Astronomy and Astrophysics – Astrophysics
Scientific paper
Jan 2012
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012astbu..67...57z&link_type=abstract
Astrophysical Bulletin, Volume 67, Issue 1, pp.57-66
Astronomy and Astrophysics
Astrophysics
Stars: Chemically Peculiar, Stars: Individual: Hd 90569
Scientific paper
Axial rotation of a star plays an important role in its evolution, physical condition in its atmosphere and appearance of its spectrum. Methods of determinations of υ sin i are based on comparison of the observed profiles of spectral lines with theoretical ones. Their accuracy depends on the kind and quality of spectrograms as well as on the algorithms used. A frequently used method is the simple comparing of one line, e.g. the Ca II at 3933 Å or Mg ii at 4481 Å. This however, may result in a false value of υ sin i if low dispersion spectra are used. In this work we studied contemporary CCD as well as older photographic spectra of the multiple star HD90569. We determined the projected rotational velocity value to be υ sin i = 11 km/s. Besides formerly reported enhancing of lines of Cr, Fe, Mn and Sr, we found also large overabundances of rare earths, gallium and platinum. Helium, carbon, nitrogen, oxygen, aluminium, calcium, scandium and nickel are in deficit. The spectrum of the occultation double was not identified to be of the SB2-type, however, there are some observable evidences that the pair creates a binary with a long orbital period. Despite this there are also observations that leave such interpretation uncertain.
Barzova I.
Iliev Ilian
Kudryavtsev Dmitry
Romanyuk Iosif I.
Semenko E.
No associations
LandOfFree
Stars with discrepant υ sin i as derived from Ca II 3933 and Mg II 4481 Å lines. II. Multiple star HD 90569 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 Stars with discrepant υ sin i as derived from Ca II 3933 and Mg II 4481 Å lines. II. Multiple star HD 90569, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stars with discrepant υ sin i as derived from Ca II 3933 and Mg II 4481 Å lines. II. Multiple star HD 90569 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-908093