7 Concluding remarks

This paper presents new catalogues of source radio spectral index in the MCs. There is a total of 483 radio sources towards the LMC, 143 of which are classified for the first time. Also new catalogues of source radio spectral index in the SMC are presented with a total of 224 radio sources towards the SMC, 60 of which are classified here for the first time.

The radio spectral index $\alpha$ has been estimated for 422 sources in the field of the LMC and 162 towards the SMC. We have investigated the distribution of the spectral index over different types of sources and found that the spectral index cannot be the only criterion in distinguishing SNRs, Hii regions and background sources.

We have compared our radio catalogues with a range of catalogues from other wavelengths such as X-ray, UV, H$\alpha$, optical, IR and CO. Luminosity functions have been investigated for SNRs and Hii regions in both Clouds. We have checked the consistency of our background source number in the field of the MCs with published Log N - Log S counts.

In total, 209 discrete radio sources in the LMC and the 37 sources in the SMC are classified here to be either Hii regions or SNRs. We have plotted the positions of these intrinsic sources (Figs. 11 and 12) to investigate the structure of both Clouds. These sources are believed to be tracers for the possible spiral structure in galaxies and we found some indication of a spiral structure in the LMC with the centre somewhere in 30 Doradus. The source distributions throughout the SMC are grouped into two regions: the main-body and the eastern wing of the SMC.

Acknowledgements

We thank D. Meinert, D. Goddard, J. Lequeux and J. Caswell for considerable support and comments in manuscript.