WIRED for EC: New White Dwarfs with $\textit{WISE}$ Infrared Excesses and New Classification Schemes from the Edinburgh-Cape Blue Object Survey

TL;DR

This paper introduces a simple infrared excess detection method for white dwarf systems, successfully identifying new dusty debris disk candidates and providing insights into their evolution and classification.

Contribution

The study presents a novel single-temperature blackbody fitting technique for identifying dusty debris disks around white dwarfs, validated with known systems and applied to new candidates.

Findings

Identified four new dusty debris disk candidates.

Recovered three of four known Spitzer-confirmed disks.

Showed gaseous debris hosts lie along a boundary in the diagnostic plot.

Abstract

We present a simple method for identifying candidate white dwarf systems with dusty exoplanetary debris based on a single temperature blackbody model fit to the infrared excess. We apply this technique to a sample of Southern Hemisphere white dwarfs from the recently completed Edinburgh-Cape Blue Object Survey and identify four new promising dusty debris disk candidates. We demonstrate the efficacy of our selection method by recovering three of the four $\textit{Spitzer}$ confirmed dusty debris disk systems in our sample. Further investigation using archival high resolution imaging shows $\textit{Spitzer}$ data of the un-recovered fourth object is likely contaminated by a line-of-sight object that either led to a mis-classification as a dusty disk in the literature or is confounding our method. Finally, in our diagnostic plot we show that dusty white dwarfs which also host gaseous debris lie along a boundary of our dusty debris disk region, providing clues to the origin and evolution of these especially interesting systems.