Recent experimental and ab initio theory investigations of the 208Pb neutron skin thickness have the potential to inform the neutron star equation of state. In particular, the strong correlation between the 208Pb neutron skin thickness and the pressure of neutron matter at normal nuclear densities leads to modified predictions for the radii, tidal deformabilities, and moments of inertia of typical 1.4M⊙ neutron stars. In the present work, we study the relative impact of these recent analyses of the 208Pb neutron skin thickness on bulk properties of neutron stars within a Bayesian statistical analysis. Two models for the equation of state prior are employed in order to highlight the role of the highly uncertain high-density equation of state. From our combined Bayesian analysis of nuclear theory, nuclear experiment, and observational constraints on the dense matter equation of state, we find at the 90% credibility level R1.4=12.36−0.73+0.38 km for the radius of a 1.4M⊙ neutron star, R2.0=11.96−0.71+0.94 km for the radius of a 2.0M⊙ neutron star, Λ1.4=440−144+103 for the tidal deformability of a 1.4M⊙ neutron star, and I1.338=1.425−0.146+0.074×1045gcm2 for the moment of inertia of PSR J0737-3039A whose mass is 1.338M⊙.
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Constraints on the Nuclear Symmetry Energy from Experiments, Theory and Observations
Abstract Nuclear mass measurements and neutron matter theory tightly constrain the nuclear symmetry energy parametersJ,L,KsymandQsym. Corroboration of these constraints onJandLcan be found from measurements of the neutron skin thicknesses and dipole polarizabilities of neutron-rich nuclei. The experimental constraints on these parameters are compared with those obtained from consideration of astrophysical measurements of the neutron star radius, which we show is highly correlated withL. Attention is aimed at the recent PREX and CREX neutron skin measurements from Jefferson Lab, NICER neutron star radius measurements, and a new interpretation of the GW170817 tidal deformability measurement. We find joint satisfaction of PREX and CREX givesJ= 32.2 ± 1.7 MeV andL= 52.9 ± 13.2 MeV, in excellent agreement with neutron matter predictions ofJ= 32.0±1.1 MeV andL= 51.9±7.9 MeV.
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- Award ID(s):
- 2020275
- PAR ID:
- 10610433
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Journal of Physics: Conference Series
- Volume:
- 2536
- Issue:
- 1
- ISSN:
- 1742-6588
- Page Range / eLocation ID:
- 012009
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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