The nature of the high latitude B-type binary, SU Piscium.
Abstract
A spectroscopic orbit is presented for the early-type eclipsing binary star SU Psc and minimum masses of approximately 11 solar mass are deduced for both components. Photometric colors and intermediate dispersion spectra are used to deduce a composite spectral type for this system. The relative strengths of the hydrogen lines in the two components implies a magnitude difference of Delta B approximates to 1.0 and allows spectral types of B3III and B5III to be estimated for the primary and secondary stars, respectively. The SU Psc system would therefore appear to consist of a pair of normal young hydrogen burning B-type stars; their high galactic latitude (b approximates to 48 deg) would then imply that they are at a distance of more than 3 kpc from the galactic plane. Evolutionary ages of approximately 107 years for both components are smaller than the estimated time (approximates to 4 x 107 years) for the system to have been moved from the galactic disk to its current position. However given the uncertainties, these estimates are still consistent with SU Psc having been ejected from the galactic plane, possibly via dynamical interactions in a young open cluster.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1993
- Bibcode:
- 1993A&A...278...68D
- Keywords:
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- B Stars;
- Eclipsing Binary Stars;
- Stellar Spectrophotometry;
- Radial Velocity;
- Stellar Evolution;
- Stellar Orbits;
- Astronomy