Collisions in a gas-rich white dwarf planetary debris disc.

Authors :: Swan A
Kenyon SJ
Farihi J
Dennihy E
Gänsicke BT
Hermes JJ
Melis C
von Hippel T
Source :: Monthly notices of the Royal Astronomical Society [Mon Not R Astron Soc] 2021 Jun 21; Vol. 506 (1), pp. 432-440. Date of Electronic Publication: 2021 Jun 21 (Print Publication: 2021).
Publication Year :: 2021
Abstract: WD 0145+234 is a white dwarf that is accreting metals from a circumstellar disc of planetary material. It has exhibited a substantial and sustained increase in 3-5 [Formula: see text]m flux since 2018. Follow-up Spitzer photometry reveals that emission from the disc had begun to decrease by late 2019. Stochastic brightening events superimposed on the decline in brightness suggest the liberation of dust during collisional evolution of the circumstellar solids. A simple model is used to show that the observations are indeed consistent with ongoing collisions. Rare emission lines from circumstellar gas have been detected at this system, supporting the emerging picture of white dwarf debris discs as sites of collisional gas and dust production.<br /> (© 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.)