Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs

Details Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs

1998-12-04

arxiv.org/abs/astro-ph/9812090v1

Astronomy and Astrophysics

Astrophysics

3 pages, 2 figures, Proceedings of `The Universe as seen by ISO' conference, Paris, Oct 1998

Scientific paper

We present ISOCAM 7 micron and 15 micron observations of 12 nearby white dwarfs, 6 of which have been found to have metals such as Ca, Mg and Fe in their photospheres. Our purpose was to search for an excess of infrared emission above the stellar photospheres. We find that none of the white dwarfs other than G29-38 shows a detectable infrared excess and this places strong constraints on the existence of a dusty disk around these stars. We conclude that ongoing accretion of the interstellar medium seems an unlikely explanation for the existence of metals in the photospheres of cool hydrogen atmosphere white dwarfs. The excess associated with G29-38 is 3.8+/-1.0 mJy and 2.9+/-0.6 mJy at 7 micron and 15 micron respectively. The broadband spectrum of this star strengthens the hypothesis that the infrared excess arises from a disk of particulate matter surrounding the white dwarf rather than from a cool brown dwarf companion.

Affiliated with

Also associated with

No associations

Rating

Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observational Constraints on the Origin of Metals in Cool DA-type White Dwarfs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-236074