Direct Detection of the L-Dwarf Donor in WZ Sagittae
Abstract
Analysis of a large set of phase-resolved K-band spectra of the cataclysmic variable WZ Sge shows that the secondary star of this system appears to be an L-dwarf. Previous K-band spectra of WZ Sge found that the CO overtone bandheads were in emission. We show that absorption from the 12CO(2,0) bandhead of the donor star creates a dip in the 12CO(2,0) emission feature. Measuring the motion of this feature over the orbital period, we construct a radial velocity curve that gives a velocity amplitude of Kabs = 520 ± 35 km s-1, consistent with the previously published values for this parameter.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 2016
- DOI:
- arXiv:
- arXiv:1511.07258
- Bibcode:
- 2016ApJ...816....4H
- Keywords:
-
- brown dwarfs;
- novae;
- cataclysmic variables;
- stars: dwarf novae;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 16 pages, 7 figures. Accepted for publication in the Astrophysical Journal