SM43A-07
Sub-solar Magnetopause Observation and Simulation of a Tripolar Guide-Magnetic Field Perturbation
Thursday, 17 December 2015: 14:58
2018 (Moscone West)
Stefan Eriksson, Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, Paul Cassak, West Virginia University, Department of Physics and Astronomy, Morgantown, WV, United States, Alessandro Retino, CNRS, Paris Cedex 16, France and Forrest Mozer, University of California Berkeley, Berkeley, CA, United States
Abstract:
The Polar satellite recorded two reconnection exhausts within 6 min on 1 April 2001 at a rather symmetric sub-solar magnetopause that displayed different out-of-plane signatures for similar solar wind conditions. The first case was reported by Mozer et al. [2002] and displayed a bipolar guide field supporting a quadrupole Hall field consistent with a single X-line. The second case, however, shows the first known example of a tripolar guide-field perturbation at Earth’s magnetopause reminiscent of the types of solar wind exhausts that Eriksson et al. [2014; 2015] have reported to be in agreement with multiple X-lines. A dedicated particle-in-cell simulation is performed for the prevailing conditions across the magnetopause. We propose an explanation in terms of asymmetric Hall magnetic fields due to a presence of a magnetic island between two X-lines, and discuss how higher resolution MMS observations can be used to further study this problem at the magnetopause.
