General predictions for the neutron star crustal moment of inertia
Résumé
The neutron star crustal equation of state and transition point properties are computed within a unified metamodeling approach. A Bayesian approach is employed including two types of filters: Bulk nuclear properties are controlled from low-density effective field-theory predictions as well as the present knowledge from nuclear experiments, whereas the surface energy is adjusted on experimental nuclear masses. Considering these constraints, a quantitative prediction of crustal properties can be reached with controlled confidence intervals and increased precision with respect to previous calculations: ≈11% dispersion on the crustal width and ≈27% dispersion on the fractional moment of inertia. The crust moment of inertia is also evaluated as a function of the neutron star mass, and predictions for mass and radii are given for different pulsars. The origin of Vela pulsar glitches is discussed, and a full crustal origin is excluded if we consider the present largest estimation of crustal entrainment. Further refinement of the present predictions requires a better estimation of the high-order isovector empirical parameters, e.g., Ksym and Qsym, and a better control of the surface properties of extremely neutron rich nuclei.
Origine : Fichiers éditeurs autorisés sur une archive ouverte