๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

On the reconciliation of simultaneous microwave imaging and hard X-ray observations of a solar flare

โœ Scribed by N. Nitta; S. M. White; E. J. Schmahl; M. R. Kundu


Publisher
Springer
Year
1991
Tongue
English
Weight
699 KB
Volume
132
Category
Article
ISSN
0038-0938

No coin nor oath required. For personal study only.

โœฆ Synopsis


We have compared microwave imaging data for a small flare with simultaneous hard X-ray spectral observations. The X-ray data suggest that the power-law index 5 of the energy distribution of the radiating electrons is 5.3 (thick-target) which differs significantly from the estimate (b = 1.4) from a homogeneous optically-thin gyrosynchrotron model which fits the radio observations well. In order to reconcile these results, we explore a number &options. We investigate a double power-law energy spectrum for the energetic electrons in the flare, as assumed by other authors: the power law is steep at low energies and much flatter at the higher energies which produce the bulk of the microwaves. The deduced break energy is about 230 keV if we tentatively ignore the X-ray emission from the radio-emitting electrons: however, the emission of soft photons by the flat tail strongly contributes to the observed hard X-ray range and would flatten the spectrum there. A thin-target model for the X-ray emission is also inconsistent with radio data. An inhomogeneous gyrosynchrotron model with a number of free parameters and containing an electron distribution given by the thick-target X-ray model could be made to fit the radio data.


๐Ÿ“œ SIMILAR VOLUMES


Simultaneous high spatial resolution obs
โœ S. Enome ๐Ÿ“‚ Article ๐Ÿ“… 1987 ๐Ÿ› Springer ๐ŸŒ English โš– 410 KB

Results of simultaneous high-resolution microwave and X-ray two-dimensional imaging observations are briefly reviewed. It is shown that seven events published in the literature are not homogeneous but rather diverse with respect to spatial structure, mutual relations on position or shape. An outlook

Microwave and hard X-Ray observations of
โœ P. Kaufmann; F. M. Strauss; J. E. R. Costa; B. R. Dennis; A. Kiplinger; K. J. Fr ๐Ÿ“‚ Article ๐Ÿ“… 1983 ๐Ÿ› Springer ๐ŸŒ English โš– 509 KB

Simultaneous microwave and X-ray observations are presented for a solar flare detected on May 8, 1980 starting at 19:37 UT. The X-ray observations were made with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission and covered the energy range from 28-490 keV with a time resolution of 10 m

On the production of hard X-rays in sola
โœ G. M. Simnett; M. G. Haines ๐Ÿ“‚ Article ๐Ÿ“… 1990 ๐Ÿ› Springer ๐ŸŒ English โš– 613 KB

The problem of producing the hard X-ray burst at the onset of solar flares may be thought of in terms of the problem of producing the non-thermal electrons which emit the X-rays via bremsstrahlung. Electron acceleration to relativistic energies without similar ion acceleration is difficult to achiev

Soft X-ray and microwave observations of
โœ H. S. Hudson; K. Ohki ๐Ÿ“‚ Article ๐Ÿ“… 1972 ๐Ÿ› Springer ๐ŸŒ English โš– 696 KB

Hot regions in solar flares produce X-radiation and microwaves by thermal processes. Recent X-ray data make it possible to specify the temperature and emission measure of the soft X-ray source, by using, for instance, a combination of the 1-8 A (peak response at about 2 keV) and the 0.5-3 ]k (peak r