Authors: James Leake (NASA: GSFC), Lars Daldorff (CUA), Peter Schuck (NASA:GSFC), Mark Linton (NRL)

While the evolution of electric currents in the solar corona is a major factor in the onset of dynamic and transient events, the best useful observations are of the magnetic field in the photosphere below. Recently, Schuck et al. (2022) developed a method to determine the magnetic imprint at the photosphere caused by electric currents in the corona above, using the method of Gauss. This method, CICCI, is able to infer the presence of coronal currents via the magnetic fields they create at the photosphere, somewhat challenging the often-assumed idea that electric currents in the convection zone are responsible for magnetic fields at and above the photosphere. While extremely useful for analyzing magnetic field observations at the photosphere, the precise nature of the currents cannot be obtained using CICCI alone. However, using MHD simulations of flux emergence through the photosphere from the convection zone and the eruption of the coronal structure formed from this emergence, and the well-known Biot-Savart law, the magnetic imprint of specific coronal currents present in the simulations can be evaluated. We present the HElmholtz Integrator for Simulations Tool (HEIST) which performs the Helmholtz decomposition on a volume of simulation data to calculate the Biot-Savart law and hence the magnetic field due to specific coronal currents, and use this to inform photospheric analysis using CICCI, which can be used on real observations of the photospheric magnetic field.