Radio properties of the Shapley concentration .1. The Abell cluster A3556

We have imaged the portion of the Shapley Concentration core surrounding the cluster A3556 at wavelengths of 36 cm with the Molonglo Observatory Synthesis Telescope (MOST), and at 22 and 13 cm with the Australia Telescope Compact Array (ATCA). We have defined a radio sample of 112 radio sources at 22 cm. Cross-correlation with optical catalogues allowed the identification of 29 radio sources, nine of which belong to A3556. The radio and optical properties of A3556 have been studied in detail, Two extended radio sources are associated with cluster members, i.e. a narrow-angle-tail source located at a projected distance of 0.06R(A) from the centre, possibly in the late stages of its existence, and a wide-angle-tail source at the periphery of the cluster. We also performed a statistical analysis of the cluster properties, The optical luminosity function shows that the cluster has an excess of bright optical galaxies, In agreement with well-established results, we found that the probability of radio emission increases for brighter galaxies, Furthermore, our radio luminosity function and those obtained for elliptical galaxies located in different environments (poor groups and rich clusters) are very similar, implying that the peculiar dynamical state of A3556 has no influence on the radio emission properties of the cluster galaxies.