English

Neutron Star Atmosphere-Ocean Dynamics

High Energy Astrophysical Phenomena 2024-06-06 v2 Solar and Stellar Astrophysics

Abstract

We analyze the structure and dynamics of the plasma atmospheres and Coulomb-liquid oceans on neutron stars. Salient dynamical parameters are identified and their values estimated for the governing set of magnetohydrodynamics equations. Neutron star atmospheres and oceans are strongly stratified and, depending on the rotation period, contain a multitude of long-lived vortices (spots) and/or narrow zonal jets (free-shear zones) in the large plasma-beta regime - i.e., βp1\beta_p \gg 1 (hydrodynamic regime). In contrast, when βp1\beta_p \lesssim 1 (magnetohydrodynamic regime), the flow is dominated by a global lattice of effectively fixed magnetic islands (plasmoids) - without any jets. Understanding the spatio-temporal variability of dynamic atmospheres and oceans on neutron stars is crucial for interpreting observations of their X-ray emissions.

Keywords

Cite

@article{arxiv.2306.08186,
  title  = {Neutron Star Atmosphere-Ocean Dynamics},
  author = {Joonas Nättilä and James Y-K. Cho and Jack W. Skinner and Elias R. Most and Bart Ripperda},
  journal= {arXiv preprint arXiv:2306.08186},
  year   = {2024}
}

Comments

15 pages, 6 figures, 2 appendices. Accepted to ApJ

R2 v1 2026-06-28T11:04:33.149Z