Using an MHD simulation of near tail reconnection associated with a flow burst and the collapse (dipolarization) of the inner tail in combination with test particle tracing we study the acceleration and flux increases of energetic oxygen ions (O+). The characteristic orbits, distributions, and acceleration mechanisms are governed by the dimensionless parameter
This paper represents the second part of an investigation of the acceleration of energetic oxygen ions from encounters with a dipolarization front (DF), based on test particle tracing in the fields of an MHD simulation. In this paper, we focus on distributions in the plasma sheet boundary layer (PSBL). O+beams close to the plasma sheet boundary are found to be less pronounced and/or delayed against the H+beams. The reason is that these particles are accelerated by nonadiabatic motion in the duskward electric field such that O+ions gain the same amount of energy, but only 1/4 of the speed of protons. This causes a delay and larger equatorward displacement by the
- NSF-PAR ID:
- 10369919
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 126
- Issue:
- 7
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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