We report the discovery of a subtle infrared excess associated with the young white dwarf EC\,05365--4749 at 3.35 and 4.6\,μm. Follow-up spectroscopic observations are consistent with a hydrogen atmosphere white dwarf of effective temperature 22\,800\,K and log [\emph{g} (\,cm\,s−2) ] = 8.19. High resolution spectroscopy reveals atmospheric metal pollution with logarithmic abundances of [Mg/H] = --5.36 and [Ca/H] = --5.75, confirming the white dwarf is actively accreting from a metal-rich source with an intriguing abundance pattern. We find that the infrared excess is well modeled by a flat, opaque debris disk, though disk parameters are not well constrained by the small number of infrared excess points. We further demonstrate that relaxing the assumption of a circular dusty debris disk to include elliptical disks expands the widths of acceptable disks, adding an alternative interpretation to the subtle infrared excesses commonly observed around young white dwarfs.
@article{arxiv.1608.04384,
title = {A subtle IR excess associated with a young White Dwarf in the Edinburgh-Cape Blue Object Survey},
author = {E. Dennihy and John H. Debes and B. H. Dunlap and P. Dufour and Johanna K. Teske and J. C. Clemens},
journal= {arXiv preprint arXiv:1608.04384},
year = {2016}
}