论文标题
探索Helioseiscic旅行时间异常与太阳周期中大型活动区域的出现之间的联系24
Exploring the Connection between Helioseismic Travel Time Anomalies and the Emergence of Large Active Regions during Solar Cycle 24
论文作者
论文摘要
我们研究了在Helioseiscic和Magement Imager（HMI）观察到的46个大型活性区域之前出现的声波的平均相位行进时间的偏差。在我们的研究中，我们考虑了两种不同的程序来获得平均相位旅行时间，通过最大程度地减少互相关和参考之间的差异以及Gabor小波拟合程序。我们将平均相位行进时间偏差的时间序列与表面磁场交叉，并确定峰值相关时间滞后。我们还计算了扰动指数 - 扰动指数（超过安静的太阳阈值的区域集成的平均相位行进时间偏差），并将峰值扰动指数的时间与相关时间滞后进行比较。我们发现，从差异最小化过程中得出的滞后时间先于46个活性区域的36个磁通出现，并且该滞后时间与最大磁通速率具有明显的相关性。但是，只有28个活动区域在出现前24至48小时的范围内具有峰值扰动指数时间。此外，我们研究了出现的活跃区域的性质与热震信号的强度之间的关系。
We investigate deviations in the mean phase travel time of acoustic waves preceding the emergence of 46 large active regions observed by the Helioseismic and Magnetic Imager (HMI). In our investigation, we consider two different procedures for obtaining the mean phase travel time, by minimizing the difference between cross-correlations and a reference, as well as the Gabor wavelet fitting procedure. We cross-correlate the time series of mean phase travel time deviations with the surface magnetic field and determine the peak correlation time lag. We also compute the perturbation index--the area integrated mean phase travel time deviations exceeding quiet sun thresholds--and compare the time of peak perturbation index with the correlation time lag. We find that the lag times derived from the difference minimization procedure precede the flux emergence for 36 of the 46 active regions, and that this lag time has a noticeable correlation with the maximum flux rate. However, only 28 of the active regions have peak perturbation index times in the range of 24 to 48 hours prior to the flux emergence. Additionally, we examine the relationship between properties of the emerged active regions and the strength of helioseismic signals prior to their emergence.
