Radio and mid-infrared properties of the blazar J1419$-$0838

Abstract

The radio quasar NVSS J141922$-$083830 (J1419$-$0838) was initially classified as an uncategorised blazar-type object, following its detection in the $γ$-ray band with the Fermi space telescope. Later, using multi-waveband observations and modeling, its was found to be a flat-spectrum radio quasar (FSRQ). However, its radio emission has never been discussed in depth in the literature. Here we present a detailed analysis on the radio properties of J1419$-$0838 using archival interferometric imaging data at pc and kpc scales. We conclude that the flux density variations, the flat radio spectrum, the compact nature of the quasar structure at all scales, and the relativistic Doppler enhancement of the radio emission all support the previous classification as an FSRQ. We also investigated the short- and long-term mid-infrared (MIR) light curve of the quasar based on observations by the Wide-field Infrared Survey Explorer satellite, and found that there is significant variability on time-scales of days as well as years. Comparison of the MIR light curve to the times of previously reported $γ$-ray and optical flares shows no clear correlation between the events at different wavebands.