Polarization properties of NGC 4565 derived from RM synthesis. Left panel: map of the polarized intensity. Right panel: RM map, with the Galactic foreground contribution subtracted. The intrinsic magnetic field orientations, corrected for Faraday rotation, are shown as black lines. The RM values and field lines are blanked for polarized intensities below 5σ, where σ = 3.12 μJy beam⁻¹. In both panels, total intensity contours from Figure 1(b) at levels of 3, 24, and 192σ are overlaid to outline the galaxy’s structure. The 15″ synthesized beam is displayed in the bottom-right corner.