期刊
ASTROPHYSICAL JOURNAL LETTERS
卷 878, 期 2, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.3847/2041-8213/ab263c
关键词
asteroseismology; stars: oscillations; stars: variables: general; white dwarfs
资金
- National Science Foundation [AST-1440341, AST-1514737, ACI-1663688]
- Caltech
- IPAC
- Weizmann Institute for Science
- Oskar Klein Center at Stockholm University
- University of Maryland
- University of Washington
- Deutsches Elektronen-Synchrotron
- Humboldt University
- Los Alamos National Laboratories
- TANGO Consortium of Taiwan
- University of Wisconsin at Milwaukee
- Lawrence Berkeley National Laboratories
- W.M. Keck Foundation
- KITP [PHY-1748958]
- Gordon and Betty Moore Foundation [GBMF5076]
Using high-cadence observations from the Zwicky Transient Facility at low Galactic latitudes, we have discovered a new class of pulsating, hot compact stars. We have found four candidates, exhibiting blue colors (g - r <= -0.1 mag), pulsation amplitudes of >5%, and pulsation periods of 200-475 s. Fourier transforms of the light curves show only one dominant frequency. Phase-resolved spectroscopy for three objects reveals significant radial velocity, T-eff, and log(g) variations over the pulsation cycle, which are consistent with large-amplitude radial oscillations. The mean T-eff and log (g) for these stars are consistent with hot subdwarf B (sdB) effective temperatures and surface gravities. We calculate evolutionary tracks using MESA and adiabatic pulsations using GYRE for low-mass, helium-core pre-white dwarfs (pre-WDs) and low-mass helium-burning stars. Comparison of low-order radial oscillation mode periods with the observed pulsation periods show better agreement with the pre-WD models. Therefore, we suggest that these new pulsators and blue large-amplitude pulsators (BLAPs) could be members of the same class of pulsators, composed of young approximate to 0.25-0.35 M-circle dot helium-core pre-WDs.
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