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We present 1D cosmic ray transport models, numerically solving equations ofpure advection and diffusion for the electrons and calculating synchrotronemission spectra. We find that for exponential halo magnetic fielddistributions advection leads to approximately exponential radio continuumintensity profiles, whereas diffusion leads to profiles that can be betterapproximated by a Gaussian function. Accordingly, the vertical radio spectralprofiles for advection are approximately linear, whereas for diffusion they areof `parabolic' shape. We compare our models with deep ATCA observations of twoedge-on galaxies, NGC 7090 and 7462, at $\lambda\lambda$ 22 and 6 cm. Ourresult is that the cosmic ray transport in NGC 7090 is advection dominated with$V=150^{+80}_{-30}~\rm km\,s^{-1}$, and that the one in NGC 7462 is diffusiondominated with $D=3.0\pm 1.0 \times 10^{28}E_{\rm GeV}^{0.5}~\rm cm^2\,s^{-1}$.NGC 7090 has both a thin and thick radio disc with respective magnetic fieldscale heights of $h_{\rm B1}=0.8\pm 0.1$ kpc and $h_{\rm B2}=4.7\pm 1.0$ kpc.NGC 7462 has only a thick radio disc with $h_{\rm B2}=3.8\pm 1.0$ kpc. In bothgalaxies, the magnetic field scale heights are significantly smaller than whatestimates from energy equipartition would suggest. A non-negligible fraction ofcosmic ray electrons can escape from NGC 7090, so that this galaxy is not anelectron calorimeter.

Advective and diffusive cosmic ray transport in galactic haloes