Signatures of Magnetic Activity in the Seismic Data of Solar-type Stars Observed by Kepler
Signatures of Magnetic Activity in the Seismic Data of Solar-type Stars Observed by Kepler
复制标题
开普勒观测到的太阳型恒星地震数据中的磁活动特征
DOI：
10.3847/1538-4365/aac9b6
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
R. Howe
中科院分区：
文献类型：
--
作者：
A. R. G. Santos;T. Campante;T. Campante;W. Chaplin;W. Chaplin;Margarida S. Cunha;M. Lund;M. Lund;R. Kiefer;D. Salabert;D. Salabert;R. A. García;R. A. García;G. R. Davies;G. R. Davies;Y. Elsworth;Y. Elsworth;R. Howe;R. Howe
在太阳中，可以观察到声波模式的频率随磁场活动水平的变化而变化。预计这些频率变化在太阳型恒星中是常见的，并且包含了在它们内部发生的与活动相关的变化的信息。开普勒光度时间序列前所未有的持续时间为通过星震学探测和表征恒星磁周期提供了独特的机会。在这项工作中，我们分析了87颗太阳型恒星的样本，测量了它们在90天内的时间频率变化。对于每个片段，通过贝叶斯峰值bagging工具获得单个频率。然后计算平均频移并与：(1)互相关法得到的频移进行比较；(2)模态高度的变化；(3)光度活度代理；(4)造粒的特征时间尺度。对于每颗恒星和90天的子序列，我们提供了平均频移、模态高度和颗粒化的特征时间尺度。有趣的是，超过60%的恒星在频移中显示出（准）周期性变化的证据。在大多数情况下，这些变化伴随着其他活动代理的变化。大约20%的恒星显示出模式频率和高度在相位上的变化，与观测到的太阳相反。
In the Sun, the frequencies of the acoustic modes are observed to vary in phase with the magnetic activity level. These frequency variations are expected to be common in solar-type stars and contain information about the activity-related changes that take place in their interiors. The unprecedented duration of Kepler photometric time-series provides a unique opportunity to detect and characterize stellar magnetic cycles through asteroseismology. In this work, we analyze a sample of 87 solar-type stars, measuring their temporal frequency shifts over segments of 90 days. For each segment, the individual frequencies are obtained through a Bayesian peak-bagging tool. The mean frequency shifts are then computed and compared with: (1) those obtained from a cross-correlation method; (2) the variation in the mode heights; (3) a photometric activity proxy; and (4) the characteristic timescale of the granulation. For each star and 90-day sub-series, we provide mean frequency shifts, mode heights, and characteristic timescales of the granulation. Interestingly, more than 60% of the stars show evidence for (quasi-)periodic variations in the frequency shifts. In the majority of the cases, these variations are accompanied by variations in other activity proxies. About 20% of the stars show mode frequencies and heights varying approximately in phase, in opposition to what is observed for the Sun.
影响因子：
6.5
作者：
T. Kallinger;J. Ridder;S. Hekker;S. Mathur;S. Mathur;B. Mosser;M. Gruberbauer;M. Gruberbauer;R. García;C. Karoff;J. Ballot;J. Ballot
通讯作者：
T. Kallinger;J. Ridder;S. Hekker;S. Mathur;S. Mathur;B. Mosser;M. Gruberbauer;M. Gruberbauer;R. García;C. Karoff;J. Ballot;J. Ballot
影响因子：
4.9
作者：
Aguirre, Victor Silva;Lund, Mikkel N.;Rendle, Ben
通讯作者：
Rendle, Ben
HARPS-N 重新审视 KEPLER-10 行星系统：炎热的岩石世界和固态海王星质量行星
DOI：
10.1088/0004-637x/789/2/154
发表时间：
2014
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Dumusque X
通讯作者：
Dumusque X