VFISV Inversion Code Documentation for SOLIS/VSM Pipeline Implementation

Abstract: Spectral line inversion codes are tools used to interpret spectropolarimetric data; in general, their function is to analyze a set of observed Stokes profiles, and infer the physical properties of the line-formation region in which the Stokes profiles were formed. For the SOLIS/VSM 6302v pipeline, the inversion is based on a Milne-Eddington model atmosphere, optimized to reproduce the observed Stokes profiles of both Fe I lines at 6301.5 and 6302.5 Angstroms . This document provides a detailed overview of the SOLIS/VSM remix of the VFISV (Very Fast Inversion of the Stokes Vector) inversion code, as it is implemented in the SOLIS/VSM pipeline environment.