In this article, we investigate the formation and disruption of a coronal sigmoid from the active region (AR) NOAA 11909 on 07 December 2013, by analyzing multi-wavelength and multi-instrument observations. Our analysis suggests that the formation of the sigmoid initiated ≈ 1 hour before its eruption through a coupling between two twisted coronal loop systems. This sigmoid can be well regarded as of ‘transient’ class due to its short lifetime as the eruptive activities started just after ≈ 20 min of its formation. A comparison between coronal and photospheric images suggests that the coronal sigmoid was formed over a simple \(\beta \)-type AR which also possessed dispersed magnetic field structure in the photosphere. The line-of-sight photospheric magnetograms also reveal small-scale flux cancellation events near the polarity inversion line, and overall flux cancellation during the extended pre-eruption phase which suggest the role of tether-cutting reconnection toward the build-up of the flux rope. The disruption of the sigmoid proceeded with a two-ribbon eruptive M1.2 flare (SOL2013-12-07T07:29). In radio frequencies, we observe type III and type II bursts in meter wavelengths during the impulsive phase of the flare. The successful eruption of the flux rope leads to a fast coronal mass ejection (with a linear speed of ≈ 1085 km s⁻¹) in SOHO/LASCO field-of-view. During the evolution of the flare, we clearly observe typical “sigmoid-to-arcade” transformation. Prior to the onset of the impulsive phase of the flare, flux rope undergoes a slow rise (≈ 15 km s⁻¹) which subsequently transitions into a fast eruption (≈ 110 km s⁻¹). The two-phase evolution of the flux rope shows temporal associations with the soft X-ray precursor and impulsive phase emissions of the M-class flare, respectively, thus pointing toward a feedback relationship between magnetic reconnection and early CME dynamics.

在本文中，我们通过分析多波长和多仪器观测，研究了 2013 年 12 月 7 日活动区 (AR) NOAA 11909 的日冕 sigmoid 的形成和破坏。我们的分析表明，通过两个扭曲的日冕环系统之间的耦合，乙状结肠的形成大约在其喷发前 1 小时开始。这个 sigmoid 可以很好地被认为是“瞬态”类，因为它的生命周期很短，因为喷发活动在其形成约 20 分钟后就开始了。日冕和光球图像之间的比较表明，日冕 sigmoid 是在一个简单的\(\beta \)型 AR，在光球层中也具有分散的磁场结构。视线光球磁图还揭示了极性反转线附近的小规模通量抵消事件，以及在延长的喷发前阶段期间的整体通量抵消，这表明切断系绳重新连接对通量积累的作用绳索。乙状结肠的破坏伴随着两条带状喷发的 M1.2 耀斑 (SOL2013-12-07T07:29)。在无线电频率中，我们在耀斑的脉冲阶段观察到米波长的 III 型和 II 型爆发。磁通绳的成功喷发导致日冕物质的快速抛射（线速度≈ 1085 km s ^-1) 在 SOHO/LASCO 视野中。在耀斑的演变过程中，我们清楚地观察到典型的“sigmoid-to arcade”转换。在耀斑的脉冲阶段开始之前，通量绳经历缓慢上升（≈ 15 km s ^-1），随后转变为快速喷发（≈ 110 km s ^-1）。磁链的两相演化分别显示出与软 X 射线前兆和 M 级耀斑的脉冲相发射的时间关联，从而表明磁重联与早期 CME 动力学之间存在反馈关系。