Abstract
Recent progress and future prospects in diagnostics of energetic electrons and ions in the flares are reviewed, together with the roles they play in the flare as a whole. Most of the discussion centres on hard X-ray and gamma-ray and thermal plasma emission data, rather than on radio sources. Since
Solar Maximum Mission
and
Hinotori
there has been major progress in all areas of flare electron diagnostics. Electron spectra are now recoverable with some precision, electrons with energies above 10 MeV are known to be highly anisotropic, and indications are available of the spatial distribution of electrons at 20 keV. Timescales of electron acceleration are now known to be shorter than 0.1 s. Energetic electrons are believed to carry much of the flare power. Ion diagnostics are more limited. For greater than 1 MeV ions the flux, spectrum and acceleration timescale are now quite well known. Low energy ions are hard to diagnose but have been invoked as a flare heating mechanism alternative to electron beams. The problems with beam heating models are discussed with special attention to the problems of the low energy proton model and its only direct diagnostic, Hα impact polarization. Finally, theoretical problems associated with return currents and with accelerator requirements are discussed and attention is drawn to the possible importance of entropy as well as energy considerations.
Subject
Pharmacology (medical),Complementary and alternative medicine,Pharmaceutical Science
Cited by
6 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
1. Analysis of observations of linear polarization for H α emission of flares and moustaches;Bulletin of the Crimean Astrophysical Observatory;2011-06
2. RADIO EMISSION FROM SOLAR FLARES;Annual Review of Astronomy and Astrophysics;1998-09
3. Protons in flares;Space Science Reviews;1995-08
4. Flare energy transport by conduction and radiation;Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences;1991-09-16
5. References;Astronomy and Astrophysics Library