Open AccessMultifluid numerical models of wind‐swept clumps
Author(s) -
Lim A. J.,
Raga A. C.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02253.x
Subject(s) - physics , ionization , astrophysics , bow shock (aerodynamics) , shock (circulatory) , plasma , spectral line , shock wave , balmer series , ion , atomic physics , supernova , emission spectrum , astronomy , mechanics , medicine , quantum mechanics
We present 2D axisymmetric numerical models of the dynamics of a multifluid interaction between a high‐velocity rarefied wind of ionization fraction 0.5 and dense clumps of varying ionization fraction. The difference in the relative ram pressure acting on the neutral and ionic components of the clump results in a separation between the ionic and neutral bow shocks, which is an order of magnitude larger than that which would be expected from the different pressure to density ratios of the ions and neutrals. This results in the neutral bow shock leading for a low‐ionization clump, and the ionic shock leading for a high‐ionization clump. Simulated long‐slit Hα spectra are calculated for each of three clump ionization fractions. For higher levels of clump ionization a narrow component at the preshock speed is clearly seen in the emission profile. Such a component is typically seen in spectroscopic observations of the Balmer filaments of supernova remnants.