Kepler and TESS Observations of PG 1159-035
Abstract

PG 1159-035 is the prototype of the PG 1159 hot (pre-)white dwarf pulsators. This important object was observed during the Kepler satellite K2 mission for 69 days in 59 s cadence mode and by the TESS satellite for 25 days in 20 s cadence mode. We present a detailed asteroseismic analysis of those data. We identify a total of 107 frequencies representing 32= 1 modes, 27 frequencies representing 12= 2 modes, and eight combination frequencies. The combination frequencies and the modes with very highkvalues represent new detections. The multiplet structure reveals an average splitting of 4.0 ± 0.4μHz for= 1 and 6.8 ± 0.2μHz for= 2, indicating a rotation period of 1.4 ± 0.1 days in the region of period formation. In the Fourier transform of the light curve, we find a significant peak at 8.904 ± 0.003μHz suggesting a surface rotation period of 1.299 ± 0.002 days. We also present evidence that the observed periods change on timescales shorter than those predicted by current evolutionary models. Our asteroseismic analysis finds an average period spacing for= 1 of 21.28 ± 0.02 s. The= 2 modes have a mean spacing of 12.97 ± 0.4 s. We performed a detailed asteroseismic more »

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10371563
Journal Name:
The Astrophysical Journal
Volume:
936
Issue:
2
Page Range or eLocation-ID:
Article No. 187
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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