Физико-технический институт им. А.Ф. Иоффе
Санкт-Петербург, Россия
Нижний Новгород, Россия
The review of authors’ papers is devoted to the essential role of the Rayleigh—Taylor instability (RTI) as a trigger of flare energy release. We have analyzed two cases of RTI: near coronal loop footpoints and at the loop top. RTI near loop footpoints requires pre-heating of chromospheric plasma. This pre-heating can be realized due to Joule dissipation in partially ionized plasma under condition of the Cowling resistivity. RTI at the loop top arises in current-carrying coronal loop loaded by prominence. We have determined the conditions of RTI as a flare trigger in both cases. It is shown that RTI generates super-Dreicer electric field in the chromospheric parts of a loop. This is the promising solution of longstanding “number problem” of particle acceleration. RTI can be also a cause of prompt (~10 s) hot onset precursor events (HOPE).
Sun, flare trigger, Joule dissipation, particle acceleration
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