The Eclipsing Binary System LB 3459
Abstract
Preliminary results of observations of the extremely blue foreground LMC star LB 3459, which has been found to be an eclipsing binary system, are reported. The spectroscopic observations were obtained on the South African Astronomical Observatory 1.9-m telescope, the Anglo-Australian 3.6-m telescope and the IUE satellite, and allow the derivation of the system orbital elements. Masses of the secondary and separations and radii of the two stars are calculated for a range of primary star masses using the mass function obtained. Spectra reveal the presence of the Balmer series, He II, Si IV, N IV, Si III/Fe V, Lyman alpha, N V, Si IV, and C IV lines, and indicate a primary temperature between 60,000 and 70,000 K. The primary star is thus concluded to be a very hot O-type subdwarf, while the secondary, which is about 3 magnitudes fainter than the primary, hot, but of rather large radius, remains unclassified. Observations also suggest that the system has undergone mass transfer twice, or some kind of common envelope phase.
- Publication:
-
IAU Colloq. 53: White Dwarfs and Variable Degenerate Stars
- Pub Date:
- 1979
- Bibcode:
- 1979wdvd.coll..255K
- Keywords:
-
- Eclipsing Binary Stars;
- Light Curve;
- O Stars;
- Stellar Spectra;
- Stellar Spectrophotometry;
- White Dwarf Stars;
- Iue;
- Stellar Mass Ejection;
- Ubv Spectra;
- Visible Spectrum;
- Astrophysics