bishop, A. Puente, Niels   R. Walet