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arXiv · 2009.13529

The Radio Structure of the Narrow-Line Seyfert 1 Mrk 783 with VLBA and e-MERLIN

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

In this paper, we present the analysis of new radio and optical observations of the narrow-line Seyfert 1 galaxy Mrk 783. 1.6 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 GHz (L-Band) and 5 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 ($>10^6$ K) suggests that it is a pc-scale jet produced by the AGN. The relatively steep VLBA spectral index ($α_{VLBA} = 0.63\pm0.03$) 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.

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E. Congiu, P. Kharb, A. Tarchi, M. Berton, A. Caccianiga, S. Chen, L. Crepaldi, F. Di Mille, E. Järvelä, M. E. Jarvis, G. La Mura, A. Vietri. 2020-09-28. The Radio Structure of the Narrow-Line Seyfert 1 Mrk 783 with VLBA and e-MERLIN. https://doi.org/10.1093/mnras%2Fstaa3024

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