2008/09/02 by Y. Rasera, Yann Rasera, Benjamin Chandran +1
Physics and Astronomy · #Anisotropy #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Buoyancy #Convection #Cosmic ray #Galaxy #Galaxy cluster #Intracluster medium #Plasma #Solar and Space Plasma Dynamics #Thermal conduction #astro-ph
paper · pdf · doi:10.1086/591012
40 pages, 10 figures, 1 table, accepted for publication in ApJ
arxiv created 2008/09/02 · openalex publication_date 2008/09/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
In clusters of galaxies, the specific entropy of intracluster plasma increases outward. Nevertheless, a number of recent studies have shown that the intracluster medium is subject to buoyancy instabilities due to the effects of cosmic rays and anisotropic thermal conduction. In this paper we present a new numerical algorithm for simulating such instabilities. This numerical method treats the cosmic rays as a fluid, accounts for the diffusion of heat and cosmic rays along magnetic field lines, and enforces the condition that the temperature and cosmic-ray pressure remain positive. We carry out several tests to ensure the accuracy of the code, including the detailed matching of analytic results for the eigenfunctions and growth rates of linear buoyancy stabilities. This numerical scheme will be useful for simulating convection driven by cosmic-ray buoyancy in galaxy cluster plasmas and may also be useful for other applications, including fusion plasmas, the interstellar medium, and supernova remnants.