B2 1141 + 37: a giant radio galaxy with remarkable radio and optical properties

Abstract

The radio galaxy B2 1141 + 37 is remarkable for both its radio and optical properties. The radio source has a double structure for which the ratio of the separation between the components to their dimension is exceptionally large. Moreover, our recent measurement of the redshift gives z = 0.115 giving a separation between the components of 1.0 Mpc. This makes 1141 + 37 one of the largest radio structures known. The optical identification which has been proposed is a tight chain of galaxies which are probably gravitationally bound. If this is the case, the radio galaxy must have some precession and/or rotation motion around the centre of mass of the group with important consequences on the structure and evolution of the radio source. We report here on the redshift measurement and on some VLA observations at 4.9 GHz.