Observation of a Reversal of Breakout Reconnection Preceding a Jet: Evidence of Oscillatory Magnetic Reconnection?
Observation of a Reversal of Breakout Reconnection Preceding a Jet: Evidence of Oscillatory Magnetic Reconnection?
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DOI：
10.3847/1538-4357/ab0c9d
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发表时间：
2019-03
期刊：
影响因子：
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通讯作者：
Junchao Hong;Jiayan Yang;Huadong Chen;Y. Bi;Bo Yang;Hechao Chen
中科院分区：
文献类型：
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作者：
Junchao Hong;Jiayan Yang;Huadong Chen;Y. Bi;Bo Yang;Hechao Chen
最近的研究表明，涉及微丝喷发的太阳喷流可能是在众所周知的磁爆发机制下引发的。在这些射流开始之前或刚刚开始时，在开放区域和在其核心中带有微丝的射流基座拱廊的外部之间应该有一个电流片，其中发生突破磁重联。在本文中，我们提出了由位于射流底部的两根微细丝喷发产生的射流。在喷发开始前，在喷流底座附近直接检测到电流片，表明存在磁爆发机制。然而，我们进一步发现当前工作表发生了转变。当前片材的长度首先缩短至零，但随后朝相对于其初始方向的正交方向伸长。当前片的变化导致突破重新连接的逆转，因为转变之前的流入和流出区域分别变成转变之后的流出和流入区域。因此，我们认为这一观察结果为所谓的振荡重联提供了证据，振荡重联是由一系列重联反转定义的，但尚未证明存在于太阳大气的真实等离子体环境中。
Recent studies have revealed that solar jets involving minifilament eruptions may be initiated under the well-known magnetic-breakout mechanism. Before or just at the onset of those jets, there should be a current sheet, where breakout magnetic reconnection takes place, between open fields and the outside of the jet-base arcade carrying a minifilament in its core. In this paper we present a jet produced by the eruption of two minifilaments lying at the jet base. A current sheet is directly detected near the jet base before the onset of the eruption, suggesting the magnetic-breakout mechanism. However, we further find that the current sheet undergoes a transition. The current sheet first shortens to zero in length, but then lengthens toward an orthogonal direction relative to its initial orientation. The change of the current sheet gives rise to a reversal of the breakout reconnection, as the inflow and outflow regions before the transition become the outflow and inflow regions after the transition, respectively. We therefore propose that this observation provides evidence for the so-called oscillatory reconnection that is defined by a series of reconnection reversals but not yet proven to exist in the real plasma environment of the solar atmosphere.