Radiation Signatures of Solar Energy Release at mm-Wavelengths: Advanced Circuit211 Model

摘要

Pulsating and explosive time profiles of mm-wave solar bursts observed at211u001eMetsaehovi in terms of the energy release in single current-carrying loop are 211u001eexplained. The authors suppose that the electric current in a loop is driven by 211u001ethe photospheric convective flows. The flare occurs due to the flute instability 211u001ewhich gives the penetration of partially ionized plasma of the chromosphere into 211u001ethe current channel of a loop and consequently the loop resistanc grows by many 211u001eorders of magnitude. The feedback of the deviation of the loop magnetic field on 211u001ethe energy release rate was taken into account. Two regimes of energy release are 211u001estudied: (1) Pulsating energy release in rarefield current loop with plasma beta 211u001eis much less than 1; (2) Explosive energy release in a loop with the gradient of 211u001egas pressure of about Ampere force. The authors have shown that using two 211u001ementioned regimes and its combination one can explain different time behavior of 211u001ethe flares, for example, several quasi-periodic pulses, and pulsations with 211u001eincreasing amplitude at pre-flash phase followed by explosive enhancement of the 211u001eemission at flash phase.