HIGH-RESOLUTION RADIO OBSERVATIONS OF THE CFA SEYFERT SAMPLE .1. THE OBSERVATIONS

We present high-resolution VLA maps of the CfA Seyfert galaxies of Huc hra & Burg. Because this sample is relatively free from biases and sel ection effects it is particularly well suited for comparisons of the r adio properties of type 1 and 2 Seyferts. However, previous radio obse rvations of the sample have lacked sufficient angular resolution to gi ve useful structural information. The 0.25-arcsec resolution of A-conf iguration at 8.4 GHz has enabled us to determine the radio morphology of the sample on subarcsecond scales for the first time, and complemen tary observations in C-configuration have allowed measurements of the total radio luminosity of the active nucleus, free from contamination by disc emission. The sources used for phase calibration of the data w ere carefully selected so that the positional information in our maps is accurate to within 50 mas. In this paper we describe the data and d iscuss the advantages and limitations of the present sample. The natur e and origin of the radio emission and the statistical properties of t he Seyfert type 1 and 2 galaxies in the sample will be discussed in tw o subsequent papers.