Nuclear pairing from microscopic forces: singlet channels and higher-partial waves

Abstract

Background: An accurate description of nuclear pairing gaps is extremely important for understanding static and dynamic properties of the inner crusts of neutron stars and to explain their cooling process. Purpose: We plan to study the behavior of the pairing gaps ${\Delta }_F$ as a function of the Fermi momentum $k_F$ for neutron and nuclear matter in all relevant angular momentum channels where superfluidity is believed to naturally emerge. The calculations will employ realistic chiral nucleon-nucleon potentials with the inclusion of three-body forces and self-energy effects. Methods: The superfluid states of neutron and nuclear matter are studied by solving the BCS gap equation for chiral nuclear potentials using the method suggested by Khodel et al., where the original gap equation is replaced by a coupled set of equations for the dimensionless gap function $\chi (p)$ defined by $\Delta (p)={\Delta }_F\chi (p)$ and a non-linear algebraic equation for the gap magnitude ${\Delta }_F=\Delta (p_F)$ at the Fermi surface. This method is numerically stable even for small pairing gaps, such as that encountered in the coupled ${}^{3}P{F}_2$ partial wave. Results: We have successfully applied Khodel's method to singlet ($S$) and coupled channel ($SD$ and $PF$) cases in neutron and nuclear matter. Our calculations agree with other ab-initio approaches, where available, and provide crucial inputs for future applications in superfluid systems.

18 pages and 9 figures

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• Density-dependent nucleon-nucleon interaction from three-nucleon forces
• Low Momentum Nucleon-Nucleon Interactions and Shell-Model Calculations
• Dependence of the BCS 1S0 superfluid pairing gap on nuclear interactions
• Microscopic evaluation of the pairing gap

Cited by in corpus (11)

• Superfluidity and Superconductivity in Neutron Stars
• Pairing in neutron matter: New uncertainty estimates and three-body forces
• Pairing and short-range correlations in nuclear systems
• Comparison between the Thomas-Fermi and Hartree-Fock-Bogoliubov Methods in the Inner Crust of a Neutron Star: The Role of Pairing Correlations
• Three-nucleon forces and superfluidity in neutron matter
• Spin-polarized phases of ${}^3{P}_2$ superfluids in neutron stars
• Core structures of vortices in Ginzburg-Landau theory for neutron ${}^3{P}_2$ superfluids
• Superfluid neutron matter with a twist
• Symmetry classification of uniform states in spin-2 Bose-Einstein condensates and neutron ${}^3{P}_2$ superfluids
• Cold atoms beyond atomic physics
• Isospin-Asymmetry Dependence of the Thermodynamic Nuclear Equation of State in Many-Body Perturbation Theory