Compact Radio Sources Apparently Associated with Extended Galactic Sources

Abstract

We report VLA radio observations of the 21 cm HI line toward two compact radio sources that could be associated with extended Galactic sources. In the case of the planetary nebula PHR 1735-333 we observed HI absorption against a non-thermal radio source recently discovered in the region, which was proposed to be physically associated with the planetary nebula. However, from the analysis of the HI absorption spectrum, we suggest a larger distance for this non-thermal source. In the case of the supernova remnant candidate SNR G3.8+0.3 we obtained HI absorption spectra towards it and towards a compact radio source located at its center. We conclude that SNR G3.8+0.3 is more distant than the compact radio source and that they are not physically associated.