Computer Science
Scientific paper
May 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005phdt.........2v&link_type=abstract
PhD Thesis, Leuven: K.U.Leuven, 2005, 184 pages
Computer Science
14
Spectroscopy, Interferometry, Infrared, Giants, Supergiants, Oh/Ir
Scientific paper
In this thesis, we combine infrared spectroscopic and interferometric observations to study the atmospheres and dusty stellar winds of evolved (RGB, AGB and RSG) giant and super giant stars. We focus on (1) the exact mechanism driving the mass loss, e.g. the dust condensation sequence, and (2) the origin of the asymmetries seen later on in Planetary Nebulae. Extensive data sets are presented for the giant Arcturus, the supergiant Betelgeuse and the OH/IR star OH26.5+0.6. While the spectroscopic data on Arcturus can be well modelled using a single MARCS model atmosphere, the interferometric data suggest emission far out from the photosphere. We suggest this to be a subgiant companion at small (projected) separation. In Betelgeuse we find strong evidence for a thin layer of alumina dust grains only 0.5 stellar radii above the photosphere. This is the first time the dust condensation sequence is spatially resolved and confirms the crucial role of alumina. OH26.5+0.6 is found to have an asymmetric superwind, indicating that deviations from spherical symmetry already occur in the AGB phase. Moreover, the observed angular size throughout the N-band is not compatible with a spherical outflow model. Lastly, as a more practical contribution to the field of IR interferometry, we present a new network of mid-IR interferometric calibrators with new optical and near-IR photometry and accurate diameter estimates.
No associations
LandOfFree
Evolved stars: a combined view vrom interferometry and spectroscopy 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 Evolved stars: a combined view vrom interferometry and spectroscopy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Evolved stars: a combined view vrom interferometry and spectroscopy will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1378424