Flux relations between hard X-rays and microwaves for both impulsive and extended solar flares
Abstract
The correlation of peak fluxes between hard X-rays and microwaves from solar flares was reexamined separately for impulsive and extended bursts using 61 events recorded with both the hard X-ray spectrometer aboard the Hinotori satellite and the 17-GHz polarimeter at Nobeyama. (1) For impulsive bursts FR = 37.2 FX exp 0.77 with a small scatter of 0.3 orders of magnitude (rms) where FR is the 17-GHz peak flux in sfu and FX is the hard X-ray peak flux integrated over 67-152 keV in photons/s sq cm. Extended bursts deviate systematically above the regression line derived for impulsive bursts by a factor of 2-10 (excess of radio emission). A strong constraint is derived on the magnetic field intensity in the radio emitting region of impulsive bursts: the magnetic field intensity must be constant from flare to flare (approximately 1000 G with a scatter of less than a factor of 2). The radio excess of extended bursts can be explained by a relatively abundant population of relativistic electrons trapped in large magnetic loops.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- 1985
- Bibcode:
- 1985PASJ...37..155K
- Keywords:
-
- Microwave Emission;
- Solar Flares;
- Solar Radio Emission;
- Solar X-Rays;
- Radiant Flux Density;
- Solar Magnetic Field;
- Solar Radio Bursts;
- Synchrotron Radiation;
- Solar Physics