Very Large Array Observations of Solar Active Regions. IV. Structure and Evolution of Radio Bursts from 20 cm Loops.

Abstract

The Very Large Array (VLA) has been used to study the structure and evolution of six solar bursts near 20 cm wavelength. In most cases the burst emission has been resolved into looplike structures with total lengths, approx, 3 x 10 to the minus 9th power cm, brightness temperatures approx. 10 to the 7th to 8th power K and degress of circular polarization approx. or 90%. Changes in the total intensity and circular polarization of the bursts occur on timescales as short as ten seconds. The individual peaks of one multiple component burst originated in different locations within a magnetically complicated region. Preburst heating and circular polarizaton changes respectively occurred minutes before the onset of the impulsive phase of two bursts. In one case a loop system emerged in the vicinity of the impulsive source, and two adjacent loop systems may have emerged and triggered the burst.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1983
Accession Number
ADA133907

Entities

People

  • Kenneth R. Lang
  • Robert F. Willson

Organizations

  • Tufts University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Amplitude
  • Brightness
  • Circular Polarization
  • Contracts
  • Emission
  • Hard X Rays
  • High Temperature
  • Intensity
  • Magnetic Fields
  • Observation
  • Physics
  • Polarization
  • Security
  • Soft X Rays
  • Solar Observatories
  • Universities
  • X Rays

Fields of Study

  • Physics

Readers

  • Solar Physics