A Radio Survey of the Southern Milky Way at a Frequency of 1440 Mc/s. I. The Isophotes and the Discrete Sources

Abstract

The 1440 Mc/s isophotes of the Southern Milky Way are presented which were obtained with an aerial beam 50' of arc at half-power points. The positions and intensities of the discrete sources resolved from the background emission are listed together with their spectral characteristics determined by comparison with the 85 -5 Mc/s Mills-Cross survey. Of 74 sources, 54 are found to have spectral indices consistent with the assumption that they radiate thermally_ Twelve new identifications of these thermal radio sources haye been made with emission nebulae by comparison with the Stromlo Atlas of Hex emission. The remaining twenty sources have nonthermal spectral indices and no new optical identifications have been made_ The continuum background emission from the galactic disk is discussed in a second paper.