M is for Magnifique Part Deux

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Revision as of 19:14, 14 February 2011

Introduction

In this nugget, we would like to continue our analysis of the M class flare of October 16th 2010 (SOL2010-10-16T19:12) which we have previously discussed in a past nugget.

CMEs

Such a moving shock front might be indicative of a CME.

Figure X: The radio spectrum from GBSRBS showing associated type III and type II radio bursts. Type II radio bursts are signatures of traveling shock waves and are frequently associated with CMEs.

Flare morphology

To the solar west of the main flare site a significant elongated structure is present in multiple wavelengths, including 171A and 304 A. The presence of this structure is made more interesting by the fact that it reacts to the eruption of the main flare.

Figure Y: An elongated ribbon structure to the solar west of the flare site, visible in 171 A and 304 A.

Correlation maps

To study the morphology of this flare we introduce the method of cross-correlation mapping. This procedure is designed to uncover correlations between different portions of an image series.

The method is to select one pixel in the data cube to serve as the 'master pixel'. This pixel is represented by a time series. To create the correlation map, the master pixel is cross-correlated with every other pixel time series. Any pixel may be chosen to serve as the master pixel.

In this way we create two types of map. First, a map showing the level of correlation for a particular lag, and secondly a map showing the lag corresponding to the maximum correlation.

We choose a master pixel located in the bottom-left corner of the ribbon structure. In multiple wavelengths, we can see the difference in the speed of propagation of heating along the structure as the energy from the main flare is deposited.

Conclusion