2016/01/15 by A. F. Fantina, N. Chamel, Y. D. Mutafchieva +4
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics #High-pressure geophysics and materials #Magnetar #Neutron #Neutron star #Nuclear drip line #Nuclear physics #Nucleosynthesis #Physics #Pulsars and Gravitational Waves Research #Saturation (graph theory) #Stars #astro-ph.HE #nucl-th #s-process
paper · pdf · doi:10.1103/physrevc.93.015801
published as Phys. Rev. C 93, 015801 (2016) · 29 pages, 9 figures
openalex publication_date 2016/01/15 · arxiv created 2021/03/10 · arxiv updated 2021/03/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this paper, we study the role of the symmetry energy on the neutron-drip transition in both nonaccreting and accreting neutron stars, allowing for the presence of a strong magnetic field as in magnetars. The density, pressure, and composition at the neutron-drip threshold are determined using the recent set of the Brussels-Montreal microscopic nuclear mass models, which mainly differ in their predictions for the value of the symmetry energy J and its slope L in infinite homogeneous nuclear matter at saturation. Although some correlations between on the one hand the neutron-drip density, the pressure, the proton fraction, and on the other hand J (or equivalently L) are found, these correlations are radically different in nonaccreting and accreting neutron stars. In particular, the neutron-drip density is found to increase with L in the former case, but decreases in the latter case depending on the composition of ashes from x-ray bursts and superbursts. We have qualitatively explained these different behaviors using a simple mass formula. We have also shown that the details of the nuclear structure may play a more important role than the symmetry energy in accreting neutron-star crusts.