Based on very deep photometry, Surface Brightness Fluctuations (SBF) have been traditionally used to determine galaxy distances. We have recently computed SBF spectra of stellar populations at moderately high resolution, which are fully based on empirical stars. We show that the SBF spectra provide an unprecedented potential for stellar population studies that, so far, have been tackled on the basis of the mean fluxes. We find that the SBFs are able to unveil metal-poor stellar components at the one percent level, which are not possible to disentangle with the standard analysis. As these metal-poor components correspond to the first stages of the chemical enrichment, the SBF analysis provides stringent constrains on the quenching epoch.

Establishing the role of active galactic nuclei (AGN) during the formation of galaxies remains one of the greatest challenges of galaxy formation theory. Towards addressing this, we summarise our recent work investigating: (1) the physical drivers of ionised outflows and (2) observational signatures of the impact by jets/outflows on star formation and molecular gas content in AGN host galaxies. We confirm a connection between radio emission and extreme ionised gas kinematics in AGN hosts. Emission-line selected AGN are significantly more likely to exhibit ionised outflows (as traced by the [O iii] emission line) if the projected linear extent of the radio emission is confined within the spectroscopic aperture. Follow-up high resolution radio observations and integral field spectroscopy of 10 luminous Type 2 AGN reveal moderate power, young (or frustrated) jets interacting with the interstellar medium. We find that these sources live in highly star forming and gas rich galaxies. Additionally, by combining ALMA-derived dust maps with integral field spectroscopy for eight host galaxies of z ≈ 2 X-ray AGN, we show that Hα emission is an unreliable tracer of star formation. For the five targets with ionised outflows we find no dramatic in-situ shut down of the star formation. Across both of these studies we find that if these AGN do have a negative impact upon their host galaxies, it must be happening on small (unresolved) spatial scales and/or an observable galaxy-wide impact has yet to occur.

We present Gemini Near-Infrared Integral-Field Spectrograph (NIFS) observations of the inner 660 × 660 pc2 of the Seyfert 2 galaxy NGC 1125, which reveals that the emission-line profiles present two kinematic components: a narrow one (σ < 150 km s−1) due to emission of the gas in the disk and a broad component (σ > 150 km s−1) produced by a bipolar outflow, perpendicular to the galaxy’s disk.

In this proceeding I will summarize our on-going observational campaign to characterize Active Galactic Nuclei (AGN) driven ionized gas outflows at z ˜ 2 and assess their impact on galaxy evolution. The results are mostly derived from a recently completed SINFONI/VLT Large Programme named SUPER, conducted with Adaptive Optics to reach a spatial resolution of ˜2 kpc at z ˜ 2.

As part of an on-going study of radio transients in Epoch 1 (2017–2019) of the Very Large Array Sky Survey (VLASS), we have discovered a sample of 0.2 < z < 3.2 active galactic nuclei (AGN) selected in the optical/infrared that have recently brightened dramatically in the radio. These sources would have previously been classified as radio-quiet based on upper limits from the Faint Images of the Radio Sky at Twenty-centimeters (FIRST; 1993-2011) survey; however, they are now consistent with radio-loud quasars. We present a quasi-simultaneous, multi-band (1–18 GHz) VLA follow-up campaign of our sample of AGN with extreme radio variability. We conclude that the radio properties are most consistent with AGN that have recently launched jets within the past few decades, potentially making them among the youngest radio AGN known.

Dust Obscured Galaxies (DOGs) are observed as far as the reionization epoch. Their cosmic density peaks together with the star formation rate. DOGs also rule the star formation in high stellar mass galaxies. In this work we used a chemodynamical model to evolve the amount of dust in galaxies. We ran forty models varying initial mass and both dust formation efficiency and dust production. We find that for high star formation rate systems the accretion dominates the dust evolution and it explains high-z DOGs. Low star formation rate systems are better suited to investigate dust production. Also, we find that a MDust/MGas versus MDust/M* diagram is a good tracer of galaxy evolution.

We present a spectral atlas of 70 type-I AGN with the wavelength ranging 0.4–2.5 μm. For 37 sources, this is the first report of NIR spectroscopy in literature. The sample was constructed to study narrow line Seyfert 1 and quasars, with a large range of line widths (800 km s−1 < FWHM < 4000 km s−1) and Fe II intensities (0.2 < R4570 < 2.8). This work presents partial results of an ongoing project that has the objective of modeling the continuum emission and emission lines in order to derive the physics driven the Eigenvector 1 through a panchromatic spectral analysis, with emphasis on strong to super-strong Fe ii emitters. Our results show that hot dust near the sublimation temperature is necessary to explain the 1μm break of the power law component of the continuum. We estimated the hot dust mass and found a weak or absent correlation with the Fe II intensity. Moreover, we found that low ionisation ions are formed in an outer region of the BLR.

Multi-phase filamentary structures surrounding giant elliptical galaxies at the center of cool-core clusters, the Brightest Cluster Galaxies (BCGs), have been detected from optical to submillimeter wavelengths. The source of the ionisation in the filaments is still debated. Studying the excitation of these structures is key to our understanding of Active Galactic Nuclei (AGN) feedback in general, and more precisely of the impact of environmental and local effects on star formation. One possible contributor to the excitation of the filaments is the thermal radiation from the cooling of the hot plasma surrounding the BCGs, the so-called cooling flow.

Our multi-component photometric decomposition of the largest galaxy sample to date with dynamically-measured black hole masses nearly doubles the number of such galaxies. We have discovered substantially modified scaling relations between the black hole mass and the host galaxy properties, including the spheroid (bulge) stellar mass, the total galaxy stellar mass, and the central stellar velocity dispersion. These refinements partly arose because we were able to explore the scaling relations for various sub-populations of galaxies built by different physical processes, as traced by the presence of a disk, early-type versus late-type galaxies, or a Sérsic versus core-Sérsic spheroid light profile. The new relations appear fundamentally linked with the evolutionary paths followed by galaxies, and they have ramifications for simulations and formation theories involving both quenching and accretion.

Galaxies undergoing ram pressure stripping in clusters are an excellent opportunity to study the effects of environment on both the AGN and the star formation activity. We report here on the most recent results from the GASP survey. We discuss the AGN-ram pressure stripping connection and some evidence for AGN feedback in stripped galaxies. We then focus on the star formation activity, both in the disks and the tails of these galaxies, and conclude drawing a picture of the relation between multi-phase gas and star formation.

In this work, we present preliminary results regarding the nuclear emission lines of a statistically complete sample of 56 early-type galaxies that are part of the Deep Integral Field Spectroscopy View of Nuclei of Galaxies (DIVING3D) Project. All early type galaxies (ETGs) were observed with the Gemini Multi-Object Spectrograph Integral Field Unit (GMOS-IFU) installed on the Gemini South Telescope. We detected emission lines in 93% of the sample, mostly low-ionization nuclear emission-line region galaxies (LINERs). We did not find Transition Objects nor H II regions in the sample. Type 1 objects are seen in ∼23% of the galaxies.

General Relativity has been successfully tested on small scales. However, precise tests on galactic and larger scales have only recently begun. Moreover, the majority of these tests on large scales are based on the measurements of Hubble constant (H0), which is currently under discussion. Collett et al. (2018) implemented a novel test combining lensing and dynamical mass measurements of a galaxy, which are connected by a γ parameter, and found γ=0.97±0.09, which is consistent with unity, as predicted by GR. We are carrying out this same technique with a second galaxy, SDP.81 at z=0.299, and present here our preliminary results.

Gas fueling AGN (Active Galaxy Nuclei) is now traceable at high-resolution with ALMA (Atacama Large Millimeter Array) and NOEMA (NOrthern Extended Millimeter Array). Dynamical mechanisms are essential to exchange angular momentum and drive the gas to the super-massive black hole. While at 100pc scale, the gas is sometimes stalled in nuclear rings, recent observations reaching 10pc scale (50mas), may bring smoking gun evidence of fueling, within a randomly oriented nuclear gas disk. AGN feedback is also observed, in the form of narrow and collimated molecular outflows, which point towards the radio mode, or entrainment by a radio jet. Precession has been observed in a molecular outflow, indicating the precession of the radio jet. One of the best candidates for precession is the Bardeen-Petterson effect at small scale, which exerts a torque on the accreting material, and produces an extended disk warp. The misalignment between the inner and large-scale disk, enhances the coupling of the AGN feedback, since the jet sweeps a large part of the molecular disk.

Radio interferometric maps of the blazar AO 0235+164 show the existence of a stationary core, and a compact jet composed of multiple receding components. In this work, we determined the structural characteristics of these jet components (core-component distance, position angle, flux density, etc.) using the statistical method for global optimization Cross-Entropy (CE). The images we analyzed were extracted from public databases, totaling 41 images at 15 GHz and 128 images at 43 GHz. Using criteria such as the value of the CE merit function, and mean residuals, we determined the optimum number of components in each map analyzed in this work. We found that jet components are distributed across all four quadrants on the plane of the sky, indicating a possible non-fixed jet orientation during the monitoring interval. The time evolution of the equatorial coordinates of the jet components were used to determine their respective speeds, ejection epochs, and mean position angles on the plane of the sky. We have identified more than 20 components in the jet of AO 0235+164, with their apparent speeds ranging roughly from 2c to 40c, and distributed across all four quadrants on the plane of the sky. From the kinematics of these jet components we could derive a lower limit of about 39 for its bulk jet Lorentz factor and an upper limit of approximately 42 degrees for its jet viewing angle.

New observations are probing the structures and kinematics of massive galaxies at a much greater level of detail than previously possible, especially during the first half of cosmic history. ALMA data now resolve the distribution of dust and molecular gas in massive galaxies to z ˜ 5. The stellar kinematics of several massive galaxies at z ˜ 2 – 3 have been spatially resolved using gravitational lensing, providing new information on the connection between quenching and morphological transformation. Star formation histories have been reconstructed for growing samples at z ˜ 0.8–2, revealing a wide range of timescales that correlate with galaxies’ sizes and environments, providing evidence for multiple paths to quiescence. I review these and other developments and summarize the insights they have provided into massive galaxies’ evolution.

Nuclear rings are excellent laboratories to study star formation (SF) under extreme conditions. We compiled a sample of 9 galaxies that exhibit bright nuclear rings at 3-33 GHz radio continuum observed with the Jansky Very Large Array, of which 5 are normal star-forming galaxies and 4 are Luminous Infrared Galaxies (LIRGs). Using high frequency radio continuum as an extinction-free tracer of SF, we estimated the size and star formation rate of each nuclear ring and a total of 37 individual circumnuclear star-forming regions. Our results show that majority of the SF in the sample LIRGs take place in their nuclear rings, and circumnuclear SF in local LIRGs are much more spatially concentrated compared to those in the local normal galaxies and previously studied nuclear and extra-nuclear SF in normal galaxies at both low and high redshifts.

We use integral-field spectroscopy obtained with the Gemini instrument GMOS-IFU (Gemini Multi-Object Spectrograph Integral Field Unit) to map the gas distribution, excitation and kinematics in the central kpc of 11 nearby active galaxies. We use channel maps to quantify the ionised gas masses, mass outflow rates and powers of the outflows in order to gauge the feedback effect of these outflows on the host galaxies. We compare this method with others previously used to calculate the feedback power of such outflows.

We mapped the stellar population and emission gas properties in the nuclear region of NGC 6868 using datacubes extracted with Gemini Multi-Object Spectrograph (GMOS) in the Integral Field Unit (IFU) mode. To obtain the star-formation history of this galaxy we used the starlight code together with the new generation of MILES simple stellar population models. The stellar population dominating (95% in light fraction) the central region of NGC 6868 is old and metal rich (~10 Gyr, 2.2 Z⊙). We also derived the kinematics and emission line fluxes of ionized gas with the IFSCube package. A rotation disk is clearly detected in the nuclear region of the galaxy and no broad components were detected. Also, there is a region where the emission lines disappear almost completely, probably due to diffuse ionized gas component. Channel maps, diagnostic diagrams and stellar kinematics are still under analysis.

We have used near-infrared and optical Integral Field Spectroscopy along with optical images to study the inner 100 pc of NGC 4111 in a project to investigate the stellar and gas kinematics in the surroundings of Supermassive Black Holes in nearby galaxies. We have compared the inner stellar and gas kinematics with data of the outer regions of the galaxy. We found larger scale hot ionized gas and warm molecular gas within the inner 100 pc that is in counter-rotation relative to the stellar kinematics, a sign of inflowing material that is probably triggering an Active Galactic Nucleus. This is supported by the nuclear X-ray emission which is heating the molecular gas and causing it to emit. The presence of large amounts of dust in a polar ring suggests that this is a fairly recent event probably due to the capture of a dwarf galaxy.