SiO rotation-vibration bands in cool giants. I. A grid of model spectra for different stellar parameters.

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24

Stars: Atmospheres, Stars: Fundamental Parameters, Stars: Late-Type, Stars: Agb And Post-Agb, Infrared: Stars

Scientific paper

In order to study the behavior of the SiO bands of cool oxygen-rich stars we have computed a grid of 138 hydrostatic model atmospheres using an improved version of the MARCS code and new SiO line data. We found that the corresponding opacity never produces large changes of the atmospheric structure, especially if one compares it with the enormous effects from TiO or water. Based on the atmospheres, synthetic SiO spectra have been calculated with a high resolution for the photometric L-band and with a low resolution (opacity sampling) for the large wavelength range between 2.0 and 12.5μm, which includes the fundamental as well as the first and second overtone transitions. Thus, we could study the behavior of the SiO bands as a function of different stellar parameters. It turned out that the intensity of the absorption features monotonously increases with lower temperature and gravitational acceleration as well as with higher metallicity. We expect the strongest bands in the coolest and most extended objects. When we compared our results to observations of K and M giants, we found a good agreement showing the correctness of the line data and atmospheres. On the other hand the calculations can not reproduce the relatively weak and variable bands of AGB stars indicating that our classical model atmospheres may not always work for this kind of objects. This will be discussed in a second paper, where we will focus on our observations of AGB stars.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

SiO rotation-vibration bands in cool giants. I. A grid of model spectra for different stellar parameters. 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 SiO rotation-vibration bands in cool giants. I. A grid of model spectra for different stellar parameters., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and SiO rotation-vibration bands in cool giants. I. A grid of model spectra for different stellar parameters. will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1183714

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.