Chinese and foreign scientists have made important progress in the study of magnetic reconnection of solar flares

Source: Xinhua Net

Kunming, 10 Feb (Xinhua) -- A reporter learned from the Yunnan Astronomical Observatory of the Chinese Academy of Sciences on the 10th that the Fuxian Lake Solar Observation and Research Base of the Yunnan Astronomical Observatory of the Chinese Academy of Sciences has made important progress in the study of the fine physical process of magnetic reconnection, and researchers have found for the first time a rapid magnetic reconnection with a twisted structure magnetic island in a solar flare. The relevant research results were recently published in the international authoritative journal Nature Communications.

The results were completed by scholars from the Yunnan Astronomical Observatory of the Chinese Academy of Sciences, Harbin Institute of Technology (Shenzhen), the University of Potsdam in Germany, the University of St Andrews in the United Kingdom, the National Astronomical Observatory of the Chinese Academy of Sciences and the National Space Science Center of the Chinese Academy of Sciences.

According to Yan Xiaoli, the first author of the paper and a researcher at the Yunnan Astronomical Observatory of the Chinese Academy of Sciences, magnetic reconnection is a physical process in which two sets of magnetic field lines with reverse components are close to each other and reconnected. In this process, the magnetic field lines will be annihilated at the current sheet, so that the magnetic energy is converted into kinetic energy, thermal energy, radiation energy and so on of the plasma. Magnetic reconnection is a basic process of rapid release of magnetic energy in the plasmas prevalent in the universe, and plays an extremely important role in astrophysics, space physics, and laboratory plasma physics.

The researchers mainly used the high-time and high-spatial resolution data of the one-meter new vacuum solar telescope at the Fuxian Lake Solar Observatory of the Yunnan Observatory, combined with the data of multiple foreign space satellites, to study in detail the large solar flare event that occurred on February 2, 2014. In this event, the one-meter new vacuum solar telescope observed the most complete magnetic reconnection feature to date. At the same time, the satellite spectroscopic data show that there is very strong non-thermal radiation in the magnetic reconnection current sheet. Extreme ultraviolet observations have revealed that a large number of plasma groups (magnetic islands) form in the current sheet. Through data-driven, high-resolution numerical simulations, the researchers recreated the formation process of plasma groups and confirmed that these plasma groups are small magnetic ropes with strong winding structures.

Yan Xiaoli said that the study reveals the fine physical process of rapid magnetic reconnection in solar flares, further deepens the understanding of the basic physical process of magnetic reconnection, is of great significance for the study of the physical characteristics and activity laws of solar activity, and also provides an important reference for the study of the flare phenomenon of other celestial bodies and high-energy radiation, space physics and magnetic energy dissipation in laboratory plasma physics.

The study lasted for many years and was funded by the National Natural Science Foundation of China, the Chinese Academy of Sciences and a number of research funds and projects in Yunnan Province.