Coronal Plasmas on the Sun and Nearby Stars,
Abstract
The Very Large Array(VLA) has been used to observe solar microwave sources with second of arc angular resolution. Both the quiescent, or non-flaring, microwave sources and the flaring ones are usually resolved. They are often associated with the apex and/or legs of the ubiquitous coronal loops, which heretofore have been observable only with X ray telescopes sent above the atmosphere. Multiple wavelength VLA observations can specify the strength, evolution and structure of the magnetic fields in coronal loops, while also providing constraints on the electron density and electron temperature of the plasma trapped within the coronal loops. The next section briefly reviews the thermal radiation mechanisms that account for most of the quiescent emission, while also pointing out that current amplified magnetic fields or non thermal radiation may be required in some instances. This is followed by a discussion of th e20 cm radiation of coronal loops and the thermal cyclotron lines that accurately specify their magnetic field strength. The 20 cm and X-ray emission of the coronal plasma are then compared. The coronae of nearby stars are discussed where coherent radiation processes seem to prevail.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1986
- Accession Number
- ADA173265
Entities
People
- Kenneth R. Lang
Organizations
- Tufts University