University of Helsinki
Columbia University
California Institute of Technology
Canadian Institute for Theoretical Astrophysics
University of Toronto
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., βp ≫ 1 (hydrodynamic regime). In contrast, when βp ≲ 1 (magnetohydrodynamic regime), the flow is dominated by a global lattice of effectively fixed magnetic islands (plasmoids) without any jets. Understanding the spatiotemporal variability of dynamic atmospheres and oceans on neutron stars is crucial for interpreting observations of their X-ray emissions.
© 2024. The Author(s). Published by the American Astronomical Society.
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
The authors thank Valentin Skoutnev for helpful discussions. J.N. is supported by the European Union (ERC, ILLUMINATOR, 101114623). The views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. J.W.S. is supported by NASA grant 80NSSC23K0345 and a Simons Foundation Pivot Fellowship. Support for this work was provided by NASA through the NASA Hubble Fellowship grant HST-HF2-51518.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Part of this work was performed at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-2210452.
| Name | Size | Download all |
|---|---|---|
|
md5:cec3815cdfe3da1c9a0e309e662763b4
|
662.5 kB | Preview Download |
