An Alternative View of the Masuda Flare

Nugget
Number:	125
1st Author:	Nariaki Nitta
2nd Author:
Published:	2010 April 12
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Introduction

The "Masuda flare" [1] has defined flare physics for a generation of solar astronomers, but do we understand its message? Regular readers of the RHESSI Science Nuggets know that the bulk of hard X-ray emission in solar flares comes from the foot-points of a coronal magnetic loop structure. These X-rays result from interaction of energetic electrons, presumably accelerated in the corona, with the denser solar atmosphere. We also have learned about the hard X-ray sources actually in the corona [2], which are usually weaker than the foot-point sources. These take a variety of forms and appear at different times or phases in the flare development. Among these the Masuda flare, shown in Figure 1, remains unique. In this Nugget we question how typical this flare is.

Figure 1: The original Masuda flare, showing images from [1] hard X-ray and soft X-ray telescopes.

References

[1] loop-top hard X-ray source in a compact solar flare as evidence for magnetic reconnection

[2] Hard X-ray sources