Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections

Details Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections

Dec 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agufmsh43b1518g&link_type=abstract

American Geophysical Union, Fall Meeting 2006, abstract #SH43B-1518

Physics

7513 Coronal Mass Ejections (2101), 7514 Energetic Particles (2114)

Scientific paper

Acceleration mechanisms of solar energetic particles are usually associated with Coronal Mass Ejections (CME) in the solar corona environment. CME structures propagate at speeds up to 1000 km/s interacting with the slower solar wind. The kinetic to magnetic pressure ratios are very low for both plasmas (β << 1), and typical Mach numbers of CMEs are around 3. Solar energetic particles with energies up to several MeV are produced by these structures and are detected at 1 AU. The acceleration mechanism of these particles is still under strong debate and is the subject of the work presented here. We have used the massively parallel 3D hybrid particle code, dHybrid, to simulate CMEs. Two simulation setups, mimicking the corona environment, were used to capture the physics of the accelerating particles. In the first scenario the solar wind flows quasi-parallel to the background magnetic field and a slab of plasma is shocked against the solar wind plasma. In the second scenario, the CME frozen-in magnetic field is also included by setting a perpendicular magnetic field in the coronal mass ejection zone and the quasi-parallel field in the solar wind zone. In both cases simulation parameters were set in order to guarantee the plasma β and relative Mach numbers, similar to those in the realistic solar conditions. While in the first case, waves are easier to analyze and to study, thus providing insight on the wave-particle interactions, the second case provides a more realistic scenario and the physics underlying the acceleration mechanisms can be directly assessed. Our simulations show the formation of Alfvèn like waves upstream of the shock, in the solar wind, due to the quasi-parallel flow. These waves form in both simulation scenarios and are seen to interact with the coronal mass ejection particles through wave-particle interaction, accelerating them mainly in the perpendicular directions through a surfatron like mechanism, but also in the shock direction. The energy gains of the most energetic particles are analyzed, and the acceleration mechanisms are explored via test particle simulations.

Affiliated with

Also associated with

No associations

Rating

Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hybrid Simulations of Particle Acceleration in Coronal Mass Ejections will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-968455