We conducted a study on the X-ray polarisation properties of MCG-5-23-16 by analysing long-term monitoring data from NuSTAR jointly with IXPE observations made in May and November 2022. The re-analysis of IXPE data gives model-dependent polarisation degree, PD (%) = $1.08\pm0.66$ in the energy band 2–8 keV, which agrees with previous studies within error bars. The model-independent analysis of PD poses an upper limit of $\leq3.8$ ($1\sigma$ level) for the same energy band. The observed upper limit of PD, along with broadband spectral analysis (2–79 keV) using an accretion-ejection based model, allowed us to derive the corona geometry (i.e. radius and height) and the accretion disc inclination ($\sim33^\circ$). Additional NuSTAR observations were also analysed to gain insights into the accretion flow properties of the source and to estimate the expected polarisation during those epochs with PD $\sim 4.3\%$. The radius and height of the corona varies between $28.2\pm3.1 - 39.8\pm4.6$ r$_s$ and $14.3\pm1.7-21.4\pm1.9$ r$_s$ respectively, with a mass outflow rate from the corona measuring $0.14\pm0.03-0.2\pm0.03$ Eddington rate ($\dot m_{\mathrm{Edd}}$). The estimated PD values were nearly constant up to a certain radial distance and height of the corona and then decreased for increasing corona geometry. The spectral analysis further provided an estimate for the mass of the central black hole $\sim2\times 10^7$ M$_\odot$ and the velocity of the outflowing gas $\sim0.16-0.19c$. A comparative broadband spectral study using reflection-based models estimates the disc inclination between $\sim 31^\circ\pm8^\circ-45^\circ\pm7^\circ$, and yields an expected PD of 3.4–6.0%. We also found a weak reflection fraction and a less ionised distant reflecting medium. The expected PD measured using accretion-ejection and reflection models is less compared to the expected PD measured for a given disc inclination of $45^\circ$. Our modelling of the disc-corona-outflows and polarisation connection can be extended and validated with data from the recently launched XPoSat, India’s first X-ray Polarimeter Satellite, offering potential applications to other sources.

The central parsec of AGN is a key region for the launching of winds, and near-infrared interferometry is a unique tool for its study. With GRAVITY at the VLT interferometer, we can now spatially resolve not just the hot dust continuum on milliarcsecond ‘torus’ scales through imaging but also the broad-line region (BLR) on microarcsecond scales through spectro-astrometry. We have mapped the kinematics of the BLR in seven nearby AGN, measured sizes of the hot dust for seventeen AGN, and reconstructed dust images for two AGN. BLR kinematics has allowed us to measure the BLR size and supermassive black hole mass independent of reverberation mapping. The ongoing GRAVITY+ upgrade will greatly enhance the sensitivity and sky coverage of GRAVITY, and first results demonstrate its power for AGN science at z∼2 and beyond.

The mass accretion rate determines the black hole accretion mode and the corresponding efficiency of active galactic nuclei (AGNs) feedback. In large-scale simulations studying galaxy formation and evolution, the Bondi radius can be at most marginally resolved. In these simulations, the Bondi accretion formula is always used to estimate the black hole accretion rate. The Bondi solution can not represent the real accretion process. We perform 77 simulations with varying density and temperature at Bondi radius. We find a formula to calculate the black hole accretion rate based on gas density and temperature at Bondi radius. We find that the formula can accurately predict the luminosity of observed low-luminosity AGNs. This formula can be used in sub-grid models in large-scale simulations with AGNs feedback.

The galaxy Mrk 590 is one of the few known ‘changing-look’ Active Galactic Nuclei (AGN) to have transitioned between states twice, having just increased its flux after a period of ˜10 years of low activity. In addition to the increase in flux, the optical broad emission lines have reappeared but show a different profile than what was observed before they disappeared. The gas motions in the host galaxy of this changing-look AGN show outflows and dynamical structures able to drive gas to the nucleus, suggesting an interplay between inflow and outflow in the centre of the galaxy.

In this work, we study the optical properties of 58 CSS/GPS radio sources selected from the literature in order to determine the impact of the radio-jet in the circumnuclear environment of these objects. We obtained optical spectra for all sources from SDSS-DR12 and performed a stellar population synthesis using the Starlight code. Our results indicate that the sample is dominated by intermediate to old stellar populations and there is no strong correlation between optical and radio properties of these sources.

We have analyzed Chandra/High Energy Transmission Grating spectra of the X-ray emission line gas in the Seyfert galaxy NGC 4151. The zeroth-order spectral images show extended H- and He-like O and Ne, up to a distance r ˜ 200 pc from the nucleus. Using the 1st-order spectra, we measure an average line velocity ˜230 km s–1, suggesting significant outflow of X-ray gas. We generated Cloudy photoionization models to fit the 1st-order spectra; the fit required three distinct emission-line components. To estimate the total mass of ionized gas (M) and the mass outflow rates, we applied the model parameters to fit the zeroth-order emission-line profiles of Ne IX and Ne X. We determined an M ≍ 5.4 × 105 Mʘ. Assuming the same kinematic profile as that for the [O III] gas, derived from our analysis of Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra, the peak X-ray mass outflow rate is approximately 1.8 Mʘ yr–1, at r ˜ 150 pc. The total mass and mass outflow rates are similar to those determined using [O III], implying that the X-ray gas is a major outflow component. However, unlike the optical outflows, the X-ray emitting mass outflow rate does not drop off at r > 100pc, which suggests that it may have a greater impact on the host galaxy.

Jets often display bends and knots at which the flows change character. Extreme distortions have implications for the nature of jet flows and their interactions. We present the results of three radio mapping campaigns. The distortion of 3CRR radio galaxy NGC 7385 is caused by a collision with a foreground magnetised gas cloud which causes Faraday rotation and free-free absorption, and is triggered into star formation. For NGC 6109 the distortion is more extreme, creating a ring-shaped structure, but no deflector can be identified in cold or hot gas. Similar distortions in NGC 7016 are apparently associated with an X-ray gas cavity, and the adjacent NGC 7018 shows filaments drawn out beyond 100 kpc. Encounters with substructures in low-density, magnetised, intergalactic gas are likely causes of many of these features.

Radio galaxies of intermediate power dominate the radio-power injection in the Universe as a whole, due to the break in the radio luminosity function, and so are of special interest. The population spans FR I, FR II, and hybrid morphologies, resides in a full range of environmental richness, and sources of all ages are amenable to study. We describe structures and interactions, with emphasis on sources with deep high-resolution Chandra X-ray data. As compared with low-power sources there is evidence that the physics changes, and the work done in driving shocks can exceed that in evacuating cavities. A range of morphologies and phenomena is identified.

We present a search for OH maser emission in galaxies hosting H2O masers with the 100-m Effelsberg radio telescope and the Green Bank Telescope (GBT). This survey is aimed at investigating the apparent rarity and/or possible mutual exclusion of megamaser emission from OH and H2O in the same galaxy. Our study establishes new and better upper limits on the OH maser luminosity. Our work duplicates the number of H2O masers searched for OH emission. No new maser detections have been found. OH absorption, both in the 1667 and 1665 MHz transitions, is instead detected in two galaxies of the sample, IC342 and NGG5793.

The Seyfert galaxy MCG–6-30-15 has recently been observed in the infrared using SINFONI on the VLT, reaching a very high spatial resolution of 0.1 arcsec. This allowed us for the first time to detect a stellar kinematically decoupled core in the inner r < 125 pc of the galaxy. Here we summarise the main theories for the formation of the decoupled core and the implications on the study of this galaxy.

Variability is a successful technique used to identify active galactic nuclei in both ground and space-based galaxy surveys. Optical variability surveys using HST have uncovered a number of AGN in deep extragalactic fields extending to z ~ 3 and probing intrinsically faint sources. Mid-IR variability surveys using Spitzer have identified a significant number of AGN and are particularly sensitive to obscured sources. Many variability-detected AGN are not strong X-ray sources or lack the characteristic colors of AGN and would thus be unidentified using other selection techniques. In this conference proceedings, I discuss the nature of the variable sources and their host galaxies identified in deep extragalactic optical and mid-IR surveys.

We present preliminary results on fitting of SEDs to 142 z < 1 quasars selected in the mid-infrared. Our quasar selection finds objects ranging in extinction from highly obscured, type-2 quasars, through more lightly reddened type-1 quasars and normal type-1s. We find a weak tendency for the objects with the highest far-infrared emission to be obscured quasars, but no bulk systematic offset between the far-infrared properties of dusty and normal quasars as might be expected in the most naive evolutionary schemes. The hosts of the type-2 quasars have stellar masses comparable to those of radio galaxies at similar redshifts. Many of the type-1s, and possibly a one of the type-2s require a very hot dust component in addition to the normal torus emission.

Active galactic nuclei can be identified in deep HST surveys using different selection techniques and multiwavelength data. We aim to produce a complete sample of AGN in the GOODS South and North fields by combining X-ray, optical and mid-IR selection criteria, including galaxies displaying nuclear optical variability.

We observed the H2O maser at the nucleus of the Seyfert 2, IC 2560, using the VLBA and the phased VLA. The systemic, red-shifted and blue-shifted maser features and a continuum component have been detected. We propose a maser disk in the nuclear region. The systemic and red-shifted features are emitted from a nearly edge-on disk with the position angle of PA = −47°. The thickness is 2H < 0.025 pc. The binding mass is 3.5 × 106M⊙. Assuming the Keplerian rotation, the radii at the disk are r = 0.087-0.335 pc and the rotation velocities are 213–418 km s−1. The mean density within the inner radius is 1.3 × 109M⊙ pc−3, suggesting a massive black hole at the center. A continuum component is considered as a jet ejected from the nucleus, with an angle of 70° from the disk. The blue-shifted maser feature is located on the continuum component, being interpreted to be a ‘jet maser’.