Shock waves and type II radiobursts in the interplanetary medium

✍ Scribed by A. Boischot; A. C. Riddle; J. B. Pearce; J. W. Warwick

• Publisher: Springer
• Year: 1980
• Tongue: English
• Weight: 406 KB
• Volume: 65
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00152802

✦ Synopsis

The planetary radio astronomy experiment on the Voyager spacecraft observed several type II solar radiobursts at frequencies below 1.3 MHz; these correspond to shock waves at distances between 20R| and 1 AU from the Sun. We study the characteristics of these bursts and discuss the information that they give on shock waves in the interplanetary medium and on the origin of the high energy electrons which give rise to the radioemission. The relatively frequent occurence of type II bursts at large distances from the Sun favors the hypothesis of the emission by a longitudinal shockwave. The observed spectral characteristics reveal that the source of emission is restricted to only a small portion of the shock. From the relation between type II bursts, type III bursts and optical flares, we suggest that some of the type II bursts could be excited by type III burst fast electrons which catch up the shock and are then trapped.