Program: GN-2012B-Q-60

We propose to study an intriguing system at the core of planetary nebula EGB 6, which is a promising example of the planetary impact phenomenon. The complex EGB 6 nucleus consists of (1) a hot (~100,000 K) white dwarf (WD), (2) a peculiar over-luminous 2,000 K companion 116 AU (0.18'') from the WD, (3) a very dense gaseous disk around this companion, and (4) a ~185--450 K dust cloud/disk, with exact location unknown. A planet-planet or planet-brown dwarf merger may explain the overluminous nature of the companion and its surrounding accretion disk. Collisions of subplanetary objects around the WD, enhanced by the gravitational influence of planet merger, could account for the observed dust disk. We request 1.75 hours for GNIRS+Altair-LGS observations of EGB 6, in order to (1) extract spatially-resolved spectrum of the WD's companion to study its physical properties and (2) to pinpoint the location of dust in this system. If the overluminous companion was indeed formed through a merger event, the detection of such an impact-induced super luminous example would represent an important milestone in establishing the existence of giant impacts observationally.