论文标题
在日期差异中，婚内周期性信号的波动特征的新证据
New evidences for the fluctuation characteristic of intradecadal periodic signals in length-of-day variation
论文作者
论文摘要
日期变化（DLOD）中的核次内波动被认为可能在核心运动中起重要作用。在先前的研究中，已经检测到了两个有5.9yr和8.5yr（分别称为SYO和EYO）的核发生内振荡（分别称为SYO和EYO）。但是，自1962年以来，SYO和EYO是否具有稳定的阻尼趋势，以及是否可能对SYO/EYO的地磁混乱来源进行辩论。在这项研究中，基于不同时间跨度的不同方法和DLOD记录，我们显示出强大的证据，以证明SYO和EYO自1962年以来没有稳定的阻尼趋势，并且我们发现可能还有7.6yr的信号。为了证明它是否是周期性信号，我们使用最佳序列估计方法堆叠35全局地磁记录，结果还显示了一个7.6yr的周期性信号，该信号具有Y2，-2空间分布，并且具有高度一致的与DLOD中7.6yr信号的一致性同步性。在确认混蛋与EYO/SYO的峰/山谷没有特别的一致性之后，我们确认地磁混蛋似乎与SYO/EYO TIME系列及其激发系列的突然变化有关。因此，我们终于建议混蛋是SYO/EYO的激发源。同时，在使用反卷积方法之后，我们估计SYO和EYO的周期P和质量因子Q分别为[P = 5.85 +/- 0.06yr，Q大于180]和[P = 8.455 +/- 0.17yr，Q，Q大于350]。
The intradecadal fluctuations in the length-of-day variation (dLOD) are considered likely to play an important role in core motions. Two intradecadal oscillations, with 5.9yr and 8.5yr periods (referred to as SYO and EYO, respectively), have been detected in previous studies. However, whether the SYO and the EYO have stable damping trends since 1962 and whether geomagnetic jerks are possible excitation sources for the SYO/EYO are still debated. In this study, based on different methods and dLOD records with different time span, we show robust evidences to prove that the SYO and the EYO have no stable damping trends since 1962, and we find that there is also a possible 7.6yr signal. To prove whether it is a periodic signal, we use the optimal sequence estimation method to stack 35 global geomagnetic records, the results also show an 7.6yr periodic signal which has an Y2,-2 spatial distribution, and it has a high degree of consistent synchronicity with the 7.6yr signal in dLOD. After confirming that the jerks have no special consistency with the peaks/valleys of the EYO/SYO, we confirm that the geomagnetic jerks seem to be related to sudden changes in the SYO/EYO time series and their excitation series; so we finally suggest that jerks are possible excitation sources of the SYO/EYO. Meanwhile, after using a deconvolution method, we estimate that the period P and quality factor Q of the SYO and the EYO are [P=5.85+/-0.06yr, Q larger than 180] and [P=8.455+/-0.17yr, Q larger than 350], respectively.
