Examining Infrared Excesses of White Dwarfs (2016)
Undergraduates: Patrick O'Brien, Erik Dennihy Bart Dunlap
Faculty Advisor: Christopher Clemens
Department: Physics & Astronomy
To the surprise of many astronomers, recent surveys revealed a number of long-dead white dwarf stars that exhibit evidence for evolved planetary systems: circumstellar disks, the remnants of rocky planetesimals or asteroids torn apart by the immense gravity of the host star. As white dwarfs characterize the evolutionary endpoint of nearly every star in the Milky Way, this dusty disk configuration represents a potential future for our own Solar System. These systems are informative in the far infrared, where disks appear as excesses in the star¿¿¿s predicted flux. However, binary companions can also contribute infrared light so the near IR, accessible from ground-based observations, is a useful diagnostic for identifying disk systems.
Infrared data are a valuable complement to optical photometric and spectroscopic observations for investigating the composition and evolution of white dwarf planetary systems. This project explores the fundamentals of infrared astronomy to determine challenges that face discovery and analysis of substellar flux sources. I will be studying the function of the SPARTAN near IR camera as well as optimizing procedures for observing remotely at UNC. This project will employ reduction of IR data to improve calibration techniques and determine the need for follow-up studies. I will then develop an infrared data reduction pipeline to efficiently analyze subsequent observations. These methods will support extensive study of a dusty white dwarf candidate.