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Gamma-Ray Polarimetry of Two X-Class Solar Flares

Steven E. Boggs·W. Coburn·E. Kalemci
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Abstract

We have performed the first polarimetry of solar flare emission at gamma-ray energies (0.2-1 MeV). These observations were performed with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) for two large flares: the GOES X4.8-class solar flare of 2002 July 23, and the X17-class flare of 2003 October 28. We have marginal polarization detections in both flares, at levels of 21% +/- 9% and -11% +/- 5% respectively. These measurements significantly constrain the levels and directions of solar flare gamma-ray polarization, and begin to probe the underlying electron distributions.

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Steven E. Boggs, W. Coburn, E. Kalemci. 2005-10-19. Gamma-Ray Polarimetry of Two X-Class Solar Flares. https://doi.org/10.1086/498930

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