B0924 + 30 an unusual radio galaxy

Abstract

THE radio source B0924 + 30 (ref. 1) has been studied as part of a systematic survey of radio galaxies of relatively low (< 10⁴¹ erg s⁻¹) radio luminosity. The radio source is identified with a 14 mag elliptical galaxy with a redshift z = 0.0266 (refs 2 and 3). A 12-h observation of this radio source was made with the Westerbork Synthesis Radio Telescope⁴ at 1.4 GHz in September 1974, and Fig. 1 is a contour plot of the brightness distribution obtained. The resolution is 23″ in right ascension and 46″ in declination. The r.m.s. noise level in the map is 0.5 mJy. For a single 12-h observation the map is distorted by elliptical grating rings of semiaxis 10′×20′. The grating rings from many of the small diameter sources have been removed, but the distortion from the extended part of the radio galaxy remains and is the cause of the low level negative regions to the north and south of the galaxy. No correction for the primary beam attenuation, which reaches a factor of 2 at the edge of the map, has been applied. The position of the nucleus of the elliptical galaxy is RA = 09 h 24 min 55.1 s, dec. = 30°12′15″, and is indicated by the + in Fig. 1.