Ap stars with resolved magnetically split lines.
Abstract
New high-resolution spectroscopic observations of Ap stars with resolved magnetically split spectral lines are presented. Six new such stars have been discovered: HD 2453, HD 9996, HD 18078, HD 50169, HD 137949, and HD 192678. This raises the total number of known Ap stars with resolved magnetically split lines to 21. The spectral line profiles observed in two more stars, HD 111133 and HD 147010, are strongly affected by the magnetic field, but they are not fully resolved, due to non-negligible rotational Doppler effect. Observations of fairly sharp-lined Ap stars whose lines are unresolved are also presented. The relative difference between the equivalent widths of the Fe II lines λ6147.7 and λ6149.2 is shown to increase with the mean magnetic field modulus. The existence of a simple, unambiguous correlation between the mean magnetic field modulus and the index Z of Geneva photometry, which had previously been advocated, is not confirmed. At most, stars with large negative values of Z may be more prone to have strong magnetic fields, but the evidence for this is not statistically strong.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 1992
- Bibcode:
- 1992A&A...256..169M
- Keywords:
-
- A Stars;
- Line Shape;
- Peculiar Stars;
- Stellar Magnetic Fields;
- Stellar Spectra;
- Metallicity;
- Spectral Resolution;
- Stellar Spectrophotometry;
- Astrophysics