dc.contributor.author | Day-Jones, Avril | |
dc.contributor.author | Pinfield, D.J. | |
dc.contributor.author | Ruiz, M. | |
dc.contributor.author | Beaumont, H. | |
dc.contributor.author | Burningham, B. | |
dc.contributor.author | Gallardo, J. | |
dc.contributor.author | Gianninas, A. | |
dc.contributor.author | Bergeron, P. | |
dc.contributor.author | Napiwotzki, Ralf | |
dc.contributor.author | Jenkins, J.S. | |
dc.contributor.author | Zhang, Z.H. | |
dc.contributor.author | Murray, D.N. | |
dc.contributor.author | Catalan, Silvia | |
dc.contributor.author | Ines Gomes, Joana | |
dc.date.accessioned | 2011-08-15T11:01:29Z | |
dc.date.available | 2011-08-15T11:01:29Z | |
dc.date.issued | 2011 | |
dc.identifier.citation | Day-Jones , A , Pinfield , D J , Ruiz , M , Beaumont , H , Burningham , B , Gallardo , J , Gianninas , A , Bergeron , P , Napiwotzki , R , Jenkins , J S , Zhang , Z H , Murray , D N , Catalan , S & Ines Gomes , J 2011 , ' Discovery of a T dwarf + white dwarf binary system ' , Monthly Notices of the Royal Astronomical Society , vol. 410 , no. 2 , pp. 705-716 . https://doi.org/10.1111/j.1365-2966.2010.17469.x | |
dc.identifier.issn | 0035-8711 | |
dc.identifier.other | ORCID: /0000-0003-4600-5627/work/64327321 | |
dc.identifier.uri | http://hdl.handle.net/2299/6195 | |
dc.description | The definitive version is available at : www3.interscience.wiley.com Copyright Wiley-Blackwell and Royal Astronomical Society | |
dc.description.abstract | We present the discovery of the first T dwarf + white dwarf binary system LSPM 1459+0857 AB, confirmed through common proper motion and spectroscopy. The white dwarf is a high proper motion object from the LSPM catalogue that we confirm spectroscopically to be a relatively cool (Teff= 5535 ± 45 K) and magnetic (B∼ 2 MG) hydrogen-rich white dwarf, with an age of at least 4.8 Gyr. The T dwarf is a recent discovery from the UKIRT Infrared Deep Sky Survey (ULAS 1459+0857) and has a spectral type of T4.5 ± 0.5 and a distance in the range 43–69 pc. With an age constraint (inferred from the white dwarf) of >4.8 Gyr, we estimate Teff= 1200–1500 K and log g= 5.4–5.5 for ULAS 1459+0857, making it a benchmark T dwarf with well-constrained surface gravity. We also compare the T dwarf spectra with the latest LYON group atmospheric model predictions, which, despite some shortcomings, are in general agreement with the observed properties of ULAS 1459+0857. The separation of the binary components (16 500–26 500 au or 365 arcsec on the sky) is consistent with an evolved version of the more common brown dwarf + main-sequence (MS) binary systems now known, and although the system has a wide separation, it is shown to be statistically robust as a non-spurious association. The observed colours of the T dwarf show that it is relatively bright in the z band compared to other T dwarfs of similar type, and further investigation is warranted to explore the possibility that this could be a more generic indicator of older T dwarfs. Future observations of this binary system will provide even stronger constraints on the T dwarf properties, and additional systems will combine to give a more comprehensively robust test of the model atmospheres in this temperature regime. | en |
dc.format.extent | 2196456 | |
dc.language.iso | eng | |
dc.relation.ispartof | Monthly Notices of the Royal Astronomical Society | |
dc.subject | binaries : general | |
dc.subject | brown dwarfs | |
dc.subject | white dwarfs | |
dc.title | Discovery of a T dwarf + white dwarf binary system | en |
dc.contributor.institution | School of Physics, Astronomy and Mathematics | |
dc.contributor.institution | Science & Technology Research Institute | |
dc.contributor.institution | Centre for Astrophysics Research | |
dc.description.status | Peer reviewed | |
rioxxterms.versionofrecord | 10.1111/j.1365-2966.2010.17469.x | |
rioxxterms.type | Journal Article/Review | |
herts.preservation.rarelyaccessed | true | |