A Debris Disk around the Central Star of the Helix Nebula?

Abstract

Excess emission from a point-like source coincident with the central star of the Helix Nebula is detected with Spitzer at 8, 24, and 70 um. At 24 um, the central source is superposed on an extended diffuse emission region. While the [OIV] 25.89 um line contributes to the diffuse emission, a 10-35 um spectrum of the central source shows a strong thermal continuum. The excess emission from the star most likely originates from a dust disk with blackbody temperatures of 90--130 K. Assuming a simple optically thin debris disk model, the dust is distributed in a ring between ~35 and ~150 AU from the central star, possibly arising from collisions of Kuiper-Belt-like Objects or the break-up of comets from an Oort-like cloud that have survived from the post-main-sequence evolution of the central star.

emulateapj format, accepted for publication in ApJ Letters

References in corpus (2)

• Carbon Deficiency in Externally-Polluted White Dwarfs: Evidence for Accretion of Asteroids
• Trigonometric Parallaxes of Central Stars of Planetary Nebulae

Cited by in corpus (6)

• An Unbiased Survey of 500 Nearby Stars for Debris Disks: A JCMT Legacy Program
• The Discovery of a Companion to the Lowest Mass White Dwarf
• Ground-based Optical and SPITZER Infrared Imaging Observations of Comet 21P/Giacobini-Zinner
• VLT / Infrared Integral Field Spectrometer Observations of Molecular Hydrogen Lines in the Knots in the Planetary Nebula NGC 7293 (the Helix Nebula)
• An occultation event in a triple post-AGB star
• The incidence of mid-infrared excesses in G and K giants