Parsons, S.G., Marsh, T.R., Gänsicke, B.T. et al. (8 more authors) (2012) The shortest period detached white dwarf + main-sequence binary. Monthly Notices of the Royal Astronomical Society, 419. pp. 304-313. ISSN 0035-8711
Abstract
We present high-speed ULTRACAM and SOFI photometry and X-shooter spectroscopy of the recently discovered 94-min orbital period eclipsing white dwarf/main-sequence binary SDSS J085746.18+034255.3 (CSS 03170) and use these observations to measure the system parameters. We detect a shallow secondary eclipse and hence are able to determine an orbital inclination of i = 85. ◦5 ± 0. ◦2. The white dwarf has a mass of 0.51 ± 0.05 M and a radius of 0.0247 ± 0.0008 R. With a temperature of 35 300 ± 400 K the white dwarf is highly overinflated if it has a carbon–oxygen core; however, if it has a helium core then its mass and radius are consistent with evolutionary models. Therefore, the white dwarf in SDSS J085746.18+034255.3 is most likely a helium core white dwarf with a mass close to the upper limit expected from evolution. The main-sequence star is an M8 dwarf with a mass of 0.09 ± 0.01 M and a radius of 0.110 ± 0.004 R placing it close to the hydrogen burning limit. The system emerged from a common envelope ∼20 million years ago and will reach a semidetached configuration in ∼400 million years, becoming a cataclysmic variable with a period of 66 min, below the period minimum. Ke
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2011The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
Keywords: | binaries: eclipsing; stars: fundamental parameters; stars: individual: CSS 03170; stars: low-mass; white dwarfs. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > Department of Physics and Astronomy (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 13 Jan 2017 12:27 |
Last Modified: | 13 Jan 2017 12:27 |
Published Version: | https://doi.org/10.1111/j.1365-2966.2011.19691.x |
Status: | Published |
Publisher: | Oxford University Press (OUP) |
Refereed: | Yes |
Identification Number: | 10.1111/j.1365-2966.2011.19691.x |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:109565 |