How Sublimation Delays the Onset of Dusty Debris Disk Formation around White Dwarf Stars

Steckloff, Jordan K. and Debes, John and Steele, Amy and Johnson, Brandon and Adams, Elisabeth R. and Jacobson, Seth A. and Springmann, Alessondra (2021) How Sublimation Delays the Onset of Dusty Debris Disk Formation around White Dwarf Stars. The Astrophysical Journal Letters, 913 (2). L31. ISSN 2041-8205

[thumbnail of Steckloff_2021_ApJL_913_L31.pdf] Text
Steckloff_2021_ApJL_913_L31.pdf - Published Version

Download (1MB)

Abstract

Although numerous white dwarf stars host dusty debris disks, the temperature distribution of these stars differs significantly from the white dwarf population as a whole. Dusty debris disks exist exclusively around white dwarfs cooler than 27,000 K. This is all the more enigmatic given that the formation processes of dusty debris disks should favor younger, hotter white dwarfs, which likely host more dynamically unstable planetary systems. Here we apply a sophisticated material sublimation model to white dwarf systems to show that these statistics are actually a natural result of the interplay of thermal and tidal forces and how they define the circumstellar regions where dusty debris disks can form. We demonstrate that these processes tend to prevent stability against both sublimative destruction and reaccretion into planetesimals for rocky materials until white dwarfs cool to below ∼25,000–32,000 K, in agreement with the observed limit of ∼27,000 K. For pure water ice, this critical temperature is less than 2700 K (requiring a cooling age older the universe); this precludes pure water ice–rich debris disks forming through the accepted two-step mechanism. The critical temperature is size-dependent; more massive white dwarfs could potentially host dusty debris disks at warmer temperatures. Our model suggests that the location of the disks within the PG 0010+280, GD 56, GD 362, and PG 1541+651 systems are consistent with a forsterite-dominated olivine composition. We also find that very cool white dwarfs may simultaneously host multiple, independently formed dusty debris disks, consistent with observations of the LSPM J0207+3331 system.

Item Type: Article
Subjects: Middle East Library > Physics and Astronomy
Depositing User: Unnamed user with email support@middle-eastlibrary.com
Date Deposited: 11 May 2023 07:44
Last Modified: 20 Sep 2024 04:21
URI: http://editor.openaccessbook.com/id/eprint/768

Actions (login required)

View Item
View Item