Disentangling the Faraday rotation sky

We present the first full sky map of the line-of-sight averaged Galactic magnetic field. Within this map, we find LoS parallel and LoS-averaged magnetic field strengths of up to 4uG, with an all-sky root-mean-square of 1.1uG, which is consistent with previous local measurements and global magnetic field models. Additionally, we produce a detailed electron dispersion measure map, which agrees with already existing parametric models at high latitudes, but suffers from systematic effects in the disk.

Further analysis of our results with regard to the 3D structure of n_e_ reveals that it follows a Kolmogorov-type turbulence for most of the sky. From the reconstructed dispersion measure and emission measure maps we construct several tracers of variability of n_e_ along the LoS. This work demonstrates the power of consistent joint statistical analysis including multiple data sets and physical quantities and defines a roadmap towards a full three-dimensional joint reconstruction of the Galactic magnetic field and the ionized ISM.