The long-term non-thermal energy release on the  small-scale flux level detected at radiowaves

Vladimir Bogod

Abstract

 The existence in quiescent solar active region the durable generation nonthermal emission on the time scale from several hours to several days is discovered. This emission is detected on the small-scale flux level (beginning from 3 - 5 Jy to 100 Jy) in decimeter wavelength range in the form of two types of sources.
 The first is the continuum source with high circular polarization (>70%) and the brightness temperatures (in the range 10^6 - 10^8 K), the second is the durable microbursts sources (DMB) with high degree of polarization (100%) and also with high brightness temperatures (>10^9 K).
 These sources are registrated on several wavelengths with the radiotelescope RATAN-600 both intensity and circular polarization in multi-asimuthal regime.
 Some possible interpretation are discussed and new method of measurements of weak coronal magnetic fields is offered.
 Likely, the detected types of sources point at the existence of a transition region above the active region where the nonthermal emission begins to prevail.
 
 

authors: Vladimir Bogod  and  Leonid Yasnov
 
institution: Vladimir Bogod;Special Astrophysical Observatory, 196140, St.Petersburg, Russia. vbog@gao.spb.ru
  Leonid Yasnov;  St.Petersburg University, St.Petersburg, Russia