Is the Oxygen-Rich White Dwarf SDSS J1242+5226 Accreting Water-Abundant Debris?

被引：0

作者：

Raddi, R. ^{[1
]}

Gaensicke, B. T. ^{[1
]}

Koester, D. ^{[2
]}

Farihi, J. ^{[3
]}

Hermes, J. J. ^{[1
]}

Scaringi, S. ^{[4
,5
]}

Breedt, E. ^{[1
]}

Girven, J. ^{[1
]}

机构：

[1] Univ Warwick, Dept Phys, Gibbet Hill Rd, Coventry CV4 7AL, W Midlands, England

[2] Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany

[3] UCL, Dept Phys & Astron, London WC1E 6BT, England

[4] Inst Astron, NL-3001 Leuven, Netherlands

[5] Max Planck Inst Astrophys, D-85748 Garching, Germany

来源：

19TH EUROPEAN WORKSHOP ON WHITE DWARFS | 2015年 / 493卷

关键词：

EXTRASOLAR MINOR PLANET; G29-38; DISKS;

D O I：

暂无

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We identified a new strongly metal polluted white dwarf, and report the determination of hydrogen and traces of O, Na, Mg, Si, Ca, Ti, Cr, and Fe in a helium dominated atmosphere. The four most common rock-forming elements, i.e. O, Mg, Si, and Fe embody almost entirely the 10(24) g of metals that are mixed in the convection zone. Oxygen is the most abundant of these four elements and we estimate that about 50-60% of it is in excess with respect to the amount expected from the accretion of mineral oxides. We suggest that the parent body that of the planetary debris detected in this white dwarf was composed by 28-48% water. We also note that a handful of other known debris-polluted white dwarfs, like GD 61, GD 16, and GD 362 may be the actively accreting examples of a larger number of stars that previously accreted water rich debris. We speculate that the hydrogen content of DBA and DZ white dwarfs could have a similar origin.

引用

页码：273 / 278

页数：6