Multiwaveband photometry of the irradiated brown dwarf WD0137-349B
Abstract
WD0137-349 is a white dwarf-brown dwarf binary system in a 116 min orbit. We present radial velocity observations and multiwaveband photometry from V, R and I in the optical, to J, H and Ks in the near-IR and [3.6], [4.5], [5.8] and [8.0] μm in the mid-IR. The photometry and light curves show variability in all wavebands, with the amplitude peaking at [4.5] μm, where the system is also brightest. Fluxes and brightness temperatures were computed for the heated and unheated atmosphere of the brown dwarf (WD0137-349B) using synthetic spectra of the white dwarf using model atmosphere simulations. We show that the flux from the brown dwarf dayside is brighter than expected in the Ks and [4.5] μm bands when compared to models of irradiated brown dwarfs with full energy circulation and suggest this overluminosity may be attributed to H2 fluorescence or H3+ being generated in the atmosphere by the UV irradiation.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 2015
- DOI:
- 10.1093/mnras/stu2721
- arXiv:
- arXiv:1412.6363
- Bibcode:
- 2015MNRAS.447.3218C
- Keywords:
-
- binaries: close;
- brown dwarfs;
- white dwarfs;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 9 pages, 9 figures, 5 tables. Accepted for publication in MNRAS