In 1974 Shore and Adelman suggested that the magnetic chemically peculiar star 56 Arietis (= HD 19832) might be undergoing a free body precession both on theoretical grounds and from a comparison of spectroscopic data obtained at different epochs. In 1993 we published UBV and uvby photometry obtained at the Braesdie Observatory and the Four College Automated Photoelectric Telescope, respectively, which was significantly different from published values. We found that observations with each filter taken in the fall of 1990 showed small differences in the shapes of the light curves compared with similar observations in the fall of 1991. Now we have observations for two additional years and are obtaining data during the current observing season. In addition to 56 Ari, several other magnetic CP stars such as 108 Aqr have been found to have changes in the shapes of their light curves relative to published photometry. This suggests that many magnetic CP stars might also be precessing. Those magnetic CP stars which are photometric variables and whose light curves are the same as published values need to be observed several times as there is always the possibility that they might have been observed at the same orbital phase.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1994