Anna Trindade Falcão

The Chandra X-ray Observatory has revealed that kiloparsec-scale extended X-ray emission is commonly associated with heavily absorbed ( log ( N H /cm ⁻² ) > 23) active galactic nuclei (AGNs) in the local Universe. We present a homogeneous spatially resolved spectral analysis of a sample of nearby obscured AGN observed with deep (>100 ks) Chandra/ACIS exposures and all associated with extranuclear extended emission. Exploiting the subarcsecond resolution of Chandra, we separate unresolved nuclear emission from physically distinct extended regions and model their spectra using photoionized and thermal plasma components. The extended emission is spectrally complex, requiring a combination of photoionized and collisionally ionized components in most regions. The spectral parameters exhibit systematic radial variations, with nuclear regions typically hosting higher-column and higher-ionization components, while extended regions span similarly broad but overlapping ranges without a simple monotonic radial progression. Hard (>3 keV) X-ray emission in excess of nuclear point-spread function spillover is detected in 19/20 sources, while extended Fe K α emission is observed in 12/20 systems. These results establish a uniform baseline for the X-ray properties of heavily obscured AGN and provide constraints on the geometry and physical conditions of AGN-driven feedback in the local Universe.

The growth of galaxies and their central supermassive black holes is closely connected, yet the net effect of active galactic nucleus (AGN) feedback on host-galaxy star formation remains uncertain. AGN may enhance, suppress, or have little measurable impact on star formation, but distinguishing among these outcomes requires separating star formation and AGN photoionization from shock excitation, which is expected in AGN-driven outflows but has been difficult to isolate. Here we apply a recently developed theoretical three-dimensional diagnostic diagram, designed to separate star formation, AGN, and shock excitation, to Very Large Telescope/MUSE integral field unit observations of nine nearby ( z < 0.026) Type 2 Seyfert galaxies. We find a common excitation pattern across the sample: star-forming rings or arcs at projected radii of r ∼ 0.8–6 kpc, AGN-photoionized bicones extending to kiloparsec scales, central fast-shock-dominated regions that often extend perpendicular to the AGN bicone, and pure-shock-dominated regions surrounding the central fast shocks and appearing locally within the star-forming rings. Deep Chandra X-ray morphology independently supports this decomposition. The circumnuclear star-forming rings are consistent with bar-driven resonances, although positive AGN feedback may also contribute. The central fast shocks are broadly consistent with AGN jet–interstellar medium (ISM) interactions, while AGN wind–ISM interactions may also play an important role in galaxies with low-power jets. These results establish central shocks as a common feature of Seyfert galaxies and demonstrate the importance of accounting for shock excitation in AGN feedback studies.

We present a detailed, spatially resolved Veilleux and Osterbrock (VO) diagram analysis of ESO 137-G034, a Compton-thick active galactic nucleus (AGN), based on narrowband Hubble Space Telescope imaging in [O III ], [S II ], H α , and H β emission lines. The narrowband optical emission exhibits a biconical morphology and traces the diffuse X-ray emission observed with Chandra. We dissect the interstellar medium (ISM) into Seyfert-, LINER-, and H II -dominated regions with a resolution of ∼0 . ″ 1 (∼20 pc at z = 0.009). To visualize the fine spatial structure of the ISM excitation, we introduce a new parameter: the Seyfert/LINER Index (SLI), defined as the perpendicular distance of each point in the VO diagram from the Seyfert/LINER division line. SLI mapping reveals fine spatial structures in the ISM excitation especially in the Seyfert ionization bicones where the statistical significance of our data is higher. Most of the emission within the bicones is Seyfert-like, with SLI values consistent with regions of the VO diagram that can be modeled with AGN photoionization. In the northwest Seyfert cone three radial SLI peaks suggest episodic nuclear outbursts, with estimated timescales of a few 10 ³ yrs and 1000 km s ⁻¹ ) induced excitation. The northwest cone is surrounded by a smooth LINER “cocoon.” The LINER region in the southeast cone appears more irregular, with intercone LINER points likely shaped by both local ISM structure and shocks. Our findings highlight the complex interplay of different AGN feedback mechanisms in the ISM.

Accretion onto supermassive black holes (SMBHs) powers the most luminous persistent sources in the Universe, the so-called active galactic nuclei, whose emission is characterized by two distinct spectral components: thermal optical/ultraviolet (UV) radiation from an optically thick accretion disk and a power-law X-ray tail from a corona located in the innermost regions of the accretion flow. Yet, how radiatively efficient accretion disks develop and couple to the hot corona remains poorly understood. Using 6 yr of simultaneous UV and X-ray monitoring of the nearby active galaxy ESO 511-G030, we witness a dramatic evolution of the broadband spectral energy distribution, driven by an increase of the UV flux from the disk by more than 1 order of magnitude over a timescale of less than 3 yr. The overall behavior is unlikely to track an uncovering event and is instead compatible with a progressive recovery of the optically thick component of the accretion flow. At accretion rates higher than approximately 1% of the Eddington limit, UV and X-ray data are tightly coupled and follow the well-defined, nonlinear correlation between disk and corona found in the more luminous quasars. Below this threshold, the relation apparently breaks down, as expected in case of evaporation of the inner accretion disk into a geometrically thick, optically thin hot flow. This is a strong hint of an accretion-state transition analogous to those observed in stellar-mass black holes and confirms the need for a paradigm change in the models of radiatively efficient accretion flows around SMBHs.

We present VLT/ERIS integral field unit (IFU) J -band observations of MCG-03-34-64, a nearby ( z = 0.0167) Seyfert galaxy hosting a candidate dual active galactic nucleus (AGN) system with a separation of ∼100 pc between the nuclei, which are detected in Fe-K α X-ray images and [O III ] λ 5007Å narrow-band images. The ERIS observations cover, among others, the He I λ 1.083μm, [Fe II ] λ 1.257μm, and Pa β emission lines, over a field of view of 3″ × 3″ (∼1 × 1 kpc ² ). We analysed the ionised gas kinematics and identified two regions with an enhanced velocity dispersion ( W 80 ∼ 1500 km s ⁻¹ ), which is suggestive of fast outflowing gas, spatially coincident with the position of the two candidate active nuclei. We extracted the spectra from the two regions and used them to derive the properties of the ionised outflows. The two spectra show a prominent blueshifted wing with velocities v _max ∼ −1700 km s ⁻¹ , which corresponds to the highest 2 − 5 percentiles of samples of local AGN with similar bolometric luminosities (∼10 ⁴⁴ erg s ⁻¹ ). For the ionised phase of the two outflows, we derive comparable masses of ∼(4 ± 1)×10 ⁵ M _⊙ and mass outflow rates of ∼20 ± 5 M _⊙ yr ⁻¹ . The two distinct outflows could be associated with the two nuclei or be generated by the interaction of the radio jet with the interstellar medium (ISM). The map of the [Fe II ]/Pa β line ratio shows the highest values in the more external regions (compatible with shock excitation), intermediate values in the vicinity of the nuclei (compatible with AGN excitation), and lower values between the two nuclei, close to the peak of the optical and near-infrared continuum. We interpret this as due to a contribution to the Pa β emission from a nuclear starburst or to enhanced AGN ionisation. We also analysed the peculiar (very broad, boxy) profile of the [Fe VII ] λ 6087Å optical coronal line from an archival VLT/X-shooter spectrum. The comparison with the [Ne V ] λ 3425Å and [Fe II ] λ 1.257μm profiles indicates that [Fe VII ] emission likely arises only from the outflow. The absence of the systemic component in [Fe VII ] – unlike in [Ne V ], which has similar ionisation potential and critical density – suggests suppression of [Fe VII ] due to iron depletion onto dust grains, while its detection in the outflow implies a lower dust content than in the host ISM. The additional information gained from the ERIS data are consistent with the scenario of a dual AGN, however, further observations are required to confirm its nature.

We report on a nine-month monitoring campaign of the blazar PG 1553+113, relying on three observations carried out in 2025 with the Imaging X-ray Polarimetry Explorer (IXPE) and supported by multiwavelength facilities. The source displayed pronounced variability across the electromagnetic spectrum, with X-ray flux changes by up to a factor of ∼5 and complex evolution of the optical polarization properties, including one of the largest (exceeding 150°) and fastest rotations in the electric vector position angle (EVPA) ever recorded. This swing of the EVPA was also accompanied by a temporary drop of the optical polarization degree to nearly zero. Significant X-ray polarization was observed during the third IXPE pointing, with a polarization degree Π _X = (18.4 ± 5.8)% and Ψ _X = 74° ± 9° in the 2–8 keV band, while only upper limits were obtained in the first two epochs. The optical data show that the second IXPE observation occurred shortly after a dramatic optical polarization event characterized by a rapid EVPA swing and strong depolarization. Two possible scenarios may explain the broadband polarimetric behavior: (i) the superposition of two emitting regions with nearly orthogonal magnetic field configurations and variable relative contributions, and (ii) the interaction of a single emitting region with a shock that temporarily reorders the magnetic field. In both cases, the data support a picture in which the X-ray and optical emissions arise from closely related but not strictly cospatial regions within a dynamically evolving, magnetically structured jet.

Context. The analysis of X-ray absorption features in active galactic nuclei (AGN) provides a wealth of information about the physical properties of the matter surrounding supermassive black holes (SMBHs). While standard correlations between the ionisation state, column density, and velocity typically distinguish between disc winds and warm absorbers, some sources exhibit properties that significantly deviate from these trends. Aims. We investigate a class of X-ray absorbers, which we define as ultra-thick warm absorbers (UTWAs), identified in a sample of 12 AGN. These absorbers are characterised by exceptionally high column densities and ionisation parameters (log( N _H /cm ⁻² ) ≳ 22.5 and 0.5 ≲ log( ξ /erg cm s ⁻¹ ) ≲ 2.5) that lie outside the typical ranges observed in standard warm absorbers. Methods. We performed detailed X-ray spectral analyses of both unpublished and archival XMM-Newton , NuSTAR , and Swift datasets to characterise the physical properties of UTWAs in four of these twelve sources. We studied their variability on timescales ranging from days to years and explored their connection with other spectral features. Results. All AGN hosting UTWAs in our sample exhibit extreme soft X-ray variability, in some cases up to an order of magnitude, primarily driven by changes in the absorbing gas. In a subset of these sources (four out of 12), the UTWAs are accompanied by signatures of ultra-fast outflows (UFOs) in the Fe K α energy range. Conclusions. UTWAs represent a rare but crucial phase of AGN feedback. We discuss their physical origin, their potential connection with UFOs, and provide insights into why these high-column density, unusually ionised absorbers appear so rarely in local AGN samples.

NGC 4051 is a nearby (16.7 Mpc), Narrow Line Seyfert 1 galaxy (NLS1), which has a low black hole mass of 10 ⁶ M _⊙ . It is also known for its rapid X-ray variability, on timescales of kiloseconds, and has a complex, multicomponent wind in both the soft X-ray and Fe K bands. Here we present the first high-resolution XRISM Resolve spectrum of NGC 4051, which was captured in a historically bright state for a 150 ks exposure. XRISM resolves two blueshifted Fe K shell absorption troughs in the mean spectrum, which can be ascribed to H-like iron and arises from two outflow components with outflow velocities of 0.025 c and 0.04 c . A time-dependent spectral analysis shows that the iron K absorption is variable on timescales of less than a day, increasing in velocity over the duration of the observation. The velocity changes may be explained either by the passage of two separate transiting absorbers, of different velocities, or by a single accelerating outflow of approximately constant column density. In the latter case, the wind acceleration is likely to be too large to be caused by radiation pressure, and instead, magnetic driving is favored to accelerate the wind up to 0.04 c . The outflow can originate from an accretion disk wind, whose kinetic power is sub-Eddington, in contrast to recent examples of winds from powerful, luminous quasars observed by XRISM.

We present new Chandra/ACIS-S imaging spectroscopy of two luminous type 2 quasars (QSO2s), FIRST J120041.4+314745 ( z = 0.116) and 2MASX J13003807+5454367 ( z = 0.088), and compare their X-ray emission with Hubble Space Telescope [O III ] λ 5007 morphologies and kinematics. Both systems show kiloparsec-scale soft X-ray emission. In FIRST J120041, the X-ray morphology is clumpy and closely follows the [O III ] structures, with surface-brightness peaks cospatial with the highest [O III ] velocities (600–750 km s ⁻¹ ) and broadest line widths (∼1700 km s ⁻¹ ). In 2MASX J130038, the X-ray emission is centrally concentrated and weakly correlated with rotational [O III ] kinematics. Spectral modeling indicates that photoionization dominates the soft X-rays in both quasars. The inferred hot-gas reservoirs are substantial, M _Xray ∼ 4.5 × 10 ⁸ M _⊙ (FIRST J120041) and M _Xray ∼ 1.8 × 10 ⁸ M _⊙ (2MASX J130038), exceeding the outflowing [O III ] masses by factors of ∼4 and ∼16. In 2MASX J130038, we identify a tentative blueshifted Fe XXVI Ly α line at E _rest = 7.14 ± 0.06 keV ( v ∼ 7600 km s ⁻¹ ), consistent with a hot wind confined to the inner few hundred parsecs. Combining these results with a broader sample of 12 QSO2s, we argue that luminous quasars evolve along a continuous feedback sequence regulated by progressive clearing of circumnuclear gas. As active galactic nucleus radiation and winds pierce the surrounding medium, systems transition from heavily enshrouded, compact configurations to phases where the X-ray and [O III ] components strongly couple and, eventually, to energetically dominant outflows. FIRST J120041 and 2MASX J130038 represent two points along this sequence, tracing the emergence and growth of hot winds as primary drivers of quasar-scale feedback.

We present the first spatially resolved at ∼20 pc scale application of active galactic nuclei (AGN)-specific metallicity diagnostics for the nearby Compton-thick Seyfert 2 galaxy Mrk 573 ( z = 0.017). We use Hubble Space Telescope narrowband imaging, MUSE integral-field spectroscopy, and apply AGN strong-line metallicity diagnostics based on [O III ], [S II ], H β , H α , and [N II ] emission lines. We construct maps of 12 + log ( O / H ) for two different metallicity calibrations and two different N/O–O/H scaling relations out to ∼1 kpc and down to ∼20 pc scales. Our analysis reveals metallicity enhancement in AGN-dominated regions, with oxygen abundances reaching up to a few times solar. The metallicity shows a patchy spatial distribution, varying on ∼100 pc scales, which appears to trace the high Seyfert/ low-ionization nuclear emission-line region index value regions and the Very Large Array 6 cm jet/radio lobe emission. These spatial correspondences and the lack of evidence for star formation in the bicone region suggest that the enrichment originates from metals transported from the nuclear AGN regions by winds, outflows, or jets.