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arXiv · 0706.3648

Flare magnetic reconnection and relativistic particles in the 2003 October 28 event

C. Li·Y. H. Tang·Y. Dai·C. Fang·J. -C. Vial
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Abstract

An X17.2 solar flare occurred on 2003 October 28, accompanied by multi-wavelength emissions and a high flux of relativistic particles observed at 1AU. We present the analytic results of the TRACE, SOHO, RHESSI, ACE, GOES, hard X-ray (INTEGRAL satellite), radio (Onderejov radio telescope), and neutron monitor data. It is found that the inferred magnetic reconnection electric field correlates well with the hard X-ray, gamma-ray, and neutron emission at the Sun. Thus the flare's magnetic reconnection probably makes a crucial contribution to the prompt relativistic particles, which could be detected at 1 AU. Since the neutrons were emitted a few minutes before the injection of protons and electrons, we propose a magnetic-field evolution configuration to explain this delay. We do not exclude the effect of CME-driven shock, which probably plays an important role in the delayed gradual phase of solar energetic particles.

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C. Li, Y. H. Tang, Y. Dai, C. Fang, J. -C. Vial. 2007-06-25. Flare magnetic reconnection and relativistic particles in the 2003 October 28 event. https://doi.org/10.1051/0004-6361%3A20066966

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