论文标题
纵向丝振荡通过两个C级耀斑增强
Longitudinal filament oscillations enhanced by two C-class flares
论文作者
论文摘要
在本文中，我们报告了2010年10月18日活跃区域（AR）11112在活跃区域（AR）11112的多波长观察结果。灯丝由两个部分，即东部（EP）和西部部分（WP）组成。我们专注于EP的纵向振荡，这些EP通过同一AR中的两个同源C级耀斑增强。 C1.3耀斑被限制在没有CME的情况下。细丝的EP和WP都略有干扰，并在耀斑中幸存下来。 5小时后，WP的喷发产生了C2.6耀斑和狭窄的喷气状CME。显然在EP中确定了三个振荡线（$ _a $，thd $ _b $，thd $ _c $），它们的振荡自然被两个耀斑分为三个阶段。初始振幅的范围为1.6至30毫米，平均值为$ \ sim $ 14毫米。该期间的范围从34到73分钟，平均值为$ \ sim $ 53分钟。磁倾角的曲率半径估计为29至133毫米，平均值为$ \ sim $ 74毫米。阻尼时间从$ \ sim $ 62到$ \ sim $ 96分钟，平均值为$ \ sim $ 82分钟。 $τ/p $的值在1.2和1.8之间。对于EP中的$ _a $，振幅通过C1.3耀斑后的6.1毫米至6.8毫米增强，并在C2.6耀斑之后再增加到21.4毫米。由于耀斑扰动而导致的周期变化在20 \％以内。 C2.6火炬后，衰减变得更快。 据我们所知，这是首次报告大振幅，纵向灯丝振荡的报告。数值模拟很好地重现了$ _a $的振荡。模拟幅度和周期接近观察到的值，而在最后阶段的阻尼时间更长，这意味着应考虑到辐射损失的其他机制。
In this paper, we report the multiwavelength observations of a very long filament in active region (AR) 11112 on 2010 October 18. The filament was composed of two parts, the eastern part (EP) and western part (WP). We focus on longitudinal oscillations of the EP, which were enhanced by two homologous C-class flares in the same AR. The C1.3 flare was confined without a CME. Both EP and WP of the filament were slightly disturbed and survived the flare. After 5 hrs, eruption of the WP generated a C2.6 flare and a narrow, jet-like CME. Three oscillating threads (thd$_a$, thd$_b$, thd$_c$) are obviously identified in the EP and their oscillations are naturally divided into three phases by the two flares. The initial amplitude ranges from 1.6 to 30 Mm with a mean value of $\sim$14 Mm. The period ranges from 34 to 73 minutes with a mean value of $\sim$53 minutes. The curvature radii of the magnetic dips are estimated to be 29 to 133 Mm with a mean value of $\sim$74 Mm. The damping times ranges from $\sim$62 to $\sim$96 minutes with a mean value of $\sim$82 minutes. The value of $τ/P$ is between 1.2 and 1.8. For thd$_a$ in the EP, the amplitudes were enhanced by the two flares from 6.1 Mm to 6.8 Mm after the C1.3 flare and further to 21.4 Mm after the C2.6 flare. The period variation as a result of perturbation from the flares was within 20\%. The attenuation became faster after the C2.6 flare. To the best of our knowledge, this is the first report of large-amplitude, longitudinal filament oscillations enhanced by flares. Numerical simulations reproduce the oscillations of thd$_a$ very well. The simulated amplitudes and periods are close to the observed values, while the damping time in the last phase is longer, implying additional mechanisms should be taken into account apart from radiative loss.
