VLA observations of impulsive solar flares at 4. 9 GHz

Journal Article · Sat Nov 15 04:00:00 EST 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158468· OSTI ID:6522334

Marsh, K A; Hurford, G J; Zirin, H; Hjellming, R M

Five impulsive solar microwave bursts (peak flux 2--1200 sfu) were observed during 1978 July 15--18, using the Very Large Array (VLA) at 4.9 GHz. The observations used up to 55 baselines providing up to 1'' spatial resolution and 10 s time resolution. A series of snapshot synthesis maps constructed as a function of time enabled complete mapping of source structure in one dimension and absolute location in two dimensions. It was found that, at the times of peak emission, all five flares were dominated by a single source whose size was in the range 12''-18''. Comparison with high-resolution H..cap alpha.. photographs and magnetograms showed that in each case the source was located between the H..cap alpha.. kernels, close to the magnetic neutral line. It was also observed that early in the rise phase of three of the flares, the microwave source exhibited a double structure.

• Research Organization: Palomer Observatory, California Institute of Technology
• OSTI ID: 6522334
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 241:4; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTROMAGNETIC RADIATION
ENERGY SPECTRA
INTERFEROMETRY
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
MAPS
MATHEMATICAL MODELS
MICROWAVE SPECTRA
RADIATIONS
RADIOWAVE RADIATION
SOLAR ACTIVITY
SOLAR FLARES
SOLAR RADIATION
SOLAR RADIOWAVE RADIATION
SPECTRA
STAR MODELS
STELLAR RADIATION