Split-band structure in type II radio bursts from the sun
Abstract
The split-band structure of type II bursts is here attributed to simultaneous plasma-frequency emission from plasma ahead of and behind a type II shock front. The amount of band splitting is then a measure of the shock strength. Since the shock strength is the ratio of the disturbance speed to the Alfven velocity and since the disturbance speeds can be derived from measured frequency-drift rates and an assumed coronal-density model, it is possible to derive the magnetic field strength along the path of the type II disturbance. Shock strengths in the range of magnetic Mach numbers between 1.2 and 1.7 and magnetic fields in the range 0.3 to 4 G are thus obtained for nine split-band type II bursts.
- Publication:
-
Astrophysical Letters
- Pub Date:
- 1975
- Bibcode:
- 1975ApL....16Q..23S
- Keywords:
-
- Plasma Radiation;
- Shock Fronts;
- Solar Magnetic Field;
- Solar Spectra;
- Type 2 Bursts;
- Atmospheric Models;
- Mach Number;
- Magnetic Effects;
- Radio Spectra;
- Solar Atmosphere;
- Solar Corona;
- Spectroheliographs;
- Spectrum Analysis;
- Solar Physics