2010/09/20 by Jennifer M. Stone, Ellen G. Zweibel
Physics and Astronomy · #Ambipolar diffusion #Astrophysics and Star Formation Studies #Bistability #Convection #Diffusion #Front (military) #Interstellar medium #Magnetic field #Optical properties and cooling technologies in crystalline materials #Quantum, superfluid, helium dynamics #Thermal #Thermal diffusivity #astro-ph.GA
paper · pdf · doi:10.1088/0004-637x/724/1/131
17 pages, 12 figures, 1 table, accepted for publication in ApJ
arxiv created 2010/09/20 · openalex publication_date 2010/10/28 · arxiv updated 2015/05/20 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
In a thermally bistable medium, cold, dense gas is separated from warm, rarefied gas by thin phase transition layers, or fronts, in which heating, radiative cooling, thermal conduction, and convection of material are balanced. We calculate the steady-state structure of such fronts in the presence of magnetic fields, including the processes of ion–neutral drift and ion–neutral frictional heating. We find that ambipolar diffusion efficiently transports the magnetic field across the fronts, leading to a flat magnetic field strength profile. The thermal profiles of such fronts are not significantly different from those of unmagnetized fronts. The near uniformity of the magnetic field strength across a front is consistent with the flat field strength–gas density relation that is observed in diffuse interstellar gas.