Wave Excitation by Energetic Ring-distributed Electron Beams in the Solar Corona
Zhou,Xiaowei1,2; Mu?oz,Patricio A.3; Büchner,J?rg2,3; Liu,Siming1
Source PublicationThe Astrophysical Journal
AbstractAbstract We analyzed properties of waves excited by mildly relativistic electron beams propagating along the magnetic field with a ring-shape perpendicular momentum distribution in neutral and current-free solar coronal plasmas. These plasmas are subject to both the beam and the electron cyclotron maser instabilities driven by the positive momentum gradients of the ring-beam electron distribution in the directions parallel and perpendicular to the ambient magnetic field, respectively. To explore the related kinetic processes self-consistently, 2.5D fully kinetic particle-in-cell simulations were carried out. To quantify excited wave properties in different coronal conditions, we investigated the dependences of their energy and polarization on the ring-beam electron density and magnetic field. In general, electrostatic waves dominate the energetics of waves, and nonlinear waves are ubiquitous. In weakly magnetized plasmas, where the electron cyclotron frequency ωce is lower than the electron plasma frequency ωpe, it is difficult to produce escaping electromagnetic waves with frequency ω?>?ωpe and small refractive index (k and c are the wavenumber and the light speed, respectively). Highly polarized and anisotropic escaping electromagnetic waves can, however, be effectively excited in strongly magnetized plasmas with ωce/ωpe?≥?1. The anisotropies of the energy, circular polarization degree (CPD), and spectrogram of these escaping electromagnetic waves strongly depend on the number density ratio of the ring-beam electrons to the background electrons. In particular, their CPDs can vary from left-handed to right-handed with the decrease of the ring-beam density, which may explain some observed properties of solar radio bursts (e.g., radio spikes) from the solar corona.
KeywordSolar magnetic reconnection Solar corona Solar coronal radio emission
WOS IDIOP:0004-637X-891-1-ab6a0d
PublisherThe American Astronomical Society
Citation statistics
Document Type期刊论文
Affiliation1.Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, 210034, People's Republic of China
2.Max Planck Institute for Solar System Research, G?ttingen, Germany
3.Center for Astronomy and Astrophysics, Technical University Berlin, Berlin, Germany
Recommended Citation
GB/T 7714
Zhou,Xiaowei,Mu?oz,Patricio A.,Büchner,J?rg,et al. Wave Excitation by Energetic Ring-distributed Electron Beams in the Solar Corona[J]. The Astrophysical Journal,2020,891(1).
APA Zhou,Xiaowei,Mu?oz,Patricio A.,Büchner,J?rg,&Liu,Siming.(2020).Wave Excitation by Energetic Ring-distributed Electron Beams in the Solar Corona.The Astrophysical Journal,891(1).
MLA Zhou,Xiaowei,et al."Wave Excitation by Energetic Ring-distributed Electron Beams in the Solar Corona".The Astrophysical Journal 891.1(2020).
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Zhou,Xiaowei]'s Articles
[Mu?oz,Patricio A.]'s Articles
[Büchner,J?rg]'s Articles
Baidu academic
Similar articles in Baidu academic
[Zhou,Xiaowei]'s Articles
[Mu?oz,Patricio A.]'s Articles
[Büchner,J?rg]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Zhou,Xiaowei]'s Articles
[Mu?oz,Patricio A.]'s Articles
[Büchner,J?rg]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.