ForumSpringerAstron. Astrophys.
ForumWhats NewSearchOrders

Astron. Astrophys. 317, 244-247 (1997)

Table of Contents
Available formats: HTML | PDF (152 KB) | (gzipped) PostScript (175 KB)

On H[FORMULA] source function vertical variations in filaments
and bright rims visibility

Frédéric Paletou

1 Institut d'Astrophysique Spatiale, Université de Paris XI, Bâtiment 121, F-91405 Orsay Cedex, France
2 Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, N-0315 Oslo, Norway

Received 5 December 1995 / Accepted 15 May 1996


Using new radiative modelling capabilities in two-dimensional (2D) cartesian geometry, we investigate the vertical variations of the H [FORMULA] source function in filaments. It is shown how the two-dimensional geometry can affect the transfer of the H [FORMULA] line into filaments and, consequently, how assumptions on the geometry of the model may influence a further interpretation of observations. A special attention is paid to the possibility of formation of a bright rim inside the filament body by diffusive penetration of H [FORMULA] radiation. Unlike recently proposed by Heinzel et al. (1995), we can see from our 2D computations that the observable emergent intensities are not high enough to explain bright rims contrasts.

Key words: radiative transfer — Sun: prominences — Sun: filaments

Present address: Observatoire de la Côte d'Azur, Laboratoire G.D. Cassini, B.P. 229, F-06304 Nice Cedex 4, France

Send offprint requests to: paletou@obs-nice.fr

© European Southern Observatory (ESO) 1997