Hydrodynamic simulations of clumps

A. Feldmeier, W.-R. Hamann, D. Rätzel & L. M. Oskinova

Universität Potsdam, Institut für Physik, Astrophysik

Clumps in hot star winds can originate from shock compression due to the line driven instability. One-dimensional hydrodynamic simulations reveal a radial wind structure consisting of highly compressed shells separated by voids, and colliding with fast clouds. Two-dimensional simulations are still largely missing, despite first attempts. Clumpiness dramatically affects the radiative transfer and thus all wind diagnostics in the UV, optical, and in X-rays. The microturbulence approximation applied hitherto is currently superseded by a more sophisticated radiative transfer in stochastic media. Besides clumps, i.e. jumps in the density stratification, so-called kinks in the velocity law, i.e. jumps in dv/dr, play an eminent role in hot star winds. Kinks are a new type of radiative-acoustic shock, and propagate at super-Abbottic speed.

The full article is available as PostScript file via anonymous ftp.
Server: ftp.astro.physik.uni-potsdam.de
user: anonymous or ftp; Password: your e-mail address;
file: /usr/aftp/pub/wrhamann/workshop/feldmeier.ps (350kB PostScript uncompressed)
or feldmeier.ps.gz (180kB PostScript compressed)
or feldmeier.pdf (180kB)

Display full article with ghostview (local users only!)

Fetch PostScript-File (feldmeier.ps, 350kB, uncompressed)

Fetch PostScript-File (feldmeier.ps.gz, 180kB, compressed)

Fetch Pdf-File (feldmeier.pdf, 180kB, uncompressed)

Zurück zur Übersicht