In this Letter, we study the kinematic properties of ascending hot blobs associated with confined flares. Taking advantage of high-cadence extreme-ultraviolet images provided by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we find that for the 26 events selected here, the hot blobs are first impulsively accelerated outward, but then quickly slow down to motionlessness. Their velocity evolution is basically synchronous with the temporal variation of the Geostationary Operational Environmental Satellite soft X-ray flux of the associated flares, except that the velocity peak precedes the soft X-ray peak by minutes. Moreover, the duration of the acceleration phase of the erupting blobs is moderately correlated with that of the flare rise phase. For nine of the 26 cases, the erupting blobs even appear minutes prior to the onset of the associated flares. Our results show that a fraction of confined flares also involve the eruption of a magnetic flux rope, which sometimes is formed and heated prior to the flare onset. We suggest that the initiation and development of these confined flares are similar to that of eruptive ones, and the main difference may lie in the background field constraint, which is stronger for the former than for the latter.

在这封信中，我们研究了与受限火炬相关的上升热斑点的运动学特性。利用由太阳动力学天文台上的大气成像组件提供的高强度极紫外图像，我们发现，对于此处选择的26个事件，热斑点首先被向外冲动加速，但随后迅速减速至静止。它们的速度演变基本上与相关火炬的地球静止运行环境卫星软X射线通量的时间变化同步，只是速度峰值先于软X射线峰值数分钟。此外，爆发斑点的加速阶段的持续时间与火炬上升阶段的持续时间适度相关。在这26个案例中，有9个 爆发的斑点甚至出现在相关耀斑发作之前的几分钟。我们的结果表明，部分受限的火炬还涉及磁通绳的喷发，有时在火炬发作之前就形成并加热了它。我们认为这些局限性耀斑的萌发和发育与爆发性耀斑的相似，主要区别可能在于背景场约束，前者比后者强。