Monthly Notices of the Royal Astronomical Society · 1987 · 33 citations · 0 references
Natural SciencesAstronomyPhysicsAstrophysicsExtragalactic AstronomyRadio AstronomyExtragalactic Infrared AstronomyNear-infrared AstronomyExtragalactic Source CatalogsInfrared Spectroscopy Of GalaxiesPoint Source CatalogsRadio Telescope SystemsSeyfert GalaxiesSpectral Flux Density
A sensitive search for powerful OH masers in external galaxies has been carried out with the Jodrell Bank Mk1A radio telescope and a new Acousto–Optical Spectrometer. Candidate sources were selected from the IRAS Point Source Catalog on the basis of their infrared colours and were searched for OH mainline emission at 18-cm wavelength, with a velocity coverage of 17 000 km s–1 and a resolution of 40 km s–1. A typical detection level of 14 mJy was achieved. One new source, III Zw 35, was discovered. This source has an exceptionally large ratio of OH to infrared flux density. The search has also revealed high-velocity wings in the OH emission from the two Seyfert galaxies, Mrk 231 and 273. The velocity widths are too high to be accounted for by galactic rotation, which suggests that the molecular gas may be closely associated with the Seyfert nuclei.