A near-IR spectrum of the DO white dwarf RE J0503-285
  We present a near-IR spectroscopic analysis of the intriguing DO white dwarf RE J0503-285. The IR spectrum fails to reveal evidence of the presence of a spatially unresolved, cool, late-type companion. Hence we have placed an approximate limit on the spectral-type and mass of a putative companion (later than M8, M<0.085Msun). This result rules out ongoing interaction between the white dwarf and a close companion with M>0.085Msun as responsible for the discrepancies between the observed photospheric abundances and model predictions. As the possibility remains that there is a cooler companion lying beyond the detection threshold of this study we use our modelling to estimate the improvement in sensitivity offered by a Spitzer observation. 
Paul Dobbie (1), Matt Burleigh (1), Andrew Levan (1), Martin Barstow   (1), Ralf Napiwotzki (1) and Ivan Hubeny (2). ((1) Un...