天文学进展2017，Vol.35Issue(2)：149-174,26.DOI:10.3969/j.issn.1000-8349.2017.02.01
电子回旋脉泽辐射机制在太阳物理中的进展
Research Progress of Electron Cyclotron Maser Emission on Solar Physics
摘要
Abstract
Electron-cyclotron maser (ECM) emission is a well-known radiation emission mechanism in astrophysics. It has been extensively applied to various nonthermal coherent radio emission, especially to the short-timescale coherent radio bursts. Excitation of electron cyclotron maser radiation requires two basic conditions. One is the inversion distribution of the energetic electrons in the direction perpendicular to the ambient magnetic field. The other is the escape diffculty that requires the local electron cyclotron frequency over the plasma frequency. These two conditions are hardly satisfied in the corona under the conventional solar atmosphere models, which limit the application of ECM emission mechanism to solar radio astronomy. In general, flare associated energetic electrons are accelerated initially mainly along the magnetic field, it means that these energetic electrons do not have enough free energy to drive ECM emission. After the energetic electrons leave the acceleration site and propagate in the solar atmosphere, the energy of the energetic electrons in the parallel orientation can be transfer to the perpendicular orientation, and form an anisotropic distribution due to the interaction of energetic electrons with magnetic field and plasma waves. For the escape diffculty, a density depletion duct in the corona is necessary and may be rational as optical observations show fibrous density structures exist commonly in the corona. This paper presents a systematic review on the recent development of ECM emission mechanism,especially on the new models which may overcome the above diffculties and can be applied in several kinds of solar radio bursts, such as type Ⅰ bursts, type Ⅱ bursts, and type V bursts. Some perspectives on the study of ECM mechanism and solar radio emission processes are also presented.关键词
辐射机制/电子回旋脉泽不稳定性/射电暴/幂律谱Key words
emission mechanism/electron-cyclotron maser (ECM) instability/radio bursts/power-law spectrum分类
天文与地球科学引用本文复制引用
唐建飞,吴德金,赵国清,陈玲..电子回旋脉泽辐射机制在太阳物理中的进展[J].天文学进展,2017,35(2):149-174,26.基金项目
新疆维吾尔自治区自然科学基金青年项目(2013211B40) （2013211B40）
