论文标题
GJ 436的磁活性和可变性的研究
A Study of the Magnetic Activity and Variability of GJ 436
论文作者
论文摘要
我们使用HARPS的光谱数据，跨越14年，以及来自Narval的其他数据，介绍了GJ 436的磁性活动研究，落入竖琴观测中。我们研究Caii H＆K，Heid3，Nai Doublet，H $α$和CAII IRT三胞胎线，并探索它们之间的线性相关性。使用完整的HARPS数据集，我们发现指标H $α$ vs CAII H＆K＆H $α$ vs HEI与HEI相关。从Narval数据集中，涵盖了一个观察到的时代，我们找到了Caii irt $ _ {3} $ vs caii irt $ _ {2} $＆caii＆caii＆caii＆_ irt $ _ {3} $ vs H $α$ index与n $α$相关。我们使用广义的Lomb-Scargle周期图研究了这些指数变化中的长期和短期周期性。对于CAII H＆K，NAI和H $α$指数，我们分别检测到2470.7d（〜6。8年），1861.6d（〜5.1岁）和2160.9d（〜5.9岁）的长期期限，与GJ 436的光度计周期一致。将“合并方差”技术应用于H $α$＆NAI指数，我们发现〜2500D是活动周期机制的时期，与检测到的2470.7d期间非常吻合。对于CAII H＆K和H $α$索引，我们检测到$ 39.47^{+0.11} _ { - 0.15} $ D和$ 40.46^{+0.44} _ { - 0.52} $ D的短期期间，$ 40.46^{+0.44} $ d。预先定位长期周期性后，检测到恒星旋转。在分析个体观察时期时也检测到了它。
We present a magnetic activity study of GJ 436 using spectroscopic data from HARPS, spanning over 14 years, and additional data from NARVAL, falling within the HARPS observations. We study the CaII H&K, HeID3, NaI doublet, H$α$ and CaII IRT triplets lines and explore linear correlations between them. Using the full HARPS dataset, we found indices H$α$ vs CaII H&K & H$α$ vs HeI to correlate positively. From the NARVAL dataset, covering one observing epoch, we found CaII IRT$_{3}$ vs CaII IRT$_{2}$ & CaII IRT$_{3}$ vs H$α$ index to correlate negatively. We investigate long and short-term periodicity in these index variations using the Generalised Lomb-Scargle periodogram. For CaII H&K, NaI and H$α$ indices, we detect long-term periods of 2470.7d (~ 6.8 years), 1861.6d (~ 5.1 years) and 2160.9d (~ 5.9 years) respectively, consistent with GJ 436's photometric cycle of ~ 7.4 years. Applying the "Pooled Variance" technique to H$α$ & NaI indices, we found ~ 2500d to be the period of an activity cycle mechanism, in good agreement with the detected 2470.7d period. For CaII H&K and H$α$ indices, we detect short-term periods of $39.47^{+0.11}_{-0.15}$d and $40.46^{+0.44}_{-0.52}$d respectively, identified as the stellar rotation period. The stellar rotation is detected after prewhitening the long-term periodicity. It is detected as well in the analysis of individual observing epochs.
