Wavelet power spectra of the M83 images, obtained with the isotropic 2D Mexican Hat from bottom to top: H II, H I, CO, total neutral gas, warm dust, cold dust, total synchrotron intensity at λ6 cm, polarized intensity at λ6 cm, polarized intensity at λ13 cm, and a weighted sum of the polarized intensities at λ6 cm and λ13 cm defined in Sect. 2.3. All the spectra have been multiplied by various factors chosen to avoid overcrowding of the curves: what matters is the relative distribution of the wavelet spectral power between scales in a given image rather than the relative power in different images. Error bars are evaluated from the variance of the sample mean.