Begona Garcia Lorenzo

Context. QUIJOTE is a cosmic microwave background (CMB) experiment composed of two telescopes, QT1 and QT2, located at the Teide Observatory (OT) in Tenerife, Spain. The multifrequency instrument (MFI) (2012–2018), installed on QT1, observed the sky at four frequency bands, namely 11, 13, 17, and 19 GHz, with an angular resolution of one degree. Its successor, the Second Multifrequency Instrument (MFI2), began operations in early 2024 and operates in the same frequency bands. Aims. This paper has two main goals. First, we characterise the atmospheric conditions at the Teide Observatory. Second, we carry out an empirical characterisation of the atmospheric turbulence using observations from both QUIJOTE MFI and MFI2. This work has implications for both atmospheric physics and CMB observations, and can be used for future reanalyses of MFI data or in the preparation for upcoming instruments such as the Tenerife Microwave Spectrometer (TMS). Methods. We used data from GPS antennas, the STELLA observatory, and radio soundings to derive median profiles and distributions of key atmospheric parameters in the period 2012–2018. We then analysed MFI data to compute atmospheric structure functions at 17 and 19 GHz. Using the full MFI database, we studied the correlation properties of the atmospheric signal by calculating the cross-correlation function of the time-ordered data between horns operating at the same frequency. Finally, we used MFI2 observations to study the atmospheric power spectrum and compared it to the determination of the structure function based on MFI data. Results. The water vapour density profile above the observatory can be well described by an exponential decay law, with a characteristic half-height of about 1000 m. Median values of precipitable water vapour (PWV) in the 2012–2018 period are 3.3 mm, with a 25th percentile of 2.1 mm. For high PWV conditions, we find that the structure function estimated with MFI data is consistent with the Kolmogorov turbulence model. The slope of the power spectrum of the atmospheric emission also seems consistent with the prediction of this model, although within a range of frequencies limited by the outer scale and by the instrument noise. Furthermore, through the study of the coherence length in the correlation function, we confirmed that atmospheric conditions remain stable for a period of about 1–2 hours. These results show that the Teide Observatory has an atmospheric behaviour comparable to that of the Atacama Cosmology Telescope (ACT) site, although with higher integrated precipitable water vapour due to its lower altitude.

Context. With the rise of integral field spectroscopy (IFS), we are currently dealing with large amounts of spatially resolved data, whose analysis has become challenging, especially when observing complex objects such as nearby galaxies. Aims. We aim to develop a method of automatically separating regions with different physical properties (ionisation, kinematics, etc.) within the central parts (1″ ∼ 160 pc, on average) of galaxies. This could allow us to better understand the systems and provide an initial characterisation of the main ionisation sources affecting its evolution. Methods. We developed an unsupervised hierarchical clustering algorithm to analyse data cubes based on spectral similarity. It clusters spaxels together with similar spectra, which is useful to disentangle regions affected by different processes, such as ionisation sources. We applied this method to a sample of 15 nearby (distances < 100 Mpc) galaxies: 7 from the Galaxy Activity, Torus, and Outflow Survey (GATOS) and 8 archival sources, all observed with the medium-resolution spectrometer (MRS) of the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST). The sample spans sources of various morphologies, active galactic nucleus (AGN) types, and/or starbursts. From the clusters, we computed their median spectrum and measured the line and continuum properties. We used these measurements to train random forest models and create several empirical mid-IR diagnostic diagrams for the MRS channel 3 wavelength range, ranging from 11.5 to 18 μm, which includes among others the bright [Ne II], [Ne III], and [Ne V] lines, several H ₂ transitions, and PAH features. Results. The clustering technique allows one to differentiate emission coming from an AGN, a nuclear starburst, the disc and star-forming (SF) regions in the galaxies, and other composite regions, potentially ionised by several sources simultaneously. This is supported by the results from the empirical diagnostic diagrams, which are indeed able to separate physically distinct regions. This innovative method serves as a tool to identify regions of interest in any data cube prior to an in-depth analysis of the sources. In a future work, we shall explore other wavelength ranges and a larger sample that would help us to obtain statistically significant conclusions.

Active galactic nuclei (AGNs), star formation (SF), and galaxy interactions can drive turbulence in the gas of the interstellar medium (ISM), which, in turn, plays a role in SF taking place within galaxies. The impact on molecular gas is of particular importance, as it serves as the primary fuel for SF. Our goal is to investigate the origin of turbulence and the emission of molecular gas, as well as low-and-intermediate-ionisation gas, in the inner few kpc of both AGN hosts and star-forming galaxies (SFGs). We used archival JWST MIRI/MRS observations of a sample consisting of 54 galaxies at z < 0.1. We present flux measurements for the H ₂ S(5) λ 6.9091 μm, [Ar II ] λ 6.9853 μm, [Fe II ] λ 5.3403 μm, and [Ar III ] λ 8.9914 μm emission lines along with velocity dispersion estimated by the W ₈₀ parameter. For galaxies with coronal line emission, we included measurements of the [Mg V ] λ 5.6098 μm line. We compared the line ratios to photoionisation and shock models to explore the origin of the gas emission. AGNs exhibit broader emission lines than SFGs, with the largest velocity dispersions observed in radio-strong (RS) AGNs. The H ₂ gas is less turbulent compared to ionised gas, while coronal gas presents higher velocity dispersions. The W ₈₀ values for the ionised gas show a decrease when going from the nucleus out to radii of approximately 0.5–1 kpc, followed by an outward increase up to 2–3 kpc. In contrast, the H ₂ line widths generally display increasing profiles with distance from the center. Correlations between the W ₈₀ parameter and line ratios such as H ₂ S(5)/[Ar II ] and [Fe II ]/[Ar II ] indicate that the most turbulent gas is associated with shocks, enhancing H ₂ and [Fe II ] emissions. Based on the observed line ratios and velocity dispersions, the [Fe II ] emission is consistent with predictions of fast shock models, while the H ₂ emission is likely associated with molecules formed in the post-shock region. We speculate that these shocked gas regions are produced by AGN outflows and jet-cloud interactions in AGN-dominated sources; whereas in SFGs, they might be created through stellar winds and mergers. This shock-induced gas heating may be an important mechanism of AGN (or stellar) feedback, preventing the gas from cooling and forming new stars.

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 observations of the type-2 Seyfert NGC 7172 obtained with the medium-resolution spectrometer (MRS) of the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST). This galaxy hosts one of the lowest ionised gas mass outflow rates (Ṁ_out ∼ 0.005 M_⊙ yr⁻¹) in a sample of six active galactic nuclei (AGN) with similar bolometric luminosities (log L_bol ∼ 44 erg s⁻¹) within the Galactic Activity, Torus, and Outflow Survey (GATOS). We aim to understand the properties of the ionised gas outflow and its impact on the host galaxy. We mainly used the ionised gas emission lines from the neon transitions, which cover a broad range of ionisation potentials (IPs) from ∼20 eV to ∼130 eV. We applied parametric and non-parametric methods to characterise the line emission and kinematics. The low excitation lines (IP < 25 eV, e.g. [Ne II]) trace the rotating disc emission. The high excitation lines (IP > 90 eV, e.g. [Ne V]), which are likely photoionised exclusively by the AGN, are expanding in the direction nearly perpendicular to the disc of the galaxy, with maximum projected velocities in the range of ∼350–500 km s⁻¹. In particular, [Ne V] and [Ne VI] lines reveal a biconical ionised gas outflow emerging north-south from the nuclear region, extending at least ∼2.5″ N and 3.8″ S (projected distance of ∼450 and 680 pc, respectively). Most of the emission arising in the northern part of the cone was not previously detected due to obscuration. Given the almost face-on orientation of the outflow and the almost edge-on orientation of the galaxy, NGC 7172 may be a case of weak coupling. Nevertheless, we found evidence of positive feedback in two distinct outflowing clumps at projected distances of 3.1″ and 4.3″ (i.e. ∼560 and 780 pc) south-west of the AGN. We estimated a star formation rate in these regions using the [Ne II] and [Ne III] luminosities of 0.08 M_⊙ yr⁻¹, which is ∼10% of that found in the circumnuclear ring. The star formation activity might have been triggered by the interaction between the ionised gas outflow and the interstellar medium of the galaxy.

The ionisation cones of NGC 5728 have a deficit of molecular gas based on millimetre observations of CO (2-1) emission. Although photoionisation from the active nucleus may lead to suppression of this transition, warm molecular gas can still be present. We report the detection of eight mid-infrared rotational H₂ lines throughout the central kiloparsec, including the ionisation cones, using integral field spectroscopic observations with JWST/MIRI MRS. The H₂ line ratios, characteristic of a power-law temperature distribution, indicate that the gas is warmest where it enters the ionisation cone through disk rotation, suggestive of shock excitation. In the nucleus, where the data can be combined with an additional seven ro-vibrational H₂ transitions, we find that moderate velocity (30 km s⁻¹) shocks in dense (10⁵ cm⁻³) gas, irradiated by an external UV field (G₀ = 10³), do provide a good match to the full set. The warm molecular gas in the ionisation cone that is traced by the H₂ rotational lines has been heated to temperatures > 200 K. Outside of the ionisation cone the molecular gas kinematics are undisturbed. However, within the ionisation cone, the kinematics are substantially perturbed, indicative of a radial flow, but one that is quantitatively different from the ionised lines. We argue that this outflow is in the plane of the disk, implying a short 50 pc acceleration zone up to speeds of about 400 km s⁻¹ followed by an extended deceleration over ∼700 pc where it terminates. The deceleration is due to both the radially increasing galaxy mass, and mass-loading as ambient gas in the disk is swept up.

Context. The spatial coherence wavefront outer scale (ℒ₀) characterizes the size of the largest turbulence eddies in Earth’s atmosphere, determining low spatial frequency perturbations in the wavefront of the light captured by ground-based telescopes. Advances in adaptive optics (AO) techniques designed to compensate for atmospheric turbulence emphasize the crucial role of this parameter for the next generation of large telescopes. Aims. The motivation of this work is to introduce a novel technique for estimating ℒ₀ from seeing-limited integral field spectroscopic (IFS) data. This approach is based on the impact of a finite ℒ₀ on the light collected by the pupil entrance of a ground-based telescope. Methods. We take advantage of the homogeneity of IFS observations to generate band filter images spanning a wide wavelength range, enabling the assessment of image quality (IQ) at the telescope’s focal plane. Comparing the measured wavelength-dependent IQ variation with predictions derived from a first-order analytical approach based on turbulence statistics simplifications using the von Kármán model provides valuable insights into the prevailing ℒ₀ parameter during the observations. We applied the proposed technique to observations from the Multi-Unit Spectroscopic Explorer (MUSE) in the wide-field mode obtained at the Paranal Observatory. Results. Our analysis successfully validates the first-order analytical expression, which combines the seeing (ε₀) and the ℒ₀ parameters, to predict the IQ variations with the wavelength in ground-based astronomical data. However, we observed some discrepancies between the measured and predictions of the IQ that are analyzed in terms of uncertainties in the estimated ε₀ and dome-induced turbulence contributions. Conclusions. This work constitutes the empirical validation of the analytical expression for estimating IQ at the focal plane of ground-based telescopes under specific ε₀ and finite ℒ₀ conditions. Additionally, we provide a simple methodology to characterize the ℒ₀ and dome-seeing (ε_dome) as by-products of IFS observations routinely conducted at major ground-based astronomical observatories.

We present new optical GTC/MEGARA seeing-limited (0.9″) integral-field observations of NGC 5506, together with ALMA observations of the CO(3 − 2) transition at a 0.2″ (∼25 pc) resolution. NGC 5506 is a luminous (bolometric luminosity of ∼10⁴⁴erg s⁻¹) nearby (26 Mpc) Seyfert galaxy, part of the Galaxy Activity, Torus, and Outflow Survey (GATOS). We modelled the CO(3 − 2) kinematics with^3DBAROLO, revealing a rotating and outflowing cold gas ring within the central 1.2 kpc. We derived an integrated cold molecular gas mass outflow rate for the ring of ∼8 M_⊙yr⁻¹. We fitted the optical emission lines with a maximum of two Gaussian components to separate rotation from non-circular motions. We detected high [OIII]λ5007 projected velocities (up to ∼1000 km s⁻¹) at the active galactic nucleus (AGN) position, decreasing with radius to an average ∼330 km s⁻¹around ∼350 pc. We also modelled the [OIII] gas kinematics with a non-parametric method, estimating the ionisation parameter and electron density in every spaxel, from which we derived an ionised mass outflow rate of 0.076 M_⊙yr⁻¹within the central 1.2 kpc. Regions of high CO(3 − 2) velocity dispersion, extending to projected distances of ∼350 pc from the AGN, appear to be the result from the interaction of the AGN wind with molecular gas in the galaxy’s disc. Additionally, we find the ionised outflow to spatially correlate with radio and soft X-ray emission in the central kiloparsec. We conclude that the effects of AGN feedback in NGC 5506 manifest as a large-scale ionised wind interacting with the molecular disc, resulting in outflows extending to radial distances of 610 pc.

The superb image quality, stability, and sensitivity of JWST permit deconvolution techniques to be pursued with a fidelity unavailable to ground-based observations. We present an assessment of several deconvolution approaches to improve image quality and mitigate the effects of the complex JWST point-spread function (PSF). The optimal deconvolution method is determined by using WebbPSF to simulate JWST’s complex PSF and MIRISim to simulate multiband JWST/Mid-Infrared Imager Module (MIRIM) observations of a toy model of an active galactic nucleus (AGN). Five different deconvolution algorithms are tested: (1) Kraken deconvolution, (2) Richardson–Lucy, (3) the adaptive imaging deconvolution algorithm, (4) sparse regularization with the Condat–Vũ algorithm, and (5) iterative Wiener filtering and thresholding. We find that Kraken affords the greatest FWHM reduction of the nuclear source of our MIRISim observations for the toy AGN model while retaining good photometric integrity across all simulated wave bands. Applying Kraken to Galactic Activity, Torus, and Outflow Survey (GATOS) multiband JWST/MIRIM observations of the Seyfert 2 galaxy NGC 5728, we find that the algorithm reduces the FWHM of the nuclear source by a factor of 1.6–2.2 across all five filters. Kraken images facilitate detection of extended nuclear emission ∼2.″5 (∼470 pc, position angle ≃ 115°) in the SE–NW direction, especially at the longest wavelengths. We demonstrate that Kraken is a powerful tool to enhance faint features otherwise hidden in the complex JWST PSF.

Nearby metal-poor starburst dwarf galaxies present a unique opportunity to probe the physics of high-density star formation with a detail and sensitivity unmatched by any observation of the high-z Universe. Here we present the first results from a chemodynamical study of the nearby, gas-rich starburst dwarf CGCG 007-025. We use VLT/MUSE integral field spectroscopy to characterise the properties of the star-forming (SF) gas, from its metal content to its kinematics. The star formation rate (SFR) surface density presents a clumpy distribution, with the brightest knot hosting a 5 Myr young, Wolf-Rayet (WR) population (revealed by the presence of the characteristic 5808ÅWR bump). The ionised gas kinematics are dominated by disordered motions. A superposition of a narrow (σ ≈ 50 km s⁻¹), intermediate (150 km s⁻¹) and broad (1000 km s⁻¹) kinematic components are needed to model the emission line profiles in the brightest SF region, suggesting the presence of energetic outflows from massive stars. The gas-phase metallicity of the galaxy spans 0.6 dex and displays a strong anti-correlation with SFR surface density, dropping to 12+log(O/H) = 7.7 in the central SF knot. The spatially-resolved BPTs indicates the gas is being ionised purely by SF processes. Finally, the anti-correlation between the SFR and the gas metallicity points out to accretion of metal-poor gas as the origin of the recent off-centre starburst, in which the infalling material ignites the SF episode.