P23

Presentation Title: A comparison of electric currents from a flux emergence MHD simulation and as reconstructed using a nonlinear force free field extrapolation
Author(s): Lucas A. Tarr (NSO) Kalman J. Knizhnik (NRL) Mark G. Linton (NRL)

Abstract:

The formation and distribution of electric currents in the solar atmosphere is a key physical process for heating the solar plasma and producing eruptions. Direct inference of currents from observations is extremely challenging, so one typically must rely on some method to reconstruct the 3D magnetic field from limited observations. This is usually accomplished by extrapolating the field into the coronal volume from a well-observed 2D boundary layer in the solar photosphere under the assumption that the plasma beta is very low and the field is ``[Lorentz] force free,'' meaning that the currents are aligned with the magnetic field. We demonstrate the dubious nature of these assumptions for an MHD simulation of an emerging flux rope but go on to explore the results of extrapolations that are applied to simulation anyway.