Speaker
Description
Using test-particle simulations we study the acceleration of suprathermal electrons at an ICME-driven quasi-perpendicular shock on 2000 Feb 11 observed by Wind spacecraft. The downstream electron distribution in several energy channels from ~0.3 to ~40 keV are obtained assuming an initial distribution based on the observed upstream electron intensities. It is shown that in each energy channel the ratio of downstream to upstream intensities peaks at about 90° pitch angle, and in each pitch angle direction the downstream electron energy spectral index is much larger than the theoretical index of diffusive shock acceleration. In addition, assuming the dominance of shock drift acceleration mechanism and the conservation of the phase space density before and after the acceleration, we find that the estimated drift length is proportional to the electron energy but the drift time is almost energy independent. Furthermore, we construct a theoretical model based on SDA to describe the energy dependence of drift length and drift time. These results indicate the importance of SDA in the acceleration of electrons by quasi-perpendicular shocks, consistent with Yang et al. conclusion.
Keywords
acceleration of particles, shock waves, turbulence
| Subcategory | Theoretical Results |
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