Sophie Masson, Spiro K. Antiochos, C. Rick DeVore
Impulsive solar energetic particles (SEP) bursts are frequently observed in association with so-called eruptive flares consisting of a coronal mass ejection (CME) and a flare. These highly prompt SEPs are believed to be accelerated by the flare rather than by a CME shock, but in the standard flare model the accelerated particles should remain trapped in the corona or in the ejected plas- moid. In this case, however, the particles would reach the Earth only after a delay of many hours to a few days. We present a new model that can account for the prompt injection of energetic particles onto open interplanetary magnetic flux tubes. The basic idea underlying the model is that magnetic reconnection between the ejection and external open field allows for the release of the ener- getic particles. We demonstrate the model using 2.5D MHD simulations of a CME/flare event. The model system consists of a multipolar field with a coro- nal null point and with photospheric shear imposed at a polarity inversion line, as in the standard breakout model, but we include an isothermal wind in this system, which leads to the presence of open flux neighboring the eruption. We present the results of the simulation and compare these results with the standard observations of impulsive SEPs. We also discuss the implications of the model for observations and for further calculations.
View original:
http://arxiv.org/abs/1301.0654
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