1. In situ observations of particle acceleration in shock-shock interaction
- Author
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Hannu Koskinen, Neus Agueda, Heli Hietala, Emilia Kilpua, Stuart Nylund, K. Andreeova, and Rami Vainio
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,Soil Science ,Astrophysics ,Aquatic Science ,Oceanography ,01 natural sciences ,Acceleration ,Geochemistry and Petrology ,0103 physical sciences ,Earth and Planetary Sciences (miscellaneous) ,Bow shock (aerodynamics) ,Interplanetary magnetic field ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Water Science and Technology ,Physics ,education.field_of_study ,Ecology ,Paleontology ,Forestry ,Fermi acceleration ,Computational physics ,Shock (mechanics) ,Particle acceleration ,Geophysics ,Space and Planetary Science ,Physics::Space Physics ,Astrophysical plasma - Abstract
[1] We use detailed multispacecraft observations to study the interaction of an interplanetary (IP) shock with the bow shock of the Earth on August 9–10, 1998. We can distinguish four different phases of particle acceleration in the shock-shock interaction: (1) formation of magnetic contact with IP shock and the seed population of energetic particles accelerated by it, (2) reacceleration of this population by the bow shock, (3) first order Fermi acceleration as the two shocks approach each other, and (4) particle acceleration and release as the shocks collide. Such a detailed analysis was made possible by the particularly advantageous quasi-radial interplanetary magnetic field configuration. To our knowledge this is the first time the last phase of acceleration at a shock-shock collision has been reported using in situ space plasma observations.
- Published
- 2011