Show simple item record

dc.contributor.authorDay-Jones, Avril
dc.contributor.authorPinfield, D.J.
dc.contributor.authorRuiz, M.
dc.contributor.authorBeaumont, H.
dc.contributor.authorBurningham, B.
dc.contributor.authorGallardo, J.
dc.contributor.authorGianninas, A.
dc.contributor.authorBergeron, P.
dc.contributor.authorNapiwotzki, Ralf
dc.contributor.authorJenkins, J.S.
dc.contributor.authorZhang, Z.H.
dc.contributor.authorMurray, D.N.
dc.contributor.authorCatalan, Silvia
dc.contributor.authorInes Gomes, Joana
dc.date.accessioned2011-08-15T11:01:29Z
dc.date.available2011-08-15T11:01:29Z
dc.date.issued2011
dc.identifier.citationDay-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.issn0035-8711
dc.identifier.otherORCID: /0000-0003-4600-5627/work/64327321
dc.identifier.urihttp://hdl.handle.net/2299/6195
dc.descriptionThe definitive version is available at : www3.interscience.wiley.com Copyright Wiley-Blackwell and Royal Astronomical Society
dc.description.abstractWe 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.extent2196456
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.subjectbinaries : general
dc.subjectbrown dwarfs
dc.subjectwhite dwarfs
dc.titleDiscovery of a T dwarf + white dwarf binary systemen
dc.contributor.institutionSchool of Physics, Astronomy and Mathematics
dc.contributor.institutionScience & Technology Research Institute
dc.contributor.institutionCentre for Astrophysics Research
dc.description.statusPeer reviewed
rioxxterms.versionofrecord10.1111/j.1365-2966.2010.17469.x
rioxxterms.typeJournal Article/Review
herts.preservation.rarelyaccessedtrue


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record