2017/09/30 by Yeunhwan Lim, Jeremy W. Holt · 14 citations
Earth and Planetary Sciences · Physics and Astronomy · #BCS theory #Effective field theory #High-pressure geophysics and materials #Mean field theory #Neutron #Neutron star #Nuclear physics #Nuclear physics research studies #Pairing #Perturbation theory (quantum mechanics) #Physics #Proton #Pulsars and Gravitational Waves Research #Quantum electrodynamics #Quantum mechanics #Superconductivity #nucl-th
paper · pdf · doi:10.1103/physrevc.103.025807
published in Physical Review C 103(2) (American Institute of Physics) · 8 pages, 9 figures
arxiv created 2021/02/12 · openalex publication_date 2021/02/22 · arxiv updated 2021/03/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We study the 1S0 proton pairing gap in \ensuremathβ-equilibrated neutron star matter within the framework of chiral effective field theory. We focus on the role of three-body forces, which strongly modify the effective proton-proton spin-singlet interaction in dense matter. We find that three-body forces generically reduce both the size of the pairing gap and the maximum density at which proton pairing may occur. The pairing gap is computed within Bardeen-Cooper-Schrieffer theory using a single-particle dispersion relation calculated up to second order in perturbation theory. Model uncertainties are estimated by varying the nuclear potential (its order in the chiral expansion and high-momentum cutoff) and the choice of single-particle spectrum in the gap equation. We find that a second-order perturbative treatment of the single-particle spectrum suppresses the proton 1S0 pairing gap relative to the use of a free spectrum. We estimate the critical temperature for the onset of proton superconductivity to be Tc=(3.2--5.1)\ifmmode×\else\texttimes\fi109 K, which is consistent with previous theoretical results in the literature and marginally within the range deduced from a recent Bayesian analysis of neutron star cooling observations.