The Library
Alkali metals in white dwarf atmospheres as tracers of ancient planetary crusts
Tools
Tools
Tools
Hollands, Mark A., Tremblay, Pier-Emmanuel, Gänsicke, Boris T., Koester, Detlev and Gentile-Fusillo, Nicola Pietro (2021) Alkali metals in white dwarf atmospheres as tracers of ancient planetary crusts. Nature Astronomy, 5 (5). pp. 451-459. doi:10.1038/s41550-020-01296-7
An open access version can be found in:
Official URL: https://doi.org/10.1038/s41550-020-01296-7
Abstract
White dwarfs that accrete the debris of tidally disrupted asteroids1 provide the opportunity to measure the bulk composition of the building blocks, or fragments, of exoplanets2. This technique has established a diversity of compositions comparable to what is observed in the Solar System3, suggesting that the formation of rocky planets is a generic process4. The relative abundances of lithophile and siderophile elements within the planetary debris can be used to investigate whether exoplanets undergo differentiation5, yet the composition studies carried out so far lack unambiguous tracers of planetary crusts6. Here we report the detection of lithium in the atmospheres of four cool (<5,000 K) and old (cooling ages of 5–10 Gyr ago) metal-polluted white dwarfs, of which one also displays photospheric potassium. The relative abundances of these two elements with respect to sodium and calcium strongly suggest that all four white dwarfs have accreted fragments of planetary crusts. We detect an infrared excess in one of the systems, indicating that accretion from a circumstellar debris disk is ongoing. The main-sequence progenitor mass of this star was 4.8 ± 0.2 M⊙, demonstrating that rocky, differentiated planets may form around short-lived B-type stars.
| Item Type: | Journal Item | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Divisions: | Faculty of Science, Engineering and Medicine > Science > Physics | ||||||||
| SWORD Depositor: | Library Publications Router | ||||||||
| Journal or Publication Title: | Nature Astronomy | ||||||||
| Publisher: | Springer | ||||||||
| ISSN: | 2397-3366 | ||||||||
| Official Date: | May 2021 | ||||||||
| Dates: |
|
||||||||
| Volume: | 5 | ||||||||
| Number: | 5 | ||||||||
| Page Range: | pp. 451-459 | ||||||||
| DOI: | 10.1038/s41550-020-01296-7 | ||||||||
| Status: | Not Peer Reviewed | ||||||||
| Publication Status: | Published | ||||||||
| Access rights to Published version: | Restricted or Subscription Access | ||||||||
| Open Access Version: |
Request changes or add full text files to a record
Repository staff actions (login required)
 |
View Item |
