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تسجيل مستخدم جديدA 98% spectroscopically complete sample of the most powerful equatorial radio sources at 408 MHz
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P. N. Best
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A new sample of very powerful radio galaxies is defined from the Molonglo Reference Catalogue, according to the criteria S (408 MHz) > 5 Jy, -30 < Dec < 10 degrees, |b| > 10 degrees. The sample is selected to have similar properties to the northern 3CR revised sample, and to be visible to a combination of existing northern telescopes such as the Very Large Array radio interferometer and large southern hemisphere telescope facilities. The sample contains 178 sources, of which spectroscopic redshifts are available in the literature for 128. For the remaining 50 sources, new radio imaging, optical imaging and spectroscopic observations are presented to identify the host galaxies and determine their redshifts. With these new observations the total sample is 100% optically identified and redshifts are available for 174 (98%) of the sources. The sample consists of one starburst galaxy, one Seyfert galaxy, 127 radio galaxies and 49 quasars. Basic properties of the sample, such as the distributions of the quasar and radio galaxy populations in redshift and their locations on the radio power versus linear size (P-D) diagram, show no significant differences from the revised 3CR sample. The equatorial location and the high spectroscopic completeness of this sample make it a valuable resource for detailed studies of the nature and environments of these important objects with the new generation of southern hemisphere telescopes.
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A new sample of very powerful radio sources, defined from the Molonglo Reference Catalogue, was recently compiled by Best, Rottgering and Lehnert (1999). These authors provided redshifts for 174 of the 178 objects in the sample, making the sample 98%
spectroscopically complete. Here, redshifts for three of the remaining galaxies are presented, confirming the optical identifications and raising the spectroscopic completeness of the sample to 99.5%; only 1059-010 (3C249) is currently without redshift.
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