Alvaro Labiano

Context. Studies of the interstellar medium (ISM) have frequently revealed signatures of the dust produced in the envelopes of asymptotic giant branch (AGB) stars, demonstrating a connection between the dust composition of the ISM and that of AGB stellar envelopes. Investigating this relationship in the extreme, radiation-dominated environment surrounding Sgr A*, the center of our own galaxy, reveals how such conditions might influence dust composition and the recycling of material in galactic centers. Aims. IRS 3, the brightest L band source in the Galactic center and most prominent AGB star within the inner parsec of the Milky Way, is embedded in a dusty envelope with an estimated radius of ∼10 000 AU. We aim to conduct a comprehensive spectral analysis to more tightly constrain the dust composition and line-emitting species within the envelope of IRS 3 in the immediate vicinity of Sgr A*. Methods. In 2025, we observed the inner parsec of the Milky Way with the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST) as part of the guaranteed time observations (GTO) program Mid-Infrared Characterisation of Nearby Iconic galaxy Centres (MICONIC). We used the MIRI Medium Resolution Spectrometer (MRS) to study the spectroscopic characteristics of the AGB star IRS 3, located about 0.17 parsecs in projection from Sgr A*. Results. After correcting for foreground dust extinction along the line of sight using a stellar-based mid-infrared extinction curve, we find a broad 9.7 μm silicate stretching feature accompanied by an O-Si-O bending mode absorption feature at 18.5 μm in the spectrum of IRS 3. We used the radiative transfer code Hyperion to model the observed spectrum of IRS 3 with a best-fit stellar luminosity of 60 000 L _⊙ . Based on our model, we find a multi-shell configuration that exhibits a significant temperature gradient between the inner and outer layers of the envelope. A combination of alumina and amorphous silicates accurately reproduces the observed spectrum. We infer a stellar mass of about 6 M _⊙ and a corresponding age of ≈72 Myr. For the first time, we find clear signs of water in the envelope of IRS 3. Conclusions. Based on our MIRI MRS observations and the modeled spectrum, we conclude that the dusty envelope of IRS 3 is consistent with a shell-like distribution with a temperature gradient of ≈1000 K. Analysis of the MIRI MRS spectrum reveals the presence of amorphous silicates, Al ₂ O ₃ , and H ₂ O. A ratio of 3.5 ± 0.1 between the optical depth of the silicate Si-O stretching feature at 9.7 μm and the O-Si-O bending mode classifies IRS 3 as an O-rich star. Furthermore, assuming a wind velocity of v _w = 15 km/s, we estimate a mass-loss rate of 6 × 10 ⁻⁵ M _⊙ yr ⁻¹ and identify H ₂ O in the envelope of IRS 3. This finding demonstrates that the harsh radiation-dominated environment of Sgr A* does not inhibit dust formation or the survival of molecular species such as H ₂ O.

We present JWST MIRI medium-resolution spectrometer (MRS), NIRSpec, NIRCam, and MIRI imaging observations of 3C 305, a radio galaxy with a compact jet that is confined within the galaxy. We utilize the H ₂ 0–0 S(1)–S(7) lines, several mid-infrared (MIR) fine structure lines, and polycyclic aromatic hydrocarbon (PAH) emission in the MIRI MRS spectrum to conduct a multiphase study of the radio jet’s impact on the interstellar medium. Multiple tracers, including H ₂ /PAH 11.3 μ m and [Fe II ] 5.34 μ m, provide evidence for shocks at the jet termination locations. Two Gaussian components are required to reproduce the kinematics of warm H ₂ adequately, with one representing the bulk low-velocity component, while the other corresponds to an outflow. The ionized gas attains higher outflow velocities than the H ₂ outflow. The stark increase in velocities at the jet hotspots points to jet-driven outflows. We fit the H ₂ excitation diagram with a power-law temperature distribution and find that the hotspots exhibit flatter slopes, indicating a larger warm/hot gas mass fraction at these locations. Our MAPPINGS line-ratio analysis indicates that most of the MIR ionized gas can be fit by a “shock+precursor” model. We find that strong radiative losses dominated by line cooling, along with moderate kinetic power of the molecular + ionized gas outflows, can account for all of the estimated jet power, indicating high jet coupling efficiency in 3C 305. Our results, in tandem with other studies on multiphase gas, show that jets efficiently shock-heat and accelerate the gas that comes in contact with them, driving massive, kiloparsec-scale, multiphase outflows.

Jet–cloud interactions are a key manifestation of active galactic nucleus (AGN) feedback on nuclear scales, which is distinct from the large-scale radio-mode feedback that suppresses gas cooling in galaxy halos. On these smaller scales, radio jets can inject energy and momentum into the interstellar medium (ISM), shaping the physical and kinematic properties of the nuclear and circumnuclear regions of galaxies. Using JWST MIRI/MRS observations of seven nearby radio-loud AGNs (3C 293, 3C 305, Centaurus A, Cygnus A, IC 5063, NGC 1052, and M 87), we investigated jet-driven turbulence in both the warm molecular and ionized gas phases. By combining spatially resolved H ₂ /polycyclic aromatic hydrocarbon flux ratios with diagnostic line ratios of the ionized gas, we constrained the dominant H ₂ excitation processes and assessed the impact of radio jet–ISM interactions on the multiphase gas. We find that radio jets drive increased turbulence in both molecular and ionized (traced by [Fe II ], [Ne II ], and [Ne III ] lines) gas, not only along but also perpendicular to the jet axis, indicating that jet–ISM interactions extend beyond the collimated jet channel and affect the nuclear environment. Strong correlations between the H ₂ /polycyclic aromatic hydrocarbon ratio, the H ₂ excitation temperature, and shock-sensitive ionized-gas tracers indicate that jet-driven shocks dominate the excitation of the H ₂ rotational lines in most sources. These results indicate that radio jets are a key driver of multiphase ISM kinematics and excitation in nearby radio-loud galaxies.

Context. Supermassive black holes power active galactic nuclei (AGNs), injecting energy that may regulate accretion and shapes host galaxies. High-resolution observations of circumnuclear gas and dust are essential to understanding these processes. Aims. We aim to investigate the morphology, excitation, and kinematics of warm molecular hydrogen (H_2) in the inner circumnuclear disk of Centaurus A, the nearest radio galaxy. Methods. We present JWST/MIRI MRS integral-field spectroscopy of the central 170 Warm H_2 shows a complex morphology, dominating the central region where CO emission is weak or undetected. Low-excitation ̋mol lines trace an inhomogeneous ring with a 20-pc radius cavity aligned with the jet's near side, suggesting that the jet affects the morphology of the molecular disk. Higher excitation lines form a filamentary structure around the AGN. Kinematics are primarily rotational with an S-shaped distortion, indicating noncircular motions or a warped disk. A coherent, low-dispersion (∼70 100 pc2$ at 0.3"--0.7" (5--12 pc) resolution, focusing on pure rotational H_2 lines. The spectra exhibit a strong nuclear continuum, and bright H$_2 lines from S(1) to S(8), including the first S(8) detection in Centaurus A. The lines are optically thin in the nucleus, enabling maps of temperature, column density, and ortho-to-para ratio from spaxel-level excitation diagram fitting. Results. -1 $) streamer spirals inward. A power-law temperature distribution yields a warm (100--2000 K) H_2 mass of $(5.6 ± 1.4) , and sub-equilibrium ortho-to-para ratios (1.6--2.4). M_⊙ and a dynamical mass of 5 / M_⊙ within 100 pc. Shock excitation is supported by enhanced H_2/continuum and H$_2/PAH ratios, elevated Ne iii Ne ii Conclusions. Turbulent dissipation can balance the observed H_2 cooling and likely dominates heating beyond 30 pc. In the inner 100 pc of Centaurus A, AGN feeding and feedback are linked: shocks excite H_2, regulate the gas temperature, and prevent cooling below 100 K, explaining the weak CO emission and lack of a massive outflow. These shocks may drive angular-momentum loss and help fuel the nucleus.

Merging luminous galaxies are ideal laboratories for studying some of the most extreme astrophysical phenomena. The local ( z = 0.1232) obscured quasar J1356+1026 has two nuclei, North and South (J1356N and J1356S), but despite numerous efforts, J1356S had not yet been confirmed as an AGN. Based on the superb sensitivity and spatial resolution of the MIRI/MRS instrument on board the JWST, we present new evidence suggesting that J1356S may indeed host an AGN with log L _bol = 43.4±0.08 _0.5 ^0.6 erg s ⁻¹ . This is supported by the detection of strong coronal line emission at this location and by a spectral shape that differs from that of J1356N and those of the narrow-line region. Aided by the spatially resolved information of MIRI/MRS and VLT/SINFONI, we also found that the high-ionization gas, traced by the coronal lines [Ne V ]14.3 μm and [Si VI ]1.963 μm, extends from ∼13 − 15.5 kpc. This is likely a lower limit of the true extension, as suggested by the comparison with optical imaging from HST. The extended [Ne V ] emission can be accounted for by photoionization from the quasar in J1356N in a relatively low-density environment, ranging from n _e ≤ 2000 − 3800 cm ⁻³ in J1356N and n _e ≤ 600 − 1200 cm ⁻³ in J1356S and the narrow-line region, as measured from the [Ne V ]14.3 μm and 24.3 μm lines.

We utilize James Webb Space Telescope/Mid Infrared Instrument (JWST/MIRI) Integral Field Unit observations from the Galaxy Activity, Torus and Outflow Survey to investigate the diverse range of ionized outflow rates of obscured active galactic nuclei (AGN) with similar bolometric luminosity and explore potential associations with AGN feedback. We explore spatial correlations between ionized emission potentially associated with fast shocks ([Fe II ] _{5.34 μ m} ) and the excitation of H ₂ . We further constrain our investigation to the inner 400 pc (the nuclear and circumnuclear regions r < 200 pc), and estimate the excitation temperature and column density of H ₂ assuming local thermodynamic equilibrium and using the S(1)–S(8) rotational H ₂ emission lines visible to JWST/MIRI spectroscopy. We report the molecular gas temperature of the deprojected 400 pc nuclear region to correlate with the ionized mass outflow rate. We also observe a stronger degree of spatial correlation between [Fe II ] _{5.34 μ m} emission and H ₂ gas temperature. We observe regions of enhanced [Fe II ] _{5.34 μ m} /[Ar II ] _{6.99 μ m} spatially coincident with the ionization cones of objects with higher ionized outflow rates and [Fe II ] _{5.34 μ m} /[Ar II ] _{6.99 μ m} in the deprojected 400 pc nuclear region to scale positively with both the ionized outflow rate and the estimated molecular gas temperature. We do not observe the estimated jet cavity power within the central 400 pc as strongly correlated with the ionized mass outflow rate or molecular gas temperature of the nuclear region. We take the preceding observations to suggest a higher degree of interaction between AGN outflows and the circumnuclear disk.

Context. The European Archive of the James Webb Space Telescope (eJWST) provides access to all data collected by the James Webb Space Telescope (JWST). JWST's capabilities span from studying early universe galaxy formation to probing exoplanet atmospheres. Specifically, for Active Galactic Nuclei (AGN), JWST offers unparalleled opportunities, enabling investigation into AGN phenomena with unprecedented detail through high-resolution imaging, spectroscopy, and photometric data. Aims. This study aims to compile and release a catalogue of all AGN observations conducted with JWST. Using eJWST, we systematically filter and organize these observations to facilitate access and retrieval of all of JWST's data products related to AGNs. Our goal is to provide the community with a valuable resource for their research. Methods. We compiled the AGN observations in eJWST using specific keywords set by the principal investigators in their proposals, manually reviewing the approved programs of JWST, as well as cross-matching all available observations with available AGN catalogues such as the Million Quasar catalogue, the SDSS MaNGA AGN catalogue, the CDFS catalogue, and others. Results. The resulting catalogue contains a total of 3,242 individual AGNs included in JWST observations. This is one of the first extensive collections of AGN observations from the JWST. It includes detailed information about the targets (name, coordinates, redshift), specifics of the JWST observations (instrument, aperture, filter, etc.), and provides links for data downloads.

The polar mid-infrared (MIR) emission detected within tens to hundreds of parsecs in some active galactic nuclei (AGN) has been associated with dusty winds driven away by radiation pressure. The physical characterization of this extended polar emission remains uncertain. Here, we combine 10–21 μ m JWST/Mid-InfRared Instrument (MIRI) imaging observations with 7–25 μ m JWST/MIRI MRS integral field spectroscopic observations of six nearby, D ¯ = 35.4 ± 4.6 Mpc, AGN from the GATOS Survey to quantify the nature of the extended MIR emission at ∼75 pc resolution at 21 μ m. These AGN have similar bolometric luminosities, log 10 ( L ¯ bol [ erg s − 1 ] ) = 44.0 ± 0.3 , span a wide range of optical outflow rates, M ̇ = 0.003–0.21 M _⊙ yr ⁻¹ , column densities, log 10 ( N H X − ray [ cm − 2 ] ) = 22.2–24.3, and Eddington ratios, λ _Edd = 0.005–0.06. We cross-correlate the line-only and continuum-only images and find a poor correlation, which indicates that the extended MIR continuum emission is spatially uncorrelated with the warm outflows associated with narrow emission lines within 10–15 μ m. Line emission is resolved along the jet axis, while dust emission is perpendicular to it. The 75–450 pc continuum emission has a fairly constant dust temperature, T d = 13 2 − 7 + 7 K, and mass, M d = 72 8 − 27 + 29 M _⊙ . Using the conditions of energy balance between radiation-pressure and gravity ( λ _Edd versus N _H ), we find that our AGN sample is in the gravitationally bounded regime consistent with no detection of dusty winds. At 10 μ m, the level of extended line emission contribution is correlated with the outflow kinetic energy and mass outflow rates. We find no correlation with the AGN properties. These results indicate that the radio jet may be triggering the gas outflow and line emission, while the extended dust emission is distributed in molecular clouds and/or shocked regions.

We present a comprehensive analysis of the MIRI Extremely Red Object Virgil, a Ly α emitter at z _spec = 6.6379 ± 0.0035 with the photometric properties of a Little Red Dot. Leveraging new JWST/MIRI imaging from the MIDIS and PAHSPECS programs, we confirm Virgil’s extraordinary nature among galaxies in JADES/GOODS-South, exhibiting a strikingly red NIRCam-to-MIRI color (F444W–F1500W = 2.84 ± 0.04 mag). Deep NIRSpec/PRISM spectroscopy from the OASIS program offers key insights into the host galaxy, revealing properties of an average star-forming galaxy during Cosmic Reionization, such as a subsolar metallicity, low-to-moderate dust content, and a relatively high ionization parameter and electron temperature. By estimating the star formation rate of Virgil from UV and H α , we find evidence that the galaxy is either entering or fading out of a bursty episode. Although line-ratio diagnostics employed at high z would classify Virgil as an active galactic nucleus (AGN), this classification becomes ambiguous once redshift evolution is considered. Nonetheless, Virgil occupies the same parameter space as recently confirmed AGNs at similar redshifts. The new deep MIRI data at 15 μ m reinforce the AGN nature of Virgil, as inferred from multiple spectral energy distribution (SED) fitting codes. Virgil’s rising infrared SED and UV excess resemble those of Dust-Obscured Galaxies (DOGs) studied with Spitzer at Cosmic Noon, particularly blue-excess HotDOGs. Our results highlight the need for a multiwavelength approach incorporating MIRI to uncover such extreme sources at z ≳ 6 and to shed light on the interplay between galaxy evolution and early black hole growth during Cosmic Reionization.

We utilize James Webb Space Telescope (JWST) Mid Infrared Instrument (MIRI) integral field unit observations to investigate the behavior and excitation of H ₂ in the nearby Seyfert galaxies NGC 3081 and NGC 5506, both part of the Galactic Activity, Torus, and Outflow Survey (or GATOS). We compare population levels of the S(1) to S(8) rotational H ₂ emission lines visible to JWST/MIRI spectroscopy to models assuming local thermodynamic equilibrium (LTE), in order to estimate the column density and thermal scaling of the molecular gas. For the nuclear regions, we incorporate Very Large Telescope Spectrograph for INtegral Field Observations in the Near Infrared (or VLT/SINFONI) K -band observations to estimate population levels for available rovibrational H ₂ emission lines, and compare the resultant population curves to non-LTE radiative transfer models and shock modeling. We report a differing set of prominent active galactic nuclei (AGN)-driven excitation mechanisms between the two galaxies. For NGC 3081, we find that a non-LTE radiative transfer environment is adequate to explain observations of the nuclear region, indicating that the primary mode in which the AGN transfers excitation energy is likely irradiation. We estimate the extent of AGN photoionization along the ionization bicone to be ≈330 pc. In contrast, for NGC 5506, we find a shock scenario to be a more plausible excitation mechanism, a conclusion bolstered by an observed spatial correlation between higher-energy rotational H ₂ and [Fe II ] _{5.34 μ m} emission. In addition, we identify potential nuclear H ₂ outflows resulting from an interaction between the ionization bicone and the rotational disk. By isolating the outflowing component of the H ₂ emission, we estimate the warm molecular mass outflow rate to be 0.07 M _⊙ yr ⁻¹ .