Multiwaveband photometry of the irradiated brown dwarf WD0137-349B

Casewell, S.L.; Lawrie, K.A.; Maxted, P.F.L.; Marley, M.S.; Fortney, J.J.; Rimmer, P.B.; Littlefair, S.P.; Wynn, G.; Burleigh, M.R.; Helling, Ch.

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 H+3 being generated in the atmosphere by the UV irradiation.

Citation

Casewell, S., Lawrie, K., Maxted, P., Marley, M., Fortney, J., Rimmer, P., Littlefair, S., Wynn, G., Burleigh, M., & Helling, C. (2015). Multiwaveband photometry of the irradiated brown dwarf WD0137-349B. Monthly Notices of the Royal Astronomical Society, 447(4), 3218 -3226. https://doi.org/10.1093/mnras/stu2721

• Journal Article Type: Article
• Acceptance Date: Dec 18, 2014
• Online Publication Date: Jan 15, 2015
• Publication Date: Mar 11, 2015
• Publicly Available Date: May 26, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 447
• Issue: 4
• Pages: 3218 -3226
• DOI: https://doi.org/10.1093/mnras/stu2721
• Keywords: stars, close binaries, brown dwarfs, white dwarfs
• Public URL: https://keele-repository.worktribe.com/output/404089
• Publisher URL: http://dx.doi.org/10.1093/mnras/stu2721