Astronomy and Astrophysics – Astrophysics
Scientific paper
Dec 1996
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996a%26as..120..431b&link_type=abstract
Astronomy and Astrophysics Supplement, v.120, p.431-450
Astronomy and Astrophysics
Astrophysics
26
Line: Formation, Line: Profiles, Stars: Magnetic Fields, Stars: Pre-Main Sequence, Stars: Individual: Ab Aur, Stars: Emission Line, Be
Scientific paper
The observations of the MUSICOS 1992 campaign concerned three scientific programs, among which was the study of azimuthal structures in the wind and chromosphere of the pre-main sequence Herbig Ae star AB Aur. The He I 5876A line of AB Aur, which is formed in the expanding chromosphere of this star, most probably in the innermost parts of its wind, was continuously monitored at a spectral resolution of 30000 for about 4 days. The line was discovered to be variable in a spectacular way, the profile changing from pure emission to a composite profile including a deep absorption component in the course of a few hours. In this paper we present strong clues that suggest a rotational modulation of the line, with a period corresponding to the stars rotation period of 32hrs. We confirmed the covariation of several non-photospheric spectral lines, formed at very different radial distances of the star, which strengthens the idea that the variability is the signature of azimuthal structures in the wind of AB Aur, most probably due to magnetically confined streams or loops emanating from the stellar surface. We present the data collected during the MUSICOS 1992 campaign, but also a data set of the He I D3 line obtained with FOE at KPNO during the years 1991-1994 and a series of IUE spectra containing the Mg II h & k UV lines obtained one month prior to the campaign. A thorough discussion of the possible interpretations of the spectacular variations of the He I 5876A line is presented.
Baudrand Jacques
Boehm Timon
Butler John C.
Carter Brandon
Catala Claude
No associations
LandOfFree
Azimuthal structures in the wind and chromosphere of the Herbig AE star AB Aurigae. Results from the MUSICOS 1992 campaign. 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 Azimuthal structures in the wind and chromosphere of the Herbig AE star AB Aurigae. Results from the MUSICOS 1992 campaign., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Azimuthal structures in the wind and chromosphere of the Herbig AE star AB Aurigae. Results from the MUSICOS 1992 campaign. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-810463