Another one grinds the dust: variability of the planetary debris disc at the white dwarf SDSS J104341.53+085558.2

Manser, Christopher J.; Gänsicke, Boris T.; Koester, Detlev; Marsh, Thomas R.; Southworth, John

Abstract

We report 9 yr of optical spectroscopy of the metal-polluted white dwarf SDSS J104341.53+085558.2, which presents morphological variations of the line profiles of the 8600 Å Ca?II triplet emission from the gaseous component of its debris disc. Similar changes in the shape of the Ca?II triplet have also been observed in two other systems that host a gaseous disc, and are likely related to the same mechanism. We report the Mg, Si, and Ca abundances of the debris detected in the photosphere of SDSS J1043+0855, place upper limits on O and Fe, and derive an accretion rate of (2.5–12)?×?108 g s-1, consistent with those found in other systems with detected debris discs. The Mg/Si ratio and the upper limit on the Fe/Si ratio of the accreted material broadly agree with those found for the crust of the Earth. We also review the range of variability observed among white dwarfs with planetary debris discs.

• Journal Article Type: Article
• Acceptance Date: Jul 18, 2016
• Online Publication Date: Jul 20, 2016
• Publication Date: Oct 21, 2016
• Publicly Available Date: May 26, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 462
• Issue: 2
• Pages: 1461 - 1469
• DOI: https://doi.org/10.1093/mnras/stw1760
• Keywords: accretion, accretion discs, circumstellar matter, line, profiles, stars, individual, SDSS J104341.53+085558.2230, white dwarfs
• Publisher URL: http://dx.doi.org/10.1093/mnras/stw1760