Follow-up Observations of SPY White Dwarf + M-Dwarf Binaries

Abstract

We present the results of follow-up observations of white-dwarf + M-dwarf binaries identified using spectra obtained as part of the SPY survey. Spectra of the Halpha region were obtained with the SPIRAL spectrograph on the AAT telescope. Of the eleven stars observed, seven are binaries with periods in the range 2.8 hours to 7.7 days. We also show that one of our targets, WD 0137-349, has a brown dwarf companion.