Collective Modes in a Superfluid Neutron Gas within the Quasiparticle Random-Phase Approximation
arXiv:1406.0335 · doi:10.1103/PhysRevC.90.065805
Abstract
We study collective excitations in a superfluid neutron gas at zero temperature within the quasiparticle random phase approximation. The particle-hole residual interaction is obtained from a Skyrme functional, while a separable interaction is used in the pairing channel which gives a realistic density dependence of the pairing gap. In accordance with the Goldstone theorem, we find an ungapped collective mode (analogous to the Bogoliubov-Anderson mode). At low momentum, its dispersion relation is approximately linear and its slope coincides with the hydrodynamic speed of sound calculated with the Skyrme equation of state. The response functions are compared with those obtained within the Landau approximation. We also compute the contribution of the collective mode to the specific heat of the neutron gas, which is relevant for the thermodynamic properties of the inner crust of neutron stars.
12 pages
References in corpus (8)
- Strongly paired fermions: Cold atoms and neutron matter
- Low-momentum interactions with smooth cutoffs
- Low-energy collective excitations in the neutron star inner crust
- Superfluid Heat Conduction and the Cooling of Magnetized Neutron Stars
- Unified description of neutron superfluidity in the neutron-star crust with analogy to anisotropic multi-band BCS superconductors
- Dependence of the BCS 1S0 superfluid pairing gap on nuclear interactions
- Temperature and finite-size effects in collective modes of superfluid Fermi gases
- Response functions of cold neutron matter: density, spin and current fluctuations
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- Elementary excitations in homogeneous superfluid neutron star matter: role of the neutron-proton coupling
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- Roton instabilities in the superfluid outer core of neutron stars
- Dynamical scheme for computing the mass parameter of a system in a medium