An Extreme Ultraviolet Explorer Atlas of Seyfert Galaxy Light Curves: Search for Periodicity
An Extreme Ultraviolet Explorer Atlas of Seyfert Galaxy Light Curves: Search for Periodicity
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塞弗特星系光曲线的极端紫外线探索图集：寻找周期性
DOI：
10.1086/346106
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
H. L. Marshall
中科院分区：
文献类型：
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作者：
J. Halpern;K. Leighly;H. L. Marshall
极紫外线探测器（EUVE）卫星上的深度测量仪器获得了14个塞弗特星系和类星体的长的、几乎连续的软X射线光变曲线，持续时间为5-33天。我们提出了一个统一的减少这些数据，占总共231天的观察。这些光变曲线中有几个非常适合于寻找周期性或准周期性振荡，这些振荡在几小时到几天的范围内，可能是从~108 M黑洞周围的内吸积盘中的动力学过程中预期的。三个最长观测值的光变曲线和周期图显示了可能是瞬态周期的特征：RX J0437.4-4711为0.89天，Ton S180为2.08天，1H 0419-577为5.8天。这些信号的统计显著性使用Timmer & König的方法进行估计，该方法仔细考虑了Seyfert光变曲线的红噪声特性。结果是RX J0437.4-4711和Ton S180中的信号在红噪声方面超过95%置信度，而1H 0419-577仅为64%显著性。这些周期值似乎与观测的长度无关，这在三种情况下是相似的，但它们确实大致与物体的光度成比例，如果光度与黑洞质量成比例，这在动力学场景中是可以预期的。
The Deep Survey instrument on the Extreme Ultraviolet Explorer (EUVE) satellite obtained long, nearly continuous soft X-ray light curves of 5-33 days duration for 14 Seyfert galaxies and quasars. We present a uniform reduction of these data, which account for a total of 231 days of observation. Several of these light curves are well suited to a search for periodicity or quasi-periodic oscillations in the range of hours to days that might be expected from dynamical processes in the inner accretion disk around ~108 M☉ black holes. Light curves and periodograms of the three longest observations show features that could be transient periods: 0.89 days in RX J0437.4-4711, 2.08 days in Ton S180, and 5.8 days in 1H 0419-577. The statistical significance of these signals is estimated using the method of Timmer & König, which carefully takes into account the red-noise properties of Seyfert light curves. The result is that the signals in RX J0437.4-4711 and Ton S180 exceed 95% confidence with respect to red noise, while 1H 0419-577 is only 64% significant. These period values appear unrelated to the length of the observation, which is similar in the three cases, but they do scale roughly as the luminosity of the object, which would be expected in a dynamical scenario if luminosity scales with black hole mass.