Power spectra referring to the MD (green) and GD (red) synchrotron maps shown in Fig. 1, as well as the power spectrum calculated from the difference between them (blue), defined in the frequency channel centered at 1115 MHz and with a bandwidth of δν ∼ 9.33 MHz (30 channels configuration). The maps were convolved with a FWHM = 40 arcmin beam. The observed region corresponds to the area covered by BINGO with the apodized Galactic mask defined in Sect. 3.2.