ECHOES OF A DECAYING PLANETARY SYSTEM: THE GASEOUS AND DUSTY DISKS SURROUNDING THREE WHITE DWARFS
- Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States)
- CFHT Corporation, 65-1238 Mamalahoa Highway, Kamuela, HI 96743 (United States)
We have performed a comprehensive ground-based observational program aimed at characterizing the circumstellar material orbiting three single white dwarf stars previously known to possess gaseous disks. Near-infrared imaging unambiguously detects excess infrared emission toward Ton 345 and allows us to refine models for the circumstellar dust around two of the three white dwarf stars. We find that each white dwarf hosts gaseous and dusty disks that are roughly spatially coincident, a result that is consistent with a scenario in which dusty and gaseous material has its origin in remnant parent bodies of the white dwarfs' planetary systems. We briefly describe a new model for the gas disk heating mechanism in which the gaseous material behaves like a 'Z II' region. In this Z II region, gas primarily composed of metals is photoionized by ultraviolet light and cools through optically thick allowed Ca II-line emission.
- OSTI ID:
- 21464636
- Journal Information:
- Astrophysical Journal, Vol. 722, Issue 2; Other Information: DOI: 10.1088/0004-637X/722/2/1078; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
GASEOUS MATERIAL ORBITING THE POLLUTED, DUSTY WHITE DWARF HE 1349-2305
DUSTY DISKS AROUND WHITE DWARFS. I. ORIGIN OF DEBRIS DISKS