Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity

Details Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity

2005-02-03

arxiv.org/abs/astro-ph/0502063v1

Astrophys.J. 621 (2005) L125-L128

Astronomy and Astrophysics

Astrophysics

13 pages, 3 figures, to be published in ApJ Letters

Scientific paper

10.1086/429288

X-ray spectra of the late-type star AB Dor, obtained with the XMM-Newton satellite are analysed. AB Dor was particularly active during the observations. An emission measure reconstruction technique is employed to analyse flare and quiescent spectra, with emphasis on the Fe XVII 15-17 A wavelength region. The Fe XVII 16.78 A/15.01 A line ratio increases significantly in the hotter flare plasma. This change in the ratio is opposite to the theoretical predictions and is attributed to the scattering of 15.01 A line photons from the line-of-sight. The escape probability technique indicates an optical depth of about 0.4 for the 15.01 A line. During the flare, the electron density is 4.4*10^10 cm^-3 and the fractional Fe abundance is 0.5 +/- 0.1 of the solar photospheric value. Using these parameters a path length of about 8,000 km is derived. There is no evidence for opacity in the quiescent X-ray spectrum of the star.

Affiliated with

Also associated with

No associations

Rating

Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity 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 Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flare X-ray observations of AB Dor: evidence for Stellar Coronal Opacity will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-176752