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We calculate particle acceleration during coronal mass ejection (CME) eruptions using combined magnetohydrodynamic and test-particle models. The 2.5D/3D CMEs are generated via the breakout mechanism. In this scenario a reconnection at the "breakout" current sheet (CS) above the flux rope initiates the CME eruption by destabilizing a quasi-static force balance. Reconnection at the flare CS below the erupting flux rope drives the fast acceleration of the CME, which forms flare loops below and produces the energetic particles observed in flares. For test-particle simulations, two times are selected during the impulsive and decay phases of the eruption. Particles are revealed to be accelerated more efficiently in the flare CS rather than in the breakout CS even in the presence of large magnetic islands. Particles are first accelerated in the CSs (with or without magnetic islands) by the reconnection electric field mainly through particle curvature drift. We find, as expected, that accelerated particles precipitate into the chromosphere, become trapped in the loop top by magnetic mirrors, or escape to interplanetary space along open field lines. Some trapped particles are reaccelerated, either via reinjection to the flare CS or through a local Betatron-type acceleration associated with compression of the magnetic field. The energetic particles produce relatively hard energy spectra during the impulsive phase. During the gradual phase, the relaxation of magnetic field shear reduces the guiding field in the flare CS, which leads to a decrease in particle energization efficiency. Important implications of our results for observations of particle acceleration in the solar coronal jets are also discussed. [ABSTRACT FROM AUTHOR]

We present observations and modeling of the magnetic field configuration, morphology, and dynamics of a large-scale, high-latitude filament eruption observed by the Solar Dynamics Observatory. We analyze the 2015 July 9–10 filament eruption and the evolution of the resulting coronal mass ejection (CME) through the solar corona. The slow streamer-blowout CME leaves behind an elongated post-eruption arcade above the extended polarity inversion line that is only poorly visible in extreme ultraviolet (EUV) disk observations and does not resemble a typical bright flare-loop system. Magnetohydrodynamic (MHD) simulation results from our data-inspired modeling of this eruption compare favorably with the EUV and white-light coronagraph observations. We estimate the reconnection flux from the simulation's flare-arcade growth and examine the magnetic-field orientation and evolution of the erupting prominence, highlighting the transition from an erupting sheared-arcade filament channel into a streamer-blowout flux-rope CME. Our results represent the first numerical modeling of a global-scale filament eruption where multiple ambiguous and complex observational signatures in EUV and white light can be fully understood and explained with the MHD simulation. In this context, our findings also suggest that the so-called stealth CME classification, as a driver of unexpected or "problem" geomagnetic storms, belongs more to a continuum of observable/nonobservable signatures than to separate or distinct eruption processes. [ABSTRACT FROM AUTHOR]