| dc.identifier.citation | Littlefair , S P , Casewell , S L , Parsons , S G , Dhillon , V S , Marsh , T R , Gansicke , B T , Bloemen , S , Catalan , S , Irawati , P , Hardy , L K , Mcallister , M , Bours , M C P , Richichi , A , Burleigh , M R , Burningham , B , Breedt , E & Kerry , P 2014 , ' The substellar companion in the eclipsing white dwarf binary SDSS J141126.20+200911.1 ' , Monthly Notices of the Royal Astronomical Society , vol. 445 , no. 2 , pp. 2106-2115 . https://doi.org/10.1093/mnras/stu1895 | |
| dc.description.abstract | We present high time resolution SDSS-g′ and SDSS-z′ light curves of the primary eclipse in SDSS J141126.20+200911.1, together with time-resolved X-Shooter spectroscopy and near-infrared (NIR) JHKs photometry. Our observations confirm the substellar nature of the companion, making SDSS J141126.20+200911.1 the first eclipsing white dwarf/brown dwarf binary known. We measure a (white dwarf model dependent) mass and radius for the brown dwarf companion of M2 = 0.050 ± 0.002 M⊙ and R2 = 0.072 ± 0.004 M⊙, respectively. The lack of a robust detection of the companion light in the z′-band eclipse constrains the spectral type of the companion to be later than L5. Comparing the NIR photometry to the expected white dwarf flux reveals a clear Ks-band excess, suggesting a spectral type in the range L7–T1. The radius measurement is consistent with the predictions of evolutionary models, and suggests a system age in excess of 3 Gyr. The low companion mass is inconsistent with the inferred spectral type of L7–T1, instead predicting a spectral type nearer T5. This indicates that irradiation of the companion in SDSS J141126.20+200911.1 could be causing a significant temperature increase, at least on one hemisphere | en |
