2014MNRAS.445.4507I

We present radio observations, made using the Very Large Array and the Green Bank Telescope, of two supernova remnants and four planetary nebulae. These objects are part of a larger sample of radio sources, discussed in a previous paper, a counterpart of the MIPSGAL 24-µm compact bubbles. For the two supernova remnants, we have combined the interferometric observations with single-dish data to obtain both a high resolution and a good sensitivity to extended structures. We discuss in detail the entire combination procedure adopted and the reliability of the resulting maps. For one supernova remnant, we pose a more stringent upper limit for the flux density of its undetected pulsar, and we also show prominent spectral index spatial variations, probably resulting either from inhomogeneities in the magnetic field and in its ejecta or from an interaction between the supernova shock and molecular clouds. We eventually use the 5-GHz maps of the four planetary nebulae to estimate their distances and their ionized masses.