Physics Dept. Seminar

February 22, Thursday (** SPECIAL DAY**)

Investigations of Solar Activities of Various Scales in Both Theory and Observation

Dr. Jun Lin

Yunnan Astronomical Observatories

Chinese Academy of Sciences

(Solar Physics, Host: Bin Chen)

Room: ECE 202

**CORRECTED TIME: 10:15 am - 11:15 am with 10 am teatime

Magnetic field is the fundamental topic of solar physics. It is involved in all the activities of a large variety of scales. Magnetic reconnection is a ubiquitous process that frequently occurs in the environment, which fills with plasma and magnetic field. In this talk, I shall introduce recent works of the Group of Solar Activities and CME Theory at the Yunnan Astronomical Observatories in Kunming, Yunnan, China. These works include studies in both theories and observations of various solar activities and related topics over a large range of scales. We investigated the CME structures seen in EUV during its propagation and gave a unique explanation. Fine structures inside large-scale current sheet behind CME are analyzed; they play an important role in converting the magnetic energy into the other types of energy in the large-scale current sheet, and they result from turbulence as a result of the tearing mode instability. Small-scale brightening in the low atmosphere is studied numerically, and its implication for corona heating is discussed. Finally, a deep space mission that aims to detect the current sheet behind CME will also be introduced briefly.