High resolution interferometry of the QSO 1422+202

¹ Centre for Imaging Technologies, Halmstad University, S-301 18 Halmstad, Sweden
² Istituto di Radioastronomia del C.N.R., Via P. Gobetti, I-40129 Bologna, Italy

Send offprint request to: F. Mantovani

Received: 10 November 1996
Accepted: 29 January 1997

Abstract

We present VLA A-array observations at 8.4 and 15 GHz and European VLBI Network (EVN) observations at 1.6 GHz of the radio source 1422+202. It is suggested that 1422+202 is a Medium-size Object in the evolutionary sequence from Compact Steep-spectrum Sources to larger sized radio sources. The VLBI data were analysed with the phase referencing technique and we show that the EVN can work as a phase stable instrument for separations between the calibrator source and the target source up to ∼ 10°. With the VLA and VLBI observations we investigate some of the issues about the nucleus of 1422+202 and we discuss the possible cause for the low frequency variability detected while monitoring the source.