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The next generation Event Horizon Telescope (ngEHT) will observe multiple supermassive black hole (SMBH) candidates down to a few tens of mJy, and profoundly transform our understanding of the local SMBH population. Given the impossibility of large-area high-resolution millimeter surveys, multi-frequency spectral energy densities (SEDs), and models are required to both identify source samples tailored to specific science goals, and to predict the feasibility of detection of individual interesting sources. Here, we present the Event Horizon and Environs (ETHER) source and SED model database whose primary use is to enable the selection and optimization of targets for EHT and ngEHT science. The living ETHER database currently consolidates 1.6 million black hole mass estimates, ∼15,500 milliarcsec-scale radio fluxes, ∼14,000 hard X-ray fluxes (expected to grow by factor ≳40 with the eROSITA data release) and SED information as obtained from catalogs and database queries, the literature, and our own new observations. Jet and accretion flow models are fit to individual SEDs in an automated way in order to predict the ngEHT observable fluxes from the jet base and accretion inflow. The database can be filtered by parameters or cross matched to a user source list, with the automated SED fitting models optionally fine tuned by the user. We have identified an initial ngEHT ‘gold sample’ for jet base studies and potentially black hole shadows; this sample will grow significantly in the coming years. While the ngEHT requires and will best exploit the ETHER database, six (eleven) ETHER sources have already been observed (scheduled) with the EHT in 2022 (2023), and the database has wide ranging applications in galaxy and black hole mass evolution studies.

Mrk 590 is a known changing-look AGN which almost turned off in 2012, and then in 2017 partially re-ignited into a repeat flaring state, unusual for an AGN. Our \emph{Swift} observations since 2013 allow us to characterise the accretion-generated emission and its reprocessing in the central engine of a changing-look AGN. The X-ray and UV variability amplitudes are higher than those typically observed in `steady-state' AGN at similar moderate accretion rates; instead, the variability is similar to that of highly accreting AGN. The unusually strong X-ray to UV correlation suggests that the UV-emitting region is directly illuminated by X-ray outbursts. We find evidence that the X-rays are reprocessed by two UV components, with the dominant one at $\sim$3 days and a faint additional reprocessor at near-zero lag. However, we exclude a significant contribution from diffuse broad line region continuum, known to contribute for bona-fide AGN. A near-zero lag is expected for a standard `lamp-post' disk reprocessing model with a driving continuum source near the black hole. That the overall UV response is dominated by the $\sim$3-day lagged component suggests a complicated reprocessing geometry, with most of the UV continuum not produced in a compact disk, as also found in recent studies of NGC 5548 and NGC 4151. Nonetheless, the observed flares display characteristic timescales of $\sim$100 rest-frame days, consistent with the expected thermal timescale in an accretion disk., Comment: 25 pages; published in MNRAS, Dec 2nd 2022. Updated to correct incorrect citation in bibliography, Jan 2nd 2023

We analyze a sample of 25 [Ne v] (λ3426) emission-line galaxies at 1.4 < z < 2.3 using Hubble Space Telescope/Wide Field Camera 3 G102 and G141 grism observations from the CANDELS Lyα Emission at Reionization (CLEAR) survey. [Ne v] emission probes extremely energetic photoionization (creation potential of 97.11 eV) and is often attributed to energetic radiation from active galactic nuclei (AGNs), shocks from supernovae, or an otherwise very hard ionizing spectrum from the stellar continuum. In this work, we use [Ne v] in conjunction with other rest-frame UV/optical emission lines ([O ii] λ λ3726, 3729, [Ne iii] λ3869, Hβ, [O iii] λ λ4959, 5007, Hα+[N ii] λ λ6548, 6583, [S ii] λ λ6716, 6731), deep (2–7 Ms) X-ray observations (from Chandra), and mid-infrared imaging (from Spitzer) to study the origin of this emission and to place constraints on the nature of the ionizing engine. The majority of the [Ne v]-detected galaxies have properties consistent with ionization from AGNs. However, for our [Ne v]-selected sample, the X-ray luminosities are consistent with local (z ≲ 0.1) X-ray-selected Seyferts, but the [Ne v] luminosities are more consistent with those from z ∼ 1 X-ray-selected QSOs. The excess [Ne v] emission requires either reduced hard X-rays or a ∼0.1 keV excess. We discuss possible origins of the apparent [Ne v] excess, which could be related to the “soft (X-ray) excess” observed in some QSOs and Seyferts and/or be a consequence of a complex/anisotropic geometry for the narrow-line region, combined with absorption from a warm, relativistic wind ejected from the accretion disk. We also consider implications for future studies of extreme high-ionization systems in the epoch of reionization (z ≳ 6) with the James Webb Space Telescope.

We present visual classifications of merger-induced tidal disturbances in 143 M-* similar to 10(11)M(circle dot) post-starburst galaxies at z similar to 0.7 identified in the. SQuIGG (L) over right arrowE Sample. This sample spectroscopically selects galaxies from the Sloan Digital Sky Survey that have stopped their primary epoch of star formation within the past similar to 500 Myr. Visual classifications are performed on Hyper Suprime-Cam imaging. We compare to a control sample of mass- and redshift-matched star-forming and quiescent galaxies from the Large Early Galaxy Census and find that post-starburst galaxies are more likely to be classified as disturbed than either category. This corresponds to a factor of 3.6(-1.3)(+2.9) times the disturbance rate of older quiescent galaxies and 2.1(-.73)(+1.9) times the disturbance rate of star-forming galaxies. Assuming tidal features persist for less than or similar to 500 Myr, this suggests merging is coincident with quenching in a significant fraction of these post-starbursts. Galaxies with tidal disturbances are younger on average than undisturbed post-starburst galaxies in our sample, suggesting tidal features from a major merger may have faded over time. This may be exacerbated by the fact that, on average, the undisturbed subset is fainter, rendering low- surface-brightness tidal features harder to identify. However, the presence of 10 young (less than or similar to 150 Myr since quenching) undisturbed galaxies suggests that major mergers are not the only fast physical mechanism that shut down the primary epoch of star formation in massive galaxies at intermediate redshift.

The mid-infrared spectra of star-forming galaxies (SFGs) are characterized by characteristic broad PAH emission features at 3$-$20 $\mu$m. As these features are redshifted, they are predicted to dominate the flux at specific mid-infrared wavelengths, leading to substantial redshift-dependent color variations in broad-band photometry. The advent of JWST for the first time allows the study of this effect for normal SFGs. Based on spectral energy distribution templates, we here present tracks in mid-infrared (4.4, 7.7, 10, 15, and 18 $\mu$m) color-color diagrams describing the redshift dependence of SFG colors. In addition, we present simulated color-color diagrams by populating these tracks using the cosmic star-formation history and the star-formation rate function. Depending on redshift, we find that SFGs stand out in the color-color diagrams by several magnitudes. We provide the first observational demonstration of this effect for galaxies detected in the JWST Early Release Observations of the field towards the lensing cluster SMACS J0723.3$-$7327. While the distribution of detected galaxies is consistent with the simulations, the numbers are substantially boosted by lensing effects. The PAH emitter with the highest spectroscopic redshift, detected in all bands, is a multiply-imaged galaxy at $z=1.45$. There is also a substantial number of cluster members, which do not exhibit PAH emission, except for one Seyfert galaxy at $z=0.38$. Future wider-field observations will further populate mid-infrared color-color diagrams and provide insight into the evolution of typical SFGs., Comment: 8 pages, 5 figures, Submitted to ApJL, Comments are Welcome!

The optical and UV properties of radio-quiet (RQ) and radio-loud (RL, relativistically “jetted”) active galactic nuclei (AGN) are known to differ markedly; however, it is still unclear what is due to a sample selection and what is associated with intrinsic differences in the inner workings of their emitting regions. Chemical composition is an important parameter related to the trends of the quasar main sequence. Recent works suggest that in addition to physical properties such as density, column density, and ionization level, strong Feii emitters require very high metal content. Little is known, however, about the chemical composition of jetted radio-loud sources. In this short note, we present a pilot analysis of the chemical composition of low-z radio-loud and radio-quiet quasars. Optical and UV spectra from ground and space were combined to allow for precise measurements of metallicity-sensitive diagnostic ratios. The comparison between radio-quiet and radio-loud was carried out for sources in the same domain of the Eigenvector 1/main sequence parameter space. Arrays of dedicated photo-ionization simulations with the input of appropriate spectral energy distributions indicate that metallicity is sub-solar for RL AGN, and slightly sub-solar or around solar for RQ AGN. The metal content of the broad line-emitting region likely reflects a similar enrichment story for both classes of AGN not involving recent circum-nuclear or nuclear starbursts.

We thank the anonymous referee for providing useful comments that improved the quality of the paper. We thank Ian Smail for very helpful discussions. This publication uses data from the ALMA programs: ADS/JAO.ALMA# 2018.1.00035.L, #2013.1.00999.S, and #2015.1.01425.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. This work has been financially supported by JSPS KAKENHI grant Nos. 22J22795 (R.U.), 20H01946 (Y.U.), 17H06130 (K.K., Y.U.), 19K14759 (Y.T.), and 22H01266 (Y. T.), and the NAOJ ALMA Scientific Research grant No. 2017- 06B (K.K.). S.Y. is grateful for support from RIKEN Special Postdoctoral Researcher Program. F.S. acknowledges support from the NRAO Student Observing Support (SOS) award SOSPA7-022. G.E.M. acknowledges the Villum Fonden research grants 13160 and 37440 and the Cosmic Dawn Center of Excellence funded by the Danish National Research Foundation under grant No. 140. H.U. acknowledges support from JSPS KAKENHI under grant No. 20H01953. D.E. acknowledges support from a Beatriz Galindo senior fellowship (BG20/00224) from the Spanish Ministry of Science and Innovation, projects PID2020-114414GB-100 and PID2020-113689GB-I00 financed by MCIN/AEI/ 10.13039/501100011033, project P20_00334 financed by the Junta de Andalucía, and project A-FQM-510-UGR20 of the FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades, We report the multiwavelength properties of millimeter galaxies hosting X-ray detected active galactic nuclei (AGNs) from the ALMA Lensing Cluster Survey (ALCS). ALCS is an extensive survey of well-studied lensing clusters with ALMA, covering an area of 133 arcmin(2) over 33 clusters with a 1.2 mm flux-density limit of similar to 60 mu Jy (1 sigma). Utilizing the archival data of Chandra, we identify three AGNs at z = 1.06, 2.09, and 2.84 among the 180 millimeter sources securely detected in the ALCS (of which 155 are inside the coverage of Chandra). The X-ray spectral analysis shows that two AGNs are not significantly absorbed (log N-H cm (2) < 23 -), while the other shows signs of moderate absorption (log NH cm (2) similar to 23.5 -). We also perform spectral energy distribution modeling of X-ray to millimeter photometry. We find that our X-ray AGN sample shows both high mass-accretion rates (intrinsic 0.5-8 keV X-ray luminosities of similar to 10(44-45) erg s(-1)) and star formation rates (> 100 Me yr-1). This demonstrates that a wide-area survey with ALMA and Chandra can selectively detect intense growth of both galaxies and supermassive black holes in the high-redshift universe., Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research (KAKENHI) A-FQM-510-UGR20, NAOJ ALMA Scientific Research 22J22795, RIKEN Special Postdoctoral Researcher Program, NRAO Student Observing Support (SOS) 20H01946, Villum Fonden 17H06130 19K14759, Cosmic Dawn Center of Excellence - Danish National Research Foundation 22H01266, Ministry of Science and Innovation, Spain (MICINN) Spanish Government, Junta de Andalucia, FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades, MCIN/AEI 2017-06B, SOSPA7-022, 13160, 37440, 140, 20H01953, BG20/00224, PID2020-114414GB-100, PID2020-113689GB-I00, P20_00334

We report the multi-wavelength properties of millimeter galaxies hosting X-ray detected active galactic nuclei (AGNs) from the ALMA Lensing Cluster Survey (ALCS). ALCS is an extensive survey of well-studied lensing clusters with ALMA, covering an area of 133 arcmin$^2$ over 33 clusters with a 1.2 mm flux-density limit of ${\sim}$60 $\mathrm{\mu Jy}$ ($1\sigma$). Utilizing the archival data of Chandra, we identify three AGNs at $z=$1.06, 2.09, and 2.84 among the 180 millimeter sources securely detected in the ALCS (of which 155 are inside the coverage of Chandra). The X-ray spectral analysis shows that two AGNs are not significantly absorbed ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2} < 23$), while the other shows signs of moderate absorption ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2}\sim 23.5$). We also perform spectral energy distribution (SED) modelling of X-ray to millimeter photometry. We find that our X-ray AGN sample shows both high mass accretion rates (intrinsic 0.5--8 keV X-ray luminosities of ${\sim}10^{\text{44--45}}\,\mathrm{erg\ s^{-1}}$) and star-formation rates (${\gtrsim}100\,M_{\odot}\,\mathrm{yr}^{-1}$). This demonstrates that a wide-area survey with ALMA and Chandra can selectively detect intense growth of both galaxies and supermassive black holes (SMBHs) in the high-redshift universe., Comment: 14 pages, 3 figures, 2 tables

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)., Obtaining high-resolution images at centimeter-or-longer wavelengths is vital for understanding the physics of jets. We reconstructed images from the M87 22 GHz data observed with the East Asian VLBI Network (EAVN) by using the regularized maximum likelihood (RML) method, which is different from the conventional imaging method CLEAN. Consequently, a bright core and jet extending about 30 mas to the northwest were detected with a higher resolution than in the CLEAN image. The width of the jet was 0.5 mas at 0.3 mas from the core, consistent with the width measured in the 86 GHz image in the previous study. In addition, three ridges were able to be detected at around 8 mas from the core, even though the peak-to-peak separation was only 1.0 mas. This indicates that the RML image’s spatial resolution is at least 30% higher than that of the CLEAN image. This study is an important step for future multi-frequency and high-cadence observations of the EAVN to discuss the more detailed structure of the jet and its time variability. © 2023 by the authors. Licensee MDPI, Basel, Switzerland., This research is funded by the following: JSPS (Japan Society for the Promotion of Science) Grant in Aid for Scientific Research (KAKENHI) (A) 22H00157 and (B) 18KK0090 (K.H.). K.H. is also funded by the Mitsubishi Foundation (201911019). Y.C. is funded by the China Postdoctoral Science Foundation (2022M712084). K.A. is financially supported by grants from the National Science Foundation (AST-1935980, AST-2034306, AST-2107681, AST-2132700, OMA-2029670). Y.M. is supported by the National Natural Science Foundation of China (12273022) and the Shanghai pilot program of international scientists for basic research (22JC1410600). R.-S.L. is supported by the Max Planck Partner Group of the MPG and the CAS, the Key Program of the NSFC (No. 11933007), the Key Research Program of Frontier Sciences, CAS (No. ZDBS-LY-SLH011), and the Shanghai Pilot Program for Basic Research—CAS, Shanghai Branch (No. JCYJ-SHFY-2022-013). L.C. is supported by the CAS “Light of West China” Program (No. 2021-XBQNXZ-005) and the NSFC (No. U2031212 and 61931002)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

Mrk 501 is one of the most prominent TeV-emitting blazars and belongs to the class of high synchrotron peaked (HSP) blazars. The Doppler factors derived from the jet kinematics are much too low to provide sufficient beaming for the detected high-energy emission (the so-called Lorentz factor crisis). This BL Lac object is also a prime example of a misaligned AGN with an approximately 90∘ difference in orientation between the inner parsec-scale jet and the kpc-scale jet structure. We have performed a detailed analysis of the pc-scale jet kinematics, based on 23 years of VLBA observations (at 15 GHz) and find, in addition to robustly consolidating the already claimed stationary jet features and a hinted absence of component ejections, a significant drift of the outer nuclear jet. The two outermost jet features move with somewhat higher but still subluminal speeds. Albeit, they move orthogonally to the inner jet, which itself does not partake in the drifting motion. The effect of this intriguing kinematics is that the jet appears strongly curved at first (1995) but then appears to straighten out (2018). To our knowledge, this is the first time that the orthogonal swing of just the outer part of a nuclear jet has been observed. We discuss the possible physical nature of this turning maneuver. In addition, we report evidence for jet emission, which most likely originates in a spine–sheath structure.

Les galaxies centrales d'amas de galaxies constituent un environnement particulier pouvant parfois être entouré, dans le domaine optique, d'un système filamentaire complexe et étendu. L'étude de ces structures permet de mieux comprendre le phénomène de rétroaction impliqué au sein de ces galaxies et lié à la présence d'un trou noir supermassif en leur centre. La formation de jets et de bulles remplis d'émission radio conduit à réchauffer et sculpter le milieu intra-amas environnant. Ce réchauffement empêche ainsi le refroidissement du gaz intra-amas et donc la formation stellaire. Les filaments visibles dans le domaine optique ne constituent qu'une partie de la structure multiphasique qui entoure la galaxie centrale d'amas. En effet, plusieurs observations en rayons X du gaz intra-amas et radio du gaz moléculaire montrent clairement des corrélations spatiales entre toutes ces types d'émissions. Néanmoins, plusieurs points restent encore incertains concernant ces nébuleuses filamentaires. Deux modèles principaux s'opposent ainsi pour tenter d'expliquer l'origine de leur formation et le phénomène d'ionisation du gaz n'est toujours pas déterminé avec certitude. Dès lors, l'étude de la nébuleuse filamentaire entourant la galaxie centrale de l’amas de Persée, NGC 1275, au moyen d'observations à très haute résolution spectrale à l'aide de l'instrument SITELLE (Spectromètre imageur à transformée de Fourier pour l’étude en long et en large de raies d’émission), se révèle fondamentale. Ce spectromètre imageur à transformée de Fourier installé au télescope Canada-France-Hawaï dispose de caractéristiques exceptionnelles nous permettant d'étudier la nébuleuse filamentaire de NGC 1275 dans son entièreté. En effet, le champ de vue extrêmement large de SITELLE ($11' \times 11'$) ainsi que sa capacité d'atteindre de très hautes résolutions spectrales en font un atout de choix pour l'étude de telle structure. Dans ce mémoire, nous avons analysé de nouvelles observations de NGC 1275 obtenues avec SITELLE, à une très haute résolution spectrale de $R = \lambda/\Delta\lambda = 7000$. L'analyse de ces observations a permis de renouveler les cartes de vitesse, flux et dispersion en vitesse au sein de la nébuleuse filamentaire, démontrant ainsi que la région centrale semble plus dynamique qu'anticipée auparavant. De plus, grâce à la très haute résolution spectrale atteinte au sein de ces données, une analyse détaillée des raies d'émission de [SII] a pu être menée, révélant dès lors plus d'informations sur la densité du gaz au sein des filaments. L'étude de ratio de raies permet également de mieux cerner le mécanisme d'ionisation ayant lieu au sein de cette structure. Finalement, cette étude de données à très haute résolution spectrale des filaments permettra à terme d'obtenir les diagrammes BPT offrant ainsi une meilleure compréhension du phénomène d'ionisation. Une étude sera également menée sur les multiples composantes en vitesse visible localement dans la région centrale des filaments et pouvant être résolues. Enfin, ces données serviront de base pour les futures observations en rayon X de l'instrument XRISM (\textit{X-Ray Imaging and Spectroscopy Mission})., The central cluster galaxies constitute a particular environment that can sometimes be surrounded, in the optical domain, by a complex and extended filamentary system. The study of these structures makes it possible to better understand the feedback phenomenon involved within these galaxies and linked to the presence of a supermassive black hole in their center. The formation of jets, streams and bubbles filled with radio emissions that it entails leads to heating and sculpting the surrounding intra-cluster medium. This heating thus prevents the cooling of the gas by emission and therefore the formation of stars. Thus, the filaments visible in the optical domain are only part of the multiphase structure that surrounds the central cluster galaxy. Indeed, several X-ray and radio observations clearly show spatial correlations between all these types of emissions. Nevertheless, several points still remain uncertain concerning filamentary nebulae. Two main models thus oppose each other in an attempt to explain the origin of their formation, either through precipitation or lifted up in the wake of radio bubbles, and the phenomenon of gas ionization is still not determined with certainty. Therefore, the study of the filamentary nebula surrounding the central cluster galaxy of the Perseus cluster, NGC 1275, by means of very high spectral resolution observations using the SITELLE instrument (Spectromètre imageur à transformée de Fourier pour l’étude en long et en large de raies d’émission), can yield fundamental results that will shed light on the origin and evolution of these filamentary nebulae. SITELLE is a Fourier transform imaging spectrometer installed at the Canada-France-Hawaii telescope that has exceptional characteristics allowing us to study the filamentary nebula of NGC 1275 in its entirety. Indeed, the extremely wide field of view of SITELLE ($11' \times 11'$) as well as its capacity to reach very high spectral resolutions make it an instrument of choice for the study of such structures. Here, we present the analysis of new observations of NGC 1275 taken with SITELLE at very high spectral resolution of $R = \lambda/\Delta\lambda = 7000$. The analysis of these observations has thus made it possible to produce new maps of velocity, flux and velocity dispersion within the filamentary nebula, thus demonstrating that the central region seems more dynamic than previously anticipated. In addition, thanks to the very high spectral resolution achieved within these data, a detailed analysis of the emission lines of [SII] could be carried out, revealing more information on the density of the gas within the filaments. The study of line ratios also makes it possible to better understand the ionization mechanism taking place within this structure. Finally, this study of very high spectral resolution data from the filaments will ultimately make it possible to obtain BPT diagrams, thus offering a better understanding of the ionization phenomenon. The multiple velocity components, locally visible and resolved in the central region of the filaments, will also be studied. Finally, these data will serve as a basis for future X-ray observations from the XRISM (\textit{X-Ray Imaging and Spectroscopy Mission}) instrument.

Galaxy evolution is an interplay of physical processes across a wide range of cosmological size scales, from star formation and black hole growth on sub-pc scales, to interactions with their environments on Mpc scales. The region surrounding individual galaxies within their host halos is known as the Circumgalactic Medium (CGM), and connects galaxies to the wider Intergalactic Medium (IGM). The CGM acts as both a reservoir of inflowing gas and a repository for outflowing gas as it is transported outwards via galactic feedback. Quasar absorption line surveys have revealed the CGM to be a complex, multiphase environment in which ions tracing cool and hot gas are present within the same absorber systems. Cosmological simulations are a powerful tool for building a theoretical understanding of these interconnected processes and resulting observations. They provide a 3D view of galaxies and their host halos, in which we intrinsically know the physical conditions of the constituent dark matter and baryons. As such, simulations are useful both for testing galaxy evolution models against the real universe, and for interpreting complex observations in a physical context. In this thesis I present detailed comparisons of simulations to observations of star formation and quenching in galaxies, and of absorbers in galactic halos in an effort to constrain physical models. I use Simba, a suite of state of the art cosmological simulations with realistic sub-grid physical models based on high resolution zoom simulations, including novel treatments of dust evolution and of black hole growth and feedback. I investigate the nature of gas in galaxies and their halos, and show comparisons with observations. In addition, I isolate the impacts of galactic feedback and ionising radiation on the results by varying elements of the input physical models. In Chapter 3, I present radial profiles of star forming and green valley galaxies in Simba at z=0 and compare with observations of MaNGA spatially resolved spectroscopy. My analysis shows strong central depressions in star formation rate (SFR), specific SFR (sSFR), and gas fraction in Simba's green valley galaxies and massive star-forming systems, qualitatively as] observed, owing to Active Galactic Nuclei (AGN) X-ray feedback, which pushes central gas radially outwards. These effects are less pronounced at higher redshift, owing to less powerful AGN feedback. I also present a comparison of galaxy half light radii to observations at various redshifts, finding that predictions for star-forming galaxy sizes are accurate but that quenched galaxies are impacted by numerical heating. In Chapter 4, I characterise the low redshift CGM in Simba and examine the impact of differing feedback prescriptions. Low mass galaxies live in multiphase, diverse halos, whereas high mass galaxies live in halos dominated by hot gas. Halo baryon fractions are generally < 50% of the cosmic fraction due to stellar feedback at low masses, and 'jet-mode' AGN feedback at high masses. I present a comparison of absorption statistics to the COS-Halos and COS-Dwarfs surveys: Simba reproduces HI absorption well around star forming galaxies and broadly reproduces absorption of selected metal lines, including the observed dichotomy in OVI absorption between star forming and quenched galaxies. These predictions of metal line absorption are sensitive to the choice of photo-ionising background. Varying the galactic feedback prescription shows that stellar feedback enriches the CGM, while AGN feedback sets the gas temperature phase. In Chapter 5 I extend this analysis with a theoretical perspective of the CGM in Simba using a sample of CGM absorbers from a representative sample of Simba galaxies, selected across a range of stellar masses and sSFR. Absorbers are more abundant around low mass, star forming galaxies; the CGM of green valley galaxies is more similar to that of quenched galaxies. The absorber overdensity depends on the sSFR of the galaxy, while the absorber temperature is set by galaxy stellar mass. Absorption from low ions arises from cold, dense CGM gas, whilst absorption from higher ions traces hotter, more diffuse gas. I also examine the proportion of absorption arising from collisionally ionised gas, and from gas that is associated with satellite galaxies. Finally, in Chapter 6 I develop a tree-based machine learning mapping between the observable properties and the underlying physical conditions of the absorbers in the CGM absorber sample from Chapter 5. Such a mapping has the potential to be used to interpret CGM observations within a full cosmological context, assuming the Simba galaxy evolution model.

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq We present an analysis of gas ionisation and kinematics for nine Red Geysers selected from the MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) survey of SDSS-IV (Sloan Digital Sky Survey-IV) and observed with the GMOS (Gemini Multi-Object Spectrographs) integral field unit (IFU) from the Gemini North telescope. Red Geysers are quiescent galaxies with galactic scale ionised outflows, likely due to low-luminosity Active Galactic Nuclei (AGN). The GMOS-IFU observations were obtained for the nuclear region of these galaxies in the inner ∼1–3 kpc. The main goals of this work are the investigation of the gas ionisation source and the presence of biconical outflows originating in a precessing accretion disc in Red Geyser galaxies. The emission-line ratios suggest the presence of Seyfert/LINER (LowIonisation Nuclear Emission Region) nuclei in all sources. Two galaxies show Hα equivalent width (Hα EW) larger than 3 Å (indicative of AGN ionisation) within an aperture 2.5′′ of diameter (1.3–3.7 kpc at the distance of galaxies) for MaNGA data, while with the higher resolution GMOS data, four galaxies present Hα EW> 3 Å within an aperture equal to the angular resolution (0.3–0.9 kpc). For two objects with GMOS-IFU data, the Hα EW is lower than 3 Å but larger than 1.5 Å, most probably due to a faint AGN. The spatially resolved electron density maps show values between 100–3000 cm−3 and are consistent with those determined for the NLR (Narrow-Line Region) and outflows in other studies. The [N II]λ6583 emission-line profiles are asymmetrical for the six galaxies with extended emission, with blue wings on the redshifted side of the velocity field and red wings on the blueshifted side. A biconical outflow can cause these asymmetries. The large (MaNGA) and the nuclear scale (GMOS-IFU) gas velocity fields are misaligned, with a kinematic position angle difference between 12◦–60◦ determined using the FIT KINEMATICS PA method and 13◦–49◦ when calculated the mean value of radial profiles of the kinematic position angle. Furthermore, the variation of radial profiles of the kinematic position angle with distance from the nuclear region is continuous when we combine the values determined from the GMOS-IFU and MaNGA velocity fields. Besides that, the observed variation in the kinematic position angle is consistent with outflows originating in a precessing accretion disc as proposed for the Akira galaxy, the prototype of the Red Geyser class. Thus, our results support previous indications that the gas in Red Geysers is ionised by an AGN, at least in their central region, with the presence of outflows, likely originating in a precessing accretion disc. Apresentamos uma análise da ionização e da cinemática do gás para nove Red Geysers selecionadas do levantamento MaNGA (Mapping Near Galaxies at Apache Point Observatory) do SDSS-IV (Sloan Digital Sky Survey-IV) e observadas com a unidade de campo integral (IFUIntegral Field Unit) do GMOS (Gemini Multi-Object Spectrographs ) do telescópio Gemini Norte. As Red Geysers são galáxias quiescentes com outflows de gás ionizado vistos em escalas galácticas, provavelmente oriundos de núcleos galácticos ativos (AGN-Active Galactic Nuclei) de baixa luminosidade. As observações do GMOS-IFU foram obtidas para a região nuclear dessas galáxias no interior de ∼1–3 kpc. Os principais objetivos desse trabalho são investigar a fonte de ionização do gás e a presença de outflows bicônicos originados em um disco de acreção em precessão em galáxias Red Geysers. As razões das linhas de emissão sugerem a presença de núcleos Seyfert/LINER (Low- Ionisation Nuclear Emission Region) em todas as fontes. Duas galáxias mostram largura equivalente Hα (Hα EW) maior que 3 Å (indicativo de ionização por AGN) dentro de uma abertura de 2.5′′ de diâmetro (1.3–3.7 kpc à distância das galáxias) para os dados MaNGA, enquanto com os dados do GMOS de maior resolução, quatro galáxias apresentam Hα EW> 3 Å dentro de uma abertura igual à resolução angular (0.3–0.9 kpc). Para dois objetos com dados do GMOS-IFU, o valor de Hα EW é menor que 3 Å mas maior que 1.5 Å, provavelmente devido a um AGN fraco. Os mapas de densidade eletrônica resolvidos espacialmente mostram valores entre 100–3000 cm−3 e são consistentes com aqueles determinados para a NLR (Narrow-Line Region) e outflows em outros estudos. Os perfis da linha de emissão do [N II]λ6583 são assimétricos para as seis galáxias com emissão estendida, com asas azuis no lado em redshift do campo de velocidade e asas vermelhas no lado em blueshift. Um outflow bicônico pode causar essas assimetrias. Os campos de velocidade do gás em escala galáctica (MaNGA) e escala nuclear (GMOS-IFU) estão desalinhados, com uma diferença do ângulo de posição cinemático entre 12◦–60◦ determinada usando o método FIT KINEMATICS PA e entre 13◦–49◦ quando calculado o valor médio dos perfis radiais do ângulo de posição cinemático. Além disso, a variação dos perfis radiais do ângulo de posição cinemático com a distância ao núcleo é contínua quando combinamos os valores determinados a partir dos campos de velocidades do GMOS-IFU e do MaNGA. A variação observada no ângulo de posição cinemático é consistente com ventos originados em um disco de acreção em precessão como proposto para a galáxia Akira, o protótipo da classe de Red Geysers. Assim, nossos resultados corroboram os indicativos anteriores de que o gás em Red Geysers é ionizado por um AGN, pelo menos em sua região central, com a presença de outflows, provavelmente originados em um disco de acreção em precessão.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)., The next-generation Event Horizon Telescope (ngEHT) will provide us with the best opportunity to investigate supermassive black holes (SMBHs) at the highest possible resolution and sensitivity. With respect to the existing Event Horizon Telescope (EHT) array, the ngEHT will provide increased sensitivity and uv-coverage (with the addition of new stations), wider frequency coverage (from 86 GHz to 345 GHz and higher), finer resolution (, R.L., J.L.G., and R.D. acknowledge financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709), from the Spanish Ministerio de Economía y Competitividad and Ministerio de Ciencia e Innovación (grants AYA2016-80889-P, PID2019-108995GB-C21), the Consejería de Economía, Conocimiento, Empresas y Universidad of the Junta de Andalucía (grant P18-FR-1769), the Consejo Superior de Investigaciones Científicas (grant 2019AEP112). A.P.M. and S.G.J. acknowledge financial support from NASA Fermi Guest Investigator grants 80NSSC20K1567 and 80NSSC22K1571., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

We present a case for significantly enhancing the utility and efficiency of the ngEHT by incorporating an additional 86 GHz observing band. In contrast to 230 or 345 GHz, weather conditions at the ngEHT sites are reliably good enough for 86 GHz to enable year-round observations. Multi-frequency imaging that incorporates 86 GHz observations would sufficiently augment the ($u,v$) coverage at 230 and 345 GHz to permit detection of the M87 jet structure without requiring EHT stations to join the array. The general calibration and sensitivity of the ngEHT would also be enhanced by leveraging frequency phase transfer techniques, whereby simultaneous observations at 86 GHz and higher-frequency bands have the potential to increase the effective coherence times from a few seconds to tens of minutes. When observation at the higher frequencies is not possible, there are opportunities for standalone 86 GHz science, such as studies of black hole jets and spectral lines. Finally, the addition of 86 GHz capabilities to the ngEHT would enable it to integrate into a community of other VLBI facilities $-$ such as the GMVA and ngVLA $-$ that are expected to operate at 86 GHz but not at the higher ngEHT observing frequencies., Comment: 23 pages, 10 figures

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiere, The Fermi Large Area Telescope (LAT) lightcurve repository (LCR) is a publicly available, continually updated library of gamma-ray lightcurves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality lightcurves binned on timescales of 3, 7, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 yr of Fermi-LAT observations. The repository consists of lightcurves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multimessenger communities by allowing users to search LAT data quickly to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal, M.N. and J.V. acknowledge that the material is based upon work supported by NASA under award number 80GSFC21M0002. D.K. and M.N. acknowledge support to this work from NASA Fermi GI Program under grant number 80NSSC23K0242. A.B. is supported by the NASA Postdoctoral Program at NASA Goddard Space Flight Center, administered by Oak Ridge Associated Universities. INFN and ASI personnel performed in part under ASI-INFN Agreements No. 2021-43-HH.0. Work at NRL is supported by NASA. The Fermi-LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat à l’Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d’Études Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515

We present an analysis of the BVRI photometry of the blazar BL Lacertae on diverse timescales from 2020 mid-July to mid-September. We have used 11 different optical telescopes around the world and have collected data over 84 observational nights. The observations cover the onset of a new activity phase of BL Lacertae that started in 2020 August (termed as the 2020 August flare by us), and the analysis is focused on the intranight variability. On short-term timescales, (i) flux varied with ∼2.2 mag in the R band, (ii) the spectral index was found to be weakly dependent on the flux (i.e., the variations could be considered mildly chromatic), and (iii) no periodicity was detected. On intranight timescales, BL Lacertae was found to predominantly show bluer-when-brighter chromatism. We also found two cases of significant interband time lags of the order of a few minutes. The duty cycle of the blazar during the 2020 August flare was estimated to be quite high (∼90% or higher). We decomposed the intranight light curves into individual flares and determined their characteristics. On the basis of our analysis and assuming the turbulent jet model, we determined some characteristics of the emitting regions: Doppler factor, magnetic field strength, electron Lorentz factor, and radius. The radii determined were discussed in the framework of the Kolmogorov theory of turbulence. We also estimated the weighted mean structure function slope on intranight timescales, related it to the slope of the power spectral density, and discussed it with regard to the origin of intranight variability.

Active galactic nuclei (AGN) have been observed as far as redshift z~7. They are crucial in investigating the early Universe as well as the growth of supermassive black holes at their centres. Radio-loud AGN with their jets seen at a small viewing angle are called blazars and show relativistic boosting of their emission. Thus, their apparently brighter jets are easier to detect in the high-redshift Universe. DES J014132.4-542749.9 is a radio-luminous but X-ray weak blazar candidate at z = 5. We conducted high-resolution radio interferometric observations of this source with the Australian Long Baseline Array at 1.7 and 8.5 GHz. A single, compact radio emitting feature was detected at both frequencies with a flat radio spectrum. We derived the milliarcsecond-level accurate position of the object. The frequency dependence of its brightness temperature is similar to that of blazar sources observed at lower redshifts. Based on our observations, we can confirm its blazar nature. We compared its radio properties with those of two other similarly X-ray-weak and radio-bright AGN, and found that they show very different relativistic boosting characteristics., Comment: 8 pages, 4 figures, accepted for publication in PASA

Full list of authors: Amaro-Seoane, Pau; Andrews, Jeff; Sedda, Manuel Arca; Askar, Abbas.; Baghi, Quentin; Balasov, Razvan; Bartos, Imre; Bavera, Simone S.; Bellovary, Jillian; Berry, Christopher P. L.; Berti, Emanuele; Bianchi, Stefano; Blecha, Laura; Blondin, Stephane; Bogdanovic, Tamara; Boissier, Samuel; Bonetti, Matteo; Bonoli, Silvia; Bortolas, Elisa; Breivik, Katelyn; Capelo, Pedro R.; Caramete, Laurentiu; Cattorini, Federico; Charisi, Maria; Chaty, Sylvain; Chen, Xian; Chruslinska, Martyna; Chua, Alvin J. K.; Church, Ross; Colpi, Monica; D'Orazio, Daniel; Danielski, Camilla; Davies, Melvyn B.; Dayal, Pratika; De Rosa, Alessandra; Derdzinski, Andrea; Destounis, Kyriakos; Dotti, Massimo; Dutan, Ioana; Dvorkin, Irina; Fabj, Gaia; Foglizzo, Thierry; Ford, Saavik; Fouvry, Jean-Baptiste; Franchini, Alessia; Fragos, Tassos; Fryer, Chris; Gaspari, Massimo; Gerosa, Davide; Graziani, Luca; Groot, Paul; Habouzit, Melanie; Haggard, Daryl; Haiman, Zoltan; Han, Wen-Biao; Istrate, Alina; Johansson, Peter H.; Khan, Fazeel Mahmood; Kimpson, Tomas; Kokkotas, Kostas; Kong, Albert; Korol, Valeriya; Kremer, Kyle; Kupfer, Thomas; Lamberts, Astrid; Larson, Shane; Lau, Mike; Liu, Dongliang; Lloyd-Ronning, Nicole; Lodato, Giuseppe; Lupi, Alessandro; Ma, Chung-Pei; Maccarone, Tomas; Mandel, Ilya; Mangiagli, Alberto; Mapelli, Michela; Mathis, Stephane; Mayer, Lucio; McGee, Sean; McKernan, Berry; Miller, M. Coleman; Mota, David F.; Mumpower, Matthew; Nasim, Syeda S.; Nelemans, Gijs; Noble, Scott; Pacucci, Fabio; Panessa, Francesca; Paschalidis, Vasileios; Pfister, Hugo; Porquet, Delphine; Quenby, John; Ricarte, Angelo; Roepke, Friedrich K.; Regan, John; Rosswog, Stephan; Ruiter, Ashley; Ruiz, Milton; Runnoe, Jessie; Schneider, Raffaella; Schnittman, Jeremy; Secunda, Amy; Sesana, Alberto; Seto, Naoki; Shao, Lijing; Shapiro, Stuart; Sopuerta, Carlos; Stone, Nicholas C.; Suvorov, Arthur; Tamanini, Nicola; Tamfal, Tomas; Tauris, Thomas; Temmink, Karel; Tomsick, John; Toonen, Silvia; Torres-Orjuela, Alejandro; Toscani, Martina; Tsokaros, Antonios; Unal, Caner; Vazquez-Aceves, Veronica; Valiante, Rosa; van Putten, Maurice; van Roestel, Jan; Vignali, Christian; Volonteri, Marta; Wu, Kinwah; Younsi, Ziri; Yu, Shenghua; Zane, Silvia; Zwick, Lorenz; Antonini, Fabio; Baibhav, Vishal; Barausse, Enrico; Bonilla Rivera, Alexander; Branchesi, Marica; Branduardi-Raymont, Graziella; Burdge, Kevin; Chakraborty, Srija; Cuadra, Jorge; Dage, Kristen; Davis, Benjamin; de Mink, Selma E.; Decarli, Roberto; Doneva, Daniela; Escoffier, Stephanie; Gandhi, Poshak; Haardt, Francesco; Lousto, Carlos O.; Nissanke, Samaya; Nordhaus, Jason; O'Shaughnessy, Richard; Portegies Zwart, Simon; Pound, Adam; Schussler, Fabian; Sergijenko, Olga; Spallicci, Alessandro; Vernieri, Daniele; Vigna-Gomez, Alejandro.-- This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/., The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it will offer unique opportunities to address many key astrophysical questions in a completely novel way. The synergy with ground-based and space-born instruments in the electromagnetic domain, by enabling multi-messenger observations, will add further to the discovery potential of LISA. The next decade is crucial to prepare the astrophysical community for LISA’s first observations. This review outlines the extensive landscape of astrophysical theory, numerical simulations, and astronomical observations that are instrumental for modeling and interpreting the upcoming LISA datastream. To this aim, the current knowledge in three main source classes for LISA is reviewed; ultra-compact stellar-mass binaries, massive black hole binaries, and extreme or interme-diate mass ratio inspirals. The relevant astrophysical processes and the established modeling techniques are summarized. Likewise, open issues and gaps in our understanding of these sources are highlighted, along with an indication of how LISA could help making progress in the different areas. New research avenues that LISA itself, or its joint exploitation with upcoming studies in the electromagnetic domain, will enable, are also illustrated. Improvements in modeling and analysis approaches, such as the combination of numerical simulations and modern data science techniques, are discussed. This review is intended to be a starting point for using LISA as a new discovery tool for understanding our Universe. © The Author(s) 2023, corrected publication 2023., P. Dayal acknowledges support from the European Research council (ERC-717001) and from the Netherlands Research Council NWO (016.VIDI.189.162). P.H. Johansson acknowledges the support from the European Research Council (ERC-818930). S. Toonen acknowledges support from the Netherlands Research Council NWO (VENI 639.041.645 Grants) C. Unal is supported by European Structural and Investment Funds and the Czech Ministry of Education, Youth and Sports (Project CoGraDS - CZ.02.1.01/0.0/0.0/15_003/0000437). S. Chaty acknowledges the LabEx UnivEarthS for the funding of Interface project I10 “From binary evolution towards merging of compact objects”. A. De Rosa acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.O E. Berti is supported by NSF Grants No. PHY-1912550 and AST-2006538, NASA ATP Grants No. 17-ATP17-0225 and 19-ATP19-0051, NSF-XSEDE Grant No. PHY-090003, and NSF Grant PHY-20043. D. Gerosa is supported by European Union’s H2020 ERC Starting Grant No. 945155–GWmining, Leverhulme Trust Grant No. RPG-2019-350 and Royal Society Grant No. RGS-R2-202004. T. Bogdanovic acknowledges support by the NASA award No. 80NSSC19K0319 and by the NSF award AST-1908042. D. Porquet acknowledges funding support from CNES. C. Danielski acknowledges financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709) B.L. Davis acknowledges support from Tamkeen under the NYU Abu Dhabi Research Institute Grant CAP3. F. Pacucci acknowledges support from a Clay Fellowship by the SAO and from the Black Hole Initiative, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation. A.J. Ruiter acknowledges support from the Australian Research Council Future Fellowship Grant FT170100243. V. Paschalidis is supported by NSF Grant PHY-1912619 and NASA Grant 80NSSC20K1542 to the University of Arizona, and NSF-XSEDE Grant TG-PHY190020. D. Haggard acknowledges support from the NSERC Discovery Grant and Canada Research Chairs programs, and the Bob Wares Science Innovation Prospectors Fund. M. Toscani acknowledges European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 823823 (RISE DUSTBUSTERS project) and COST Action CA16104 - Gravitational waves, black holes and fundamental physics, supported by COST (European Cooperation in Science and Technology). M. Chruslinska, A. Istrate and G. Nelemans acknowledge support from Netherlands Research Council NWO. T. Fragos and S. Bavera acknowledge support from a Swiss National Science Foundation Professorship Grant (project numbers PP00P2_176868 and PP00P2_211006)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

The nature of dark matter (DM) is one of the most relevant questions in modern astrophysics. We present a brief overview of recent results that inquire into the possible fermionic quantum nature of the DM particles, focusing mainly on the interconnection between the microphysics of the neutral fermions and the macrophysical structure of galactic halos, including their formation both in the linear and non-linear cosmological regimes. We discuss the general relativistic Ruffini–Argüelles–Rueda (RAR) model of fermionic DM in galaxies, its applications to the MilkyWay, the possibility that the Galactic center harbors a DM core instead of a supermassive black hole (SMBH), the S-cluster stellar orbits with an in-depth analysis of the S2’s orbit including precession, the application of the RAR model to other galaxy types (dwarf, elliptic, big elliptic, and galaxy clusters), and universal galaxy relations. All the above focus on the model parameters’ constraints most relevant to the fermion mass. We also connect the RAR model fermions with particle physics DM candidates, self-interactions, and galactic observable constraints. The formation and stability of core–halo galactic structures predicted by the RAR model and their relations to warm DM cosmologies are also addressed. Finally, we provide a brief discussion of how gravitational lensing, dynamical friction, and the formation of SMBHs can also probe the DM’s nature., Instituto de Astrofísica de La Plata

We present a narrowband [O III] imaging survey of 111 AGN hosts and 17 merging-galaxy systems, in search of distant extended emission-line regions (EELRs) around AGN (either extant or faded). Our data reach deeper than detection from the broadband SDSS data, and cover a wider field than some early emission-line surveys used to study extended structure around AGN. Spectroscopic followup confirms two new distant AGN-ionized clouds, in the merging systems NGC 235 and NGC 5514, projected at 26 and 75 kpc from the nuclei (respectively). We also recover the previously-known region in NGC 7252. These results strengthen the connection between EELRs and tidal features; kinematically quiescent distant EELRs are virtually always photoionized tidal debris. We see them in ~10% of the galaxies in our sample with tidal tails. Energy budgets suggest that the AGN in NGC 5514 has faded by >3 times during the extra light-travel time ~250,000 years from the nucleus to the cloud and then to the observer; strong shock emission in outflows masks the optical signature of the AGN. For NGC 235 our data are consistent with but do not unequivocally require variation over ~85,000 years. In addition to these very distant ionized clouds, luminous and extensive line emission within four galaxies - IC 1481, ESO 362-G08, NGC 5514, and NGC 7679. IC 1481 shows apparent ionization cones, a rare combination with its LINER AGN spectrum. In NGC 5514, we measure a 7-kpc shell expanding at ~370 km/s west of the nucleus., Accepted for MNRAS

We present the discovery and preliminary characterisation of two high-redshift gravitationally lensed quasar systems in Gaia Data Release 2 (DR2). Candidates with multiple close-separation Gaia detections and quasar-like colours in WISE, Pan-STARRS, and DES are selected for follow-up spectroscopy with the New Technology Telescope. We confirm DES J215028.71−465251.3 as a $z$ = 4.130 ± 0.006 asymmetric, doubly imaged lensed quasar system and model the lensing mass distribution as a singular isothermal sphere. The system has an Einstein radius of 1.202 ± 0.005 arcsec and a predicted time delay of ∼122.0 d between the quasar images, assuming a lensing galaxy redshift of $z$ = 0.5, making this a priority system for future optical monitoring. We confirm PS J042913.17+142840.9 as a $z$ = 3.866 ± 0.003 four-image quasar system in a cusp configuration, lensed by two foreground galaxies. The system is well modelled using a singular isothermal ellipsoid for the primary lens and a singular isothermal sphere for the secondary lens with Einstein radii 0.704 ± 0.006 and 0.241 ± 0.030 arcsec, respectively. A maximum predicted time delay of 9.6 d is calculated, assuming lensing galaxy redshifts of $z$ = 1.0. Furthermore, PS J042913.17+142840.9 exhibits a large flux ratio anomaly, up to a factor of 2.66 ± 0.37 in i band, that varies across optical and near-infrared wavelengths. We discuss LSST and its implications for future high-redshift lens searches and outline an extension to the search using supervised machine learning techniques.

The origin and evolution of galaxies are closely linked to many different physical phenomena. Among them, the most important one is the environment they reside in. Isolated and cluster member galaxies indeed are affected by different forces which affect their evolution. The main concern of this thesis is to understand such forces and how they are related to galaxy evolution. Therefore, this thesis covers various topics including black hole mass calculations, the black hole mass-stellar velocity dispersion relation, the nature of AGN emission in galaxy clusters and field galaxies, a detailed investigation of X-ray and optical galaxy overdensity phenomenon, and the dynamical processes in pre-merging galaxy clusters.

The origin and evolution of galaxies are closely linked to many different physical phenomena. Among them, the most important one is the environment they reside in. Isolated and cluster member galaxies indeed are affected by different forces which affect their evolution. The main concern of this thesis is to understand such forces and how they are related to galaxy evolution. Therefore, this thesis covers various topics including black hole mass calculations, the black hole mass-stellar velocity dispersion relation, the nature of AGN emission in galaxy clusters and field galaxies, a detailed investigation of X-ray and optical galaxy overdensity phenomenon, and the dynamical processes in pre-merging galaxy clusters.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)., The next-generation Event Horizon Telescope (ngEHT) will be a significant enhancement of the Event Horizon Telescope (EHT) array, with ∼10 new antennas and instrumental upgrades of existing antennas. The increased -coverage, sensitivity, and frequency coverage allow a wide range of new science opportunities to be explored. The ngEHT Analysis Challenges have been launched to inform the development of the ngEHT array design, science objectives, and analysis pathways. For each challenge, synthetic EHT and ngEHT datasets are generated from theoretical source models and released to the challenge participants, who analyze the datasets using image reconstruction and other methods. The submitted analysis results are evaluated with quantitative metrics. In this work, we report on the first two ngEHT Analysis Challenges. These have focused on static and dynamical models of M87* and Sgr A* and shown that high-quality movies of the extended jet structure of M87* and near-horizon hourly timescale variability of Sgr A* can be reconstructed by the reference ngEHT array in realistic observing conditions using current analysis algorithms. We identify areas where there is still room for improvement of these algorithms and analysis strategies. Other science cases and arrays will be explored in future challenges. © 2023 by the authors. Licensee MDPI, Basel, Switzerland., This research was supported by NSF grants AST-1935980 and AST-2034306. This work was supported by the Black Hole Initiative at Harvard University, made possible through the support of grants from the Gordon and Betty Moore Foundation and the John Templeton Foundation. The opinions expressed in this publication are those of the author(s) and do not necessarily reflect the views of the Moore or Templeton Foundations. Hendrik Müller received financial support for this research from the International Max Planck Research School (IMPRS) for Astronomy and Astrophysics at the Universities of Bonn and Cologne. This research is supported by the DFG research grant “Jet physics on horizon scales and beyond” (Grant No. FR 4069/2-1), the ERC synergy grant “BlackHoleCam: Imaging the Event Horizon of Black Holes” (Grant No. 610058) and ERC advanced grant “JETSET: Launching, propagation and emission of relativistic jets from binary mergers and across mass scales” (Grant No. 884631). Jakob Knollmüller acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC 2094—390783311. Razieh Emami acknowledges the support by the Institute for Theory and Computation at the Center for Astrophysics as well as grant numbers 21-atp21-0077, NSF AST-1816420 and HST-GO-16173.001-A for very generous support., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

The study of galaxy evolution hinges on our ability to interpret multi-wavelength galaxy observations in terms of their physical properties. To do this, we rely on spectral energy distribution (SED) models which allow us to infer physical parameters from spectrophotometric data. In recent years, thanks to the wide and deep multi-waveband galaxy surveys, the volume of high quality data have significantly increased. Alongside the increased data, algorithms performing SED fitting have improved, including better modeling prescriptions, newer templates, and more extensive sampling in wavelength space. We present a comprehensive analysis of different SED fitting codes including their methods and output with the aim of measuring the uncertainties caused by the modeling assumptions. We apply fourteen of the most commonly used SED fitting codes on samples from the CANDELS photometric catalogs at z~1 and z~3. We find agreement on the stellar mass, while we observe some discrepancies in the star formation rate (SFR) and dust attenuation results. To explore the differences and biases among the codes, we explore the impact of the various modeling assumptions as they are set in the codes (e.g., star formation histories, nebular, dust, and AGN models) on the derived stellar masses, SFRs, and A_V values. We then assess the difference among the codes on the SFR-stellar mass relation and we measure the contribution to the uncertainties by the modeling choices (i.e., the modeling uncertainties) in stellar mass (~0.1dex), SFR (~0.3dex), and dust attenuation (~0.3mag). Finally, we present some resources summarizing best practices in SED fitting., 25 pages, 11 figures. Accepted for publication in ApJ

[EN] This thesis is aimed to provide insights into the relevance of feedback processes in galaxies harbouring at its centre an Active Galactic Nucleus (AGN). Feedback is believed to impact the evolution of galaxies by regulating the star formation and AGN activity. In particular, these processes can be triggered by outflows, that are detected with various tracers related to different gas phases (e.g. ionised or hot gas). In this thesis, we focused on the exploration of the processes at the low end of the AGN luminosity function, in particular with Low- Ionisation Nuclear Emission-line Regions (LINERs). These objects are the largest AGN family in the Local Universe, representing more than 60% of the local population (Ho 2008). Their relative faintness make their detection and characterisation more difficult than for other AGN types, although their proximity gives these objects an advantage, since spatially resolved studies can be made. This is specially important for the characterisation of feedback processes, particularly in the search for outflows. During the last 20 years, outflows have been detected in a variety of systems, from starforming galaxies to AGNs. The increasing number of works dedicated to the study of feedback processes seem to conclude that outflows are ubiquitous in both types of galaxies. Many efforts now are dedicated to analysing their properties and evaluating their impact in the evolution of the host galaxy from pc to kpc-scales. However, in the case of AGNs their study has been mainly focused on luminous systems, where outflows are expected to be more powerful and thus easier to detect and characterise. Nevertheless, it remains unclear if outflows are also common or even ubiquitous in LINERs, as this AGN population has been largely unstudied. In this thesis we address this topic with three different methodologies that will be described along the corresponding chapters. Optical spectroscopy of type-2 LINERs. We first present the analysis of long-slit spectroscopic data for nine type-2 LINERs obtained with the Hubble Space Telescope (HST) and the Palomar Survey. This work complements the previous work by Cazzoli et al. (2018) on type-1 LINERs. The objectives are twofold: (i) detect a broad line region component in the Balmer emission lines, and (ii) search for outflows as a broad (σ ≤ 500 km s−1), blueshifted, component in the emission lines. We detected a broad component for 67% of the HST spectra and 25% of the Palomar spectra. As for the outflows, we found that 35% of the type-2 LINERs are good candidates to host them. A search for ionised gas outflows in an Hα imaging atlas of nearby LINERs. We then systematically searched for outflows in a sample of 70 nearby LINERs by analysing the ionised gas distribution in these systems, using proprietary ALFOSC/NOT and archival HST narrow band imaging. We were able to identify the main morphologies of the Hα gas and detect possible outflows as extended gas for 32% of the objects. Afterwards, by combining imaging with kinematic data from the literature, we found that ∼50% of the local LINERs host an outflow in different gas phases. These results indicated that outflows are common in low luminosity AGNs as LINERs. Analysis of the candidate outflows in LINERs with MEGARA/GTC integral field spectroscopic data (IFS). Finally, we used IFS data to confirm or not the outflow candidates identified from the previous two works on a spatially-resolved basis. For that purpose we used MEGARA/GTC data of nine LINERs in three spectral bands in the optical range. We study as a first case the prototypical LINER NGC1052 (complementing with proprietary MUSE/VLT data). We detected in this object an ionised gas outflow probably driven by the jet, propagating in a region of turbulent gas, and triggering kpc-scale bubbles. Then we analysed the other eight objects, finding a kinematical signatures of an ionised gas outflow in four of these LINERs (i.e. 50%). The LINER NGC4438 is the only object in our sample for which we found three resolved kinematical components in all the emission lines with the MEGARA data. These probe the gaseous disc and an outflow with a bubble-like structure, previously detected with high spatial resolution imaging., [ES] Esta tesis tiene como objetivo proporcionar información sobre la relevancia de los procesos de retroalimentación en galaxias que poseen en su centro un núcleo activo de galaxias (AGN en inglés). Se cree que los procesos de retroalimentación afectan a la evolución de las galaxias a través de la regulación de la formación estelar y de la actividad nuclear. En particular, estos procesos se pueden desencadenar por los llamados ‘outflows’, los cuales se detectan usando varios trazadores relacionados con las distintas fases del gas (por ejemplo, gas ionizado o caliente). En esta tesis nos centramos en la exploración de estos procesos en el límite inferior de luminosidad en los AGNs, en particular en las llamadas regiones nucleares de líneas de emisión de baja ionización (LINERs por sus siglas en inglés). Estos objetos son la familia más numerosa de AGNs que encontramos en el Universo Local, representando a más del 60% de la población local (Ho 2008). Su relativa debilidad hace que sean más dificiles de detectar y caracterizar que otros tipos de AGNs, aunque su proximidad les da la ventaja de permitir realizar estudios espacialmente resueltos. Esto aplica especialmente para el análisis de procesos de retroalimentación y, en particular, para la búsqueda de ‘outflows’. Durante los últimos 20 años se han detectado ‘outflows’ en una gran variedad de sistemas, tanto galaxias con formación estelar como en AGNs. El aumento del número de trabajos dedicados al estudio de procesos de retroalimentación parecen concluir que los ‘outflows’ aparecen de manera ubicua en los sistemas anteriormente mencionados. Hay muchos esfuerzos dedicados al análisis de sus propiedades y a evaluar su impacto en la evolución de la galaxia anfitriona en escalas de pc a kpc. Sin embargo, en el caso de los AGNs los estudios se han centrado en los sistemas más luminosos, donde se espera que los ‘outflows’ sean más poderosos y, por tanto, más fácil de detectar y caracterizar. Aún no está claro si los ‘outflows’ son también comunes, o incluso su presencia ubicua, en LINERs, ya que su presencia en esta población de AGNs ha sido en gran medida no explorada. En esta tesis abordamos este tema utilizando tres metodologías distintas que se van describiendo en los capítulos. Espectroscopía óptica de LINERs de tipo 2: Presentamos en primer lugar el análisis de datos de espectroscopía de rendija larga de nueve LINERs de tipo 2, obtenidos con el Tele, scopio Espacial Hubble (HST) y de la muestra del Palomar. Este trabajo complementa al estudio anterior de Cazzoli et al. (2018) con LINERs de tipo 1. Los objetivos principales son dos: (i) detectar en las líneas de emisión de Balmer una componente ancha originada en la región de líneas anchas, y (ii) buscar indicadores de ‘outflows’ en las líneas de emisión como una componente ancha (σ‘ 500 km s−1) desplazada hacia el azul. Detectamos una componente ancha en las líneas de Balmer en el 67% de los espectros del HST y en el 25% de los espectros del Palomar. En cuanto a los ‘outflows’, encontramos que el 35% de los LINER de tipo 2 son buenos candidatos para albergarlos. Una búsqueda de ‘outflows’ en gas ionizado en un atlas de imágenes de Hα de LINERs cercanos. A continuación, buscamos sistemáticamente ‘outflows’ en una muestra de 70 LINERs cercanos, analizando la distribución del gas ionizado en estos sistemas con imágenes de ALFOSC/NOT e imágenes de archivo del HST de banda estrecha. Pudimos identificar las principales morfologías del gas Hα y detectar posibles ‘outflows’ en forma de gas extendido en el 32% de los objetos. Después, combinando las imágenes con datos cinemáticos de la literatura, descubrimos que el 50% de los LINER locales tienen ‘outflows’ que se detectan en distintas fases del gas. Estos resultados indican que los ‘outflows’ son comunes en AGNs de baja luminosidad, como los LINERs. Análisis de LINERs candidatos a tener ‘outflows’ con datos de espectroscopía de campo integral (IFS) con MEGARA/GTC. Por último, utilizamos los datos de IFS para confirmar o no los candidatos a ‘outflows’ identificados en los dos trabajos anteriores, pero esta vez resolviendo la emisión espacialmente. Para ello utilizamos los datos de MEGARA/GTC de nueve LINERs en tres bandas espectrales distintas en el rango óptico. Estudiamos como primer caso el prototípico LINER NGC1052 (complementando con datos propios de MUSE/VLT). Detectamos en este objeto un ‘outflow’ en gas ionizado, probablemente impulsado por un ‘jet’, que se propaga en una región de gas turbulento provocando burbujas a escalas de kpc. A continuación analizamos los otros ocho objetos de la muestra. Encontramos indicaciones cinemáticas de la presencia de ‘outflows’ de gas ionizado en cuatro de estos LINERs (es decir, el 50%). El LINER NGC 4438 es el único objeto de nuestra muestra para el que detectamos, con datos de MEGARA, tres componentes cinemáticas espacialmente resueltas en todas las líneas de emisión. Estas se relacionan con el disco de gas de la galaxia y con un ‘outflow’ con forma de burbuja, que ya había sido detectado anteriormente con imágenes de alta resolución espacial., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Gaseous flows inside and outside galaxies are key to understanding galaxy evolution, as they regulate their star formation activity and chemical enrichment across cosmic time. We study the interstellar medium (ISM) kinematics of a sample of 330 galaxies with C III] or He II emission using far-ultraviolet (far-UV) ISM absorption lines detected in the ultra deep spectra of the VANDELS survey. These galaxies span a broad range of stellar masses from 10(8) to 10(11) M-circle dot, and star formation rates (SFRs) from 1 to 500 M-circle dot yr(-1) in the redshift range between 2 and 5. We find that the bulk ISM velocity along the line of sight (v(IS)) is globally in outflow, with a v(IS) of -60 +/- 10 km s(-1) for low-ionisation gas traced by Si II lambda 1260 angstrom, C II lambda 1334 angstrom, Si II lambda 1526 angstrom, and Al II lambda 1670 angstrom absorption lines, and a v(IS) of -160 +/- 30 and -170 +/- 30 km s(-1) for higher ionisation gas traced respectively by Al III lambda lambda 1854-1862 angstrom and Si IV lambda lambda 1393-1402 angstrom. Interestingly, we notice that BPASS models are able to better reproduce the stellar continuum around the Si IV doublet than other stellar population templates. For individual galaxies, 34% of the sample has a positive ISM velocity shift, almost double the fraction reported at lower redshifts. We additionally derive a maximum outflow velocity v(max) for the average population, which is of the order of similar to -500 and similar to -600 km s(-1) for the lower and higher ionisation lines, respectively. Comparing v(IS) to the host galaxies properties, we find no significant correlations with stellar mass M-star or SFR, and only a marginally significant dependence (at similar to 2 sigma) on morphology-related parameters, with slightly higher velocities found in galaxies of smaller size (probed by the equivalent radius r(T)(50)) higher concentration (C-T), and higher SFR surface density Sigma(SFR). From the spectral stacks, v(max) shows a similarly weak dependence on physical properties (at similar or equal to 2 sigma). Moreover, we do not find evidence of enhanced outflow velocities in visually identified mergers compared to isolated galaxies. From a physical point of view, the outflow properties are consistent with accelerating momentum-driven winds, with densities decreasing towards the outskirts. Our moderately lower ISM velocities compared to those found in similar studies at lower redshifts suggest that inflows and internal turbulence might play an increased role at z > 2 and weaken the outflow signatures. Finally, we estimate mass-outflow rates (M) over dot(out) that are comparable to the SFRs of the galaxies (hence a mass-loading factor eta of the order of unity), and an average escape velocity of 625 km s(-1), suggesting that most of the ISM will remain bound to the galaxy halo.

Three radio sources (10913, 44, and 4092) are found in the COSMOS field within a massive galaxy group detected in X-ray at z ≈ 0:35. Two of them, radio galaxies 10913 and 44, have extended and interestingly shaped radio morphologies, i.e. bent jets. We analyze the radio sources and their 10’ x 10’ environment in the optical regime. Modeling the light distributions of their optical counterparts with the Sersic profile we obtain Sersic index values: 3.946 ± 0.005, 4.77 ± 0.01, and 4.37 ± 0.02 for 10913, 44, and 4092 respectively. The results of modeling suggest that the optical counterparts of radio galaxies 10913 and 44 are elliptical galaxies, possibly with a core. The light distribution in the central part of the optical counterpart of radio source 4092 follows the Sersic profile well. However, residual light in its outer parts remains and needs to be investigated further. By analyzing the spatial distribution of optical sources in the 10’ x 10’ environment of radio sources and extracting the ones in highly dense areas, we detect a large concentration of densely distributed galaxies, that spatially corresponds to the group detected in X-ray, and that has substructures. The color index of the member galaxies does not seem to affect their position within the large concentration. We find a long (≈ 6 mag), nearly horizontal, and ≈ 1 mag wide structure - likely a red sequence in the corresponding galaxy color-magnitude diagrams. Using spectroscopic instead of photometric redshift in future work, would give more precise results and possibly better-defined (narrower) sequence. The obtained results agree with the idea of the potential galaxy group being a non-relaxed system, possibly caught in the process of its creation through the merging of more than one smaller group (likely around each radio source). Additional and in some aspects, more advanced research is needed in optical as well as at other wavelengths (radio, X-rays) to further investigate this scenario. Tri radioizvora (10913, 44 i 4092) pronađeni su u polju COSMOS, unutar grupe galaksija na z ≈ 0:35, prethodno detektirane u rendgenskom valnom području. Radiogalaksije 10913 i 44 imaju izduženu i zanimljivo oblikovanu radiomorfologiju (savijene mlaznice). Mi analiziramo galaksije i njihovo 10' x 10' okruženje u optičkom valnom području. Modelirajući raspodjelu svjetla njihovih optičkih ekvivalenata Sersicovim profilom dobivamo vrijednosti Sersicovog indeksa: 3.946 ± 0.005, 4.77 ± 0.01 i 4.37 ± 0.02 za redom 10913, 44 i 4092. Prema rezultatima modeliranja, čini se kako su optički ekvivalenti radiogalaksija 10913 i 44 eliptične galaksije, moguće s jezgrom. Raspodjela svjetla u središnjem dijelu optičkog ekvivalenta radioizvora 4092 dobro slijedi Sersicov profil, međutim u vanjskim dijelovima galaksije ostaje rezidualno svjetlo, koje se treba dalje istražiti. Analizom prostorne raspodjele optičkih izvora u 10' x 10' okolini radioizvora te izdvajanjem samo onih iz područja povećane gustoće, detektiramo veću nakupinu gusto raspoređenih galaksija koja se prostorno poklapa s prethodno detektiranom grupom u rendgenskom području te se sastoji od podstruktura. Nije uočena povezanost između indeksa boje galaksija članova i njihovog položaja unutar velike nakupine. Nađena je dugačka (≈ 6 mag), gotovo vodoravna struktura širine ≈ 1 mag u dijagramima magnituda - boja za galaksije, vjerojatno crveni niz. Precizniji rezultat te moguće bolje definiran (uži) crveni niz traže dodatnu analizu, uz uporabu preciznijih sprektroskopskih crvenih pomaka. Dobiveni rezultati su u skladu s idejom da je potencijalna grupa neopušten sustav, moguće opažen u procesu nastanka kroz spajanje više manjih grupa (vjerojatno po jedna oko svakog od radioizvora). Dodatno i u nekim aspektima naprednije istraživanje je potrebno, kako u optičkom području tako i na drugim valnim duljinama (radiovalno i rendgensko područje), kako bi se ova mogućnost dalje istražila.

Here, we demonstrate that polarization properties show a wide diversity depending on viewing angles. To simulate images of a supermassive black hole and surrounding plasma, we performed a full-polarimetric general relativistic radiative transfer based on three-dimensional general relativistic magnetohydrodynamics models with moderate magnetic strengths. Under an assumption of a hot-jet and cold-disk in the electron temperature prescription, we confirmed a typical scenario where polarized synchrotron emissions from the funnel jet experience Faraday rotation and conversion in the equatorial disk. Further, we found that linear polarization vectors are inevitably depolarized for edge-on-like observers, whereas a portion of vectors survive and reach the observers in face-on-like cases. We also found that circular polarization components have persistent signs in the face-on cases, and changing signs in the edge-on cases. It is confirmed that these features are smoothly connected via intermediate viewing-angle cases. These results are due to Faraday rotation/conversion for different viewing angles, and suggest that a combination of linear and circular polarimetry can give a constraint on the inclination between the observer and black hole's (and/or disk's) rotating-axis and plasma properties in the jet--disk structure. These can also lead to a more statistical and unified interpretation for a diversity of emissions from active galactic nuclei., 11 pages, 6 figures. Contribution to the Galaxies Special Issue "Challenges in Understanding Black Hole Powered Jets with VLBI". Movie available at https://youtu.be/065qAx6Tff0

We study the demographics of z similar to 6 broad-line quasars in the black hole (BH) mass-luminosity plane using a sample of more than 100 quasars at 5.7 < z < 6.5. These quasars have well-quantified selection functions and nearly one-third of them also have virial BH masses estimated from near-IR spectroscopy. We use forward modelling of parametrized intrinsic distributions of BH masses and Eddington ratios, and account for the sample flux limits and measurement uncertainties of the BH masses and luminosities. We find significant differences between the intrinsic and observed distributions of the quantities due to measurement uncertainties and sample flux limits. There is also marginal evidence that the virial BH masses are susceptible to a positive luminosity-dependent bias (BH mass is overestimated when luminosity is above the average), and that the mean Eddington ratio increases with BH mass. Our models provide reliable constraints on the z similar to 6 BH mass function at M-BH > 10(8.5) M-circle dot, with a median 1 sigma uncertainty of similar to 0.5 dex in abundance. The intrinsic Eddington ratio distribution of M-BH > 10(8.5) M-circle dot quasars can be approximated by a mass-dependent Schechter model, with a broad peak around log (L-bol/L-Edd)similar to -0.9. We also find that, at 4.5 less than or similar to z less than or similar to 6, the number densities of more massive BHs tend to decline more rapidly with increasing redshift, contrary to the trend at 2.5 less than or similar to z less than or similar to 4.5 reported previously.

Active galactic nuclei (AGN) forming in the early universe are thought to be the primary source of hard ionizing photons contributing to the reionization of intergalactic helium. However, the number density and spectral properties of high-redshift AGN remain largely unconstrained. In this work, we make use of physically-informed models calibrated with a wide variety of available observations to provide estimates for the role of AGN throughout the Epoch of Reionization. We present AGN luminosity functions in various bands between z = 2 to 7 predicted by the well-established Santa Cruz semi-analytic model, which includes modelling of black hole accretion and AGN feedback. We then combine the predicted AGN populations with a physical spectral model for self-consistent estimates of ionizing photon production rates, which depend on the mass and accretion rate of the accreting supermassive black hole. We then couple the predicted comoving ionizing emissivity with an analytic model to compute the subsequent reionization history of intergalactic helium and hydrogen. This work demonstrates the potential of coupling physically motivated analytic or semi-analytic techniques to capture multi-scale physical processes across a vast range of scales (here, from AGN accretion disks to cosmological scales). Our physical model predicts an intrinsic ionizing photon budget well above many of the estimates in the literature, meaning that helium reionization can comfortably be accomplished even with a relatively low escape fraction. We also make predictions for the AGN populations that are expected to be detected in future \emph{James Webb Space Telescope} surveys., Comment: 28 pages, 23 figures, accepted for publication in MNRAS

The co-evolution between central supermassive black holes (BH), their host galaxies, and dark matter halos is still a matter of intense debate. Present theoretical models suffer from large uncertainties and degeneracies, for example, between the fraction of accreting sources and their characteristic accretion rate. In recent work we showed that Active Galactic Nuclei (AGN) clustering represents a powerful tool to break degeneracies when analysed in terms of mean BH mass, and that AGN bias at fixed stellar mass is largely independent of most of the input parameters, such as the AGN duty cycle and the mean scaling between BH mass and host galaxy stellar mass. In this paper we take advantage of our improved semi-empirical methodology and recent clustering data derived from large AGN samples at $z \sim 1.2$, demonstrate that the AGN bias as a function of host galaxy stellar mass is a crucial diagnostic of the BH--galaxy connection, and is highly dependent on the scatter around the BH mass--galaxy mass scaling relation and on the relative fraction of satellite and central active BHs. Current data at $z \sim 1.2$ favour relatively high values of AGN in satellites, pointing to a major role of disc instabilities in triggering AGN, unless a high minimum host halo mass is assumed. The data are not decisive on the magnitude/covariance of the BH-galaxy scatter at $z \sim 1.2$ and intermediate host masses $M_\mathrm{star} \lesssim 10^{11} \,\mathrm{M}_\odot$. However, future surveys like Euclid/LSST will be pivotal in shedding light on the BH--galaxy co-evolution., 14 pages, 10 figures, accepted for publication in MNRAS

Accretion states, which are universally observed in stellar-mass black holes in X-ray binaries, are also anticipated in active galactic nuclei (AGN). This is the case at low luminosities, when the jet-corona coupling dominates the energy output in both populations. Previous attempts to extend this framework to a wider AGN population have been extremely challenging due to heavy hydrogen absorption of the accretion disc continuum and starlight contamination from the host galaxies. We present the luminosity-excitation diagram (LED), based on the [OIV]25.9µm and [NeII]12.8µm mid-infrared nebular line fluxes. This tool enables to probe the accretion disc contribution to the ionising continuum. When applied to a sample of 167 nearby AGN, the LED recovers the characteristic q-shaped morphology outlined by individual X-ray binaries during a typical accretion episode, allowing us to tentatively identify the main accretion states. The soft state would include broad-line Seyferts and about half of the Seyfert 2 population, showing highly excited gas and radio-quiet cores consistent with disc-dominated nuclei. The hard state mostly includes low-luminosity AGN (-3 Ledd) characterised by low-excitation radio-loud nuclei and a negligible disc contribution. The remaining half of Seyfert 2 nuclei and the bright LINERs show low excitation at high accretion luminosities, and could be identified with the bright-hard and intermediate states. Their hosts show ongoing star formation in the central kiloparsecs. We discuss the above scenario, its potential links with the galaxy evolution picture and the possible presence of accretion state transitions in AGN, as suggested by the growing population of changing-look quasars. &nbsp

We study the relation between obscuration and supermassive black hole (SMBH) accretion using a large sample of hard X-ray selected active galactic nuclei (AGNs). We find a strong decrease in the fraction of obscured sources above the Eddington limit for dusty gas (log lambda(Edd) >= -2) confirming earlier results, and consistent with the radiation-regulated unification model. This also explains the difference in the Eddington ratio distribution functions (ERDFs) of type 1 and type 2 AGNs obtained by a recent study. The break in the ERDF of nearby AGNs is at log lambda*(Edd) = -1.34 +/- 0.07. This corresponds to the lambda(Edd) where AGNs transition from having most of their sky covered by obscuring material to being mostly devoid of absorbing material. A similar trend is observed for the luminosity function, which implies that most of the SMBH growth in the local universe happens when the AGN is covered by a large reservoir of gas and dust. These results could be explained with a radiation-regulated growth model, in which AGNs move in the N-H-lambda(Edd) plane during their life cycle. The growth episode starts with the AGN mostly unobscured and accreting at low lambda(Edd). As the SMBH is further fueled, lambda(Edd), N-H and the covering factor increase, leading the AGN to be preferentially observed as obscured. Once lambda(Edd) reaches the Eddington limit for dusty gas, the covering factor and N-H rapidly decrease, leading the AGN to be typically observed as unobscured. As the remaining fuel is depleted, the SMBH goes back into a quiescent phase., The Astrophysical Journal, 938 (1), ISSN:0004-637X, ISSN:2041-8213

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES The supermassive black holes at the centre of massive galaxies can influence their host evolution. During their active phase, the matter in the central parsecs of galaxies flows onto the blackhole creating an accretion disk and ultimately feeding the SMBH. The heated accretion disk releases energy to the surrounding medium in the form of radiation pressure, the so-called Quasar winds, or by relativistic jets of particles. Both these phenomena can push the gas clouds out of the central galaxy region up to kiloparsec scales. The gas outflows observed in different phases can influence the host galaxy. In this thesis, we analyse the gas kinematics in two samples of active galaxies. The first is the Seyfert sample composed of 6 nearby Seyfert galaxies observed with Gemini Near-infrared Integral Field Spectrograph in the J and K bands. We study the kinematics of the ionised gas, traced by Paβ and [FeII] emission lines, and molecular gas, traced by the H22.12µm, in these galaxies. By decomposing the emission-line profiles in distinct kinematic components, we identify ionised gas outflows in four galaxies and molecular outflows traced by distinct kinematic components in two. The mass outflow rates are in the range e 0.005−12.49Myr−1 and the kinetic powers of 1039−1042 ergs−1. We observe signatures of H2 streaming motions towards the centre in three galaxies, but they are not enough to feed the AGN at the current accretion rate. The second is the QSO sample composed of 18 type 2 quasars at z < 0.2 selected from the Quasar Feedback Survey galaxies, observed by the Very Large Telescope Multi-Unit Spectroscopic Explorer. We use the [OIII]5007 as a tracer of the ionised gas outflows. In this sample, we adopt a different analysis approach to identify and characterise the outflows. Multiple Gaussian curves are fitted to the [OIII] emission-line to reproduce the emission-line profile. From the modelled spectra, we derive theW80, the width of the line that contains 80 per cent of the emitted flux, and use this quantity as a proxy to identify the spaxels dominated by outflows as the ones with W80 > 600kms−1. From the 15 galaxies with detected [OIII]5007 emission lines, we identify ionised gas outflows in 13. The masses of ionised outflows are 104 −106M, corresponding to 10-100 per cent of the total mass of ionised gas. The mass outflow rates are in the rages 10−2−100 Myr−1 and the kinetic powers 1038 −1042 ergs−1. By comparing both samples with the literature, we see an increased scatter in the wind scaling relation. The kinetic coupling efficiencies are smaller than the values predicted for the coupling efficiencies in theoretical models. However, this does not imply that the outflows cannot suppress the star-formation in the host galaxy. Buracos negros supermassivos que residem no centro de galáxias massivas podem influenciar a evolução de suas galáxias hospedeiras. Durante sua fase ativa, a matéria presente no kiloparsec central das galáxias flui em direção ao buraco negro supermassivo criando um disco de acreção até alimentar o buraco negro supermassivo. O gás aquecido presente no disco de acreção libera energia para para o meio que o rodeia na forma de pressão de radiação, fenômeno chamado de ventos de Quasares, ou de jatos de partículas relativísticas. Ambos fenômenos podem empurrar nuvens de gás da região central das galáxias até distâncias de kiloparsecs. Outflows de gás, observado em diferentes fases do gás, podem influenciar a galáxia hospedeira. Nesta tese, analisamos a cinemática do gás em duas amostras de galáxias ativas. A primeira é a amostra de galáxias Seyfert composta por 6 galáxias Seyfert próximas observadas com o Near-infrared Integral Fields Spectrograph nas bandas J e K. Estudamos a cinemática do gás ionizado, traçado pelas linhas de emissão do Paβ e [FeII], e do gás molecular, traçado pela linha H22.12µm, nestas galáxias. Ao decompor os perfis das linhas de emissão em componentes cinemáticas distintas, identificamos outflows de gás ionizado em quatro galáxias e outflows de gás molecular emduas. As taxas de outflow estão entre 0.005 e 12.49Myr−1 que correspondem à potências cinéticas de 1039 −1042 ergs−1. Observamos assinaturas de movimentos da molécula do H2 emdireção ao centro em três galáxias, mas com massa insuficiente para para alimentar o núcleo ativo mantendo a taxa de acreção atual. A segunda é a amostra de QSOs composta por 18 quasares do tipo 2 com z < 0.2 selecionados a partir do Quasar Feedback Survey observados com oMulti-Unit Spectroscopic Explorer no Very Large Telescope. Usamos a linha de emissão [OIII]5007 como um traçador dos outflows de gás ionizado. Múltiplas componentes Gaussianas são ajustas à linha de emissão do [OIII] para reproduzir o perfil da linha de emissão. A partir do espectro modelado, derivamos a quantidade W80, a largura da linha que corresponde à 80% do fluxo emitido. UsamosW80 >600kms−1 como um limite para identificar os pixeis dominados por outflows. Das 15 galáxias que possuem a linha do [OIII]5007 detectada, identificamos outflows de gás ionizado em 13. As massas de outflows ionizados estão entre 104 e 106M, correspondendo de 10 à 100% da mass total de gás ionizado. As taxas de outflow estão entre 10−2 e 100Myr−1 e potências cinéticas entre 1038 e 1042 ergs−1. Ao comparar as duas amostras com a literatura, notamos um aumento no espalhamento na relação de escala dos outf lows. As eficiências de acoplamento cinéticas são menores do que os valores para a eficiência de acoplamento determinados em modelos teóricos. No entando, este resultado não implica que os outflows observados não podem suprimir a formação estelar na galáxia hospedeira.

A well-known active galaxy of the blazar type, S5 0716+714, is characterized by a particularly high variability duty cycle on short-time scales at optical frequencies. As such, the source was subjected to numerous monitoring programs, including both ground-based as well as space-borne telescopes. On closer inspection of the most recent accumulation of the data provided by the Transiting Exoplanet Survey Satellite, we have noticed several conspicuous events with `volcano-like' symmetric shape, lasting all for several hours, which closely resemble the achromatic events detected with the previous Whole Earth Blazar Telescope campaigns targeting the source. We propose that those peculiar features could be due to the gravitational micro-lensing of the innermost segments of the precessing jet in the system, by a binary lens. We study the magnification pattern of the lens with the inverse-ray shooting method, and the source trajectory parameters with the Python package MuLensModel. In this way, we were able to fit successfully all the selected events with a single lens, adjusting slightly only the source trajectory parameters for each lensing event. Based on the fit results, we postulate the presence of a massive binary lens, containing an intermediate-mass black hole, possibly even a super-massive one, and a much less massive companion (by a factor of $\lesssim 0.01$), located within the host galaxy of the blazar, most likely the central kiloparsec region. We discuss the major physical implications of the proposed scenario regarding the quest for the intermediate-mass and dual supermassive black holes in active galaxies., accepted for publication in the Astrophysical Journal

We present new CO(2–1) observations of a representative sample of 24 local (z, EB and AL acknowledge the support from Comunidad de Madrid through the Atracción de Talento grant 2017-T1/TIC-5213. This research has been partially funded by the Spanish State Research Agency (AEI) Project MDM-2017-0737 Unidad de Excelencia ‘María de Maeztu’– Centro de Astrobiología (INTA-CSIC). MPS acknowledges support from the Comunidad de Madrid through the Atracción de Talento Investigador Grant 2018-T1/TIC-11035 and PID2019-105423GA-I00 (MCIU/AEI FEDER, UE). AAH, MVM and SGB acknowledge support from grant PGC2018-094671-B-I00 (MCIU/AEI/FEDER,UE). SGB acknowledges support from the research project PID2019-106027GA-C44 of the Spanish Ministerio de Ciencia e Innovación. DR acknowledges support from STFC through grant ST/S000488/1. AL, LC and SA acknowledge the support from grant PID2019-106280GB-I00 (MCIU/AEI/FEDER,UE). SC acknowledges financial support from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). MSG acknowledges support from the Spanish Ministerio de Economía y Competitividad through the grants BES-2016-078922 and ESP2017-83197-P. AP gratefully acknowledges financial support from STFC through grant ST/T000244/1. FV acknowledges support from the Carlsberg Foundation Research Grant CF18-0388 ‘Galaxies: Rise and Death’. The Cosmic Dawn Center (DAWN) is funded by the Danish National Research Foundation under grant No. 140. AU acknowledges support from the Spanish grants PGC2018-094671-B-I00, funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”, and PID2019-108765GB-I00, funded by MCIN/AEI/10.13039/501100011033. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2013.1.00243.S, ADS/JAO.ALMA#2013.1.00271.S, ADS/JAO.ALMA#2015.1.00714.S, ADS/JAO.ALMA#2017.1.00255.S, ADS/JAO.ALMA#2017.1.00395.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ.

Full list of authors: Issaoun, Sara; Wielgus, Maciek; Jorstad, Svetlana; Krichbaum, Thomas P.; Blackburn, Lindy; Janssen, Michael; Chan, Chi-kwan; Pesce, Dominic W.; Gomez, Jose L.; Akiyama, Kazunori; Moscibrodzka, Monika; Marti-Vidal, Ivan; Chael, Andrew; Lico, Rocco; Liu, Jun; Ramakrishnan, Venkatessh; Lisakov, Mikhail; Fuentes, Antonio; Zhao, Guang-Yao; Moriyama, Kotaro; Broderick, Avery E.; Tiede, Paul; MacDonald, Nicholas R.; Mizuno, Yosuke; Traianou, Efthalia; Loinard, Laurent; Davelaar, Jordy; Gurwell, Mark; Lu, Ru-Sen; Alberdi, Antxon; Alef, Walter; Algaba, Juan Carlos; Anantua, Richard; Asada, Keiichi; Azulay, Rebecca; Bach, Uwe; Baczko, Anne-Kathrin; Ball, David; Balokovic, Mislac; Barrett, John; Baubock, Michi; Benson, Bradford A.; Bintley, Dan; Blundell, Raymond; Boland, Wilfred; Bouman, Katherine L.; Bower, Geoffrey C.; Boyce, Hope; Bremer, Michael; Brinkerink, Christiaan D.; Brissenden, Roger; Britzen, Silke; Broguiere, Dominique; Bronzwaer, Thomas; Bustamante, Sandra; Byun, Do-Young; Carlstrom, John E.; Ceccobello, Chiara; Chatterjee, Koushik; Chatterjee, Shami; Chen, Ming-Tang; Chen, Yongjun; Cho, Ilje; Christian, Pierre; Conroy, Nicholas S.; Conway, John E.; Cordes, James M.; Crawford, Thomas M.; Crew, Geoffrey B.; Cruz-Osorio, Alejandro; Cui, Yuzhu; De Laurentis, Mariafelicia; Deane, Roger; Dempsey, Jessica; Desvignes, Gregory; Dexter, Jason; Doeleman, Sheperd S.; Dhruv, Vedant; Quijano, Sergio Abraham Dzib; Eatough, Ralph P.; Emami, Razieh; Falcke, Heino; Farah, Joseph; Fish, Vincent L.; Fomalont, Ed; Ford, H. Alyson; Fraga-Encinas, Raquel; Freeman, William T.; Friberg, Per; Fromm, Christian M.; Galison, Peter; Gammie, Charles F.; Garcia, Roberto; Gentaz, Olivier; Georgiev, Boris; Goddi, Ciriaco; Gold, Roman; Gomez-Ruiz, Arturo, I; Gu, Minfeng; Hada, Kazuhiro; Haggard, Daryl; Hecht, Michael H.; Hesper, Ronald; Ho, Luis C.; Ho, Paul; Honma, Mareki; Huang, Chih-Wei L.; Huang, Lei; Hughes, David H.; Ikeda, Shiro; Impellizzeri, C. M. Violette; Inoue, Makoto; James, David J.; Jannuzi, Buell T.; Jeter, Britton; Jiang, Wu; Jimenez-Rosales, Alejandra; Johnson, Michael D.; Joshi, Abhishek, V; Jung, Taehyun; Karami, Mansour; Karuppusamy, Ramesh; Kawashima, Tomohisa; Keating, Garrett K.; Kettenis, Mark; Kim, Dong-Jin; Kim, Jae-Young; Kim, Jongsoo; Kim, Junhan; Kino, Motoki; Koay, Jun Yi; Kocherlakota, Prashant; Kofuji, Yutaro; Koch, Patrick M.; Koyama, Shoko; Kramer, Carsten; Kramer, Michael; Kuo, Cheng-Yu; La Bella, Noemi; Lauer, Tod R.; Lee, Daeyoung; Lee, Sang-Sung; Leung, Po Kin; Levis, Aviad; Li, Zhiyuan; Lindahl, Greg; Lindqvist, Michael; Liu, Kuo; Liuzzo, Elisabetta; Lo, Wen-Ping; Lobanov, Andrei P.; Lonsdale, Colin; Mao, Jirong; Marchili, Nicola; Markoff, Sera; Marrone, Daniel P.; Marscher, Alan P.; Matsushita, Satoki; Matthews, Lynn D.; Medeiros, Lia; Menten, Karl M.; Michalik, Daniel; Mizuno, Izumi; Mizuno, Yosuke; Moran, James M.; Mueller, Cornelia; Mus, Alejandro; Musoke, Gibwa; Myserlis, Ioannis; Nadolski, Andrew; Nagai, Hiroshi; Nagar, Neil M.; Nakamura, Masanori; Narayan, Ramesh; Narayanan, Gopal; Natarajan, Iniyan; Nathanail, Antonios; Neilsen, Joey; Neri, Roberto; Ni, Chunchong; Noutsos, Aristeidis; Nowak, Michael A.; Oh, Junghwan; Okino, Hiroki; Olivares, Hector; Ortiz-Leon, Gisela N.; Oyama, Tomoaki; Ozel, Feryal; Palumbo, Daniel C. M.; Paraschos, Georgios Filippos; Park, Jongho; Parsons, Harriet; Patel, Nimesh; Pen, Ue-Li; Pietu, Vincent; Plambeck, Richard; PopStefanija, Aleksandar; Porth, Oliver; Potzl, Felix M.; Prather, Ben; Preciado-Lopez, Jorge A.; Psaltis, Dimitrios; Pu, Hung-Yi; Rao, Ramprasad; Rawlings, Mark G.; Raymond, Alexander W.; Rezzolla, Luciano; Ricarte, Angelo; Ripperda, Bart; Roelofs, Freek; Rogers, Alan; Ros, Eduardo; Romero-Canizales, Cristina; Roshanineshat, Arash; Rottmann, Helge; Roy, Alan L.; Ruiz, Ignacio; Ruszczyk, Chet; Rygl, Kazi L. J.; Sanchez, Salvador; Sanchez-Arguelles, David; Sanchez-Portal, Miguel; Sasada, Mahito; Satapathy, Kaushik; Savolainen, Tuomas; Schloerb, F. Peter; Schuster, Karl-Friedrich; Shao, Lijing; Shen, Zhiqiang; Small, Des; Sohn, Bong Won; SooHoo, Jason; Souccar, Kamal; Sun, He; Tazaki, Fumie; Tetarenko, Alexandra J.; Tilanus, Remo P. J.; Titus, Michael; Torne, Pablo; Trent, Tyler; Trippe, Sascha; van Bemmel, Ilse; van Langevelde, Huib Jan; van Rossum, Daniel R.; Vos, Jesse; Wagner, Jan; Ward-Thompson, Derek; Wardle, John; Weintroub, Jonathan; Wex, Norbert; Wharton, Robert; Wiik, Kaj; Witzel, Gunther; Wondrak, Michael; Wong, George N.; Wu, Qingwen; Yamaguchi, Paul; Yoon, Doosoo; Young, Andre; Young, Ken; Younsi, Ziri; Yuan, Feng; Yuan, Ye-Fei; Zensus, J. Anton; Zhang, Shuo; Zhao, Shan-Shan.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., The blazar J1924–2914 is a primary Event Horizon Telescope (EHT) calibrator for the Galactic center's black hole Sagittarius A*. Here we present the first total and linearly polarized intensity images of this source obtained with the unprecedented 20 μas resolution of the EHT. J1924–2914 is a very compact flat-spectrum radio source with strong optical variability and polarization. In April 2017 the source was observed quasi-simultaneously with the EHT (April 5–11), the Global Millimeter VLBI Array (April 3), and the Very Long Baseline Array (April 28), giving a novel view of the source at four observing frequencies, 230, 86, 8.7, and 2.3 GHz. These observations probe jet properties from the subparsec to 100 pc scales. We combine the multifrequency images of J1924–2914 to study the source morphology. We find that the jet exhibits a characteristic bending, with a gradual clockwise rotation of the jet projected position angle of about 90° between 2.3 and 230 GHz. Linearly polarized intensity images of J1924–2914 with the extremely fine resolution of the EHT provide evidence for ordered toroidal magnetic fields in the blazar compact core. © 2022. The Author(s). Published by the American Astronomical Society., The Event Horizon Telescope Collaboration thanks the following organizations and programs: the Academy of Finland (projects 274477, 284495, 312496, 315721); the Agencia Nacional de Investigación y Desarrollo (ANID), Chile via NCN19_058 (TITANs) and Fondecyt 3190878, the Alexander von Humboldt Stiftung; an Alfred P. Sloan Research Fellowship; Allegro, the European ALMA Regional Centre node in the Netherlands, the NL astronomy research network NOVA and the astronomy institutes of the University of Amsterdam, Leiden University and Radboud University; the black hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Consejo Nacional de Ciencia y Tecnología (CONACYT, Mexico, projects U0004-246083, U0004-259839, F0003-272050, M0037-279006, F0003-281692, 104497, 275201, 263356); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Dirección General de Asuntos del Personal Académico-Universidad Nacional Autónoma de México (DGAPA-UNAM, projects IN112417 and IN112820); the European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); MICINN Research Project PID2019-108995GB-C22; the Gordon and Betty Moore Foundation (grant GBMF-3561); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; Joint Princeton/Flatiron and Joint Columbia/Flatiron Postdoctoral Fellowships, research at the Flatiron Institute is supported by the Simons Foundation; the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJSSW- SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007); the Malaysian Fundamental Research Grant Scheme (FRGS) FRGS/1/2019/STG02/UM/02/6; the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119- M-001-027, 107-2119-M-001-017, 107-2119-M-001-020, 107-2119-M-110-005, 108-2112-M-001-048, and 109-2124-M-001-005); the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC20K1567, NASA Astrophysics Theory Program grant 80NSSC20K0527, NASA NuSTAR award 80NSSC20K0645); the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1555365,AST-1615796, AST-1715061, AST-1716327, AST-1903847,AST-2034306); the Natural Science Foundation of China (grants 11573051, 11633006, 11650110427, 10625314, 11721303, 11725312, 11933007, 11991052, 11991053); a fellowship of China Postdoctoral Science Foundation (2020M671266); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, 2015- R1D1A1A01056807, the Korea Research Fellowship Program: NRF-2015H1D3A1066561, Basic Research Support Grant 2019R1F1A1059721); the Netherlands Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and Spinoza Prize SPI 78-409; the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648) the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Spanish Ministerio de Economía y Competitividad (grants PGC2018-098915-B-C21, AYA2016-80889-P, PID2019-108995GB-C21); the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709); the Toray Science Foundation; the Consejería de Economía, Conocimiento, Empresas y Universidad of the Junta de Andalucía (grant P18-FR-1769), the Consejo Superior de Investigaciones Científicas (grant 2019AEP112); the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001); the European Union's Horizon 2020 research and innovation program under grant agreement No 730562 RadioNet; ALMA North America Development Fund; the Academia Sinica; Chandra DD7-18089X and TM6-17006X; the GenT Program (Generalitat Valenciana) Project CIDEGENT/2018/021. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI-1743442. XSEDE Stampede2 resource at TACC was allocated through TG-AST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www.calculquebec.ca) and Compute Canada (http://www.computecanada.ca).

A decade ago the archetypal Seyfert-1 galaxy NGC 5548 was discovered to have undergone major spectral changes. The soft X-ray flux had dropped by a factor of 30 while new broad and blueshifted UV absorption lines appeared. This was explained by the emergence of a new obscuring wind from the accretion disk. Here we report on the striking long-term variability of the obscuring disk wind in NGC 5548 including new observations taken in 2021-2022 with the Swift Observatory and the Hubble Space Telescope's (HST) Cosmic Origins Spectrograph (COS). The X-ray spectral hardening as a result of obscuration has declined over the years, reaching its lowest in 2022 at which point we find the broad C IV UV absorption line to be nearly vanished. The associated narrow low-ionization UV absorption lines, produced previously when shielded from the X-rays, are also remarkably diminished in 2022. We find a highly significant correlation between the variabilities of the X-ray hardening and the equivalent width of the broad C IV absorption line, demonstrating that X-ray obscuration is inherently linked to disk winds. We derive for the first time a relation between the X-ray and UV covering fractions of the obscuring wind using its long-term evolution. The diminished X-ray obscuration and UV absorption are likely caused by an increasingly intermittent supply of outflowing streams from the accretion disk. This results in growing gaps and interstices in the clumpy disk wind, thereby reducing its covering fractions., Accepted for publication in The Astrophysical Journal Letters (ApJL), 6 pages, 4 figures

We estimated the spin values of the supermassive black holes (SMBHs) of the active galactic nuclei (AGN) for a large set of Narrow Line Seyfert 1 (NLS1) galaxies assuming the inclination angle between the line of sight and the axis of the accretion disk to be approximately 45 degrees. We found that for these objects the spin values are on average less than for the Seyfert 1 galaxies that we studied previously. In addition, we found that the dependencies of the spin on the bolometric luminosity and the SMBH mass are two to three times stronger that for Seyfert 1 galaxies, which could mean that at early stages of evolution NLS1 galaxies either have a low accretion rate or chaotic accretion, while at later stages they have standard disk accretion, which very effectively increases the spin value., 25 pages, 11 figures

Context. During the commissioning of the James Webb Space Telescope (JWST), the mid-infrared instrument (MIRI) observed NGC 6552 with the MIRI Imager and the Medium-Resolution Spectrograph (MRS). NGC 6552 is an active galactic nucleus (AGN) at a redshift of 0.0266 (DL = 120 Mpc) classified as a Seyfert 2 nucleus in the optical and Compton-thick AGN in the X-ray. Aims. This work exemplifies and demonstrates the MRS capabilities to study the mid-infrared (mid-IR) spectra and characterise the physical conditions and kinematics of the ionised and molecular gas in the nuclear regions of nearby galaxies. Methods. MIRI Imager observations covers the full NGC 6552 galaxy at 5.6 μm. MRS observations covers its nuclear region (3.6 × 4.3 kpc at 17.7-27.9 μm) in a wavelength range between 4.9 and 27.9 μm. These observations were obtained with the aim to investigate the persistence of the MIRI detectors (residual signal left from previous bright source observations). However, NGC 6552 observations demonstrate the performance and power of the MIRI instrument even with a non-optimal observational strategy. Results. We obtained the nuclear, circumnuclear, and central mid-IR spectra of NGC 6552. They provide the first clear observational evidence for a nuclear outflow in NGC 6552. The outflow contributes to 67±7% of the total line flux independent of the ionisation potential (27-187 eV) and critical densities (104-4 × 106 cm-3), showing an average blue-shifted peak velocity of -127±45 km s-1 and an outflow maximal velocity of 698±80 km s-1. Since the mid-IR photons penetrate dusty regions as efficiently as X-ray keV photons, we interpret these results as the evidence for a highly ionised, non-stratified, AGN-powered, and fast outflowing gas in a low density environment (few 103 cm-3) located very close (< 0.2 kpc) to the Compton-thick AGN. Nine pure rotational molecular Hydrogen lines are detected and spectrally resolved, and exhibit symmetric Gaussian profiles, consistent with the galactic rotation, and with no evidence of outflowing H2 material. We detect a warm H2 mass of 1.9 ± 1.1 × 107 M⊙ in the central region (1.8 kpc in diameter) of the galaxy, with almost 30% of that mass in the circumnuclear region. Line ratios confirm that NGC 6552 has a Seyfert nucleus with a black hole mass estimated in the range of 0.6-6 million solar masses. Conclusions. This work demonstrates the power of the newly commissioned MIRI Medium Resolution Spectrograph to reveal new insights in the kinematics and ionisation state of the interstellar medium around the dusty nuclear regions of nearby active galaxies., Astronomy & Astrophysics, 672, ISSN:0004-6361, ISSN:1432-0746

We present the results from a dense multi-wavelength (optical/UV, near-infrared (IR), and X-ray) follow-up campaign of the nuclear transient AT2017gge, covering a total of 1698 days from the transient's discovery. The bolometric lightcurve, the black body temperature and radius, the broad H and He I $\lambda$5876 emission lines and their evolution with time, are all consistent with a tidal disruption event (TDE) nature. A soft X-ray flare is detected with a delay of $\sim$200 days with respect to the optical/UV peak and it is rapidly followed by the emergence of a broad He II $\lambda$4686 and by a number of long-lasting high ionization coronal emission lines. This indicate a clear connection between a TDE flare and the appearance of extreme coronal line emission (ECLEs). An IR echo, resulting from dust re-radiation of the optical/UV TDE light is observed after the X-ray flare and the associated near-IR spectra show a transient broad feature in correspondence of the He I $\lambda$10830 and, for the first time in a TDE, a transient high-ionization coronal NIR line (the [Fe XIII] $\lambda$10798) is also detected. The data are well explained by a scenario in which a TDE occurs in a gas and dust rich environment and its optical/UV, soft X-ray, and IR emission have different origins and locations. The optical emission may be produced by stellar debris stream collisions prior to the accretion disk formation, which is instead responsible for the soft X-ray flare, emitted after the end of the circularization process., Comment: Accepted for publication in MNRAS

We present structural measurements of 145 spectroscopically selected intermediate-redshift (z similar to 0.7), massive (M-star similar to 10(11) M (circle dot)) post-starburst galaxies from the SQuIGG (L) over right arrowE i-band imaging. This deep imaging allows us to probe the sizes and structures of these galaxies, which we compare to a control sample of star-forming and quiescent galaxies drawn from the LEGA-C Survey. We find that post-starburst galaxies systematically lie similar to 0.1 dex below the quiescent mass-size (half-light radius) relation, with a scatter of similar to 0.2 dex. This finding is bolstered by nonparametric measures, such as the Gini coefficient and the concentration, which also reveal these galaxies to have more compact light profiles than both quiescent and star-forming populations at similar mass and redshift. The sizes of post-starburst galaxies show either negative or no correlation with the time since quenching, such that more recently quenched galaxies are larger or similarly sized. This empirical finding disfavors the formation of post-starburst galaxies via a purely central burst of star formation that simultaneously shrinks the galaxy and shuts off star formation. We show that the central densities of post-starburst and quiescent galaxies at this epoch are very similar, in contrast with their effective radii. The structural properties of z similar to 0.7 post-starburst galaxies match those of quiescent galaxies that formed in the early universe, suggesting that rapid quenching in the present epoch is driven by a similar mechanism to the one at high redshift.

We characterize the average X-ray and radio properties of quiescent galaxies (QGs) with $\log{(M_\star/M_\odot)}>10$ at $01.5$ is higher than that of star-forming galaxies (SFGs), derived in the same manner as QGs. The stacking analysis of the VLA-COSMOS images is conducted for the identical sample, and the radio signal for QGs is also detected up to $z\sim5$. We find that the radio AGN luminosity of QGs at $z>1.5$ is also higher than SFGs, which is in good agreement with the X-ray analysis. The enhanced AGN activity in QGs suggested by the individual analysis in the X-ray and radio wavelength supports its important role for quenching at high redshift. Their enhanced AGN activity is less obvious at $z, Comment: 24 pages, 20 figures, 2 tables, Accepted for publication in ApJ

The past decade has seen significant progress in understanding galaxy formation and evolution using large-scale cosmological simulations. While these simulations produce galaxies in overall good agreement with observations, they employ different sub-grid models for galaxies and supermassive black holes (BHs). We investigate the impact of the sub-grid models on the BH mass properties of the Illustris, TNG100, TNG300, Horizon-AGN, EAGLE, and SIMBA simulations, focusing on the M_BH-M_star relation and the BH mass function. All simulations predict tight M_BH-M_star relations, and struggle to produce the lowest (M_BH< 10^7.5 Msun) in galaxies of M_star~10^10.5-10^11.5 Msun. While the time evolution of the mean M_BH-M_star relation is mild (10^9 Msun in most of the simulations. The BH mass function is dominated by efficiently accreting BHs (log10 f_Edd >-2$) at high redshifts, and transitions progressively from the high-mass to the low-mass end to be governed by inactive BHs. The transition time and the contribution of active BHs are different among the simulations, and can be used to evaluate models against observations., Comment: Published version - MNRAS