School of Astronomy and Space Science, Nanjing University, Nanjing, 210023, China.
Physics Department, Montana State University, Bozeman, MT, 59717, USA.
Nat Commun. 2018 Feb 15;9(1):692. doi: 10.1038/s41467-018-03056-8.
The heating of the Sun's corona has been explained by several different mechanisms including wave dissipation and magnetic reconnection. While both have been shown capable of supplying the requisite power, neither has been used in a quantitative model of observations fed by measured inputs. Here we show that impulsive reconnection is capable of producing an active region corona agreeing both qualitatively and quantitatively with extreme-ultraviolet observations. We calculate the heating power proportional to the velocity difference between magnetic footpoints and the photospheric plasma, called the non-ideal velocity. The length scale of flux elements reconnected in the corona is found to be around 160 km. The differential emission measure of the model corona agrees with that derived using multi-wavelength images. Synthesized extreme-ultraviolet images resemble observations both in their loop-dominated appearance and their intensity histograms. This work provides compelling evidence that impulsive reconnection events are a viable mechanism for heating the corona.
太阳日冕的加热已经通过几种不同的机制来解释,包括波耗散和磁重联。虽然这两者都被证明有能力提供所需的能量,但在由测量输入驱动的观测的定量模型中都没有被使用。在这里,我们表明,脉冲重联能够产生与极紫外线观测一致的活动区日冕,无论是定性还是定量上。我们计算出与磁 Footpoint 和光球等离子体之间的速度差成正比的加热功率,称为非理想速度。在日冕中重新连接的通量元的长度尺度约为 160km。模型日冕的差分发射量与使用多波长图像得出的发射量一致。合成的极紫外线图像在它们的环主导外观和强度直方图上都与观测结果相似。这项工作提供了令人信服的证据,表明脉冲重联事件是加热日冕的一种可行机制。