J. VLA (Very Large Array) of a solar noise storm
The first Very Large Array (VLA) observations of the Sun at 92 cm wavelength (328 MHz) are presented. A 3-hr solar noise storm was detected; it consisted of burst-like spikes superimposed on a slowly varying background, and both storm components were 95 + or - 5% right-hand circularly polarized. A long duration soft x-ray event preceded the radio radiation by 30 m, suggesting a disturbance moving outwards at a velocity of v = 78 km/s. The 92 cm noise storm was resolved with an angular resolution of 9 sec for time intervals as short as 13 s. During the onset and early phases, the storm consisted of four compact sources, each with an angular diameter of 40 sec, oriented within an elongated source with angular dimensions of 40 sec by 200 sec. During the subsequent hour the most intense emission was located in two 40 sec sources separated by 100 sec. Snapshot maps revealed a persistent elongated source at successive peaks, with a scatter in the source position. A systematic position shift of Deta Theta sub I greater than or = 15 sec can be produced by the Earth's ionosphere, but these effects can be removed by frequent observations of a nearby calibrator source. The observations confirm previously reported trends for a decrease in source size at higher frequencies, but they suggest a hitherto unresolved complexity in source structure.
- Research Organization:
- Tufts Univ., Medford, MA (USA)
- OSTI ID:
- 6319774
- Report Number(s):
- N-87-23561; NASA-CR-180219; NAS-1.26:180219; AD-A-179664; TRN: 87-030840
- Country of Publication:
- United States
- Language:
- English
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VLA observations of a solar noise storm
VLA (Very Large Array) observations of a solar-noise storm
Related Subjects
GENERAL PHYSICS
SOLAR RADIO BURSTS
CONFIGURATION
SOLAR X-RAY BURSTS
EXPERIMENTAL DATA
MAGNETIC STORMS
NOISE
RADIO TELESCOPES
SOLAR ACTIVITY
ANTENNAS
DATA
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELECTRONIC EQUIPMENT
EQUIPMENT
INFORMATION
NUMERICAL DATA
RADIATIONS
RADIO EQUIPMENT
RADIOWAVE RADIATION
TELESCOPES
640104* - Astrophysics & Cosmology- Solar Phenomena