Generation of highly energetic electrons at reconnection outflow shocks during solar flares

Mann, G., A. Warmuth, and H. Aurass, Generation of highly energetic electrons at reconnection outflow shocks during solar flares, A&A, 494, 669-675 (2009) (ADS)

The cartoon

(click on the image for a larger version)

This is the standard CSHKP cartoon, rendered here with extraordinary clarity and applied to a vexing problem: the acceleration of all the electrons. The concentric lozenges towards the bottom represent the conjectural fast-mode standing shock that results (in these 2D cartoons) automatically from the geometry. Here it must have a density of about 109 cm-3 if the interesting signature seen in the radio spectrogram is attributed to the plasma frequency. The Archivist would guess that the cartoon predicts a slow drift to lower frequencies, but that is the opposite of what was observed. This paper has the best observations the highly anticipated termination shock, but it is striking that the cartoon predicts that it should always happen, and yet it seldom does. One problem is that we simply don't detect Alfvénic outflows, and so perhaps shocks can't routinely occur.

Date: 2010 June 16

Update: 2019 November 26