A comparison of type II shock speeds

✍ Scribed by R. J. Thompson; J. A. Kennewell; N. P. Prestage

• Book ID: 104642795
• Publisher: Springer
• Year: 1996
• Tongue: English
• Weight: 599 KB
• Volume: 166
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00149404

✦ Synopsis

Type II radio bursts are produced by material moving outwards in the solar atmosphere. Their drift in frequency allows the calculation of the radial speed with which the shock is moving -very basic information in assessing the likelihood that the shock will reach the Earth and its time of arrival. This paper compares the shock speeds derived from radio bursts observed by the Swept Frequency Interferometric Radiometer (SFIR) equipment at the US Air Force Radio Solar Telescope Network (RSTN) of observatories with those measured with the Culgoora radiospectrograph operated by IPS Radio and Space Services. The SFIR shock speeds are found to be 1.5-3.0 times larger than the Culgoora values which are consistent with earlier results. This difference appears to originate from the incorrect interpretation of events as a result of the smaller frequency range of the SFIR equipment.