Identifying compact symmetric objects in the southern sky

We present results of multifrequency polarimetric VLBA observations of 20 compact radio sources. The observations represent the northern and southern extensions of a large survey undertaken to identify compact symmetric objects (CSOs) observed in the northern sky. CSOs are young radio galaxies whose jet axes lie close to the plane of the sky and whose appearance is therefore not dominated by relativistic beaming effects. The small linear sizes of CSOs make them valuable for studies of both the evolution of radio galaxies and testing unified schemes for active galactic nuclei. In this paper we report on observations of 20 new CSO candidates discovered in the northern and southern extremities of the VLBA Calibrator Survey. We identify four new CSOs, and discard 12 core-jet sources. The remaining four sources remain candidates pending further investigation. We present continuum images at 5 and 15 GHz and, where relevant, images of the polarized flux density and spectral index distributions for the eight new CSOs and CSO candidates.