Equation of state of superfluid neutron matter with low-momentum interactions

Abstract

In this work, we calculate the ground state energy of pure neutron matter using the renormalization group based low-momentum effective interaction $V_{\text{low-}k}$ in Bogoliubov many-body perturbation theory (BMBPT), which is a perturbative expansion around the Hartree-Fock-Bogoliubov (HFB) ground state. In order to capture the low-density behavior of neutron matter, it turns out to be better to use a density dependent cutoff in the $V_{\text{low-}k}$ interaction. Perturbative corrections to the HFB energy up to third order are included. We find that at low densities corresponding to the inner crust of neutron stars, the HFB state that includes pairing is a better starting point for perturbation expansion. It is observed that including the higher order perturbative corrections, the cutoff dependence of the ground state energy is reduced.

11 pages, 6 figures. MBPT results with discussions and references added

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Cited by in corpus (7)

• Bayesian inference of neutron star crust properties using an ab initio-benchmarked meta-model
• New Skyrme parametrizations to describe finite nuclei and neutron star matter with realistic effective masses
• Effect of the equation of state for dilute neutron matter on the composition of the inner crust of neutron stars
• Effects of dilute neutron matter on the neutron star crust equation of state
• Induced three-neutron interactions with low cutoffs for dilute neutron matter
• Ab initio Bogoliubov many-body perturbation theory: closed-form constraint on the average particle number
• Hartree shift and pairing gap in ultracold Fermi gases in the framework of low-momentum interactions