JHK Photometry of WD 0950+139

Abstract

We present results from several nights of JHK photometry of the hot DA white dwarf 0950+139. It has a significant infrared excess over the expected flux from the white dwarf alone, confirming a previous finding by Zuckerman et al. (1991). The infrared excess corresponds to an upper limit on the spectral type of a companion of M4 V. We consider two models for the infrared excess of 0950+139, involving either a mid-M dwarf or a substellar object as a close companion. If 0950+139 is a close binary with a period of days, we predict that we should detect variation in the infrared fluxes due to reprocessing by the companion. Such variation was not detected, which may mean the system has a different orbital period or an inclination near 0 deg.