Accession Number:

ADA171925

Title:

Solar Burst Precursors and Energy Build Up at Microwave Wavelengths,

Descriptive Note:

Corporate Author:

TUFTS UNIV MEDFORD MA DEPT OF PHYSICS

Personal Author(s):

Report Date:

1986-01-01

Pagination or Media Count:

5.0

Abstract:

We summarize high-resolution microwave observations VLA of heating and magnetic triggering in coronal loops. Magnetic changes that precede solar eruptions on time scales of tens of minutes involve primarily emerging coronal loops and the interaction of two or more loops. Thermal cyclotron lines have been detected in coronal loops, suggesting the presence of hot current sheets that enhance emission from relatively thin layers of enhanced temperature and constant magnetic field. These current sheets may play a role in the excitation of solar bursts. A filament-associated source with a high brightness temperature and steep radiation spectrum occurs above a region of apparently weak photospheric field. This source might be attributed to currents that enhance coronal magnetic fields. Compact phi5 sec transient sources with lifetimes of 30 to 60 minutes have also been detected in regions of apparently weak photospheric field. We conclude by comparing VLA observations of coronal loops with simultaneous SMM-XRP observations.

Subject Categories:

  • Astrophysics
  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE