论文标题
PG 1159-035的开普勒和苔丝观察
Kepler and TESS Observations of PG 1159-035
论文作者
论文摘要
PG 1159-035是DOV热矮人矮人脉动器的原型。在开普勒卫星K2任务中观察到69天，在59 s的节奏模式下，苔丝卫星在20 s的节奏模式下观察到25天。我们对这些数据进行了详细的呼吸震分析。我们总共确定了代表32 L = 1模式的107个频率，代表12 L = 2模式的27个频率和8个组合频率。 K值非常高的组合频率和模式代表了新的检测。多重结构显示L = 1的平均分裂为4.0 +/- 0.4 MUHz，L = 2的平均分裂为6.8 +/- 0.2 MUHz，表明旋转周期为1.4 +/- 0.1天，在周期形成区域中。在光曲线的傅立叶变换中，我们发现在8.904 +/- 0.003 muhz处的显着峰表明表面旋转周期为1.299 +/- 0.002天。我们还提供了证据表明，观察到的时期在时间尺度上的变化短于当前进化模型所预测的时期。我们的小型分析发现L = 1中的21.28 +/- 0.02 s的平均周期间距。 L = 2模式的平均间距为12.97 +/- 0.4 s。我们通过将观察到的时期与进化模型的周期进行了比较，进行了详细的小意态拟合。最佳拟合模型具有TEFF = 129600 +/- 11100 K，质量M*= 0.565 +/- 0.024 msun，log G = 7.41+0.38-0.54，在光谱测定的不确定性内。我们主张在当前模型中的未来改进，例如在HE燃烧阶段的过度拍摄上，因为最佳拟合模型不能预测PG〜1159-03中检测到的所有脉动的激发。
PG 1159-035 is the prototype of the DOV hot pre-white dwarf pulsators. It 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 l=1 modes, 27 frequencies representing 12 l=2 modes, and 8 combination frequencies. The combination frequencies and the modes with very high k values represent new detections. The multiplet structure reveals an average splitting of 4.0+/-0.4 muHz for l=1 and 6.8+/-0.2 muHz for l=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+/-0.003 muHz 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 l=1 of 21.28+/-0.02 s. The l=2 modes have a mean spacing of 12.97+/-0.4 s. We performed a detailed asteroseismic fit by comparing the observed periods with those of evolutionary models. The best fit model has Teff=129600+/- 11100 K, mass M*=0.565+/-0.024 Msun, and log g=7.41+0.38-0.54, within the uncertainties of the spectroscopic determinations. We argue for future improvements in the current models, e.g., on the overshooting in the He-burning stage, as the best-fit model does not predict excitation for all the pulsations detected in PG~1159-03.
