The radio structure of the narrow-line Seyfert 1 Mrk 783 with VLBA and e-MERLIN




Congiu E, Kharb P, Tarchi A, Berton M, Caccianiga A, Chen S, Crepaldi L, Di Mille F, Järvelä E, Jarvis M E, La Mura G, Vietri A

2020

 Monthly Notices of the Royal Astronomical Society

499

3

3149

3157

9

0035-8711

1365-2966

DOIhttps://doi.org/10.1093/mnras/staa3024

https://research.utu.fi/converis/portal/detail/Publication/50366673



In this paper, we present the analysis of new radio and optical observations of the narrow-line Seyfert 1 galaxy Mrk 783. $1.6\, \mathrm{GHz}$ observations performed with the e-MERLIN interferometer confirm the presence of the diffuse emission previously observed. The Very Long Baseline Array (VLBA) also detects the nuclear source both at $1.6\, \mathrm{GHz}$ (L band) and $5\, \mathrm{GHz}$ (C band). While the L-band image shows only an unresolved core, the C-band image shows the presence of a partially resolved structure at a position angle of 60. The brightness temperature of the emission in both bands ( ${\gt}10^6\, \mathrm{K}$ ) suggests that it is a pc-scale jet produced by the active galactic nucleus. The relatively steep VLBA spectral index (αVLBA = 0.63 ± 0.03) is consistent with the presence of optically thin emission on milliarcsecond scales. Finally, we investigated two possible scenarios that can result in the misalignment between the kpc and pc-scale radio structure detected in the galaxy. We also analysed the optical morphology of the galaxy, which suggests that Mrk 783 underwent a merging in relatively recent times....

Last updated on 26/11/2024 02:13:12 PM