Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra

Details Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra

2005-03-16

arxiv.org/abs/astro-ph/0503342v1

Astrophys.J. 638 (2006) 1086-1100

Astronomy and Astrophysics

Astrophysics

13 pages, 10 figures, submitted to ApJ

Scientific paper

10.1086/499117

A forward model is described in which we synthesize spectra from an ab-initio 3D MHD simulation of an outer stellar atmosphere, where the coronal heating is based on braiding of magnetic flux due to photospheric footpoint motions. We discuss the validity of assumptions such as ionization equilibrium and investigate the applicability of diagnostics like the differential emission measure inversion. We find that the general appearance of the synthesized corona is similar to the solar corona and that, on a statistical basis, integral quantities such as average Doppler shifts or differential emission measures are reproduced remarkably well. The persistent redshifts in the transition region, which have puzzled theorists since their discovery, are explained by this model as caused by the flows induced by the heating through braiding of magnetic flux. While the model corona is only slowly evolving in intensity, as is observed, the amount of structure and variability in Doppler shift is very large. This emphasizes the need for fast coronal spectroscopy, as the dynamical response of the corona to the heating process manifests itself in a comparably slow evolving coronal intensity but rapid changes in Doppler shift.

Affiliated with

Also associated with

No associations

Rating

Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Forward modeling of stellar coronae: from a 3D MHD model to synthetic EUV spectra will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-569457