DSpace Angular :: Browsing by Author "Venturi, G."

Browsing by Author "Venturi, G."

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Bubbles and outflows: The novel JWST/NIRSpec view of the z=1.59 obscured quasar XID2028
(2023) Cresci, G.; Tozzi, G.; Perna, M.; Brusa, M.; Marconcini, C.; Marconi, A.; Carniani, S.; Brienza, M.; Giroletti, M.; Belfiore, F.; Ginolfi, M.; Mannucci, F.; Ulivi, L.; Scholtz, J.; Venturi, G.; Arribas, S.; Ubler, H.; D'Eugenio, F.; Mingozzi, M.; Balmaverde, B.; Capetti, A.; Parlanti, E.; Zana, T.
Quasar feedback in the form of powerful outflows is invoked as a key mechanism to quench star formation in galaxies, although direct observational evidence is still scarce and debated. Here we present Early Release Science JWST NIRSpec IFU observations of the z = 1.59 prototypical obscured Active Galactic Nucleus (AGN) XID2028: This target represents a unique test case for studying quasar feedback at the peak epoch of AGN-galaxy co-evolution because extensive multi-wavelength coverage is available and a massive and extended outflow is detected in the ionised and molecular components. With the unprecedented sensitivity and spatial resolution of the JWST, the NIRSpec dataset reveals a wealth of structures in the ionised gas kinematics and morphology that were previously hidden in the seeing-limited ground-based data. In particular, we find evidence of an interaction between the interstellar medium of the galaxy and the quasar-driven outflow and radio jet that produces an expanding bubble from which the fast and extended wind detected in previous observations emerges. The new observations confirm the complex interplay between the AGN jet, wind and the interstellar medium of the host galaxy, highlighting the role of low-luminosity radio jets in AGN feedback. They also clearly show the new window that NIRSpec opens for detailed studies of feedback at high redshift.
Complex AGN feedback in the Teacup galaxy: a powerful ionised galactic outflow, jet-ISM interaction, and evidence for AGN-triggered star formation in a giant bubble
(2023) Venturi, G.; Treister, Ezequiel; Finlez Ruiz, Carolina; D’Ago, G.; Bauer, F.; Harrison, C. M.; Ramos Almeida, C.; Revalski, M.; Ricci, F.; Sartori, L. F.; Girdhar, A.; Keel, W. C.; Tubín, D.
Context: The z ∼ 0.1 type-2 QSO J1430+1339, known as the “Teacup”, is a complex galaxy showing a loop of ionised gas ∼10 kpc in diameter, co-spatial radio bubbles, a compact (∼1 kpc) jet, and outflow activity. Its closeness offers the opportunity to study in detail the intricate interplaybetween the central supermassive black hole (SMBH) and the material in and around the galaxy, both the interstellar medium (ISM) and circum galactic medium (CGM). Aims: We characterise the spatially resolved properties and effects of the galactic ionised gas outflow and compare them with those of the radio jet and with theoretical predictions to infer its acceleration mechanism.Methods. We used VLT/MUSE optical integral field spectroscopic observations to obtain flux, kinematic, and excitation maps of the extended (up to ∼100 kpc) ionised gas and to characterise the properties of stellar populations. We built radial profiles of the outflow properties as a function ofdistance from the active nucleus, from kiloparsec up to tens of kiloparsec scales, at ∼1 kpc resolution.Results. We detect a velocity dispersion enhancement (&300 km s−1) elongated over several kiloparsecs perpendicular to the radio jet, the active galactic nucleus (AGN) ionisation lobes, and the fast outflow, similar to what is found in other galaxies hosting compact, low-power jets, indicatingthat the jet strongly perturbs the host ISM during its passage. We observe a decreasing trend with distance from the nucleus for the outflow proper ties (mass outflow rate, kinetic rate, momentum rate). The mass outflow rate drops from around 100 M yr−1 in the inner 1–2 kpc to .0.1 M yr−1at 30 kpc. The mass outflow rate of the ionised outflow is significantly higher (∼1–8 times) than the molecular one, in contrast with what is often quoted in AGN. Based on energetic and morphological arguments, the driver of the multi-phase outflow is likely a combination of AGN radiation and the jet, or AGN radiation pressure on dust alone. The outflow mass-loading factor is ∼5–10 and the molecular gas depletion time due to the multi-phase outflow is .108 yr, indicating that the outflow can significantly affect the star formation and the gas reservoir in the galaxy. However, the fraction of the ionised outflow that is able to escape the dark matter halo potential is likely negligible. We detect blue-coloured continuum emission co-spatial with the ionised gas loop. Here, stellar populations are younger (.100–150 Myr) than in the rest of the galaxy (∼0.5–1 Gyr). This constitutes possible evidence for star formation triggered at the edge of the bubble due to the compressing action of the jet and outflow (“positive feedback”), as predicted by theory. All in all, the Teacup constitutes a rich system in which AGN feedback from outflows and jets, in both its negative and positive flavours, co-exist.
Connecting X-ray nuclear winds with galaxy-scale ionised outflows in two z ∼ 1.5 lensed quasars
(2021) Tozzi, G.; Cresci, G.; Marasco, A.; Nardini, E.; Marconi, A.; Mannucci, F.; Chartas, G.; Rizzo, F.; Amiri, A.; Brusa, M.; Comastri, A.; Dadina, M.; Lanzuisi, G.; Mainieri, V.; Mingozzi, M.; Perna, M.; Venturi, G.; Vignali, C.
Aims. Outflows driven by active galactic nuclei (AGN) are expected to have a significant impact on host galaxy evolution, but the matter of how they are accelerated and propagated on galaxy-wide scales is still under debate. This work addresses these questions by studying the link between X-ray, nuclear ultra-fast outflows (UFOs), and extended ionised outflows, for the first time, in two quasars close to the peak of AGN activity (z similar to 2), where AGN feedback is expected to be more effective.Methods. Our selected targets, HS 0810+2554 and SDSS J1353+1138, are two multiple-lensed quasars at z similar to 1.5 with UFO detection that have been observed with the near-IR integral field spectrometer SINFONI at the VLT. We performed a kinematical analysis of the [O III]lambda 5007 optical emission line to trace the presence of ionised outflows.Results. We detected spatially resolved ionised outflows in both galaxies, extended more than 8 kpc and moving up to v>2000 km s(-1). We derived mass outflow rates of similar to 12 M-circle dot yr(-1) and similar to 2 M-circle dot yr(-1) for HS 0810+2554 and SDSS J1353+1138.Conclusions. Compared with the co-hosted UFO energetics, the ionised outflow energetics in HS 0810+2554 is broadly consistent with a momentum-driven regime of wind propagation, whereas in SDSS J1353+1138, it differs by about two orders of magnitude from theoretical predictions, requiring either a massive molecular outflow or a high variability of the AGN activity to account for such a discrepancy. By additionally considering our results together with those from the small sample of well-studied objects (all local but one) having both UFO and extended (ionised, atomic, or molecular) outflow detections, we found that in 10 out of 12 galaxies, the large-scale outflow energetics is consistent with the theoretical predictions of either a momentum- or an energy-driven scenario of wind propagation. This suggests that such models explain the acceleration mechanism of AGN-driven winds on large scales relatively well.
Detailed Accretion History of the Supermassive Black Hole in NGC 5972 over the Past ≳10⁴ yr through the Extended Emission-line Region
(2022) Finlez, C.; Treister, E.; Bauer, F.; Keel, W.; Koss, M.; Nagar, N.; Sartori, L.; Maksym, W. P.; Venturi, G.; Tubin, D.; Harvey, T.
We present integral field spectroscopic observations of NGC 5972 obtained with the Multi-Unit Spectroscopic Explorer at the Very Large Telescope. NGC 5972 is a nearby galaxy containing both an active galactic nucleus (AGN) and an extended emission-line region (EELR) reaching out to similar to 17 kpc from the nucleus. We analyze the physical conditions of the EELR using spatially resolved spectra, focusing on the radial dependence of ionization state together with the light-travel time distance to probe the variability of the AGN on greater than or similar to 10(4) yr timescales. The kinematic analysis suggests multiple components: (a) a faint component following the rotation of the large-scale disk, (b) a component associated with the EELR suggestive of extraplanar gas connected to tidal tails, and (c) a kinematically decoupled nuclear disk. Both the kinematics and the observed tidal tails suggest a major past interaction event. Emission-line diagnostics along the EELR arms typically evidence Seyfert-like emission, implying that the EELR was primarily ionized by the AGN. We generate a set of photoionization models and fit these to different regions along the EELR. This allows us to estimate the bolometric luminosity required at different radii to excite the gas to the observed state. Our results suggest that NGC 5972 is a fading quasar, showing a steady gradual decrease in intrinsic AGN luminosity, and hence the accretion rate onto the SMBH, by a factor similar to 100 over the past 5 x 10(4) yr.
Galaxy-scale ionised winds driven by ultra-fast outflows in two nearby quasars
(2020) Marasco, A.; Cresci, G.; Nardini, E.; Mannucci, F.; Marconi, A.; Tozzi, P.; Tozzi, G.; Amiri, A.; Venturi, G.; Piconcelli, E.; Lanzuisi, G.; Tombesi, F.; Mingozzi, M.; Perna, M.; Carniani, S.; Brusa, M.; Alighieri, S. di Serego
We used MUSE adaptive optics data in narrow field mode to study the properties of the ionised gas in MR 2251-178 and PG 1126-041, two nearby (z similar or equal to 0.06) bright quasars (QSOs) hosting sub-pc scale ultra-fast outflows (UFOs) detected in the X-ray band. We decomposed the optical emission from diffuse gas into a low- and a high-velocity components. The former is characterised by a clean, regular velocity field and a low (similar to 80 km s(-1)) velocity dispersion. It traces regularly rotating gas in PG 1126-041, while in MR 2251-178 it is possibly associated with tidal debris from a recent merger or flyby. The other component is found to be extended up to a few kpc from the nuclei, and shows a high (similar to 800 km s(-1)) velocity dispersion and a blue-shifted mean velocity, as is expected from outflows driven by active galactic nuclei (AGN). We estimate mass outflow rates up to a few M-circle dot yr(-1) and kinetic efficiencies L-KIN/L-BOL between 1-4x10(-4), in line with those of galaxies hosting AGN of similar luminosities. The momentum rates of these ionised outflows are comparable to those measured for the UFOs at sub-pc scales, which is consistent with a momentum-driven wind propagation. Pure energy-driven winds are excluded unless about 100x additional momentum is locked in massive molecular winds. In comparing the outflow properties of our sources with those of a small sample of well-studied QSOs hosting UFOs from the literature, we find that winds seem to systematically lie either in a momentum-driven or an energy-driven regime, indicating that these two theoretical models bracket the physics of AGN-driven winds very well.
Gas, dust, and the CO-to-molecular gas conversion factor in low-metallicity starbursts⋆
(2023) Hunt, L. K.; Belfiore, F.; Lelli, F.; Draine, B. T.; Marasco, A.; Garcia-Burillo, S.; Venturi, G.; Combes, F.; Weiss, A.; Henkel, C.; Menten, K. M.; Annibali, F.; Casasola, V.; Cignoni, M.; McLeod, A.; Tosi, M.; Beltran, M.; Concas, A.; Cresci, G.; Ginolfi, M.; Kumari, N.; Mannucci, F.
The factor relating CO emission to molecular hydrogen column density, X-CO, is still subject to uncertainty, in particular at low metallicity. In this paper, to quantify X-CO at two different spatial resolutions, we exploited a dust-based method together with ALMA 12-m and ACA data and H I maps of three nearby metal-poor starbursts, NGC 625, NGC 1705, and NGC 5253. Dust opacity at 250 pc resolution was derived based on dust temperatures estimated by fitting two-temperature modified blackbodies to Herschel PACS data. By using the HI maps, we were then able to estimate dust-to-gas ratios in the regions dominated by atomic gas, and, throughout the galaxy, to infer total gas column densities and H-2 column densities as the difference with HI. Finally, from the ACA CO(1-0) maps, we derived X-CO. We used a similar technique with 40 pc ALMA 12-m data for the three galaxies, but instead derived dust attenuation at 40 pc resolution from reddening maps based on VLT/MUSE data. At 250 pc resolution, we find X-CO & SIM; 10(22) - 10(23) cm(-2)/K km s(-1), 5-1000 times the Milky Way value, with much larger values than would be expected from a simple metallicity dependence. Instead, at 40 pc resolution, X-CO again shows large variation, but is roughly consistent with a power-law metallicity dependence, given the Z & SIM; 1/3 Z(& ODOT;) metal abundances of our targets. The large scatter in both estimations could imply additional parameter dependence, which we have investigated by comparing X-CO with the observed velocity-integrated brightness temperatures, I-CO, as predicted by recent simulations. Indeed, larger X-CO is significantly correlated with smaller I-CO, but with slightly different slopes and normalizations than predicted by theory. Such behavior can be attributed to the increasing fraction of CO-faint (or dark) H-2 gas with lower spatial resolution (larger beams). This confirms the idea the X-CO is multivariate, depending not only on metallicity but also on the CO brightness temperature and beam size. Future work is needed to consolidate these empirical results by sampling galaxies with different metal abundances observed at varying spatial resolutions.
MAGNUM survey: Compact jets causing large turmoil in galaxies. Enhanced line widths perpendicular to radio jets as tracers of jet-ISM interaction
(2021) Venturi, G.; Cresci, G.; Marconi, A.; Mingozzi, M.; Nardini, E.; Carniani, S.; Mannucci, F.; Marasco, A.; Maiolino, R.; Perna, M.; Treister, E.; Bland-Hawthorn, J.; Gallimore, J.
Context. Outflows accelerated by active galactic nuclei (AGN) are commonly observed in the form of coherent, mildly collimated high-velocity gas directed along the AGN ionisation cones and kinetically powerful (greater than or similar to 10(44-45) erg s(-1)) jets. Recent works found that outflows can also be accelerated by low-power (less than or similar to 10(44) erg s(-1)) jets, and the most recent cosmological simulations indicate that these are the dominant source of feedback on sub-kiloparsec scales, but little is known about their effect on the galaxy host.Aims. We study the relation between radio jets and the distribution and kinematics of the ionised gas in IC 5063, NGC 5643, NGC 1068, and NGC 1386 as part of our survey of nearby Seyfert galaxies called Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM). All these objects host a small-scale (less than or similar to 1 kpc) low-power (less than or similar to 10(44) erg s(-1)) radio jet that has small inclinations (less than or similar to 45 degrees) with respect to the galaxy disc.Methods. We employed seeing-limited optical integral field spectroscopic observations from the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope to obtain flux, kinematic, and excitation maps of the extended ionised gas. We compared these maps with archival radio images and in one case, with Chandra X-ray observations.Results. We detect a strong (up to greater than or similar to 800-1000 km s(-1)) and extended (greater than or similar to 1 kpc) emission-line velocity spread perpendicular to the direction of the AGN ionisation cones and jets in all four targets. The gas excitation in this region of line-width enhancement is entirely compatible with shock ionisation. These broad and symmetric line profiles are not associated with a single coherent velocity of the gas. A 'classical' outflow component with net blueshifted and redshifted motions is also present, but is directed along the ionisation cones and jets.Conclusions. We interpret the observed phenomenon as due to the action of the jets perturbing the gas in the galaxy disc. These intense and extended velocity spreads perpendicular to AGN jets and cones are indeed currently only observed in galaxies hosting a low-power jet whose inclination is sufficiently low with respect to the galaxy disc to impact on and strongly affect its material. In line with cosmological simulations, our results demonstrate that low-power jets are indeed capable of affecting the host galaxy.
MOKA^3D: An innovative approach to 3D gas kinematic modelling I. Application to AGN ionised outflows
(2023) Marconcini, C.; Marconi, A.; Cresci, G.; Venturi, G.; Ulivi, L.; Mannucci, F.; Belfiore, F.; Tozzi, G.; Ginolfi, M.; Marasco, A.; Carniani, S.; Amiri, A.; Di Teodoro, E.; Scialpi, M.; Tomicic, N.; Mingozzi, M.; Brazzini, M.; Moreschini, B.
Studying the feedback process of active galactic nuclei (AGN) requires the characterisation of multiple kinematical components, such as rotating gas and stellar discs, outflows, inflows, and jets. The usual approach to compare the observed galaxy properties with feedback theoretical predictions relies on simplified kinematic models. This allows us to assess the mutual interaction between the galaxy components and determine the energy injection rate into the interstellar medium. However, these models have several limitations, as they often do not take into account projection effects, beam smearing, or the surface brightness distribution of the emitting medium. Here, we present MOKA(3D), an innovative approach to modelling the 3D gas kinematics from integral field spectroscopy observations. In this first paper, we discuss its application to the case of AGN ionised outflows, whose observed clumpy emission and apparently irregular kinematics are only marginally accounted for by the existing kinematical models. Unlike previous works, our model does not assume the surface brightness distribution of the gas, but exploits a novel procedure to derive it from observations by reconstructing the 3D distribution of emitting clouds and providing accurate estimates of the physical properties of spatially resolved outflow (e.g., mass rate, kinetic energy). We demonstrate the capabilities of our method by applying it to three nearby Seyfert-II galaxies observed with the Multi Unit Spectroscopic Explorer (MUSE) at the VLT and selected from the Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM) survey, showing that the complex kinematic features observed can be described by a conical outflow with a constant radial velocity field and a clumpy distribution of clouds.
New multiple AGN systems with subarcsec separation: Confirmation of candidates selected via the novel GMP method
(2023) Ciurlo, A.; Mannucci, F.; Yeh, S.; Amiri, A.; Carniani, S.; Cicone, C.; Cresci, G.; Lusso, E.; Marasco, A.; Marconcini, C.; Marconi, A.; Nardini, E.; Pancino, E.; Rosati, P.; Rubinur, K.; Severgnini, P.; Scialpi, M.; Tozzi, G.; Venturi, G.; Vignali, C.; Volonteri, M.
The existence of multiple active galactic nuclei (AGNs) at small projected distances on the sky is due to either the presence of multiple, inspiraling supermassive black holes, or to gravitational lensing of a single AGN. Both phenomena allow us to address important astrophysical and cosmological questions. However, few kiloparsec-separation multiple AGNs are currently known. Recently, the newly developed Gaia multi-peak (GMP) method provided numerous new candidate members of these populations. We present spatially resolved, integral-field spectroscopy of a sample of four GMP-selected multiple AGN candidates. In all of these systems, we detect two or more components with subarcsec separations. We find that two of the systems are dual AGNs, one is either an intrinsic triple or a lensed dual AGN, while the last system is a chance alignment of an AGN and a star. Our observations double the number of confirmed multiple AGNs at projected separations below 7 kpc at z > 0.5, present the first detection of a possible triple AGN in a single galaxy at z > 0.5, and successfully test the GMP method as a novel technique to discover previously unknown multiple AGNs.
Properties of the multiphase outflows in local (ultra)luminous infrared galaxies
(2021) Fluetsch, A.; Maiolino, R.; Carniani, S.; Arribas, S.; Belfiore, F.; Bellocchi, E.; Cazzoli, S.; Cicone, C.; Cresci, G.; Fabian, A. C.; Gallagher, R.; Ishibashi, W.; Mannucci, F.; Marconi, A.; Perna, M.; Sturm, E.; Venturi, G.
Galactic outflows are known to consist of several gas phases; however, the connection between these phases has been investigated little and only in a few objects. In this paper, we analyseMulti Unit Spectroscopic Explorer (MUSE)/Very Large Telescope (VLT) data of 26 local (U)LIRGs and study their ionized and neutral atomic phases. We also include objects from the literature to obtain a sample of 31 galaxies with spatially resolved multiphase outflow information. We find that the ionized phase of the outflows has on average an electron density three times higher than the disc (n(e,disc) similar to 145 cm(-3) versus n(e,outflow) similar to 500 cm(-3)), suggesting that cloud compression in the outflow is more important than cloud dissipation. We find that the difference in extinction between outflow and disc correlates with the outflow gas mass. Together with the analysis of the outflow velocities, this suggests that at least some of the outflows are associated with the ejection of dusty clouds from the disc. This may support models where radiation pressure on dust contributes to driving galactic outflows. The presence of dust in outflows is relevant for potential formation of molecules inside them. We combine our data with millimetre data to investigate the molecular phase. We find that the molecular phase accounts for more than 60 per cent of the total mass outflow rate in most objects and this fraction is higher in active galactic nuclei (AGN)-dominated systems. The neutral atomic phase contributes of the order of 10 per cent, while the ionized phase is negligible. The ionized-to-molecular mass outflow rate declines slightly with AGN luminosity, although with a large scatter.
Raining in MKW 3 s: A Chandra-MUSE Analysis of X-Ray Cold Filaments around 3CR 318.1
(2021) Jimenez-Gallardo, A.; Massaro, F.; Balmaverde, B.; Paggi, A.; Capetti, A.; Forman, W. R.; Kraft, R. P.; Baldi, R. D.; Mahatma, V. H.; Mazzucchelli, C.; Missaglia, V.; Ricci, F.; Venturi, G.; Baum, S. A.; Liuzzo, E.; O'Dea, C. P.; Prieto, M. A.; Rottgering, H. J. A.; Sani, E.; Sparks, W. B.; Tremblay, G. R.; van Weeren, R. J.; Wilkes, B. J.; Harwood, J. J.; Mazzotta, P.; Kuraszkiewicz, J.
We present the analysis of X-ray and optical observations of gas filaments observed in the radio source 3CR 318.1, associated with NGC 5920, the brightest cluster galaxy (BCG) of MKW 3 s, a nearby cool core galaxy cluster. This work is one of the first X-ray and optical analyses of filaments in cool core clusters carried out using MUSE observations. We aim at identifying the main excitation processes responsible for the emission arising from these filaments. We complemented the optical VLT/MUSE observations, tracing the colder gas phase, with X-ray Chandra observations of the hotter highly ionized gas phase. Using the MUSE observations, we studied the emission line intensity ratios along the filaments to constrain the physical processes driving the excitation, and, using the Chandra observations, we carried out a spectral analysis of the gas along these filaments. We found a spatial association between the X-ray and optical morphology of these filaments, which are colder and have lower metal abundance than the surrounding intracluster medium (ICM), as already seen in other BCGs. Comparing with previous results from the literature for other BCGs, we propose that the excitation process that is most likely responsible for these filaments emission is a combination of star formation and shocks, with a likely contribution from self-ionizing, cooling ICM. Additionally, we conclude that the filaments most likely originated from AGN-driven outflows in the direction of the radio jet.
Shaken, but not expelled: Gentle baryonic feedback from nearby starburst dwarf galaxies
(2023) Marasco, A.; Belfiore, F.; Cresci, G.; Lelli, F.; Venturi, G.; Hunt, L. K.; Concas, A.; Marconi, A.; Mannucci, F.; Mingozzi, M.; McLeod, A. F.; Kumari, N.; Carniani, S.; Vanzi, L.; Ginolfi, M.
Baryonic feedback is expected to play a key role in regulating the star formation of low-mass galaxies by producing galaxy-scale winds associated with mass-loading factors of beta similar to 1-50. We test this prediction using a sample of 19 nearby systems with stellar masses of 10(7) M-star/M-circle dot < 10(10), mostly lying above the main sequence of star-forming galaxies. We used MUSE at VLT optical integral field spectroscopy to study the warm ionised gas kinematics of these galaxies via a detailed modelling of their H alpha emission line. The ionised gas is characterised by irregular velocity fields, indicating the presence of non-circular motions of a few tens of km s(-1) within galaxy discs, but with intrinsic velocity dispersion of 40-60 km s(-1) that are only marginally larger than those measured in main-sequence galaxies. Galactic winds, defined as gas at velocities larger than the galaxy escape speed, encompass only a few percent of the observed fluxes. Mass outflow rates and loading factors are strongly dependent on M-star, the star formation rate (SFR), SFR surface density, and specific SFR (sSFR). For M-star of 10(8) M-circle dot we find beta similar or equal to 0.02, which is more than two orders of magnitude smaller than the values predicted by theoretical models of galaxy evolution. In our galaxy sample, baryonic feedback stimulates a gentle gas cycle rather than causing a large-scale blow-out.
The Cavity of 3CR 196.1: Hα Emission Spatially Associated with an X-Ray Cavity
(2022) Jimenez-Gallardo, A.; Sani, E.; Ricci, F.; Mazzucchelli, C.; Balmaverde, B.; Massaro, F.; Capetti, A.; Forman, W. R.; Kraft, R. P.; Venturi, G.; Gendron-Marsolais, M.; Prieto, M. A.; Marconi, A.; Pena-Herazo, H. A.; Baum, S. A.; O'Dea, C. P.; Lovisari, L.; Gilli, R.; Torresi, E.; Paggi, A.; Missaglia, V.; Tremblay, G. R.; Wilkes, B. J.
We present a multifrequency analysis of the radio galaxy 3CR 196.1 (z=0.198), associated with the brightest galaxy of the cool-core cluster CIZAJ0815.4-0303. This nearby radio galaxy shows a hybrid radio morphology and an X-ray cavity, all signatures of a turbulent past activity, potentially due to merger events and active galactic nuclei (AGN) outbursts. We present results of the comparison between Chandra and Very Large Telescope Multi-Unit Spectroscopic Explorer data for the inner region of the galaxy cluster, on a scale of tens of kpc. We discovered H alpha + [N ii]lambda 6584 emission spatially associated with the X-ray cavity (at similar to 10 kpc from the galaxy nucleus) instead of with its rim. This result differs from previous discoveries of ionized gas surrounding X-ray cavities in other radio galaxies harbored in galaxy clusters and could represent the first reported case of ionized gas filling an X-ray cavity, either due to different AGN outbursts or to the cooling of warm (10(4) < T <= 10(7) K) AGN outflows. We also found that the H alpha, [N ii]lambda lambda 6548, 6584, and [S ii]lambda lambda 6718, 6733 emission lines show an additional redward component, at similar to 1000 km s(-1) from rest frame, with no detection in H beta or [O iii]lambda lambda 4960, 5008. We believe the most likely explanation for this redward component is the presence of a background gas cloud as there appears to be a discrete difference of velocities between this component and the rest frame.
The MURALES survey IV. Searching for nuclear outflows in 3C radio galaxies at z < 0.3 with MUSE observations
(2021) Speranza, G.; Balmaverde, B.; Capetti, A.; Massaro, F.; Tremblay, G.; Marconi, A.; Venturi, G.; Chiaberge, M.; Baldi, R. D.; Baum, S.; Grandi, P.; Meyer, E. T.; O'Dea, C.; Sparks, W.; Terrazas, B. A.; Torresi, E.
We analyze VLT/MUSE observations of 37 radio galaxies from the Third Cambridge catalogue (3C) with redshift < 0.3 searching for nuclear outflows of ionized gas. These observations are part of the MURALES project (a MUse RAdio Loud Emission line Snapshot survey), whose main goal is to explore the feedback process in the most powerful radio-loud AGN. We applied a nonparametric analysis to the [O III] lambda 5007 emission line, whose asymmetries and high-velocity wings reveal signatures of outflows. We find evidence of nuclear outflows in 21 sources, with velocities between similar to 400 and 1000 km s(-1), outflowing masses of similar to 10(5) - 10(7) M-circle dot, and a kinetic energy in the range similar to 10(53) - 10(56) erg. In addition, evidence for extended outflows is found in the 2D gas velocity maps of 13 sources of the subclasses of high-excitation (HEG) and broad-line (BLO) radio galaxies, with sizes between 0.4 and 20 kpc. We estimate a mass outflow rate in the range 0.4-30 M-circle dot yr(-1) and an energy deposition rate of (E)over dot(kin) similar to 10(42) - 10(45) erg s(-1). Comparing the jet power, the nuclear luminosity of the active galactic nucleus, and the outflow kinetic energy rate, we find that outflows of HEGs and BLOs are likely radiatively powered, while jets likely only play a dominant role in galaxies with low excitation. The low loading factors we measured suggest that these outflows are driven by momentum and not by energy. Based on the gas masses, velocities, and energetics involved, we conclude that the observed ionized outflows have a limited effect on the gas content or the star formation in the host. In order to obtain a complete view of the feedback process, observations exploring the complex multiphase structure of outflows are required.
The MURALES survey V. Jet-induced star formation in 3C 277.3 (Coma A)
(2022) Capetti, A.; Balmaverde, B.; Tadhunter, C.; Marconi, A.; Venturi, G.; Chiaberge, M.; Baldi, R. D.; Baum, S.; Gilli, R.; Grandi, P.; Meyer, E. T.; Miley, G.; O'Dea, C.; Sparks, W.; Torresi, E.; Tremblay, G.
We present observations obtained with the VLT/MUSE optical integral field spectrograph of the radio source 3C 277.3, located at a redshift of 0.085 and associated with the galaxy Coma A. An emission line region fully enshrouds the double-lobed radio source, which is similar to 60 kpc x 90 kpc in size. Based on the emission line ratios, we identified five compact knots in which the gas ionization is powered by young stars located as far as similar to 60 kpc from the host. The emission line filaments surrounding the radio emission are compatible with ionization from fast shocks (with a velocity of 350-500 km s(-1)), but a contribution from star formation occurring at the edges of the radio source is likely. Coma A might be a unique example in the local Universe in which the expanding outflow triggers star formation throughout the whole radio source.
The MURALES survey VI. Properties and origin of the extended line emission structures in radio galaxies
(2022) Balmaverde, B.; Capetti, A.; Baldi, R. D.; Baum, S.; Chiaberge, M.; Gilli, R.; Jimenez-Gallardo, A.; Marconi, A.; Massaro, F.; Meyer, E.; O'Dea, C.; Speranza, G.; Torresi, E.; Venturi, G.
This is the sixth paper presenting the results of the MUse RAdio Loud Emission line Snapshot survey. We observed 37 radio sources from the 3C sample with z < 0.3 and a declination <20 degrees with the Multi Unit Spectroscopic Explorer optical integral field spectrograph at the Very Large Telescope. Here, we focus on the properties of the extended emission line regions (EELRs) that can be studied with unprecedented detail thanks to the depth of these observations. Line emission in the ten FR Is is, in most cases, confined to within less than or similar to 4kpc, while large-scale (greater than or similar to 4 kpc) ionized gas is seen in all but two of the 26 FR Its. It usually takes the form of elongated or filamentary structures, typically extending between 10 and 30 kpc, but also reaching distances of similar to 80 kpc. We find that the large-scale ionized gas structures show a tendency to be oriented at large angles from the radio axis, and that the gas on a scale of a few kiloparsecs from the nucleus often shows ordered rotation with a kinematical axis forming a median angle of 65 degrees with the radio axis. We also discuss the velocity field and ionization properties of the EELRs. The observed emission line structures appear to be associated with gaseous "superdisks" that formed after a gas-rich merger. The different properties of the EELR can be explained with a combination of the source evolutionary state and the orientation of the superdisk with respect to the radio axis. The general alignment between the superdisks and radio axis might be produced by stable and coherent accretion maintained over long timescales.

Browsing by Author "Venturi, G."

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