The Variable Star S Doradus as an Eclipsing Binary.
Abstract
On the basis of 1120 photographic plates in the Harvard collection a light-curve of S Doradus has been derived. The light-curve can be interpreted as that of an eclipsing star with a period of 40.2 years. Four minima are observed: in 1890, 1900, 1930, and 1940; the system has the large eccentricity of 0.4. In addition to the four minima, secondary fluctuations appear in the light-curve. The eclipse lasts over 3 years. The maximum brightness of the star was 8~8, and the range for both minima was O~64. Calculations based on the light-curve, an adopted bolometric correction, and the known modulus of the Large Magellanic Cloud lead to masses of 60 and 55 0 and radii of 1400 and 1260 0. By the use of a method that has been found to be valid for normal eclipsing stars, radii of 2100 and 1900 0 are deduced, masses of 160 and 145 0, and absolute bolometric magnitudes of -12.7 and -12.5; but the stars are probably underluminous and may lie about 3 mag. below the extrapolated mass-luminosity relation. The spectrum shows the bright lines of hydrogen, which did not disappear during the minimum of 1930
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1943
- DOI:
- 10.1086/144509
- Bibcode:
- 1943ApJ....97..166G