Schematic picture of the Galactic arms as viewed from the north Galactic pole. Black spiral curves show the axes of the best-fit spiral magnetic arms of our model. The intensity of the color indicates the magnetic field strength in the Galactic plane ɀ = 0. The blue (orange) colored regions correspond to the magnetic field directed inward/clockwise (outward/counter-clockwise) as marked by the black arrows at the bottom of the plot. Black dot marks the Galactic center while an ellipse represents the Galactic bar. Red star marks the position of the Sun. Grey regions show the spiral arms as deduced from Gαiα observations. The pitch angle in the solar vicinity is 20°.