E. E. Saperstein — Page 3

arXiv2001

Can weakly bound heavy nuclei with very large neutron excess exist?

A realistic model is suggested based on the quasiparticle Lagrange version of the self-consistent Finite Fermi Systems theory supplemented with the microscopically calculated surface parameters of the Landau-Migdal interaction amplitude. The latter are expressed in terms of the off-shell T-matrix of free NN-scattering and show a strong dependence on the chemical potential of a nucleus under consideration in the drip line vicinity. This effect could result in shifting the neutron drip line position to very large values of the neutron excess.

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arXiv2001

The Local Potential Approximation for the Brueckner G-matrix

The Brueckner G-matrix for a slab of nuclear matter is analyzed in the singlet $^1S$ and triplet $^3S+^3D$ channels. The complete Hilbert space is split into two domains, the model subspace $S_0$, in which the two-particle propagator is calculated explicitly, and the complementary one, $S'$, in which the local potential approximation is used. This kind of local approximation was previously found to be quite accurate for the $^1S$ pairing problem. A set of model spaces $S_0(E_0)$ with different values of the cut-off energy $E_0$ is considered, $E_0$ being the upper limit for the single-particle energies of the states belonging to $S_0$. The independence of the G-matrix of $E_0$ is assumed as a criterion of validity of the local potential approximation. Such independence is obtained within few percent for $E_0=10 ÷20$ MeV for both the channels under consideration.

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