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.
Original language | English |
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Pages (from-to) | 3218-3226 |
Number of pages | 9 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 447 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1 Jan 2015 |
Keywords
- Binaries: close
- Brown dwarfs
- White dwarfs