Spectacular 240 kpc double-sided relativistic jets in a spiral- hosted narrow-line Seyfert 1 galaxy
Narrow-line Seyfert 1 (NLS1) galaxies are a sub-class of active galactic nuclei (AGN). Their narrow permitted lines can be explained with a low gas velocity around a low-mass black hole (BH). Some authors, instead, proposed that the low BH mass is due to an inclination effect. Studying host galaxy morphologies can be useful to disentangle these two scenarios. Moreover, NLS1s have demonstrated that the presence of radio jets in an AGN is governed by other factors than those previously believed. To this aim, I worked on radio and NIR/optical properties of a remarkable NLS1, J0354-1340. From the VLA observations, I found that the source shows very extended radio jets, the largest found to date in an NLS1. The high spectral index of the extended emission is due to the interaction between the extended jets and the ICM, which re-accelerates the electrons in the lobe. By means of photometric decomposition and colour maps, I found this NLS1 hosted by a disc-like galaxy, probably with pseudobulges. My results confirm that powerful jets can also be launched and sustained by less massive BHs in spiral galaxies dominated by secular processes and not only by elliptical galaxies hosting the massive BHs and experiencing merger events.