An extensive Delta a-photometric survey of southern B and A type bright stars

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

20

Techniques: Photometric, Stars: Chemically Peculiar, Catalogues

Scientific paper

Photoelectric photometry of 803 southern BS objects in the Delta a-system as detection tool for magnetic chemically peculiar (=CP2) stars has been carried out and compared to published spectral types. The statistical yield of such objects detected by both techniques is practically the same. We show that there are several factors which contaminate the search for these stars, but this contamination is only of the order of 10% in both techniques. We find a smooth transition from normal to peculiar stars. Our sample exhibits the largest fraction of CP2 stars at their bluest colour interval, i.e. 10% of all stars in the colour range -0.19 <= B-V < -0.10 or -0.10 <= b-y < -0.05. No peculiar stars based on the Delta a-criterion were found at bluer colours. Towards the red side the fraction of CP2 stars drops to about 3% for positive values of B-V or b-y with red limits roughly corresponding to normal stars of spectral type A5. The photometric behaviour of other peculiar stars: Am, HgMn, delta Del, lambda Boo, He abnormal stars, as well as Be/shell stars and supergiants shows some slight, but definite deviations from normal stars. Spectroscopic and visual binaries are not distinguished from normal stars in their Delta a behaviour. The results of this work justify larger statistical work (e.g. in open clusters) employing more time-saving photometric methods (CCD). \newpage Based on observations obtained at the European Southern Observatory, La Silla, Chile. This research has made use of the Simbad database, operated at CDS, Strasbourg, France. Table 2 is only available in electronic form via anonymous ftp 130.79.128.5 or http://cdsweb.u-strasbg.fr/Abstract.html

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

An extensive Delta a-photometric survey of southern B and A type bright stars 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 An extensive Delta a-photometric survey of southern B and A type bright stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An extensive Delta a-photometric survey of southern B and A type bright stars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1330328

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