Light and Color Measures of Magnetic Stars.
Abstract
A program is under way to obtain photoelectric photometry on the UB V system of nearly all the known peculiar A-type stars, using the 16- and 36-inch reflectors on Kitt Peak. The purpose of the project is to locate these stars in a U-B, B-V diagram and to determine which ones are variable in light and color. It has been found that except for the silicon-rich stars, the peculiar A-type stars fall on the main-sequence line in the U-B, B-V plane and show about as much scatter as do normal A-type stars. The silicon-rich stars, however, show considerable ultraviolet and blue excesses; these cannot be attributed to interstellar reddening or intrinsic variability. Among 17 stars measured at least three times, about 60% seem to be variable in light, about 35% show a detectable variation in B-V color, and only about 10% show a detectable variation in U-B color. %.
- Publication:
-
The Astronomical Journal
- Pub Date:
- 1960
- DOI:
- 10.1086/108124
- Bibcode:
- 1960AJ.....65R.481A