期刊
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
卷 489, 期 2, 页码 1489-1508出版社
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stz1618
关键词
stars: individual: LP 40-365; subdwarfs; supernovae: general; white dwarfs; Galaxy: kinematics and dynamics
资金
- German Science Foundation (DFG) [HE1356/71-1, IR190/1-1]
- NASA - Space Telescope Science Institute [HST-HF2-51357.001-A]
- NASA [NAS5-26555, NAS 5-26555]
- DFG [GE 2056-12-1]
- Packard Foundation
- European Research Council under the European Union's Horizon 2020 research and innovation programme [677706 (WD3D)]
- European Union's Seventh Framework Programme (FP/20072013)/ERC [320964]
- UK STFC grant [ST/P000495]
- Alfred P. Sloan Foundation
- U.S. Department of Energy Office of Science
- Center for High Performance Computing at the University of Utah
- [15431]
- [093.D-0431]
- [097.D-1029]
- [0101.C-0646]
- [W/2017A/25]
- [W/2017A/30]
- [SW2017a12]
- STFC [ST/P000495/1] Funding Source: UKRI
We report the discovery of three stars that, along with the prototype LP 40-365, form a distinct class of chemically peculiar runaway stars that are the survivors of thermonuclear explosions. Spectroscopy of the four confirmed LP 40-365 stars finds ONe-dominated atmospheres enriched with remarkably similar amounts of nuclear ashes of partial O- and Si-burning. Kinematic evidence is consistent with ejection from a binary supernova progenitor; at least two stars have rest-frame velocities indicating they are unbound to the Galaxy. With masses and radii ranging between 0.20 and 0.28M(circle dot) and between 0.16 and 0.60 R-circle dot, respectively, we speculate these inflated white dwarfs are the partly burnt remnants of either peculiar Type Iax or electron-capture supernovae. Adopting supernova rates from the literature, we estimate that similar to 20 LP 40-365 stars brighter than 19 mag should be detectable within 2 kpc from the Sun at the end of the Gaia mission. We suggest that as they cool, these stars will evolve in their spectroscopic appearance, and eventually become peculiar O-rich white dwarfs. Finally, we stress that the discovery of new LP 40-365 stars will be useful to further constrain their evolution, supplying key boundary conditions to the modelling of explosion mechanisms, supernova rates, and nucleosynthetic yields of peculiar thermonuclear explosions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据