Microwave imaging of a solar limb flare: Comparison of spectra and spatial geometry with hard X-rays

Journal Article · Sun Dec 15 04:00:00 EST 1985 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/163769· OSTI ID:5802270

Schmahl, E J; Kundu, M R; Dennis, B R

We have mapped a solar limb flare using the VLA at 6 cm wavelength with 8'' spatial resolution, simultaneously with hard X-ray spectral and spatial observations with the Solar Maximum Mission satellite. Microwave flux records from 2.8-19.6 Ghz have enabled us to determine the burst spectrum, which has a maximum at 10 GHz. The rising side of each of three microwave subbursts within the flare were simultaneous to < or approx. =1 s, with hard X-ray rises toward maxima. The flux spectrum and area of the burst sources were used to determine the number of electrons producing gyrosynchrotron emission (approx.1 x 10/sup 33/), the strength of the magnetic field (approx.550 G), and the energy distribution of gyrosynchrotron-emitting electrons (approx.E/sup -3/). Applying the thick target model to the hard X-ray flux spectrum, the number of high energy (E>25 keV) electrons responsible for the X-ray bursts was found to be Nroughly-equal110/sup 36/, and the electron energy distribution was approx.E/sup -5/, significantly different from the parameters derived from the microwave observations.

• Research Organization: Astronomy Program, University of Maryland
• OSTI ID: 5802270
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 299:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics &amp; Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
HARD X RADIATION
IMAGES
INTERFEROMETRY
IONIZING RADIATIONS
LEPTONS
MAPS
POLARIZATION
RADIATIONS
RADIOWAVE RADIATION
SOLAR ACTIVITY
SOLAR ELECTRONS
SOLAR FLARES
SOLAR PARTICLES
SOLAR RADIATION
SOLAR RADIO BURSTS
SOLAR RADIOWAVE RADIATION
SOLAR X-RAY BURSTS
SPECTRA
STELLAR RADIATION
X RADIATION
X-RAY SPECTRA