论文标题
Ogle Magellanic Cloud Collection的第一个夸张的头虫 - 超越径向模式
First Overtone Cepheids of the OGLE Magellanic Cloud Collection -- beyond radial modes
论文作者
论文摘要
我们已经分析了光引力透镜实验的光度法，用于在大小的麦哲伦云中的第一个泛音经典头孢菌素，以寻求径向模式以外的其他周期性。在某些情况下，我们使用了标准的连续晶格技术，然后使用时间依赖性预惠性。我们报告了双模径向搏动的新候选者。但是，我们检测到的大多数信号无法用径向模式来解释。我们报告516个具有周期比的双周期星，$ p _ {\ rm x}/p _ {\ rm 1o} $，范围为0.60和0.65。我们研究此类的特性以及解释这些周期性的模型的含义。我们还报告了28星，其中额外的可变性为较长时期，低于径向基本模式，中位周期比，$ p _ {\ rm 1o}/p _ {\ rm x} $ 0.684。该课程是对RR Lyrae明星中众所周知的班级的类似物。检测到数百个其他信号，这些信号不能归因于径向模式或上述类别。分析这些信号的统计特性。我们建议这些信号中的大多数对应于非radial模式。特别是，一个明显的分数可以归因于中等程度的非radial模式，并紧密连接到阶段比在0.60到0.65之间的类别。在数十个恒星中，靠近径向模式频率，观察到相对较大的振幅和相干信号，这可能代表另一个类。在27颗恒星中，检测到脉动的周期性调节。讨论了两个云之间其他频率内容的差异。
We have analysed Optical Gravitational Lensing Experiment photometry for first overtone classical Cepheids in the Large and Small Magellanic Clouds in search for additional periodicities beyond radial modes. We have used standard consecutive prewhitening technique in some cases followed by time-dependent prewhitening. We report new candidates for double-mode radial pulsations. However, majority of signals we have detected cannot be interpreted in terms of radial modes. We report 516 double-periodic stars with period ratios, $P_{\rm x}/P_{\rm 1O}$, in the range 0.60 and 0.65. We study the properties of this class and implications for model explaining these periodicities. We also report 28 stars in which additional variability is of longer period, below radial fundamental mode, with median period ratio, $P_{\rm 1O}/P_{\rm x}$, of 0.684. This class is an analogue of a class known in RR Lyrae stars. Hundreds of other signals were detected that cannot be attributed to radial modes or the above-mentioned classes. Statistical properties of these signals are analysed. We suggest that majority of these signals correspond to non-radial modes. In particular, a significant fraction can be attributed to non-radial modes of moderate degrees, tightly connected to a class with period ratios in between 0.60 and 0.65. In tens of stars, close to radial mode frequency, relatively large-amplitude and coherent signals are observed, that may represent yet another class. In 27 stars periodic modulation of pulsation was detected. Differences in additional frequency content between the two Clouds are discussed.
