January 1, 2014.
Research conducted at UC Berkeley's Space Science Laboratory.
Type II radio bursts can be produced when a coronal mass ejection (CME) traveling faster than the local plasma speed of the ambient medium produces a shock. From the drift rate of type II bursts it is possible to calculate the velocity of the CME. We present a statistical survey of type II radio burst events during 2012-2013. Using radio observations we determine speeds of CME shocks as a means of setting limits on the Alfvén speed profile of the interplanetary medium as a function of distance from the sun. In particular we use observations from the WAVES instruments onboard the twin Solar TErrestrial RElations Observatory (STEREO) spacecraft, as well as onboard the WIND spacecraft. We pay special attention to the normalization of the density models used to fit the type II bursts through the use of in-situ measurements
The Sun and the Solar System
Hazel M. Bain
Space Sciences Laboratory at UC Berkeley (SSL)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).