Modelling loop-top X-ray source and reconnection outflows in solar flares with intense lasers
Modelling loop-top X-ray source and reconnection outflows in solar flares with intense lasers
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DOI：
10.1038/nphys1790
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发表时间：
2010-12
期刊：
影响因子：
19.6
通讯作者：
J. Zhong;Yutong Li;Xiaogang Wang;Jiaqi Wang;Q. Dong;C. Xiao;Shoujun Wang;Xun Liu;Lei Zhang
中科院分区：
文献类型：
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作者：
J. Zhong;Yutong Li;Xiaogang Wang;Jiaqi Wang;Q. Dong;C. Xiao;Shoujun Wang;Xun Liu;Lei Zhang
磁重联是穿过等离子体的相反方向的磁力线发生剧烈重排，将磁势转化为动能和热量的过程。它被认为在许多等离子体现象中发挥着重要作用，包括太阳耀斑、恒星形成和其他天体物理事件、激光驱动的等离子体射流和聚变等离子体不稳定性。由于实验室等离子体和天体物理等离子体之间存在巨大的尺度差异，通常很难将一种环境中研究的重联现象推断到另一种环境中观察到的重联现象。然而，在某些情况下，标度定律确实允许建立可靠的连接，例如太阳风与地球磁层之间相互作用的实验模拟。在这里，我们报告了大规模的实验室实验，通过与固体目标相互作用的重新连接流出来重现环顶式 X 射线源发射。我们的实验利用高强度激光与等离子体相互作用产生的兆高斯级磁场来重建类似于太阳耀斑中发生的磁重联拓扑。我们还确定了与重连接相关的分隔壁和扩散区域，其中离子在离子惯性长度的范围内与电子解耦。
Magnetic reconnection is a process by which oppositely directed magnetic field lines passing through a plasma undergo dramatic rearrangement, converting magnetic potential into kinetic energy and heat,. It is believed to play an important role in many plasma phenomena including solar flares,, star formation and other astrophysical events, laser-driven plasma jets,,, and fusion plasma instabilities. Because of the large differences of scale between laboratory and astrophysical plasmas, it is often difficult to extrapolate the reconnection phenomena studied in one environment to those observed in the other. In some cases, however, scaling laws do permit reliable connections to made, such as the experimental simulation of interactions between the solar wind and the Earth’s magnetosphere. Here we report well-scaled laboratory experiments that reproduce loop-top-like X-ray source emission by reconnection outflows interacting with a solid target. Our experiments exploit the mega-gauss-scale magnetic field generated by interaction of a high-intensity laser with a plasma to reconstruct a magnetic reconnection topology similar to that which occurs in solar flares. We also identify the separatrix and diffusion regions associated with reconnection in which ions become decoupled from electrons on a scale of the ion inertial length.