Double plasma resonance instability as a source of solar zebra emission

0494615 - ASÚ 2019 RIV FR eng J - Journal Article
Benáček, J. - Karlický, Marian
Double plasma resonance instability as a source of solar zebra emission.
Astronomy & Astrophysics. Roč. 611, March (2018), č. článku A60. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GA16-13277S; GA ČR(CZ) GA17-16447S
Institutional support: RVO:67985815
Keywords : instabilities * numerical methods * radio radiation
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.209, year: 2018

First using the multi-mode model, we study details of the double plasma resonance instability. We show how the distribution function of hot electrons changes during this instability. Then we show that there is a very good agreement between results obtained by the multi-mode and specific-mode models, which is caused by a dominance of the wave with the maximal growth rate. Therefore, for computations in a broad range of model parameters, we use the specific-mode model. We compute the maximal growth rates of the double plasma resonance instability with a dependence on the ratio between the upper-hybrid omega(UH) and electron-cyclotron omega(ce) frequency. We vary temperatures of both the hot and background plasma components and study their effects on the resulting growth rates. The results are compared with the analytical ones. We find a very good agreement between numerical and analytical growth rates. We also compute saturation energies of the upper-hybrid waves in a very broad range of parameters. We find that the saturation energies of the upper-hybrid waves show maxima and minima at almost the same values of omega(UH) =omega(ce) as the growth rates, but with a higher contrast between them than the growth rate maxima and minima.
Permanent Link: http://hdl.handle.net/11104/0287725