Research advances in solar physics at National Astronomical Observatories of Chinese Academy of Sciences
Year: 2021
Type: article
Abstract: In 2001, the National Astronomical Observatories of Chinese Academy of Sciences (NAOC) was established with the reorganization of the astronomical community within the Chinese Academy of Sciences then. Several solar physics research groups in the former Beijing Astronomical Observatory of Chinese Academy of Sciences were incorporated into NAOC. During the past 20 years NAOC has successfully operated several world class solar telescopes, including the multi-channel solar magnetic field telescope and the solar radio broadband dynamic spectrometers and other advanced solar telescopes. It has developed the solar full-disk optical and magnetic field monitoring system and the Mingantu spectral radioheliograph (MUSER) and other new generation of observing instruments. Presently, the accurate solar infrared magnetic measuring system (AIMS), the main payload of the China’s first space solar telescope (Advanced Space-based Solar Observatory, ASO-S)—the full-disk magnetograph (FMG), the meter-decameter wavelength spectral radioheliograph, and the radio interplanetary scintillation (IPS) telescope are under construction. The paper gives an overview for the original or notable research advances made by NAOC solar staff in the past 2 decades, which includes the research of solar magnetic field in the photosphere, coronal hole, quiet region and solar networks, new magnetic field extrapolation method and a magnetic flux rope that existed before a flare/coronal mass ejection eruption that was firstly revealed with the extrapolation method, new magnetic helicity calculation method, the oscillating characteristics of magnetic helicity transportation and the unbalance between the northern and southern hemispheres which presents a new observation constraint and challenge to the solar dynamo model, sunspot bright walls, direct observational evidence of magnetic reconnection in the solar lower atmosphere and ubiquitous tornadoes in the solar atmosphere that may be possible energy sources of corona heating. A large number of unique solar radio spectral fine structures have been discovered and explained theoretically based on the observed data of NAOC. The microwave Zebra patterns, multi-timescale quasi-periodic pulsations, lace bursts, and spikes present the diversity and complexity of the energy release related to the solar flares. They provide an important tool for diagnosing the physical conditions of flaring source regions and useful probe for revealing the details of magnetic reconnection, particles accelerations and propagations. The magnetic field in the source region and the initial process of coronal mass ejections are systematically identified. For the first time, the relationship between the trans-equatorial filaments and coronal mass ejections is developed. The theory that coronal mass ejection is the natural result of magnetic helicity accumulation in the corona is put forward, which lays a physical foundation for the prediction of CMEs. The results of solar activity predictions have been successfully applied to the space environment guarantee of several manned space missions, the Chang’e project and the Olympic Games. This paper further proposes that the future China will mainly develop the solar magnetic field measurements, the solar radio observations and the deep-space explorations for the great breakthrough, which will promote the tackling of a series of solar and terrestrial physics scientific problems, including the origin of the solar magnetic field, solar cycles, coronal heating, solar eruptions and its influential mechanism on solar-terrestrial space environment.
DOI: 10.1360/tb-2020-1645
Author: Yihua Yan
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W3155558847