First Photometric Solution of a Very Short Period Contact Binary Below the Period Limit
Abstract
The star 1SWASP J022727.03+115641.7 was reported as a contact binary with a period shorter than the empirical limit of such systems. Our study shows the star not to be variable. Instead, it is the nearby star, 2MASS 02272637+1156494, that exhibits variability. The BRI CCD light curves of 2MASS 02272637+1156494 show the system to be a moderate mass ratio (2.154-0.074+0.008), and shallow contact (10.4-1.9+1.4%) W-type contact binary. The masses, radii, and luminosities of the binary components are, respectively, {{M}1}=0.25-0.01+0.05 {{M}⊙ }, {{M}2}=0.54-0.04+0.11 {{M}⊙ }, {{R}1}=0.45-0.01+0.02 {{R}⊙ }, {{R}2}=0.63-0.02+0.04 {{R}⊙ }, {{L}1}=0.038-0.005+0.018 {{L}⊙ }, and {{L}2}=0.071-0.010+0.037 {{L}⊙ }, with an estimated distance 326-46+127 pc. These uncertainties mainly come from the errors of the colors used to estimate the temperature of the primary star. A dark spot was introduced on the massive component in the final solution.
- Publication:
-
The Astronomical Journal
- Pub Date:
- March 2015
- DOI:
- 10.1088/0004-6256/149/3/111
- Bibcode:
- 2015AJ....149..111L
- Keywords:
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- binaries: close;
- binaries: eclipsing;
- stars: evolution;
- stars: individual: 2MASS 02272637+1156494