Comparative Analysis of Dayside Reconnection Models in Global Magnetosphere Simulations

Abstract

We test and compare a number of existing models predicting the location of magnetic reconnection at Earth's dayside magnetopause for various solar wind conditions. We employ robust image processing techniques to determine the locations where each model predicts reconnection to occur. The predictions are then compared to the magnetic separators, the magnetic field lines separating different magnetic topologies. The predictions are tested in distinct high-resolution simulations with interplanetary magnetic field (IMF) clock angles ranging from 30 to 165 degrees in global magnetohydrodynamic simulations using the three-dimensional Block-Adaptive Tree Solarwind Roe-type Upwind Scheme (BATS-R-US) code with a uniform resistivity, although the described techniques can be generally applied to any self-consistent magnetosphere code. Additional simulations are carried out to test location model dependence on IMF strength and dipole tilt. We find that most of the models match large portions of the magnetic separators when the IMF has a southward component, with the models saying reconnection occurs where the local reconnection rate and reconnection outflow speed are maximized performing best. When the IMF has a northward component, none of the models tested faithfully map the entire magnetic separator, but the maximum magnetic shear model is the best at mapping the separator in the cusp region where reconnection has been observed. Predictions for some models with northward IMF orientations improve after accounting for plasma flow shear parallel to the reconnecting components of the magnetic fields. Implications for observations are discussed.

arXiv comment15 page, 14 figures, accepted to Journal of Geophysical Research: Space Physics December 15, 2014, published January 20, 2015

References in corpus (4)

• The Orientation of the Reconnection X-line
• Satellite Observations of Separator Line Geometry of Three-Dimensional Magnetic Reconnection
• Tracing magnetic separators and their dependence on IMF clock angle in global magnetospheric simulations
• Three-dimensional simulations of the orientation and structure of reconnection X-lines

Cited by in corpus (6)

• Asymmetric magnetic reconnection with a flow shear and applications to the magnetopause
• How the IMF $B_y$ Induces a Local $B_y$ Component During Northward IMF $B_z$ and Characteristic Timescales
• Orientation and stability of asymmetric magnetic reconnection x-line
• Orientation of x-lines in asymmetric magnetic reconnection - mass ratio dependency
• Exact Vlasov-Maxwell equilibria for asymmetric current sheets
• The local dayside reconnection rate for oblique interplanetary magnetic fields