Chinese scientists reveal the basic trigger mechanism of solar eruptions

(a) Current slice diagrams at different moments, in which the magnetic flux rope (MFR) generated during the explosion and the current sheet (CS) below and the shock wave (Shock) above are marked at the third moment; (b) Velocity slices at different moments.

The maximum velocity and Alfen Mach number corresponding to each moment are marked on the graph; (c) The three-dimensional structure of the magnetic flux rope formed during the explosion process (left) and the three-dimensional turbulent reconnection current sheet Structure (right)

Funded by the National Natural Science Foundation of China (approval numbers: 41822404, 41731067, 42030204, 41861164026, 41874202, 41774150, 11925302, and 11873086), Professor Jiang Chaowei and Feng Xueshang of Harbin Institute of Technology joined forces with the University of Science and Technology of China and the University of Alabama in Huntsville , Yunnan Observatory, and many other units at home and abroad, using its self-developed high-precision numerical calculation method, confirmed that the bipolar magnetic field in the solar atmosphere (corona) can effectively trigger solar eruptions, revealing the cause of the coronal magnetic field The basic mechanism of energy release
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The research result is titled "A fundamental mechanism of solar eruption initiation", which will be published in the journal "Nature.

Solar eruptions, mainly including solar flares and coronal mass ejections, are the most spectacular astronomical phenomenon in the solar system and the driving source of disastrous space weather.
They have a serious impact on human high-tech activities such as aerospace, navigation and communications, and deep space exploration.

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Since the first observation of solar flares in 1859, people have gradually realized that the essence of solar eruptive activity is the rapid release of magnetic energy in the corona, and two theories have been proposed: the instability of the magnetic flux rope system and the bursting of the magnetic multipole field.

Based on his self-developed numerical calculation model, Jiang Chaowei and others adopted the bipolar magnetic field configuration commonly found in the source area of ​​the solar burst, driven by the photospheric shear current, to achieve the highest-precision full three-dimensional solar burst simulation so far, which is self-consistent The entire process of coronal magnetic field energy from slowly accumulating to sharply releasing and erupting was simulated (Figure 1)
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The research results show that in the quasi-static evolution process driven by the photosphere shear, a thin layer of strong current (current sheet) will spontaneously form inside the magnetic arch and trigger solar eruptions to form coronal mass ejections and shock waves.

The research has enhanced people's understanding of the solar atmospheric energy release, promoted the development of solar burst theory, and has important scientific significance for the establishment of physics-based space weather forecasting models