The Drop during Less than 300 days of a Dusty White Dwarf's Infrared Luminosity

Abstract

We report Spitzer/IRAC photometry of WD J0959-0200, a white dwarf that displays excess infrared radiation from a disk, likely produced by a tidally disrupted planetesimal. We find that in 2010, the fluxes in both 3.6 $\mu$m and 4.5 $\mu$m decreased ~ 35% in less than 300 days. The drop in the infrared luminosity is likely due to an increase of the inner disk radius from one of two scenarios: (i) a recent planetesimal impact; (ii) instability in the circumstellar disk. The current situation is tantalizing; high sensitivity, high cadence infrared studies will be a new tool to study the interplay between a disk and its host white dwarf star.

ApJ Letters, accepted

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• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• A gaseous metal disk around a white dwarf
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• Evidence for an Anhydrous Carbonaceous Extrasolar Minor Planet
• The fates of Solar system analogues with one additional distant planet
• Magnetism, X-rays, and Accretion Rates in WD 1145+017 and other Polluted White Dwarf Systems
• Linking long-term planetary $N$-body simulations with periodic orbits: application to white dwarf pollution
• Shallow Ultraviolet Transits of WD 1145+017
• Survivability of radio-loud planetary cores orbiting white dwarfs
• The unstable fate of the planet orbiting the A-star in the HD 131399 triple stellar system