IRAS 23389+0300

Description

The system is either a pre-galaxy merger or a close binary, with two nuclei separated by about 5.2 kiloparsecs. The northern galaxy is compact, highly reddened, and the brighter of the two in radio wavelengths; a short tidal feature south of both galaxies suggests they may be on the verge of merging. The northern nucleus is active and radio-loud, hosting a gigahertz peaked spectrum source with a radio core, extended emission, and two slightly resolved radio lobes 830 parsecs apart. Optical and near-infrared imaging place the lobes near the northern nucleus, and the radio spectrum has a spectral age of 0.68 million years. Warm outflows are detected in the northern galaxy's nuclear regions, with oxygen and iodine emission lines stronger than doubly ionized oxygen lines. The outflow has two components: a narrow one and a broad one redshifted by about 47 ± 13 km/s, with a high-density outflow mass rate of 10.4+11.1−5.1 M☉ per year and a kinetic power of 0.63 percent; the outflow may be driven by the radio jet. The total star formation rate of the system is 100 ± 40 M☉ per year, and modelling indicates very young stellar populations toward the north.