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The narrow-line Seyfert 1 galaxy IRAS17020+4544 is one of the few sources where both an X-ray ultra-fast outflow and a molecular outflow were observed to be consistent with energy conservation. However, IRAS17020+4544 is less massive and has a much more modest active galactic nucleus (AGN) luminosity than the other examples. Using recent CO(1-0) observations with the NOrthern Extended Millimeter Array (NOEMA), we characterised the molecular gas content of the host galaxy for the first time. We found that the molecular gas is distributed into an apparent central disc of 1.1x10^9 Msun, and a northern extension located up to 8 kpc from the centre with a molecular gas mass M_H2~10^8 Msun. The molecular gas mass and the CO dynamics in the northern extension reveal that IRAS 17020+4544 is not a standard spiral galaxy, instead it is interacting with a dwarf object corresponding to the northern extension. This interaction possibly triggers the high accretion rate onto the super massive black hole. Within the main galaxy, which hosts the AGN, a simple analytical model predicts that the molecular gas may lie in a ring, with less molecular gas in the nuclear region. Such distribution may be the result of the AGN activity which removes or photodissociates the molecular gas in the nuclear region (AGN feedback). Finally, we have detected a molecular outflow of mass M_H2=(0.7-1.2)x10^7 Msun in projection at the location of the northern galaxy, with a similar velocity to that of the massive outflow reported in previous millimeter data obtained by the Large Millimeter Telescope., Comment: Published in MNRAS, Volume 501, Issue 1, Pages 219-228

Until recently, relativistic jets were ubiquitously found to be launched from giant elliptical galaxies. However, the detection by the Fermi-LAT of gamma-ray emission from radio-loud narrow-line Seyfert 1 (RL-NLSy1) galaxies raised doubts on this relation. Here, we morphologically characterize a sample of 29 RL-NLSy1s (including 12 gamma-ray emitters, gamma-NLSy1s) in order to find clues on the conditions needed by AGN to produce relativistic jets. We use deep near-infrared images from the Nordic Optical Telescope and the ESO VLT to analyze the surface brightness distribution of the galaxies in the sample. We detected 72% of the hosts (24% classified as gamma-NLSy1s). Although we cannot rule out that some RL-NLSy1s are hosted by dispersion supported systems, our findings strongly indicate that RL-NLSy1s hosts are preferentially disc galaxies. 52% of the resolved hosts (77% non-gamma-emitters and 20% gamma-emitters) show bars with morphological properties (long and weak) consistent with models that promote gas inflows, which might trigger nuclear activity. The extremely red bulges of the gamma-NLSy1s, and features that suggest minor mergers in 75% of their hosts might hint to the necessary conditions for gamma-rays to be produced. Among the features that suggest mergers in our sample, we find 6 galaxies that show offset stellar bulges with respect to their AGN. When we plot the nuclear versus the bulge magnitude, RL-NLSy1s locate in the low-luminosity end of flat-spectrum radio quasars (FSRQs), suggesting a similar accretion mode between these two AGN types., Comment: 17 pages, 9 figures, 3 tables

We report on the coexistence of powerful gas outflows observed in millimeter and X-ray data of the Radio-Loud Narrow Line Seyfert 1 Galaxy IRAS 17020+4544. Thanks to the large collecting power of the Large Millimeter Telescope, a prominent line arising from the 12CO(1-0) transition was revealed in recent observations of this source. The complex profile is composed by a narrow double-peak line and a broad wing. While the double-peak structure may be arising in a disk of molecular material, the broad wing is interpreted as the signature of a massive outflow of molecular gas with an approximate bulk velocity of -660 km/s. This molecular wind is likely associated to a multi-component X-ray Ultra-Fast Outflow with velocities reaching up to ~0.1c and column densities in the range 10^{21-23.9} cm^-2 that was reported in the source prior to the LMT observations. The momentum load estimated in the two gas phases indicates that within the observational uncertainties the outflow is consistent with being propagating through the galaxy and sweeping up the gas while conserving its energy. This scenario, which has been often postulated as a viable mechanism of how AGN feedback takes place, has so far been observed only in ULIRGs sources. IRAS 17020+4544 with bolometric and infrared luminosity respectively of 5X10^{44} erg/s and 1.05X10^{11} L_sun appears to be an example of AGN feedback in a NLSy1 Galaxy (a low power AGN). New proprietary multi-wavelength data recently obtained on this source will allow us to corroborate the proposed hypothesis., Comment: Accepted for publication on ApJ Letters, 9 pages, 4 figures

The jet activity of Active Galactic Nuclei (AGN), and its interaction with the interstellar medium (ISM), may play a pivotal role in the processes which regulate the growth and star formation of its host galaxy. Observational evidence which pinpoints the conditions of such interaction is paramount to unveil the physical processes involved. We report on the discovery of extended emission line regions exhibiting an S-shaped morphology along the optical jet of the radio-loud AGN $\text{PKS}\,0521-365$ ($z=0.055$), by using long-slit spectroscopic observations obtained with FORS2 on VLT. The velocity pattern derived from the $\text{[O II]}\,\lambda 3727\,\AA,\, \text{H}\beta\, \lambda 4861\,\AA\,$ and [O III] $\lambda\lambda4959,5007\,\AA\,$ emission lines is well-fitted by a sinusoidal function of the form: $v(r)=\alpha r^{1/2}sin(\beta r^{1/2}+\gamma)$, suggesting helicoidal motions along the jet up to distances of $20\,\text{kpc}$. We estimate a lower limit for the mass of the outflowing ionized gas along the jet of $\sim$10$^4\,M_\odot$. Helical magnetic fields and jet precession have been proposed to explain helicoidal paths along the jet at pc scales; nevertheless, it is not clear yet whether these hypotheses may hold at kpc scales., Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letters

We present near--infrared (NIR) imaging of FBQS J164442.5+261913, one of the few $\gamma$--ray emitting Narrow Line Seyfert 1 ($\gamma-$NLSy1) galaxies detected at high significance level by $Fermi$--LAT. This study is the first morphological analysis performed of this source and the third performed of this class of objects. Conducting a detailed two--dimensional modeling of its surface brightness distribution and analysing its $J-K_s$ colour gradients, we find that FBQS J164442.5+261913 is statistically most likely hosted by a barred lenticular galaxy (SB0). We find evidence that the bulge in the host galaxy of FBQS J164442.5+261913 is not classical but pseudo, against the paradigm of powerful relativistic jets exclusively launched by giant ellipticals. Our analysis, also reveal the presence of a ring with diameter equalling the bar length ($r_{bar} = 8.13\ \textrm{kpc}\pm 0.25$), whose origin might be a combination of bar--driven gas rearrangement and minor mergers, as revealed by the apparent merger remnant in the $J$--band image. In general, our results suggest that the prominent bar in the host galaxy of FBQS J164442.5+261913 has mostly contributed to its overall morphology driving a strong secular evolution, which plays a crucial role in the onset of the nuclear activity and the growth of the massive bulge. Minor mergers, in conjunction, are likely to provide the necessary fresh supply of gas to the central regions of the host galaxy., Comment: 12 pages, 9 figures, 1 table

Supermassive black holes launching plasma jets at close to speed of light, producing gamma-rays, have ubiquitously been found to be hosted by massive elliptical galaxies. Since elliptical galaxies are generally believed to be built through galaxy mergers, active galactic nuclei (AGN) launching relativistic jets are associated to the latest stages of galaxy evolution. We have discovered a pseudo-bulge morphology in the host galaxy of the gamma-ray AGN PKS 2004-447. This is the first gamma-ray emitter radio loud AGN found to be launched from a system where both black hole and host galaxy have been actively growing via secular processes. This is evidence for an alternative black hole-galaxy co-evolutionary path to develop powerful relativistic jets that is not merger-driven., Comment: 20 pages, 4 figures. Astrophysical Journal, accepted

We present deep Near-infrared (NIR) images of a sample of 19 intermediate-redshift ($0.310^{27}$ WHz$^{-1}$), previously classified as flat-spectrum radio quasars. We also compile host galaxy and nuclear magnitudes for blazars from literature. The combined sample (this work and compilation) contains 100 radio-loud AGN with host galaxy detections and a broad range of radio luminosities $L_{1.4GHz} \sim 10^{23.7} - 10^{28.3}$~WHz$^{-1}$, allowing us to divide our sample into high-luminosity blazars (HLBs) and low-luminosity blazars (LLBs). The host galaxies of our sample are bright and seem to follow the $\mu_{e}$-$R_{eff}$ relation for ellipticals and bulges. The two populations of blazars show different behaviours in the \mnuc - \mbulge plane, where a statistically significant correlation is observed for HLBs. Although it may be affected by selection effects, this correlation suggests a close coupling between the accretion mode of the central supermassive black hole and its host galaxy, that could be interpreted in terms of AGN feedback. Our findings are consistent with semi--analytical models where low--luminosity AGN emit the bulk of their energy in the form of radio jets, producing a strong feedback mechanism, and high--luminosity AGN are affected by galaxy mergers and interactions, which provide a common supply of cold gas to feed both nuclear activity and star formation episodes., Comment: Final version to appear in MNRAS

We explore the connection between the black hole mass and its relativistic jet for a sample of radio-loud AGN (z < 1), in which the relativistic jet parameters are well estimated by means of long term monitoring with the 14m Mets\"ahovi millimeter wave telescope and the Very Long Base-line Array (VLBA). NIR host galaxy images taken with the NOTCam on the Nordic Optical Telescope (NOT) and retrieved from the 2MASS all-sky survey allowed us to perform a detailed surface brightness decomposition of the host galaxies in our sample and to estimate reliable black hole masses via their bulge luminosities. We present early results on the correlations between black hole mass and the relativistic jet parameters. Our preliminary results suggest that the more massive the black hole is, the faster and the more luminous jet it produces.

We present optical and near infrared (NIR) imaging data of the radio-loud Narrow-line Seyfert 1 galaxy 1H 0323+342, which shows intense and variable gamma-ray activity discovered by the Fermi satellite with the Large Area Telescope. NIR and optical images are used to investigate the structural properties of the host galaxy of 1H 0323+342; this together with optical spectroscopy allowed us to examine its black hole mass. Based on the 2D multiwavelength surface brightness modeling, we find that, statistically, the best model fit is a combination of a nuclear component and a S\'ersic profile (n~2.8). However, the presence of a disc component (with a small bulge n~1.2) remains also a possibility and cannot be ruled out with the present data. Although at first glance a spiral-arm like structure is revealed in our images, a 2D Fourier analysis of the imagery suggests that such structure corresponds to an asymmetric ring, likely associated to a recent violent dynamical interaction. We discuss our results on the context of relativistic jets production and galaxy evolution., Comment: 14 pages, 6 figures, accepted for publication in ApJ