A J-band detection of the sub-stellar mass donor in SDSS J1433+1011

作者：Littlefair S P^*; Savoury C D J; Dhillon V S; Marsh T R; Gaensicke B T; Butterleym T; Wilson R W; Southworth J; Watson C A

来源：Monthly Notices of the Royal Astronomical Society, 2013, 431(3): 2820-2825.

DOI：10.1093/mnras/stt378

• binaries: eclipsing
• stars: dwarf novae
• stars: individual: SDSS J1433+1011
• novae, cataclysmic variables

We present time-resolved J-band spectroscopy of the short-period cataclysmic variable SDSS J143317.78+101123.3. We detect absorption lines from the sub-stellar donor star in this system, which contributes 38 +/- 5 per cent to the J-band light. From the relative strengths of the absorption lines in the J band, we estimate the spectral type of the donor star to be L2 +/- 1. These data are the first spectroscopic detection of a donor with a confirmed sub-stellar mass in a cataclysmic variable, and the spectral type is consistent with that expected from semi-empirical evolutionary models. %26lt;br%26gt;Using skew mapping, we have been able to derive an estimate for the radial velocity of the donor of K-d = 520 +/- 60 km s(-1). This value is consistent with, though much less precise than, predictions from mass determinations found via photometric fitting of the eclipse light curves.

• 出版日期2013-5