Solar Type II Radio Bursts and IP Type II Events

Details Solar Type II Radio Bursts and IP Type II Events Solar Type II Radio Bursts and IP Type II Events

Apr 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005apj...623.1180c&link_type=abstract

The Astrophysical Journal, Volume 623, Issue 2, pp. 1180-1194.

Astronomy and Astrophysics

Astronomy

35

Shock Waves, Sun: Coronal Mass Ejections (Cmes), Sun: Radio Radiation

Scientific paper

We have examined radio data from the WAVES experiment on the Wind spacecraft in conjunction with ground-based data in order to investigate the relationship between the shocks responsible for metric type II radio bursts and the shocks in front of coronal mass ejections (CMEs). The bow shocks of fast, large CMEs are strong interplanetary (IP) shocks, and the associated radio emissions often consist of single broad bands starting below ~4 MHz; such emissions were previously called IP type II events. In contrast, metric type II bursts are usually narrowbanded and display two harmonically related bands. In addition to displaying complete dynamic spectra for a number of events, we also analyze the 135 WAVES 1-14 MHz slow-drift time periods in 2001-2003. We find that most of the periods contain multiple phenomena, which we divide into three groups: metric type II extensions, IP type II events, and ``blobs and bands.'' About half of the WAVES listings include probable extensions of metric type II radio bursts, but in more than half of these events, there were also other slow-drift features. In the 3 yr study period, there were 31 IP type II events; these were associated with the very fastest CMEs. The most common form of activity in the WAVES events, blobs and bands in the frequency range between 1 and 8 MHz, fall below an envelope consistent with the early signatures of an IP type II event. However, most of this activity lasts only a few tens of minutes, whereas IP type II events last for many hours. In this study we find many examples in the radio data of two shock-like phenomena with different characteristics that occur simultaneously in the metric and decametric/hectometric bands, and no clear example of a metric type II burst that extends continuously down in frequency to become an IP type II event. The simplest interpretation is that metric type II bursts, unlike IP type II events, are not caused by shocks driven in front of CMEs.

Affiliated with

Also associated with

No associations

Rating

Solar Type II Radio Bursts and IP Type II Events does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Solar Type II Radio Bursts and IP Type II Events, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solar Type II Radio Bursts and IP Type II Events will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1454314