Transition from BCS pairing to Bose-Einstein condensation in low-density asymmetric nuclear matter
Abstract
We study the isospin-singlet neutron-proton pairing in bulk nuclear matter as a function of density and isospin asymmetry within the BCS formalism. In the high-density, weak-coupling regime the neutron-proton paired state is strongly suppressed by a minor neutron excess. As the system is diluted, the BCS state with large, overlapping Cooper pairs evolves smoothly into a Bose-Einstein condensate of tightly bound neutron-proton pairs (deuterons). In the resulting low-density system a neutron excess is ineffective in quenching the pair correlations because of the large spatial separation of the deuterons and neutrons. As a result, the Bose-Einstein condensation of deuterons is weakly affected by an additional gas of free neutrons even at very large asymmetries.
Keywords
Cite
@article{arxiv.nucl-th/0109024,
title = {Transition from BCS pairing to Bose-Einstein condensation in low-density asymmetric nuclear matter},
author = {U. Lombardo and P. Nozieres and P. Schuck and H. -J. Schulze and A. Sedrakian},
journal= {arXiv preprint arXiv:nucl-th/0109024},
year = {2009}
}
Comments
17 pages, uncluding 7 figures, PRC in press