197 results on '"Nucleo galatico"'
Search Results
2. Gas inflows in the polar ring of NGC 4111 : the birth of an AGN
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Roier, Gabriel Roberto Hauschild, Storchi-Bergmann, Thaisa, McDermid, Richard, Walsh, Jonelle, Tan, Joanne, Cohn, Jonathan, Krajnovic, Davor, Greene, Jenny E., Valluri, Monica, Gültekin, Kayhan, Thater, Sabine, Ven, Glenn van de, Gebhardt, Karl, Lützgendorf, Nora, Boizelle, Benjamin, Ma, Chung-Pei, and Barth, Aaron J.
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Galáxias ativas ,Nuclei [Galaxies] ,Cinemática ,Individual : NGC 4111 [Galaxies] ,Gas ionizado ,Nucleo galatico ,Active [Galaxies] ,Kinematics and dynamics [Galaxies] - Abstract
We have used Hubble Space Telescope (HST) images, SAURON Integral Field Spectroscopy (IFS), and adaptative optics assisted Gemini NIFS near-infrared K-band IFS to map the stellar and gas distribution, excitation and kinematics of the inner few kpc of the nearby edge-on S0 galaxy NGC 4111. The HST images map its ≈450 pc diameter dusty polar ring, with an estimated gas mass ≥107 M . The NIFS data cube maps the inner 110 pc radius at ≈7 pc spatial resolution, revealing a ≈220 pc diameter polar ring in hot (2267 ± 166 K) molecular H2 1–0 S(1) gas embedded in the polar ring. The stellar velocity field shows disc-dominated kinematics along the galaxy plane both in the SAURON large scale and in the NIFS nuclear-scale data. The large-scale [O III] λ5007 Å velocity field shows a superposition of two disc kinematics: one similar to that of the stars and another along the polar ring, showing non-circular motions that seem to connect with the velocity field of the nuclear H2 ring, whose kinematics indicate accelerated inflow to the nucleus. The estimated mass inflow rate is enough not only to feed an active galactic nucleus (AGN) but also to trigger circumnuclear star formation in the near future. We propose a scenario in which gas from the polar ring, which probably originated from the capture of a dwarf galaxy, is moving inwards and triggering an AGN, as supported by the local X-ray emission, which seems to be the source of the H2 1–0 S(1) excitation. The fact that we see neither near-UV nor Br γ emission suggests that the nascent AGN is still deeply buried under the optically thick dust of the polar ring.
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- 2022
3. BASS XXXI : outflow scaling relations in low redshift X-ray AGN host galaxies with MUSE
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Kakkad, Darshan, Mallmann, Nícolas Dullius, Riffel, Rogério, and Urry, C. Megan
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Galáxias ativas ,Evolution [Galaxies] ,Nuclei [Galaxies] ,Seyfert [Galaxies] ,Evolucao galatica ,Cinemática ,Gas ionizado ,Nucleo galatico ,Active [Galaxies] ,Kinematics and dynamics [Galaxies] - Abstract
Ionized gas kinematics provide crucial evidence of the impact that active galactic nuclei (AGNs) have in regulating star formation in their host galaxies. Although the presence of outflows in AGN host galaxies has been firmly established, the calculation of outflow properties such as mass outflow rates and kinetic energy remains challenging. We present the [O III]λ5007 ionized gas outflow properties of 22 z
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- 2022
4. Gemini NIFS survey of feeding and feedback in nearby active galaxies V. Molecular and ionized gas kinematics
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Bianchin, Marina, Riffel, Rogemar André, Storchi-Bergmann, Thaisa, Riffel, Rogério, Dutra, Daniel Ruschel, Harrison, Chris, Hahn, Luis Gabriel Dahmer, Mainieri, Vincenzo, Schönell Júnior, Astor João, and Dametto, Natacha Zanon
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Galáxias ativas ,Nuclei [Galaxies] ,Seyfert [Galaxies] ,Cinemática ,Kinematics and Dynamics [Galaxies] ,Nucleo galatico ,Galaxias seyfert ,Active [Galaxies] - Abstract
We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43 ≤ log Lbol ≤ 44.83) nearby (0.004 ≤ z ≤ 0.014) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph (NIFS) in the J (1.25μm) and K (2.2μm) bands. We analyse the most intense emission lines detected on these spectral wavebands: [Fe ii] 1.2570μm and Paβ, which trace the ionized gas in the partially and fully ionized regions, and H2 2.1218μm, which traces the hot (∼2000 K) molecular gas. The dominant kinematic component is rotation in the disc of the galaxies, except for the ionized gas in NGC 5899 that shows only weak signatures of a disc component. We find ionized gas outflow in four galaxies, while signatures of H2 outflows are seen in three galaxies. The ionized gas outflows display velocities of a few hundred km s−1, and their mass outflow rates are in the range 0.005–12.49 M⊙ yr−1. Their kinetic powers correspond to 0.005–0.7 per cent of the active galactic nuclei (AGN) bolometric luminosities. Besides rotation and outflows signatures in some cases, the H2 kinematics also reveals inflows in three galaxies. The inflow velocities are 50–80 km s−1 and the mass inflow rates are in the range 1–9 × 10−4 M⊙ yr−1 for hot molecular gas. These inflows might be only the hot skin of the total inflowing gas, which is expected to be dominated by colder gas. The mass inflow rates are lower than the current accretion rates to the AGN, and the ionized outflows are apparently disturbing the gas in the inner kpc.
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- 2022
5. Optical properties of Peaked Spectrum radio sources
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Nascimento, Raquel Santiago, Rodriguez-Ardila, Alberto, Hahn, Luis Gabriel Dahmer, Faria, Marcos Antonio Fonseca, Riffel, Rogério, Oliveira, Murilo Marinello Assis de, Beuchert, Tobias, and Callingham, Joseph
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Galáxias ativas ,Nuclei [Galaxies] ,ISM [Galaxies] ,Nucleo galatico ,Propriedades óticas ,Active [Galaxies] - Abstract
In this work, we study the optical properties of compact radio sources selected from the literature in order to determine the impact of the radio-jet in their circumnuclear environment. Our sample includes 58 Compact Steep Spectrum (CSS) and GigaHertz Peaked Spectrum (GPS) and 14 Megahertz-Peaked spectrum (MPS) radio sources located at z ≤ 1. The radio luminosity (LR) of the sample varies between Log LR ∼ 23.2 and 27.7 W Hz−1. We obtained optical spectra for all sources from SDSS-DR12 and performed a stellar population synthesis using the STARLIGHT code. We derived stellar masses (M ), ages t , star formation rates (SFR), metallicities Z and internal reddening AV for all young AGNs of our sample. A visual inspection of the SDSS images was made to assign a morphological class for each source. Our results indicate that the sample is dominated by intermediate to old stellar populations and there is no strong correlation between optical and radio properties of these sources. Also, we found that young AGNs can be hosted by elliptical, spiral and interacting galaxies, confirming recent findings. When comparing the optical properties of CSS/GPS and MPS sources, we do not find any significant difference. Finally, the Mid-Infrared WISE colours analysis suggests that the compact radio sources defined as powerful AGNs are, in general, gas-rich systems.
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- 2022
6. Termination shocks and the extended X-ray emission in Mrk 78
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Francesca M. Fornasini, Martin Elvis, W. Peter Maksym, Giuseppina Fabbiano, Thaisa Storchi Bergmann, Poshak Gandhi, and Mark Whittle
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Active galactic nuclei ,Seyfert galaxies ,X-ray active galactic nuclei ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Markarian galaxies ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxias seyfert ,Galáxias ativas ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Active galaxies ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics::Galaxy Astrophysics ,Nucleo galatico - Abstract
Sub-arcsecond imaging of the X-ray emission in the type 2 AGN Mrk 78 with Chandra shows complex structure with spectral variations on scales from $\sim$200 pc to $\sim$ 2 kpc. Overall the X-ray emission is aligned E-W with the radio (3.6 cm) and narrow emission line region as mapped in [OIII], with a marked E-W asymmetry. The Eastern X-ray emission is mostly in a compact knot coincident with the location where the radio source is deflected, while the Western X-ray emission forms a loop or shell $\sim$2 kpc from the nucleus with radius $\sim$0.7 kpc. There is suggestive evidence of shocks in both the Eastern knot and the Western arc. Both these positions coincide with large changes in the velocities of the [OIII] outflow. We discuss possible reasons why the X-ray shocks on the Western side occur $\sim1$ kpc farther out than on the Eastern side. We estimate that the thermal energy injected by the shocks into the interstellar medium corresponds to $0.05-0.6$% of the AGN bolometric luminosity., Comment: 23 pages, 14 figures, 6 tables
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- 2022
7. Stellar populations in local AGNs : evidence for enhanced star formation in the inner 100 pc
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Hahn, Luis Gabriel Dahmer, Riffel, Rogério, Rodriguez-Ardila, Alberto, Riffel, Rogemar André, Storchi-Bergmann, Thaisa, Oliveira, Murilo Marinello Assis de, Davies, Richard I., Burtscher, Leonard, Dutra, Daniel Ruschel, and Rosario, David
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Seyfert [Galaxies] ,imaging spectroscopy [Techniques] ,nuclei [Galaxies] ,Espectroscopia ,Formacao de estrelas ,star formation [Galaxies] ,Galaxias seyfert ,Nucleo galatico - Abstract
In modern models and simulations of galactic evolution, the star formation in massive galaxies is regulated by an ad hoc active galactic nuclei (AGN) feedback process. However, the physics and the extension of such effects on the star formation history of galaxies is matter of vivid debate. In order to shed some light in the AGN effects over the star formation, we analysed the inner 500 × 500 pc of a sample of 14 Seyfert galaxies using GMOS and MUSE integral field spectroscopy. We fitted the continuum spectra in order to derive stellar age, metallicity, velocity, and velocity dispersion maps in each source. After stacking our sample and averaging their properties, we found that the contribution of young SP, as well as that of AGN featureless continuum both peak at the nucleus. The fraction of intermediate-age SPs is smaller in the nucleus if compared to outer regions, and the contribution of old SPs vary very little within our field of view (FoV). We also found no variation of velocity dispersion or metallicity within our FoV. Lastly, we detected an increase in the dust reddening towards the center of the galaxies. These results lead us to conclude that AGN phenomenon is usually related to a recent star formation episode in the circumnuclear region.
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- 2022
8. AGNIFS survey of local AGN: GMOS-IFU data and outflows in 30 sources
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B. Dall'Agnol de Oliveira, D. Lena, D. Ruschel-Dutra, Andrew Robinson, Rogemar A. Riffel, Martin Elvis, Allan Schnorr-Müller, Thaisa Storchi-Bergmann, and Neil M. Nagar
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Seyfert [Galaxies] ,Active galactic nucleus ,Astronomy ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Luminosity ,Nuclei [Galaxies] ,Ionization ,0103 physical sciences ,Galaxy formation and evolution ,Cinemática ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Line (formation) ,Kinematics and dynamics [Galaxies] ,Physics ,010308 nuclear & particles physics ,Order (ring theory) ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Galaxias seyfert ,Active [Galaxies] ,Orientation (vector space) ,Galáxias ativas ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Nucleo galatico - Abstract
We analyse optical datacubes of the inner kiloparsec of 30 local ($z\le0.02$) active galactic nuclei (AGN) hosts that our research group, AGNIFS, has collected over the past decade via observations with the integral field units of the Gemini Multi-Object Spectrographs. Spatial resolutions range between $50~{\rm pc}$ and $300~{\rm pc}$ and spectral coverage is from $4800~\mathring{A}$ or $5600~\mathring{A}$ to $7000~\mathring{A}$, at velocity resolutions of $\approx 50~{\rm km~s^{-1}}$. We derive maps of the gas excitation and kinematics, determine the AGN ionisation axis -- which has random orientation relative to the galaxy, and the kinematic major axes of the emitting gas. We find that rotation dominates the gas kinematics in most cases, but is disturbed by the presence of inflows and outflows. Outflows have been found in 21 nuclei, usually along the ionisation axis. The gas velocity dispersion is traced by $W_{80}$ (velocity width encompassing 80 per cent of the line flux), adopted as a tracer of outflows. In 7 sources $W_{80}$ is enhanced perpendicularly to the ionisation axis, indicating lateral expansion of the outflow. We have estimated mass-outflow rates $\dot{M}$ and powers $\dot{E}$, finding median values of $\log\,[\dot{M}/({\rm\,M_\odot\,yr^{-1}})]=-2.1_{-1.0}^{+1.6}$ and $\log\,[\dot{E}/({\rm\,erg\,s^{-1}})]=38.5_{-0.9}^{+1.8}$, respectively. Both quantities show a mild correlation with the AGN luminosity ($L_{\rm AGN}$). $\dot{E}$ is of the order of 0.01 $L_{\rm AGN}$ for 4 sources, but much lower for the majority (9) of the sources, with a median value of $\log\,[\dot{E}/L_{\rm AGN}]=-5.34_{-0.9}^{+3.2}$ indicating that typical outflows in the local Universe are unlikely to significantly impact their host galaxy evolution.
- Published
- 2021
9. Destruction and multiple ionization of PAHs by X-rays in circumnuclear regions of AGNs
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Alexsandre F. Lago, Felipe Fantuzzi, Dinalva A. Sales, Heloisa M. Boechat-Roberty, Heidy M Quitián-Lara, Thiago Monfredini, Wania Wolff, E. Mendoza, and Miriani Griselda Pastoriza
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Astrochemistry ,Active galactic nucleus ,Infrared ,FOS: Physical sciences ,Photoionization ,Astrophysics ,Photon energy ,010402 general chemistry ,01 natural sciences ,Ionization ,0103 physical sciences ,Optical depth (astrophysics) ,010303 astronomy & astrophysics ,Astroquímica ,Physics ,Molecular data ,Order (ring theory) ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,galaxies [X-rays] ,0104 chemical sciences ,Hidrocarbonetos aromáticos policíclicos ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Nucleo galatico - Abstract
The infrared signatures of polycyclic aromatic hydrocarbons (PAHs) are observed in a variety of astrophysical objects, including the circumnuclear medium of active galactic nuclei (AGNs). These are sources of highly energetic photons (0.2 to 10 keV), exposing the PAHs to a harsh environment. In this work, we examined experimentally the photoionization and photostability of naphthalene (C$_{10}$H$_{8}$), anthracene (C$_{14}$H$_{10}$), 2-methyl-anthracene (C$_{14}$H$_{9}$CH$_{3}$) and pyrene (C$_{16}$H$_{10}$) upon interaction with photons of 275, 310 and 2500 eV. The measurements were performed at the Brazilian Synchrotron Light Laboratory using time-of-flight mass-spectrometry (TOF-MS). We determined the absolute photoionization and photodissociation cross sections as a function of the incident photon energy; the production rates of singly, doubly and triply charged ions; and the molecular half-lives in regions surrounding AGNs. Even considering moderate X-ray optical depth values ($\tau = 4.45$) due to attenuation by the dusty torus, the half-lives are not long enough to account for PAH detection. Our results suggest that a more sophisticated interplay between PAHs and dust grains should be present in order to circumvent molecular destruction. We could not see any significant difference in the half-life values by increasing the size of the PAH carbon backbone, N$_C$, from 10 to 16. However, we show that the multiple photoionization rates are significantly greater than the single ones, irrespective of the AGN source. We suggest that an enrichment of multiply charged ions caused by X-rays can occur in AGNs., Comment: 20 pages (appendix: 3 pages), 10 figures, 4 tables. Accepted for publication in the Montly Notices of the Royal Astronomical Society (MNRAS). Accepted 2019 April 4
- Published
- 2019
10. LLAMA: Stellar populations in the nuclei of ultra hard X-ray selected AGN and matched inactive galaxies
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Taro Shimizu, Marc Schartmann, E. K. S. Hicks, Rogério Riffel, Richard Davies, David J. Rosario, Rogemar A. Riffel, Thaisa Storchi-Bergmann, Allan Schnorr-Müller, Leonard Burtscher, Ming-yi Lin, G. Orban de Xivry, and Sylvain Veilleux
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Seyfert [Galaxies] ,Active galactic nucleus ,Stellar mass ,Stellar population ,Active ,Evolution ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Spectroscopic ,Spectral line ,Stellar Content ,Evolution [Galaxies] ,Nuclei [Galaxies] ,Evolucao galatica ,Astrophysics::Solar and Stellar Astrophysics ,education ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,Stellar content [Galaxies] ,Star formation ,Astronomy and Astrophysics ,Radius ,Galaxies ,Nuclei ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Techniques ,Galaxias seyfert ,Active [Galaxies] ,Galáxias ativas ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Seyfert ,Spectroscopic [Techniques] ,Astrophysics::Earth and Planetary Astrophysics ,Nucleo galatico - Abstract
The relation between nuclear ($\lesssim$ 50 pc) star formation and nuclear galactic activity is still elusive: theoretical models predict a link between the two, but it is unclear whether active galactic nuclei (AGNs) should appear at the same time, before or after nuclear star formation activity is ongoing. We present a study of this relation in a complete, volume-limited sample of nine of the most luminous ($\log L_{\rm 14-195 keV} > 10^{42.5}$ erg/s) local AGNs (the LLAMA sample), including a sample of 18 inactive control galaxies (6 star-forming; 12 passive) that are matched by Hubble type, stellar mass (9.5 $\lesssim$ log M_star/M_sun $\lesssim$ 10.5), inclination and distance. This allows us to calibrate our methods on the control sample and perform a differential analysis between the AGN and control samples. We perform stellar population synthesis on VLT/X-SHOOTER spectra in an aperture corresponding to a physical radius of $\approx$ 150 pc. We find young ($\lesssim$ 30 Myr) stellar populations in seven out of nine AGNs and in four out of six star-forming control galaxies. In the non-star-forming control population, in contrast, only two out of twelve galaxies show such a population. We further show that these young populations are not indicative of ongoing star-formation, providing evidence for models that see AGN activity as a consequence of nuclear star formation. Based on the similar nuclear star-formation histories of AGNs and star-forming control galaxies, we speculate that the latter may turn into the former for some fraction of their time. Under this assumption, and making use of the volume-completeness of our sample, we infer that the AGN phase lasts for about 5 % of the nuclear starburst phase., 53 pages, 44 figures, accepted for publication by A&A
- Published
- 2021
11. Chemical abundances in Seyfert galaxies : VII. Direct abundance determination of neon based on optical and infrared emission lines
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Armah, Mark, Dors Júnior, Oli Luiz, Aydar, Catarina, Cardaci, Mónica V., Hägelle, Guillermo Federico, Feltre, Anna, Riffel, Rogério, Riffel, Rogemar André, and Krabbe, Angela Cristina
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Galáxias ativas ,abundances [ISM] ,Seyfert [Galaxies] ,active [Galaxies] ,nuclei [Galaxies] ,Abundância estelar ,Evolucao galatica ,abundances [Galaxies] ,evolution [Galaxies] ,Nucleo galatico ,Galaxias seyfert - Abstract
For the first time, neon abundance has been derived in the narrow line region from a sample of Seyfert 2 nuclei. In view of this, we compiled from the literature fluxes of optical and infrared (IR) narrow emission lines for 35 Seyfert 2 nuclei in the local universe (z 0.06). The relative intensities of emission lines were used to derive the ionic and total neon and oxygen abundances through electron temperature estimations (Te-method). For the neon, abundance estimates were obtained by using both Te-method and IR-method. Based on photoionization model results, we found a lower electron temperature [te(Ne iii)] for the gas phase where the Ne2 + is located in comparison with t3 for the O2 + ion. We find that the differences (D) between Ne2 +/H+ ionic abundances calculated from IR-method and Te-method (assuming t3 in the Ne2 +/H+ derivation) are similar to the derivations in star-forming regions (SFs) and they are reduced by a mean factor of ∼3 when te(Ne iii) is considered. We propose a semi-empirical Ionization Correction Factor (ICF) for the neon, based on [Ne II]12.81μm, [Ne III]15.56μm, and oxygen ionic abundance ratios. We find that the average Ne/H abundance for the Seyfert 2s sample is nearly 2 times higher than similar estimate for SFs. Finally, for the very high metallicity regime (i.e. [12 + log(O/H) 8.80]) an increase in Ne/O with O/H is found, which likely indicates secondary stellar production for the neon.
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- 2021
12. Gemini NIFS survey of feeding and feedback in nearby active galaxies : IV. Excitation
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Riffel, Rogemar André, Bianchin, Marina, Riffel, Rogério, Storchi-Bergmann, Thaisa, Schönell Júnior, Astor João, Hahn, Luis Gabriel Dahmer, Dametto, Natacha Zanon, and Diniz, Marlon Rodrigo
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Galáxias ativas ,Nuclei [Galaxies] ,Seyfert [Galaxies] ,ISM [Galaxies] ,Nucleo galatico ,Galaxias seyfert ,Active [Galaxies] - Abstract
The near-infrared spectra of active galactic nuclei (AGN) present emission lines of different atomic and molecular species. The mechanisms involved in the origin of these emission lines in AGN are still not fully understood. We use J- and K-band integral field spectra of six luminous (43.1 < logLbol/(erg s−1) < 44.4) Seyfert galaxies (NGC 788, Mrk 607, NGC 3227, NGC 3516, NGC 5506, and NGC 5899) in the local Universe (0.0039
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- 2021
13. A Gemini–NIFS view of the merger remnant NGC 34
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Motter, Juliana Cristina, Riffel, Rogério, Ricci, Tiago Vecchi, Riffel, Rogemar André, Storchi-Bergmann, Thaisa, Pastoriza, Miriani Griselda, Rodriguez-Ardila, Alberto, Dutra, Daniel Ruschel, Hahn, Luis Gabriel Dahmer, Dametto, Natacha Zanon, and Diniz, Marlon Rodrigo
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Nuclei [Galaxies] ,Individual : NGC 34 [Galaxies] ,ISM [Galaxies] ,Galaxies [Infrared] ,Cinemática ,Galaxias Starburst ,Galáxia NGC 34 ,Individual : NGC 17 [Galaxies] ,Starburst [Galaxies] ,Nucleo galatico ,Individual : Mrk 938 [Galaxies] - Abstract
The merger remnant NGC 34 is a local luminous infrared galaxy (LIRG) hosting a nuclear starburst and a hard X-ray source associated with a putative, obscured Seyfert 2 nucleus. In this work, we use adaptive optics assisted near-infrared (NIR) integral field unit observations of this galaxy to map the distribution and kinematics of the ionized and molecular gas in its inner 1.2kpc×1.2kpc, with a spatial resolution of 70 pc. The molecular and ionized gas kinematics is consistent with a disc with projected major axis along a mean PA = −9∘.2 ± 0∘.9. Our main findings are that NGC 34 hosts an AGN and that the nuclear starburst is distributed in a circumnuclear star formation ring with inner and outer radii of ≈ 60 and 180 pc, respectively, as revealed by maps of the [FeII]/Paβ and H2/Br γ emission-line ratios, and corroborated by PCA tomography analysis. The spatially resolved NIR diagnostic diagram of NGC 34 also identifies a circumnuclear structure dominated by processes related to the stellar radiation field and a nuclear region where [FeII] and H2 emissions are enhanced relative to the hydrogen recombination lines. We estimate that the nuclear X-ray source can account for the central H2 enhancement and conclude that [FeII] and H2 emissions are due to a combination of photoionization by young stars, excitation by X-rays produced by the AGN and shocks. These emission lines show nuclear, broad, blueshifted components that can be interpreted as nuclear outflows driven by the AGN.
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- 2021
14. The Eddington ratio-dependent changing look events in NGC 2992
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Bradley M. Peterson, D. Ruschel-Dutra, J. S. Schimoia, Rodrigo Nemmen, Dirk Grupe, Andrew Robinson, Thaisa Storchi-Bergmann, and Muryel Guolo
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Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Seyfert [Galaxies] ,Active galactic nucleus ,Accretion (meteorology) ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Type (model theory) ,Astrophysics - Astrophysics of Galaxies ,Galaxias seyfert ,Galaxy ,galaxies [X-rays] ,Luminosity ,Space and Planetary Science ,nuclei [Galaxies] ,Astrophysics of Galaxies (astro-ph.GA) ,Absorption (logic) ,Continuum (set theory) ,Emission spectrum ,Astrophysics - High Energy Astrophysical Phenomena ,Nucleo galatico ,Astrophysics::Galaxy Astrophysics - Abstract
We present an analysis of historical multi-wavelength emission of the Changing Look (CL) Active Galactic Nucleus (AGN) in NGC 2992, covering epochs ranging from 1978 to 2021, as well as new X-ray and optical spectra. The galaxy presents multiple Seyfert type transitions from type 2 to intermediate-type, losing and regaining its H$\alpha$ BEL recurrently. In X-rays, the source shows intrinsic variability with the absorption corrected luminosity varying by a factor of $\sim$ 40. We rule out tidal disruption events or variable obscuration as causes of the type transitions and show that the presence and the flux of the broad H$\alpha$ emission line are directly correlated with the 2-10 keV X-ray luminosity (L$_{2-10}$): the component disappears at L$_{2-10} \leq 2.6\times10^{42}$\ergcms, this value translates into an Eddington ratio ($\lambda_{\rm Edd}$) of $\sim$ 1\%. The $\lambda_{\rm Edd}$ in which the BEL transitions occur is the same as the critical value at which there should be a state transition between a radiatively inefficient accretion flow (RIAF) and a thin accretion disk, such similarity suggests that the AGN is operating at the threshold mass accretion rate between the two accretion modes. We find a correlation between the narrow Fe K$\alpha$ flux and $\lambda_{\rm Edd}$, and an anti-correlation between full-width at half maximum of H$\alpha$ BEL and $\lambda_{\rm Edd}$, in agreement with theoretical predictions. Two possible scenarios for type transitions are compatible with our results: either the dimming of the AGN continuum, which reduces the supply of ionising photons available to excite the gas in the Broad Line Region (BLR), or the fading of the BLR structure itself occurs as the low accretion rate is not able to sustain the required cloud flow rate in a disk-wind BLR model., Comment: Accepted for publication at MNRAS
- Published
- 2021
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15. Chemical abundances in Seyfert galaxies : V. The discovery of shocked emission outside the AGN ionization axis
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Riffel, Rogemar André, Dors Júnior, Oli Luiz, Armah, Mark, Storchi-Bergmann, Thaisa, Feltre, Anna, Hägelle, Guillermo Federico, Cardaci, Mónica V., Dutra, Daniel Ruschel, Krabbe, Angela Cristina, Pérez-Montero, Enrique, Zakamska, Nadia L., and Santos, Izabel Cristina Freitas dos
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Galáxias ativas ,Seyfert [Galaxies] ,ISM [Galaxies] ,Abundances [Galaxies] ,Nucleo galatico ,Galaxias seyfert ,Active [Galaxies] - Abstract
We present maps for the electron temperature in the inner kpc of three luminous Seyfert galaxies: Mrk 79, Mrk 348, and Mrk 607 obtained from Gemini Multi-Object Spectrograph-integral field unit observations at spatial resolutions of ∼110–280 pc. We study the distributions of electron temperature in active galaxies and find temperatures varying in the range from ∼8000 to 30 000 K. Shocks due to gas outflows play an important role in the observed temperature distributions of Mrk 79 and Mrk 348, while standard photoionization models reproduce the derived temperature values for Mrk 607. In Mrk 79 and Mrk 348, we find direct evidence for shock ionization with overall orientation orthogonal to the ionization axis, where shocks can be easily observed as the active galactic nuclei radiation field is shielded by the nuclear dusty torus. This also indicates that even when the ionization cones are narrow, the shocks can be much wider angle.
- Published
- 2021
16. Upper boundaries of active galactic nucleus regions in optical diagnostic diagrams
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Niv Drory, Kai Zhang, Rogério Riffel, Renbin Yan, and Xihan Ji
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Electron density ,Seyfert [Galaxies] ,Active galactic nucleus ,active [Galaxies] ,Metallicity ,Doubly ionized oxygen ,Photoionization ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astronomy & Astrophysics ,01 natural sciences ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Line (formation) ,Physics ,Mapeamentos astronômicos ,010308 nuclear & particles physics ,Diagram ,Astronomy and Astrophysics ,Galaxy ,Galáxias ativas ,Space and Planetary Science ,nuclei [Galaxies] ,Nucleo galatico ,Astronomical and Space Sciences - Abstract
The distribution of galaxies in optical diagnostic diagrams can provide information about their physical parameters when compared with ionization models under proper assumptions. By using a sample of central emitting regions from the Mapping Nearby Galaxies at Apache Point Observatory survey (MaNGA), we find evidence of the existence of upper boundaries for narrow-line regions (NLRs) of active galactic nuclei (AGNs) in optical Baldwin, Phillips & Terlevich (BPT) diagrams, especially in diagrams involving [S ii]λλ6716, 6731/Hα. Photoionization models can reproduce the boundaries well, as a consequence of the decrease of [S ii]λλ6716, 6731/Hα and [O iii]λ5007/Hβ ratios at very high metallicity. Whilst the exact location of the upper boundary in the [S ii] BPT diagram depends only weakly on the electron density of the ionized cloud and the secondary nitrogen prescription, its dependence on the shapes of the input spectral energy distributions (SEDs) is much stronger. This allows us to constrain the power-law index of the AGN SED between 1 Ryd and ∼100 Ryd to be less than or equal to −1.40 ± 0.05. The coverage of photoionization models in the [N ii] BPT diagram has a stronger dependence on the electron density and the secondary nitrogen prescription. With the density constrained by the [S ii] doublet ratio and the input SED constrained by the [S ii] BPT diagram, we find that the extent of the data in the [N ii] BPT diagram favours those prescriptions with high N/O ratios. Although shock-ionized clouds can produce line ratios similar to those from photoionization, the resulting shapes of the upper boundaries, if they exist, would likely be different from those of photoionizing origin.
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- 2020
17. Constraining radio mode feedback in galaxy clusters with the cluster radio AGNs properties to z ∼ 1
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Gupta, Nayantara, Santiago, Basilio Xavier, and Zenteno, Alfredo
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Aglomerados de galaxias ,Galáxias ativas ,galaxies [Submillimeter] ,active [Galaxies] ,Mass function ,Deslocamento para o vermelho ,clusters: general [Galaxies] ,observations [Cosmology] ,luminosity function [Galaxies] ,Nucleo galatico - Abstract
We study the properties of the Sydney University Molonglo Sky Survey (SUMSS) 843 MHz radio active galactic nuclei (AGNs) population in galaxy clusters from two large catalogues created using the Dark Energy Survey (DES): ∼11 800 optically selected RM-Y3 and ∼1000 X-ray selected MARD-Y3 clusters. We show that cluster radio loud AGNs are highly concentrated around cluster centres to z ∼ 1. We measure the halo occupation number for cluster radio AGNs above a threshold luminosity, finding that the number of radio AGNs per cluster increases with cluster halo mass as N ∝ M1.2 ± 0.1 (N ∝ M0.68 ± 0.34) for the RM-Y3 (MARD-Y3) sample. Together, these results indicate that radio mode feedback is favoured in more massive galaxy clusters. Using optical counterparts for these sources, we demonstrate weak redshift evolution in the host broad-band colours and the radio luminosity at fixed host galaxy stellar mass. We use the redshift evolution in radio luminosity to break the degeneracy between density and luminosity evolution scenarios in the redshift trend of the radio AGNs luminosity function (LF). The LF exhibits a redshift trend of the form (1 + z)γ in density and luminosity, respectively, of γD = 3.0 ± 0.4 and γP = 0.21 ± 0.15 in the RM-Y3 sample, and γD = 2.6 ± 0.7 and γP = 0.31 ± 0.15 in MARD-Y3. We discuss the physical drivers of radio mode feedback in cluster AGNs, and we use the cluster radio galaxy LF to estimate the average radio-mode feedback energy as a function of cluster mass and redshift and compare it to the core (
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- 2020
18. Hubble Space Telescope Observations of [O~III] Emission in Nearby QSO2s: Physical Properties of the Ionised Outflows
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Thaisa Storchi-Bergmann, Anna Trindade Falcao, C. M. Gaskell, Travis Fischer, Henrique R. Schmitt, D. M. Crenshaw, Martin Ward, Martin Elvis, S. B. Kraemer, Richard F. Mushotzky, T. J. Turner, Mitchell Revalski, Fred Hamann, Hagai Netzer, Marianne Vestergaard, J. B. Hutchings, and Luis C. Ho
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ACTIVE GALACTIC NUCLEI ,ULTRAVIOLET ,Astrophysics::High Energy Astrophysical Phenomena ,Library science ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,STAR-FORMATION ,Spitzer Space Telescope ,Basic research ,Hubble space telescope ,0103 physical sciences ,Cinemática ,Astrophysics::Solar and Stellar Astrophysics ,Space research ,BLACK-HOLES ,Quasars ,010303 astronomy & astrophysics ,Naval research ,Astrophysics::Galaxy Astrophysics ,SEYFERT-1 GALAXIES ,Kinematics and dynamics [Galaxies] ,Independent research ,Physics ,FEEDBACK ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Quasars [Galaxies] ,Astrophysics - Astrophysics of Galaxies ,Active [Galaxies] ,Galáxias ativas ,NARROW-LINE REGION ,GAS ,Space and Planetary Science ,AGN OUTFLOWS ,Astrophysics of Galaxies (astro-ph.GA) ,Nucleo galatico - Abstract
We use Hubble Space Telescope (HST)/ Space Telescope Imaging Spectrograph (STIS) long-slit G430M and G750M spectra to analyse the extended [O~III] 5007A emission in a sample of twelve nearby (z < 0.12) luminous (L_bol > 1.6 x 10^45 erg s^-1) QSO2s. The purpose of the study is to determine the properties of the mass outflows of ionised gas and their role in AGN feedback. We measure fluxes and velocities as functions of radial distances. Using Cloudy models and ionising luminosities derived from [O~III] 5007A, we are able to estimate the densities for the emission-line gas. From these results, we derive masses of [O~III]-emitting gas, mass outflow rates, kinetic energies, kinetic luminosities, momenta and momentum flow rates as a function of radial distance for each of the targets. For the sample, masses are several times 10^3 - 10^7 solar masses and peak outflow rates are 9.3 x 10^-3 Msun/yr to 10.3 Msun/yr. The peak kinetic luminosities are 3.4 x 10^-8 to 4.9 x 10^-4 of the bolometric luminosity, which does not approach the 5.0 x 10^-3 - 5.0 x 10^-2 range required by some models for efficient feedback. For Mrk 34, which has the largest kinetic luminosity of our sample, in order to produce efficient feedback there would have to be 10 times more [O~III]-emitting gas than we detected at its position of maximum kinetic luminosity. Three targets show extended [O~III] emission, but compact outflow regions. This may be due to different mass profiles or different evolutionary histories., 14 pages, 11 Figures, accepted for publication in the MNRAS
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- 2020
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19. Powerful ionized gas outflows in the interacting radio galaxy 4C+29.30
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Couto, Guilherme dos Santos, Storchi-Bergmann, Thaisa, Siemiginowska, Aneta L., Riffel, Rogemar André, and Morganti, Raffaellla H.
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Galáxias ativas ,active [Galaxies] ,kinematics and dynamics [Galaxies] ,nuclei [Galaxies] ,jets [Galaxies] ,Cinemática estelar ,Nucleo galatico ,individual: 4C+29.30 [Galaxies] - Abstract
We investigate the ionized gas excitation and kinematics in the inner 4.3 × 6.2 kpc2 of the merger radio galaxy 4C+29.30. Using optical integral field spectroscopy with the Gemini North Telescope, we present flux distributions, line-ratio maps, peak velocities and velocity dispersion maps as well as channel maps with a spatial resolution of ≈955 pc. We observe high blueshifts of up to ∼−650 km s−1 in a region ∼1 arcsec south of the nucleus (the southern knot – SK), which also presents high velocity dispersions (∼250 km s−1), which we attribute to an outflow. A possible redshifted counterpart is observed north from the nucleus (the northern knot – NK). We propose that these regions correspond to a bipolar outflow possibly due to the interaction of the radio jet with the ambient gas. We estimate a total ionized gas mass outflow rate of M˙ out = 25.4+11.5 −7.5 M yr−1with a kinetic power of E˙ = 8.1+10.7 −4.0 × 1042 erg s−1, which represents 5.8+7.6 −2.9 per cent of the active galactic nucleus (AGN) bolometric luminosity. These values are higher than usually observed in nearby active galaxies with the same bolometric luminosities and could imply a significant impact of the outflows in the evolution of the host galaxy. The excitation is higher in the NK – that correlates with extended X-ray emission, indicating the presence of hotter gas – than in the SK, supporting a scenario in which an obscuring dust lane is blocking part of the AGN radiation to reach the southern region of the galaxy.
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- 2020
20. LLAMA : the MBH–σ⋆ relation of the most luminous local AGNs
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Francisco Müller-Sánchez, Michael Koss, Allan Schnorr-Müller, E. K. S. Hicks, M. Y. Lin, Jarle Brinchmann, Rogério Riffel, Richard Davies, Turgay Caglar, Gilles Orban de Xivry, T. Taro Shimizu, David J. Rosario, Marc Schartmann, Witold Maciejewski, Bernhard R. Brandl, Rogemar A. Riffel, Vardha N. Bennert, Sylvain Veilleux, Thaisa Storchi-Bergmann, and Leonard Burtscher
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Accretion ,Seyfert [Galaxies] ,Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Bulges [Galaxies] ,Evolution [Galaxies] ,Bulge ,0103 physical sciences ,Emission spectrum ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Supermassive black hole ,010308 nuclear & particles physics ,Velocity dispersion ,Astronomy and Astrophysics ,Black hole physics ,Galaxy ,Accretion (astrophysics) ,Active [Galaxies] ,Black hole ,Galáxias ativas ,Buracos negros ,Space and Planetary Science ,Accretion disks ,Nucleo galatico - Abstract
Context.TheMBH–σ⋆relation is considered a result of coevolution between the host galaxies and their supermassive black holes. For elliptical bulge hosting inactive galaxies, this relation is well established, but there is still discussion concerning whether active galaxies follow the same relation.Aims.In this paper, we estimate black hole masses for a sample of 19 local luminous active galactic nuclei (AGNs; LLAMA) to test their location on theMBH–σ⋆relation. In addition, we test how robustly we can determine the stellar velocity dispersion in the presence of an AGN continuum and AGN emission lines, and as a function of signal-to-noise ratio.Methods.Supermassive black hole masses (MBH) were derived from the broad-line-based relations for Hα, Hβ, and Paβemission line profiles for Type 1 AGNs. We compared the bulge stellar velocity dispersion (σ⋆) as determined from the Ca II triplet (CaT) with the dispersion measured from the near-infrared CO (2-0) absorption features for each AGN and find them to be consistent with each other. We applied an extinction correction to the observed broad-line fluxes and we corrected the stellar velocity dispersion by an average rotation contribution as determined from spatially resolved stellar kinematic maps.Results.The Hα-based black hole masses of our sample of AGNs were estimated in the range 6.34 ≤ logMBH ≤ 7.75M⊙and theσ⋆CaTestimates range between 73 ≤ σ⋆CaT ≤ 227 km s−1. From the so-constructedMBH − σ⋆relation for our Type 1 AGNs, we estimate the black hole masses for the Type 2 AGNs and the inactive galaxies in our sample.Conclusions.We find that our sample of local luminous AGNs is consistent with theMBH–σ⋆relation of lower luminosity AGNs and inactive galaxies, after correcting for dust extinction and the rotational contribution to the stellar velocity dispersion.
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- 2020
21. Host galaxy properties of changing-look AGNs revealed in the MaNGA survey
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Longji Bing, Rogemar A. Riffel, Junqiang Ge, Yanmei Chen, Rogério Riffel, Yong Shi, Xiaoling Yu, Songlin Li, and Jianhang Chen
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Angular momentum ,Seyfert [Galaxies] ,Active galactic nucleus ,active [Galaxies] ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Type (model theory) ,01 natural sciences ,symbols.namesake ,0103 physical sciences ,Evolucao galatica ,Emission spectrum ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,010308 nuclear & particles physics ,Star formation ,kinematics and dynamics [Galaxies] ,Balmer series ,Astronomy and Astrophysics ,evolution [Galaxies] ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Galaxias seyfert ,Galáxias ativas ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,nuclei [Galaxies] ,symbols ,Cinemática estelar ,Nucleo galatico - Abstract
Changing-look Active Galactic Nuclei (CL-AGNs) are a subset of AGNs in which the broad Balmer emission lines appear or disappear within a few years. We use the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey to identify five CL-AGNs. The 2-D photometric and kinematic maps reveal common features as well as some unusual properties of CL-AGN hosts as compared to the AGN hosts in general. All MaNGA CL-AGNs reside in the star-forming main sequence, similar to MaNGA non-changing-look AGNs (NCL-AGNs). The $80\% \pm 16\%$ of our CL-AGNs do possess pseudo-bulge features, and follow the overall NCL-AGNs $M_{BH}-\sigma_{*}$ relationship. The kinematic measurements indicate that they have similar distributions in the plane of angular momentum versus galaxy ellipticity. MaNGA CL-AGNs however show a higher, but not statistically significant ($20\% \pm 16\%$) fraction of counter-rotating features compared to that ($1.84\% \pm 0.61\%$) in general star-formation population. In addition, MaNGA CL-AGNs favor more face-on (axis ratio $>$ 0.7) than that of Type I NCL-AGNs. These results suggest that host galaxies could play a role in the CL-AGN phenomenon., Comment: 11 pages, 4 tables, 4 figures. Accepted for publication in MNRAS
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- 2020
22. Active galactic nuclei winds as the origin of the H$_2$ emission excess in nearby galaxies
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Rogemar A. Riffel, Rogério Riffel, and Nadia L. Zakamska
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Active galactic nucleus ,active [Galaxies] ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Gravitational potential ,Flux (metallurgy) ,Spitzer Space Telescope ,ISM [Galaxies] ,0103 physical sciences ,Cinemática ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,kinematics and dynamics [Galaxies] ,010308 nuclear & particles physics ,Star formation ,Spatially resolved ,Astronomy and Astrophysics ,Plasma ,Meio interestelar ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Galáxias ativas ,Space and Planetary Science ,nuclei [Galaxies] ,Astrophysics of Galaxies (astro-ph.GA) ,Nucleo galatico - Abstract
In most galaxies, the fluxes of rotational H2 lines strongly correlate with star formation diagnostics (such as polycyclic aromatic hydrocarbons, PAH), suggesting that H2 emission from warm molecular gas is a minor byproduct of star formation. We analyse the optical properties of a sample of 309 nearby galaxies derived from a parent sample of 2,015 objects observed with the Spitzer Space Telescope. We find a correlation between the [OI]6300 emission-line flux and kinematics and the H2 S(3)9.665um/PAH11.3um. The [OI]6300 kinematics in Active Galactic Nuclei (AGN) can not be explained only by gas motions due to the gravitational potential of their host galaxies, suggesting that AGN driven outflows are important to the observed kinematics. While H2 excess also correlates with the fluxes and kinematics of ionized gas (probed by [OIII]), the correlation with [OI] is much stronger, suggesting that H2 and [OI] emission probe the same phase or tightly coupled phases of the wind. We conclude that the excess of H2 emission seen in AGN is produced by shocks due to AGN driven outflows and in the same clouds that produce the [OI] emission. Our results provide an indirect detection of neutral and molecular winds and suggest a new way to select galaxies that likely host molecular outflows. Further ground- and space-based spatially resolved observations of different phases of the molecular gas (cold, warm and hot) are necessary to test our new selection method., Published in MNRAS
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- 2019
23. The multiphase gas structure and kinematics in the circumnuclear region of NGC 5728
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Shimizu, Taro, Riffel, Rogério, Schnorr Müller, Allan, Storchi-Bergmann, Thaisa, and Veilleux, Sylvain
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Seyfert [Galaxies] ,active [Galaxies] ,nuclei [Galaxies] ,Cinemática ,Gases ,individual: NGC 5728 [Galaxies] ,Galaxias seyfert ,Nucleo galatico - Abstract
We report on our combined analysis of HST, VLT/MUSE, VLT/SINFONI, and ALMA observations of the local Seyfert 2 galaxy, NGC 5728 to investigate in detail the feeding and feedback of the active galactic nucleus (AGN). The data sets simultaneously probe the morphology, excitation, and kinematics of the stars, ionized gas, and molecular gas over a large range of spatial scales (10 pc to 10 kpc). NGC 5728 contains a large stellar bar that is driving gas along prominent dust lanes to the inner 1 kpc where the gas settles into a circumnuclear ring. The ring is strongly star forming and contains a substantial population of young stars as indicated by the lowered stellar velocity dispersion and gas excitation consistent with HII regions.We model the kinematics of the ring using the velocity field of the CO (2–1) emission and stars and find it is consistent with a rotating disc. The outer regions of the disc, where the dust lanes meet the ring, show signatures of inflow at a rate of 1 M yr−1. Inside the ring, we observe three molecular gas components corresponding to the circular rotation of the outer ring, a warped disc, and the nuclear stellar bar. The AGN is driving an ionized gas outflow that reaches a radius of 250 pc with a mass outflow rate of 0.08 M yr−1 consistent with its luminosity and scaling relations from previous studies.While we observe distinct holes in CO emission which could be signs of molecular gas removal, we find that largely the AGN is not disrupting the structure of the circumnuclear region.
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- 2019
24. A panchromatic spatially resolved study of the inner 500pc of NGC1052
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Hahn, Luis Gabriel Dahmer and Riffel, Rogério
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Galaxias elipticas ,Galáxia NGC 1052 ,Galaxias seyfert ,Nucleo galatico - Abstract
Com o objetivo de entender as limitações de modelos de população estelar no infravermelho próximo (NIR), realizamos na presente tese um teste extensivo de bibliotecas de modelos de populações estelares simples no NIR em comparação com o óptico. Tal estudo foi feito ajustando o espectro inteiro com o programa starlight e através da comparação de índices espectrais. Os principais resultados obtidos foram (i) bibliotecas de modelos NIR com baixa resolução espectral produzem resultados que dependem da escolha da biblioteca estelar e não produzem resultados consistentes entre si (ii) de maneira geral, bibliotecas no NIR com baixa resolucão espectral tendem a superestimar a extinção por poeira e a quantidade de população estelar jovem e (iii) para bibliotecas com alta resolução espectral, este cenário é consideravelmente melhor, com as duas bibliotecas testadas produzindo resultados mais compátíveis com os resultados encontrados no óptico. Com a metodologia consolidada, utilizamos cubos de dados no óptico e no NIR, ambos obtidos com o telescópio Gemini, para mapearmos a população estelar da galáxia elíptica NGC1052. A partir dos dados ópticos, a galáxia NGC1052 apresenta população estelar velha em todos os pontos do cubo de dados. No entanto, a partir de dados no NIR, os mesmos pontos apresentam uma contribuição de população estelar de idade intermediária. Afim de detectar populações sensíveis aos dois intervalos de comprimento de onda, combinamos os dois conjuntos de dados em um único cubo de dados, analisando assim simultaneamente o óptico e o NIR. Os resultados obtidos nesta análise pancromática mostram que a população estelar que domina a luz desta galáxia é predominantemente velha. Argumentamos que a divergência entre os resultados ópticos e NIR pode ser explicada pela baixa razão sinal-ruído da banda J e a ausência de dados na banda H, a qual contém grande parte das absorções estelares no NIR. Também mapeamos as propriedades do gás desta galáxia, encontrando 5 componentes cinemáticas nas linhas de emissão: (1 e 2) Duas componentes espacialmente não resolvidas, sendo uma componente larga em Hα, com um FWHM~de 3200kms-¹ e uma componente intermediária-larga no dubleto [Oiii] λλ4959,5007; (3) uma componente estendida de largura intermediária com 280
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- 2019
25. CHEERS results from NGC 3393 : III. Chandra x-ray spectroscopy of the narrow line region
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Maksym, W. Peter, Fabbiano, Giuseppina, Elvis, Martin, Karovska, Margarita, Paggi, Alessandro, Raymond, John Charles, Wang, Junfeng, Storchi-Bergmann, Thaisa, and Risaliti, Guido
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Seyfert [Galaxies] ,active [Galaxies] ,individual (NGC 3393) [Galaxies] ,jets [Galaxies] ,Galáxia NGC 3393 ,Galaxias seyfert ,Nucleo galatico ,galaxies [X-rays] - Abstract
We present spatially resolved Chandra narrow-band imaging and imaging spectroscopy of NGC 3393. This galaxy hosts a Compton-thick Seyfert 2 active galactic nucleus (AGN) with sub-kpc bipolar outflows that are strongly interacting with the circumnuclear gas. We identify narrow-band excess emission associated with the Ne IX 0.905 keV transition (with likely contributions due to intermediate-state iron emission) that points to strong shocks driven by AGN feedback. Imaging spectroscopy resolves outflow-interstellar medium (ISM) interaction sites and the surrounding ISM at ∼ 100 pc scales, and suggests the presence of a hot AGN wind above the plane at radii beyond the shock sites. The cross-cone shows evidence for reprocessing of photoionization that has passed through gaps in the torus, and also for collisionally excited plasma that may be powered by a shock-confined equatorial outflow. Deep X-ray observations at subarcsecond resolution (such as may be performed very efficiently by Lynx, which would also energetically resolve the complex line emission) are necessary to eliminate model degeneracies and reduce uncertainties in local feedback properties.
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- 2019
26. The first 62 AGN observed with SDSS-IV MaNGA – III : stellar and gas kinematics
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Ilha, Gabriele da Silva, Riffel, Rogemar André, Schimoia, Jáderson da Silva, Storchi-Bergmann, Thaisa, Rembold, Sandro Barboza, Riffel, Rogério, Wylezalek, Dominika, Shi, Yong, Costa, Luiz N. da, Machado, Alice Deconto, Law, David R., Bizyaev, D., Mallmann, Nícolas Dullius, Nascimento, Janaina Correa do, Maia, Marcio Antonio Geimba, and Cirolini, Rafael Fernando
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Galáxias ativas ,active [Galaxies] ,kinematics and dynamics [Galaxies] ,Cinemática ,general [Galaxies] ,Nucleo galatico - Abstract
We investigate the effects of active galactic nuclei (AGN) on the gas kinematics of their host galaxies, using MaNGA data for a sample of 62 AGN hosts and 109 control galaxies (inactive galaxies). We compare orientation of the line of nodes (kinematic position angle – PA) measured from the gas and stellar velocity fields for the two samples. We found that AGN hosts and control galaxies display similar kinematic PA offsets between gas and stars. However, we note that AGN have larger fractional velocity dispersion σ differences between gas and stars [σfrac = (σgas − σstars)/σstars] when compared to their controls, as obtained from the velocity dispersion values of the central (nuclear) pixel (2. 5 diameter). The AGN have a median value of σfrac of AGN = 0.04, while the median value for the control galaxies is CTR =−0.23. 75 per cent of the AGN show σfrac > −0.13, while 75 per cent of the normal galaxies show σfrac < −0.04, thus we suggest that the parameter σfrac can be used as an indicator of AGN activity. We find a correlation between the [OIII]λ5007 luminosity and σfrac for our sample. Our main conclusion is that the AGN already observed with MaNGA are not powerful enough to produce important outflows at galactic scales, but at 1–2 kpc scales, AGN feedback signatures are always present on their host galaxies.
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- 2019
27. Outflows in the inner kiloparsec of NGC1566 as revealed by molecular (ALMA) and ionized gas (Gemini-GMOS/IFU) kinematics
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Slater, Roy, Nagar, Neil M., Schnorr Müller, Allan, Storchi-Bergmann, Thaisa, Finlez, Carolina, Lena, Davide, Ramakrishnan, Venkatessh, Mundell, Carole G., Riffel, Rogemar André, Peterson, Bradley M., Robinson, Andrew, and Orellana, Gustavo
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Galáxias ativas ,Seyfert [Galaxies] ,active [Galaxies] ,kinematics and dynamics [Galaxies] ,nuclei [Galaxies] ,Cinemática ,Galaxias seyfert ,Nucleo galatico - Abstract
Context. Tracing nuclear inflows and outflows in active galactic nuclei (AGNs), determining the mass of gas involved in them, and their impact on the host galaxy and nuclear black hole requires 3D imaging studies of both the ionized and molecular gas. Aims. We map the distribution and kinematics of molecular and ionized gas in a sample of active galaxies to quantify the nuclear inflows and outflows. Here, we analyze the nuclear kinematics of NGC 1566 via ALMA observations of the CO J:2-1 emission at 24 pc spatial and ∼2.6 km s−1 spectral resolution, and Gemini-GMOS/IFU observations of ionized gas emission lines and stellar absorption lines at similar spatial resolution, and 123 km s−1 of intrinsic spectral resolution. Methods. The morphology and kinematics of stellar, molecular (CO), and ionized ([N II]) emission lines are compared to the expectations from rotation, outflows, and streaming inflows. Results. While both ionized and molecular gas show rotation signatures, there are significant non-circular motions in the innermost 200 pc and along spiral arms in the central kpc (CO). The nucleus shows a double-peaked CO profile (full width at zero intensity of 200 km s−1), and prominent (∼80 km s−1) blue- and redshifted lobes are found along the minor axis in the inner arcseconds. Perturbations by the large-scale bar can qualitatively explain all features in the observed velocity field. We thus favor the presence of a molecular outflow in the disk with true velocities of ∼180 km s−1 in the nucleus and decelerating to 0 by ∼72 pc. The implied molecular outflow rate is 5.6 M⊙ yr−1, with this gas accumulating in the nuclear 2″ arms. The ionized gas kinematics support an interpretation of a similar but more spherical outflow in the inner 100 pc, with no signs of deceleration. There is some evidence of streaming inflows of ∼50 km s−1 along specific spiral arms, and the estimated molecular mass inflow rate, ∼0.1 M⊙ yr−1, is significantly higher than the SMBH accretion rate (ṁ = 4.8 × 10−5 M⊙ yr−1).
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- 2019
28. The first 62 AGN observed with SDSS-IV MaNGA – IV. Gas excitation and star formation rate distributions
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Rogério Riffel, Sandro Barboza Rembold, Luiz N. da Costa, Marcio A. G. Maia, J. S. Schimoia, Thaisa Storchi-Bergmann, Rogemar A. Riffel, Gabriele da Silva Ilha, Nícolas Dullius Mallmann, Alice Deconto Machado, and Janaina Correa do Nascimento
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Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Flux ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Lambda ,Gas ionizado ,01 natural sciences ,Ionization ,0103 physical sciences ,Formacao de estrelas ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Effective radius ,010308 nuclear & particles physics ,Star formation ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Galáxias ativas ,Stars ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,Astrophysics::Earth and Planetary Astrophysics ,Nucleo galatico - Abstract
We present maps of the ionized gas flux distributions, excitation, star formation rate (SFR), surface mass density ΣH+, and obtain total values of SFR and ionized gas masses M for 62 active galactic nuclei (AGN) observed with SDSS-IV MaNGA and compare them with those of a control sample of 112 non-active galaxies. The most luminous AGN – with $L(\rm {[O\,{\small III}]}\lambda 5007) \ge 3.8\times 10^{40}\, \mbox{erg}\, \mbox{s}^{-1}$, and those hosted by earlier type galaxies are dominated by Seyfert excitation within 0.2 effective radius Re from the nucleus, surrounded by LINER excitation or transition regions, while the less luminous and hosted by later-type galaxies show equally frequent LINER and Seyfert excitation within $0.2\, R_\mathrm{ e}$. The extent R of the region ionized by the AGN follows the relation $R\propto \, L(\rm {[O\,{\small III}]})^{0.5}$ – as in the case of the broad-line region. The SFR distribution over the region ionized by hot stars is similar for AGN and controls, while the integrated SFR – in the range 10−3–10 M⊙ yr−1 is also similar for the late-type subsample, but higher in the AGN for 75 per cent of the early-type subsample. We thus conclude that there is no signature of AGN quenching star formation in the body of the galaxy in our sample. We also find that 66 per cent of the AGN have higher ionized gas masses M than the controls – in the range 105–3 × 107 M⊙ – while 75 per cent of the AGN have higher ΣH+ within $0.2\, R_\mathrm{ e}$ than the control galaxies.
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- 2019
29. A SINFONI view of the nuclear activity and circumnuclear star formation in NGC4303-II. Spatially resolved stellar populations
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Dametto, Natacha Zanon, Riffel, Rogério, Colina, Luis, Riffel, Rogemar André, Piqueras López, Javier, Davies, Richard I., Burtscher, Leonard, Menezes, Roberto Bertoldo, Arribas, Santiago, Pastoriza, Miriani Griselda, Labiano, Alvaro, Storchi-Bergmann, Thaisa, Hahn, Luis Gabriel Dahmer, and Sales, Dinalva Aires de
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Espectroscopia infravermelha ,Galáxia NGC 4303 ,Formacao de estrelas ,Nucleo galatico - Abstract
We present a spatially resolved stellar population study of the inner∼200 pc radius ofNGC 4303 based on near-infrared integral field spectroscopy with SINFONI/VLT at a spatial resolution of 40–80 pc and using the STARLIGHT code. We found that the distribution of thestellar populations presents a spatial variation, suggesting an age stratification. Three main structures stand out. Two nuclear blobs, one composed by young stars (t≤50 Myr) and onewith intermediate-age stars (50 Myr2 Gyr) is distributed outside the two blob structures.For the nuclear region (inner∼60 pc radius) we derived an SFR of 0.43 M yr−1and foundno signatures of non-thermal featureless continuum and hot dust emission, supporting thescenario in which an LLAGN/LINER-like source is hidden in the centre of NGC 4303. Thus, our results reveal a rather complex star formation history in NGC 4303, with different stellar population components coexisting with a low efficiency accreting black hole in its centre.
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- 2019
30. Precessing winds from the nucleus of the prototype Red Geyser?
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Riffel, Rogemar André, Nemmen, Rodrigo S., Ilha, Gabriele da Silva, Rembold, Sandro Barboza, Roy, Namrata, Storchi-Bergmann, Thaisa, Riffel, Rogério, Bundy, Kevin, Machado, Alice Deconto, Mallmann, Nícolas Dullius, Schimoia, Jáderson da Silva, Costa, Luiz N. da, and Maia, Marcio Antonio Geimba
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Galáxias ativas ,active [Galaxies] ,ISM [Galaxies] ,Meio interestelar ,Formacao de estrelas ,Galaxies nuclei ,star formation [Galaxies] ,Nucleo galatico - Abstract
Supermassive black holes (SMBHs) are present at the centre of most galaxies, with the related mass accretion processes giving origin to outflows in active galactic nuclei (AGNs). It has been presumed that only intense winds from luminous AGNs were able to suppress star formation until the discovery of a new class of galaxies with no recent star formation and with the nucleus in a quiescent state showing kpc scale outflows. We used SDSS MaNGA and Gemini Integral Field Spectroscopy of the prototype Red Geyser Akira and found that the orientation of the outflow changes by about 50° from its nucleus to kpc scales. A possible interpretation is that the outflow is produced by a precessing accretion disc due to a misalignment between the orientation of the disc and the spin of the SMBH. The precession of the central source is also supported by a similar change in the orientation of the ionization pattern. Although similar behaviour has commonly being reported for collimated relativistic jets, the precession of an AGN wide wind is reported here for the first time, implying on a larger work surface of the wind, which in turn increases the star formation suppression efficiency of the outflow.
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- 2019
31. Quantifying Feedback from Narrow Line Region Outflows in Nearby Active Galaxies. II. Spatially Resolved Mass Outflow Rates for the QSO2 Markarian 34
- Author
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D. Dashtamirova, J. Schmidt, Martin Elvis, Giuseppina Fabbiano, W. P. Maksym, S. B. Kraemer, Poshak Gandhi, Mitchell Revalski, Henrique R. Schmitt, Travis C. Fischer, Thaisa Storchi-Bergmann, C. L. Gnilka, and D. M. Crenshaw
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Active galactic nucleus ,active [Galaxies] ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Photoionization ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Kinetic energy ,individual (Mrk 34) [Galaxies] ,01 natural sciences ,Spectral line ,Luminosity ,0103 physical sciences ,Cinemática ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Line (formation) ,Physics ,010308 nuclear & particles physics ,kinematics and dynamics [Galaxies] ,jets and outflows [ISM] ,seyfert [Galaxies] ,Astronomy and Astrophysics ,Quasar ,Astrophysics - Astrophysics of Galaxies ,Galáxias ativas ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Outflow ,Nucleo galatico - Abstract
We present spatially resolved mass outflow rate measurements ($\dot M_{out}$) for the narrow line region of Markarian 34, the nearest Compton-thick type 2 quasar (QSO2). Spectra obtained with the Hubble Space Telescope and at Apache Point Observatory reveal complex kinematics, with distinct signatures of outflow and rotation within 2 kpc of the nucleus. Using multi-component photoionization models, we find that the outflow contains a total ionized gas mass of $M \approx 1.6 \times 10^6 M_{\odot}$. Combining this with the kinematics yields a peak outflow rate of $\dot M_{out} \approx 2.0 \pm 0.4~M_{\odot}$ yr$^{-1}$ at a distance of 470 pc from the nucleus, with a spatially integrated kinetic energy of $E \approx 1.4 \times 10^{55}$ erg. These outflows are more energetic than those observed in Mrk 573 and NGC 4151, supporting a correlation between luminosity and outflow strength even though they have similar peak outflow rates. The mix of rotational and outflowing components suggests that spatially resolved observations are required to determine accurate outflow parameters in systems with complex kinematics. (See appended erratum for updated values.), Accepted for Publication in ApJ on September 22, 2018. The paper has 23 pages and 13 figures. Version three appends an erratum published as Revalski et al. 2019, ApJ, 881, 167
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- 2018
32. LLAMA : nuclear stellar properties of Swift-BAT AGN and matched inactive galaxies
- Author
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Lin, Ming-Yi, Riffel, Rogério, Schnorr Müller, Allan, Storchi-Bergmann, Thaisa, and Veilleux, Sylvain
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Galáxias ativas ,spiral [Galaxies] ,Fotometria astronômica ,kinematics and dynamics [Galaxies] ,Cinemática ,photometry – galaxies: Seyfert [Galaxies] ,Galaxias seyfert ,Nucleo galatico - Abstract
In a complete sample of local 14–195 keV selected active galactic nuclei (AGNs) and inactive galaxies, matched by their host galaxy properties, we study the spatially resolved stellar kinematics and luminosity distributions at near-infrared wavelengths on scales of 10–150 pc, using SINFONI on the VLT. In this paper, we present the first half of the sample, which comprises 13 galaxies, eight AGNs and five inactive galaxies. The stellar velocity fields show a disc-like rotating pattern, for which the kinematic position angle is in agreement with the photometric position angle obtained from large scale images. For this set of galaxies, the stellar surface brightness of the inactive galaxy sample is generally comparable to the matched sample of AGN, but extends to lower surface brightness. After removal of the bulge contribution, we find a nuclear stellar light excess with an extended nuclear disc structure, which exhibits a size-luminosity relation. While we expect the excess luminosity to be associated with a dynamically cooler young stellar population, we do not typically see a matching drop in dispersion. This may be because these galaxies have pseudo-bulges in which the intrinsic dispersion increases towards the centre. And although the young stars may have an impact in the observed kinematics, their fraction is too small to dominate over the bulge and compensate the increase in dispersion at small radii, so no dispersion drop is seen. Finally, we find no evidence for a difference in the stellar kinematics and nuclear stellar luminosity excess between these active and inactive galaxies.
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- 2018
33. Morphology of AGN emission-line regions in SDSS-IV MaNGA survey
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He, Zhicheng, Sun, Ai-Lei, Zakamska, Nadia L., Wylezalek, Dominika, Kelly, Michael, Greene, Jenny E., Rembold, Sandro Barboza, Riffel, Rogério, and Riffel, Rogemar André
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Galáxias ativas ,Mapeamentos astronômicos ,Galaxies general ,Galaxies Seyfert ,Galaxies active ,Galaxies structure ,Nucleo galatico - Abstract
Extended narrow-line regions (NLRs) around active galactic nuclei (AGN) are shaped by the distribution of gas in the host galaxy and by the geometry of the circumnuclear obscuration, and thus they can be used to test the AGN unification model. In this work, we quantify the morphologies of the NLRs in 308 nearby AGN (z = 0 − 0.14, Lbol∼1042.4 − 44.1 erg s−1) from the MaNGA survey. Based on the NLR maps, we find that a large fraction (81 per cent) of these AGN have bi-conical NLR morphology. The distribution of their measured opening angles suggests that the intrinsic opening angles of the ionization cones have a mean value of 85◦–98◦ with a finite spread of 39◦–44◦ (1σ). Our inferred opening angle distribution implies a number ratio of type I to type II AGN of 1:1.6–2.3, consistent with other measurements of the type I/type II ratio at low AGN luminosities. Combining these measurements with the WISE photometry data, we find that redder mid-IR colour (lower effective temperature of dust) corresponds to stronger and narrower photoionized bicones. This relation is in agreement with the unification model that suggests that the bi-conical NLRs are shaped by a toroidal dusty structure within a few pc from the AGN. Furthermore, we find a significant alignment between theminor axis of host galaxy discs andAGNionization cones. Together, these findings suggest that obscuration on both circumnuclear (∼pc) and galactic (∼ kpc) scales is important in shaping and orienting the AGN NLRs.
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- 2018
34. LLAMA : normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies
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Rosario, David, Riffel, Rogério, Schnorr Müller, Allan, Storchi-Bergmann, Thaisa, and Veilleux, Sylvain
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Galáxias ativas ,statistical [Methods] ,Seyfert [Galaxies] ,Fotometria astronômica ,galaxies [Infrared] ,ISM [Galaxies] ,Formacao de estrelas ,star formation [Galaxies] ,Galaxias seyfert ,Nucleo galatico ,molecules [ISM] - Abstract
Using new Atacama Pathfinder Experiment and James Clerk Maxwell Telescope spectroscopy of the CO 2→1 line, we undertake a controlled study of cold molecular gas in moderately luminous (Lbol = 1043–44.5 erg s−1) active galactic nuclei (AGN) and inactive galaxies from the Luminous Local AGN with Matched Analogs (LLAMA) survey.We use spatially resolved infrared photometry of the LLAMA galaxies from 2MASS, the Wide-field Infrared Survey Explorer the Infrared Astronomical Satellite and the Herschel Space Observatory (Herschel), corrected for nuclear emission using multicomponent spectral energy distribution fits, to examine the dust-reprocessed star formation rates, molecular gas fractions and star formation efficiencies (SFEs) over their central 1–3 kpc. We find that the gas fractions and central SFEs of both active and inactive galaxies are similar when controlling for host stellar mass and morphology (Hubble type). The equivalent central molecular gas depletion times are consistent with the discs of normal spiral galaxies in the local Universe. Despite energetic arguments that the AGN in LLAMA should be capable of disrupting the observable cold molecular gas in their central environments, our results indicate that nuclear radiation only couples weakly with this phase. We find a mild preference for obscured AGN to contain higher amounts of central molecular gas, which suggests connection between AGN obscuration and the gaseous environment of the nucleus. Systems with depressed SFEs are not found among the LLAMA AGN. We speculate that the processes that sustain the collapse of molecular gas into dense pre-stellar cores may also be a prerequisite for the inflow of material on to AGN accretion discs.
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- 2018
35. Estudo das populações estelares em galáxias ativas no infravermelho próximo: o caso de NGC 4303
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Dametto, Natacha Zanon and Riffel, Rogério
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Galáxias ativas ,Galáxia NGC 4303 ,Populacoes estelares ,Galaxias Starburst ,Nucleo galatico - Abstract
Com o objetivo de estudar a relação entre a formação estelar circumnuclear e o nucleo ativo de galaxias, apresentamos aqui um estudo detalhado de uma galaxia prototipo: NG4303. Assim, apresentamos o estudo das populações estelares na região central (r . 200 pc) dessa fonte, atrav es de espectroscopia de campo integral no infravermelho pr oximo ( 1.1-2.4 m). Os dados foram obtidos com o instrumento SINFONI, anexado ao telesc opio VLT e apresentam resolução espacial de 40-80 pc. A metodologia do trabalho consiste em realizar sintese de população estelar utilizando o codigo starlight e novas gerações de modelos de populações estelares. Como primeira parte do trabalho, testamos a confiabilidade dos modelos no intervalo espectral do infravermelho proximo. Depois disso, aplicamos a metodologia a NGC4303, no intuito de estudar o historico de formação estelar espacialmente resolvido nessa fonte. Encontramos que a distribuiçao das populações estelares apresenta uma variação espacial, sugerindo uma estratificaçao em idade. Tres principais estruturas se destacam: Dois blobs, um composto por estrelas jovens (t 50 106anos) e outro composto por estrelas de idade intermediaria (50 106anos < t 2 109anos), ambos deslocados do centro. A terceira e uma estrutura do tipo bra co-espiral interno com estrelas de idade intermediaria, circundando o blob de estrelas jovens. Nossos resultados indicam que a formação estelar ocorreu atrraves de m ultiplos surtos de formação estelar nessa fonte. Alem do mais, as populaçoes estelares mais jovens (t . 2 Gyr) estão distribu das ao longo de um anel de formação estelar circumnuclear, com raio de r 250 pc. O anel apresenta taxas de formação estelar (SFRs) no intervalo de 0.002-0.14M ano1, favorecendo o cenario de formação estelar chamado `pearls-on-a-string'. A componente velha da população estelar (t > 2 109anos), a qual atribu mos a população estelar do bojo, esta distribuída fora dos dois blobs de idades mais jovens. Para a região nuclear (r 60 pc internos), derivamos um SFR de 0.43M ano1 e não encontramos nenhuma assinatura de continuo não-termico ou emissão de poeira quente, dando suporte ao cenario no qual um AGN de baixa luminosidade/LINER esta obscurecido no centro de NGC4303. Assim, nossos resultados revelam um cenario complexo de historico de formação estelar em NGC4303, com diferentes componentes da população estelar coexistindo com um buraco negro de baixa e ciência de acreção no seu centro. Aimed at studying the relation between circumnuclear star-formation and the active galactic nuclei, we present here a detailed study of a prototype object: NG4303. We present a stellar population study of the inner 200 pc radius of this source using near-infrared ( 1.1-2.4 m) integral eld spectroscopy with the VLT instrument SINFONI at a spatial resolution of 40-80 pc. Our methodology consists of performing stellar population synthesis using the starlight code and new generations of stellar population models. As the rst part of this thesis, we tested the reliability of the stellar population models in the near-infrared, after that, we applied our methodology to NGC4303 in order to study spatially the star formation history of this source. We found the distribution of the stellar populations presents a spatial variation, suggesting an age strati cation. Three main structures stand out. Two nuclear blobs, one composed by young stars (t 50 Myr) and one with intermediateage stars (50 Myr < t 2 Gyr) both shifted from the centre. The third one is an internal intermediate-age spiral arm-like structure, surrounding the blob of young stars. Our results indicate star formation has occurred through multiple bursts in this source. Furthermore, the younger stellar populations (t . 2 Gyr) are distributed along a circumnuclear star-forming ring with r 250 pc. The ring displays star formation rates (SFRs) in the range of 0.002-0.14M yr1, favoring the `pearls-on-astring' scenario. The old underlying bulge stellar population component (t > 2 Gyr) is distributed outside the two blob structures. For the nuclear region (inner 60 pc radius) we derived a SFR of 0.43M yr1 and found no signatures of non-thermal featureless continuum and hot dust emission, supporting the scenario in which a LLAGN/LINER-like source is hidden in the centre of NGC4303. Thus, our results reveal a rather complex star formation history in NGC4303, with di erent stellar population components coexisting with a low e ciency accreting black hole in its centre.
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- 2018
36. Bipolar ionization cones in the extended narrow-line region of nearby QSO2s
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Storchi-Bergmann, Thaisa, Oliveira, Bruno Dall'Agnol de, Micchi, L. F. Longo, Schmitt, Henrique Roberto, Fischer, Travis C., Kraemer, S. B., Crenshaw, Daniel Michael, Maksym, W. Peter, Elvis, Martin, Fabbiano, Giuseppina, and Colina, Luis
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Galáxias ativas ,Buracos negros ,emission lines [Quasars] ,active [Galaxies] ,jets and outflows [ISM] ,seyfert [Galaxies] ,jets [Galaxies] ,Gas ionizado ,Nucleo galatico ,supermassive black holes [Quasars] - Abstract
We have used narrowband [O III] λλ4959, 5007 and Hα+[N II] λλ6548, 84 Hubble Space Telescope (HST) images of nine luminous (L[O III]>1042 erg s−1) type 2 QSOs with redshifts 0.1
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- 2018
37. Gemini NIFS survey of feeding and feedback processes in nearby active galaxies : II. The sample and surface mass density profilesthe hidden monster and its outflow
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Riffel, Rogemar André, Storchi-Bergmann, Thaisa, Riffel, Rogério, Davies, Richard I., Bianchin, Marina, Diniz, Marlon Rodrigo, Schönell Júnior, Astor João, Burtscher, Leonard, Crenshaw, Daniel Michael, Fischer, Travis C., Hahn, Luis Gabriel Dahmer, Dametto, Natacha Zanon, and Rosario, David
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Mapeamentos astronômicos ,Espectroscopia infravermelha ,active [Galaxies] ,galaxies [Infrared] ,nuclei [Galaxies] ,Cinemática ,Galaxias seyfert ,Nucleo galatico - Abstract
We present and characterize a sample of 20 nearby Seyfert galaxies selected for having BAT 14–195 keV luminosities LX ≥ 1041.5 erg s−1, redshift z ≤ 0.015, being accessible for observations with the Gemini Near-Infrared Field Spectrograph (NIFS) and showing extended [O III]λ5007 emission. Our goal is to study Active Galactic Nucleus (AGN) feeding and feedback processes from near-infrared integral-field spectra, which include both ionized (H II) and hot molecular (H2) emission. This sample is complemented by other nine Seyfert galaxies previously observed with NIFS.We show that the host galaxy properties (absolute magnitudes MB, MH, central stellar velocity dispersion and axial ratio) show a similar distribution to those of the 69 BAT AGN. For the 20 galaxies already observed, we present surface mass density ( ) profiles for HII and H2 in their inner ∼500 pc, showing that HII emission presents a steeper radial gradient thanH2. This can be attributed to the different excitationmechanisms: ionization by AGN radiation for HII and heating by X-rays for H2. The mean surface mass densities are in the range (0.2 ≤ HII ≤ 35.9)M pc−2, and (0.2 ≤ H2 ≤ 13.9)× 10−3M pc−2, while the ratios between the HII and H2 masses range between ∼200 and 8000. The sample presented here will be used in future papers to map AGN gas excitation and kinematics, providing a census of the mass inflow and outflow rates and power as well as their relation with the AGN luminosity.
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- 2018
38. Outflows in the narrow-line region of bright Seyfert galaxies : I. GMOS-IFU data
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Santos, Izabel Cristina Freitas dos, Riffel, Rogemar André, Storchi-Bergmann, Thaisa, Elvis, Martin, Robinson, Andrew, Crenshaw, Daniel Michael, Nagar, Neil M., Lena, Davide, Schmitt, Henrique Roberto, and Kraemer, S. B.
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Seyfert [Galaxies] ,active [Galaxies] ,kinematics and dynamics [Galaxies] ,ISM [Galaxies] ,Cinemática ,individual: (Mrk 6, Mrk 79, Mrk 348, Mrk 607, Mrk 1058) [Galaxies] ,Galaxias seyfert ,Nucleo galatico - Abstract
We present two-dimensional maps of emission-line fluxes and kinematics, as well as of the stellar kinematics of the central few kpc of five bright nearby Seyfert galaxies –Mrk 6, Mrk 79, Mrk 348, Mrk 607, and Mrk 1058 – obtained from observations with the Gemini Multi-Object Spectrograph Integral Field Unit on the Gemini North Telescope. The data cover the inner 3.5 arcsec×5.0 arcsec – corresponding to physical scales in the range 0.6×0.9–1.5×2.2 kpc2 – at a spatial resolution ranging from 110 to 280 pc with a spectral coverage of 4300–7100Å and velocity resolution of ≈90 km s−1. The gas excitation is Seyfert like everywhere but show excitation gradients that are correlated with the gas kinematics, reddening and/or the gas density. The gas kinematics show in all cases two components: a rotation one similar to that observed in the stellar velocity field, and an outflow component. In the case of Mrk607, the gas is counter-rotating relative to the stars. Enhanced gas velocity dispersion is observed in association with the outflows according to two patterns: at the locations of the highest outflow velocities along the ionization axis or perpendicularly to it in a strip centred at the nucleus that we attribute to an equatorial outflow. Bipolar outflows are observed in Mrk 348 and Mrk 79, while in Mrk 1058 only the blueshifted part is clearly observed, while in cases of Mrk 6 and Mrk 607, the geometry of the outflow needs further constraints from modelling to be presented in a forthcoming study, where the mass flow rate and powers will also be obtained.
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- 2018
39. Hubble Space Telescope observations of extended [OIII]λ5007 emission in nearby QSO2s : new constraints on AGN host galaxy interaction
- Author
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Fischer, Travis C., Kraemer, S. B., Schmitt, Henrique Roberto, Micchi, L. F. Longo, Crenshaw, Daniel Michael, Revalski, Mitchell, Vestergaard, Marianne, Elvis, Martin, Gaskell, C.M., Hamann, Fred, Ho, Luis C., Hutchings, John B., Mushotzky, Richard, Netzer, Hagai, Storchi-Bergmann, Thaisa, Straughn, Amber N., Turner, T.J., and Ward, Martin John
- Subjects
Galáxias ativas ,Active ,Emission lines ,Cinemática ,Kinematics and dynamics ,Galaxies ,Quasars ,Nucleo galatico - Abstract
We present a Hubble Space Telescope survey of extended [O III] λ5007 emission for a sample of 12 nearby (z < 0.12), luminous Type 2 quasars (QSO2s), which we use to measure the extent and kinematics of their AGNionized gas. We find that the size of the observed [O III] regions scale with luminosity in comparison to nearby, less luminous Seyfert galaxies and radially outflowing kinematics to exist in all targets. We report an average maximum outflow radius of ∼600 pc, with gas continuing to be kinematically influenced by the central active galactic nucleus (AGN) out to an average radius of ∼1130 pc. These findings question the effectiveness of AGNs being capable of clearing material from their host bulge in the nearby universe and suggest that disruption of gas by AGN activity may prevent star formation without requiring evacuation. Additionally, we find a dichotomy in our targets when comparing [O III] radial extent and nuclear FWHM, where QSO2s with compact [O III] morphologies typically possess broader nuclear emission lines.
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- 2018
40. Circumnuclear star formation in Mrk 42 mapped with Gemini Near-infrared Integral Field Spectrograph
- Author
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Hennig, Moiré Gonçalves, Riffel, Rogemar André, Dors Júnior, Oli Luiz, Riffel, Rogério, Storchi-Bergmann, Thaisa, and Colina, Luis
- Subjects
Mapeamentos astronômicos ,Espectroscopia infravermelha ,active [Galaxies] ,galaxies [Infrared] ,ISM [Galaxies] ,Galaxias Starburst ,Cinemática ,individual: (Mrk 42) [Galaxies] ,Nucleo galatico - Abstract
We present Gemini Near-infrared Integral Field Spectrograph (NIFS) observations of the inner 1.5 × 1.5 kpc2 of the narrow-line Seyfert 1 galaxy Mrk 42 at a spatial resolution of 60 pc and spectral resolution of 40 kms−1. The emission-line flux and equivalent width maps clearly show a ring of circumnuclear star formation regions surrounding the nucleus with radius of ∼500 pc. The spectra of some of these regions show molecular absorption features which are probably of CN, TiO, or VO, indicating the presence of massive evolved stars in the thermally pulsing asymptotic giant branch phase. The gas kinematics of the ring is dominated by rotation in the plane of the galaxy, following the large-scale disc geometry, while at the nucleus an additional outflowing component is detected blueshifted by 300–500 km s−1, relative to the systemic velocity of the galaxy. Based on the equivalent width of Br γ we find pieces of evidence of gradients in the age of HII regions along the ring of Mrk 42, favouring the pearls on a string scenario of star formation. The broad component of Pa β emission line presents a FullWidth at Half Maximum of ∼1480 km s−1, implying in a mass of ∼2.5 × 106 M for the central supermassive black hole. Based on emission-line ratios we conclude that besides the active galactic nucleus, Mrk 42 presents nuclear Starburst activity.
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- 2018
41. The first 62 AGN observed with SDSS-IV MaNGA : II. resolved stellar populations
- Author
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Mallmann, Nícolas Dullius, Riffel, Rogério, Storchi-Bergmann, Thaisa, Rembold, Sandro Barboza, Riffel, Rogemar André, Schimoia, Jáderson da Silva, Costa, Luiz N. da, Avila-Reese, Vladimir, Sánchez, Sebastián F., Machado, Alice Deconto, Cirolini, Rafael Fernando, Ilha, Gabriele da Silva, and Nascimento, Janaina Correa do
- Subjects
Galáxias ativas ,Populacoes estelares ,Galaxies active ,Galaxies star formation ,Galaxies stellar content ,Formacao de estrelas ,Nucleo galatico - Abstract
We present spatially resolved stellar population (SP) age maps, average radial profiles and gradients for the first 62 active galactic nuclei (AGN) observed with Sloan Digital Sky Survey (SDSS)-IV Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) to study the effects of the active nuclei on the star formation history of the host galaxies. These results, derived using the STARLIGHT code, are compared with a control sample of non-active galaxies matching the properties of the AGN hosts. We find that the fraction of young SPs in highluminosity AGN is higher in the inner (R ≤ 0.5 Re) regions when compared with the control sample; low-luminosity AGN, on the other hand, present very similar fractions of young stars to the control sample hosts for the entire studied range (1 Re). The fraction of intermediate-age SP of the AGN hosts increases outwards, with a clear enhancement when compared with the control sample. The inner region of the galaxies (AGN and control galaxies) presents a dominant old SP, whose fraction decreases outwards.We also compare our results (differences between AGN and control galaxies) for the early- and late-type hosts and find no significant differences. In summary, our results suggest that the most luminous AGN seems to have been triggered by a recent supply of gas that has also triggered recent star formation (t ≤40 Myr) in the central region.
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- 2018
42. Dusty spirals versus gas kinematics in the inner kiloparsec of Four Low-Luminosity Active Galactic Nuclei
- Author
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Rogemar A. Riffel, Allan Schnorr Müller, Carine Brum, Thaisa Storchi-Bergmann, Davide Lena, and Andrew Robinson
- Subjects
individual (NGC 4501) [Galaxies] ,Seyfert [Galaxies] ,Active galactic nucleus ,Astronomy ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Gas ionizado ,Disc galaxy ,Lambda ,01 natural sciences ,Hubble sequence ,symbols.namesake ,0103 physical sciences ,Cinemática ,Disc ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Mapeamentos astronômicos ,Physics ,Luminous infrared galaxy ,kinematics and dynamics [Galaxies] ,010308 nuclear & particles physics ,individual (NGC 4450) [Galaxies] ,Astronomy and Astrophysics ,Espectros estelares ,Astrophysics - Astrophysics of Galaxies ,Galaxias seyfert ,Galaxy ,individual (NGC 2787) [Galaxies] ,individual (NGC 3982) [Galaxies] ,Supernova ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,symbols ,Nucleo galatico - Abstract
We used the Gemini Multi-Object Spectrograph Integral Field Unit to map the gas distribution, excitation and kinematics within the inner kiloparsec of four nearby low-luminosity active galaxies: NGC3982, NGC4501, NGC2787 and NGC4450. The observations cover the spectral range 5600-7000{\AA} at a velocity resolution of 120km/s and spatial resolution ranging from 50 to 70pc at the galaxies. Extended emission in H{\alpha}, [NII]{\lambda}{\lambda}6548,6583, [SII]{\lambda}{\lambda}6716,6730 over most of the field-of-view is observed for all galaxies, while only NGC3982 shows [OI]{\lambda}6300 extended emission. The H{\alpha} equivalent widths combined with the [NII]/H{\alpha} line ratios reveal that NGC3982 and NGC4450 harbor Seyfert nuclei surrounded by regions with LINER excitation, while NGC2787 and NGC4501 harbor LINER nuclei. NGC3982 shows a partial ring of recent star-formation at 500pc from the nucleus, while in NGC4501 a region at 500pc west of the nucleus shows LINER excitation but has been interpreted as an aging HII region with the gas excitation dominated by shocks from supernovae. The line-of-sight velocity field of the gas shows a rotation pattern for all galaxies, with deviations from pure disk rotation observed in NGC3982, NGC4501 and NGC4450. For NGC4501 and NGC4450, many of these deviations are spatially coincident with dust structures seen in optical continuum images, leading to the interpretation that the deviations are due to shocks in the gas traced by the dust. A speculation is that these shocks lead to loss of angular momentum, allowing the gas to be transferred inwards to feed the AGN. In the case of NGC2787, instead of deviations in the rotation field, we see a misalignment of 40{^\circ} between the orientation of the line of nodes of the gas rotation and the photometric major axis of the galaxy. Evidence of compact nuclear outflows are seen in NGC4501 and NGC4450., Comment: 20 pages, accepted for publication in MNRAS
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- 2017
43. OMEGA - OSIRIS Mapping of Emission-line Galaxies in A901/2: III. - Galaxy Properties Across Projected Phase Space in A901/2
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Meghan E. Gray, Bruno Rodríguez del Pino, Alfonso Aragón-Salamanca, R. Cool, Ana L. Chies-Santos, Asmus Böhm, Tim Weinzirl, Steven P. Bamford, and Christian Wolf
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FOS: Physical sciences ,clusters: individual: A901/2 [Galaxies] ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Metalicidade ,Galaxy merger ,star formation [Galaxies] ,01 natural sciences ,Peculiar galaxy ,Galaxy group ,0103 physical sciences ,distances and redshifts [Galaxies] ,Astrophysics::Solar and Stellar Astrophysics ,Deslocamento para o vermelho ,Brightest cluster galaxy ,010303 astronomy & astrophysics ,Lenticular galaxy ,Galaxy cluster ,Astrophysics::Galaxy Astrophysics ,Mapeamentos astronômicos ,Luminous infrared galaxy ,Physics ,010308 nuclear & particles physics ,Astronomy ,interferometers [Instrumentation] ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Elliptical galaxy ,Astrophysics::Earth and Planetary Astrophysics ,Nucleo galatico - Abstract
We conduct a comprehensive projected phase-space analysis of the A901/2 multi-cluster system at $z\sim0.165$. Aggregating redshifts from spectroscopy, tunable-filter imaging, and prism techniques, we assemble a sample of 856 cluster galaxies reaching $10^{8.5}M_\odot$ in stellar mass. We look for variations in cluster galaxy properties between virialised and non-virialised regions of projected phase-space (PPS). Our main conclusions point to relatively gentle environmental effects, expressed mainly on galaxy gas reservoirs. (1) Stacking the four subclusters in A901/2, we find galaxies in the virialised region are more massive, redder, and have marginally higher S��rsic indices, but their half-light radii and Hubble types are not significantly different. (2) After accounting for trends in stellar mass, there is a remaining change in rest-frame colour across PPS. Primarily, the colour difference is due to an absence in the virialised region of galaxies with rest-frame $B-V10^{9.85}M_\odot$) stellar mass. (3) There is an infalling population of lower-mass ($M_\star\leq10^{9.85}M_\odot$), relatively blue ($B-V, Accepted for publication in MNRAS
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- 2017
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44. Gemini near infrared field spectrograph observations of the Seyfert 2 galaxy Mrk 573 : in situ acceleration of ionized and molecular gas off fueling
- Author
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Fischer, Travis C., Machuca, Camilo, Diniz, Marlon Rodrigo, Crenshaw, Daniel Michael, Kraemer, S. B., Riffel, Rogemar André, Schmitt, Henrique Roberto, Baron, Fabien A., Storchi-Bergmann, Thaisa, Straughn, Amber N., Revalski, Mitchell, and Pope, Crystal L.
- Subjects
Espectroscopia infravermelha ,Seyfert [Galaxies] ,active [Galaxies] ,kinematics and dynamics [Galaxies] ,Espectros astronômicos ,Galaxias seyfert ,Nucleo galatico ,individual (Mrk 573) [Galaxies] - Abstract
We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in a ∼700×2100pc2 circumnuclear region of Mrk573, we find that kinematics within the Narrow- Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out to several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.
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- 2017
45. Feeding versus feedback in active galactic nuclei from near-infrared integral field spectroscopy : XII. NGC 5548
- Author
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Schönell Júnior, Astor João, Storchi-Bergmann, Thaisa, Riffel, Rogemar André, and Riffel, Rogério
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Galáxias ativas ,Galáxia NGC 5548 ,Seyfert [Galaxies] ,Populacoes estelares ,active [Galaxies] ,kinematics and dynamics – [Galaxies] ,nuclei – [Galaxies] ,Cinemática ,individual: NGC 5548 [Galaxies] ,Nucleo galatico ,Galaxias seyfert - Abstract
We map the gas excitation and kinematics, and the stellar population properties of the Seyfert 1 galaxy NGC 5548 using Gemini Near Infrared Integral Field Spectrograph in the J and K bands at a spatial and velocity resolution of 105 pc and 45 km s−1, respectively. Emission-line flux distributions in ionized and molecular gas extend up to ≈400 pc from the nucleus, where they are found to peak. The mass of HII is 4.8±0.6 × 106 M and the mass of warm H2 is 1.1±0.2 × 103 M , while the mass of cold H2 is estimated as 5.8±1.2 × 108 M . The Pa β emission shows two kinematic components: one in blueshift, with velocity reaching ≈−300 km s−1 and another showing a velocity field characteristic of rotation in the galaxy plane. The blueshifted component is also observed in the coronal line [S IX]λ1.2523 μm, while the rotational component is also observed in the molecular gas.We interpret this velocity field as due to gas rotating in the galaxy plane plus an outflow, and estimate a mass outflow rate of 6.8±0.75 M yr−1. Spectral synthesis of the continuum shows nuclear emission dominated by a featureless AGN continuum combined with hot dust emission attributed to a dusty torus. The stellar population is dominated by an old (2 Gyr < t ≤ 15 Gyr) component between 160 and 300 pc, while closer to the nucleus, an intermediate age (50 Myr < t ≤ 2 Gyr) component contributes at levels ranging from ≈40 per cent to ≈100 per cent to the flux at 2.12 μm.
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- 2017
46. Gas rotation, shocks and outflow within the inner 3 kpc of the radio galaxy 3C 33
- Author
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Allan Schnorr-Müller, Thaisa Storchi-Bergmann, and Guilherme S. Couto
- Subjects
Electron density ,active [Galaxies] ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Kinetic energy ,Gas ionizado ,01 natural sciences ,0103 physical sciences ,Cinemática ,Emission spectrum ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Spiral galaxy ,010308 nuclear & particles physics ,kinematics and dynamics [Galaxies] ,individual: 3C 33 [Galaxies] ,Velocity dispersion ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galáxias ativas ,Amplitude ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,nuclei [Galaxies] ,jets [Galaxies] ,Nucleo galatico - Abstract
We present optical integral field spectroscopy $-$ obtained with the Gemini Multi-Object Spectrograph $-$ of the inner $4.0 \times 5.8$ kpc$^2$ of the narrow line radio galaxy 3C 33 at a spatial resolution of 0.58 kpc. The gas emission shows three brightest structures: a strong knot of nuclear emission and two other knots at $\approx 1.4$ kpc south-west and north-east of the nucleus along the ionization axis. We detect two kinematic components in the emission lines profiles, with a "broader component" (with velocity dispersion $\sigma > 150$ km s$^{-1}$) being dominant within a $\sim$ 1 kpc wide strip ("the nuclear strip") running from the south-east to the north-west, perpendicular to the radio jet, and a narrower component ($\sigma < 100$ km s$^{-1}$) dominating elsewhere. Centroid velocity maps reveal a rotation pattern with velocity amplitudes reaching $\sim \pm 350$ km s$^{-1}$ in the region dominated by the narrow component, while residual blueshifts and redshifts relative to rotation are observed in the nuclear strip, where we also observe the highest values of the [N II]/H{\alpha}, [S II]/H{\alpha} and [O I]/H{\alpha} line ratios, and an increase of the gas temperature ($\sim 18000$ K), velocity dispersion and electron density ($\sim 500$ cm$^{-3}$). We interpret these residuals and increased line ratios as due to a lateral expansion of the ambient gas in the nuclear strip due to shocks produced by the passage of the radio jet. The effect of this expansion in the surrounding medium is very small, as its estimated kinetic power represents only $2.6 - 3.0 \times 10^{-5}$ of the AGN bolometric luminosity. A possible signature of inflow is revealed by an increase in the [O I]/H{\alpha} ratio values and velocity dispersions in the shape of two spiral arms extending to 2.3 kpc north-east and south-west from the nucleus., Comment: 16 pages, 14 figures, accepted by MNRAS
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- 2017
47. The complex, dusty narrow-line region of NGC 4388 : gas–jet interactions, outflows and extinction revealed by near-IR spectroscopy
- Author
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Rodrigues-Ardila, Alberto, Mason, Rachel E., Martins, Lucimara Pires, Ramos Almeida, Cristina, Riffel, Rogemar André, Riffel, Rogério, Lira, Paulina, Gonzalez Martin, Omaira, Dametto, Natacha Zanon, Flohic, Helene, Ho, Luis C., Dutra, Daniel Ruschel, Thanjavur, Karun, Colina, Luis, McDermid, Richard, Perlman, Eric, and Winge, Claudia
- Subjects
Espectroscopia infravermelha ,Seyfert – infrared ,Cinemática ,Individual ,Galaxies ,NGC 4388 – galaxies ,Jets – galaxies ,Galaxias seyfert ,Nucleo galatico ,Nuclei – galaxies ,Galáxia NGC 4388 - Abstract
We present Gemini/GNIRS (Gemini Near-Infrared Spectrograph) spectroscopy of the Seyfert 2 galaxy NGC 4388, with simultaneous coverage from 0.85 to 2.5 μm. Several spatially extended emission lines are detected for the first time, both in the obscured and unobscured portion of the optical narrow-line region (NLR), allowing us to assess the combined effects of the central continuum source, outflowing gas and shocks generated by the radio jet on the central 280 pc gas. The HI and [Fe II] lines allow us to map the extinction affecting the NLR. We found that the nuclear region is heavily obscured, with E(B − V) ∼ 1.9 mag. To the NE of the nucleus and up to ∼150 pc, the extinction remains large, ∼1 mag or larger, consistent with the system of dust lanes seen in optical imaging.We derived position–velocity diagrams for the most prominent lines as well as for the stellar component. Only the molecular gas and the stellar component display a well-organized pattern consistent with disc rotation. Other emission lines are kinematically perturbed or show little evidence of rotation. Extended high-ionization emission of sulphur, silicon and calcium is observed to distances of at least 200 pc both NE and SW of the nucleus. We compared flux ratios between these lines with photoionization models and conclude that radiation from the central source alone cannot explain the observed high-ionization spectrum. Shocks between the radio jet and the ambient gas are very likely an additional source of excitation. We conclude that NGC 4388 is a prime laboratory to study the interplay between all these mechanisms.
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- 2017
48. Gas inflows towards the nucleus of the Seyfert 2 galaxy NGC 1667
- Author
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Schnorr Müller, Allan, Storchi-Bergmann, Thaisa, Ferrari, Fabricio, and Nagar, Neil M.
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Seyfert [Galaxies] ,active [Galaxies] ,individual: (NGC 1667) [Galaxies] ,kinematics and dynamics [Galaxies] ,Galáxia NGC 1667 ,nuclei [Galaxies] ,Cinemática ,Galaxias seyfert ,Nucleo galatico - Abstract
We use optical spectra from the inner 2 × 3 kpc2 of the Seyfert 2 galaxy NGC 1667, obtained with the Gemini Multi-Object Spectrograph integral field spectrograph on the Gemini South telescope at a spatial resolution of ≈240 pc, to assess the feeding and feedback processes in this nearby active galactic nucleus (AGN). We have identified two gaseous kinematical components in the emission line profiles: a broader component (σ ≈ 400 km s−1) that is observed in the inner 1–2 arcsec and a narrower component (σ ≈ 200 km s−1) that is present over the entire field of view.We identify the broader component as due to an unresolved nuclear outflow. The narrower component velocity field shows strong isovelocity twists relative to a rotation pattern, implying the presence of strong non-circular motions. The subtraction of a rotational model reveals that these twists are caused by outflowing gas in the inner ≈1 arcsec, and by inflows associated with two spiral arms at larger radii.We calculate an ionized gas mass outflow rate of ˙Mout ≈ 0.16 M yr−1. We calculate the net gas mass flow rate across a series of concentric rings, obtaining a maximum mass inflow rate in ionized gas of ≈2.8 M yr−1 at 800 pc from the nucleus, which is two orders of magnitude larger than the accretion rate necessary to power this AGN. However, as the mass inflow rate decreases at smaller radii, most of the gas probably will not reach the AGN, but accumulate in the inner few hundred parsecs. This will create a reservoir of gas that can trigger the formation of new stars.
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- 2017
49. The first 62 AGNs observed with SDSS-IV MaNGA : I. Their characterization and definition of a control sample
- Author
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Rembold, Sandro Barboza, Schimoia, Jáderson da Silva, Storchi-Bergmann, Thaisa, Riffel, Rogério, Riffel, Rogemar André, Mallmann, Nícolas Dullius, Nascimento, Janaina Correa do, Moreira, Thales Nunes, Ilha, Gabriele da Silva, Machado, Alice Deconto, Cirolini, Rafael Fernando, Costa, Luiz N. da, Maia, Marcio Antonio Geimba, Santiago, Basilio Xavier, Schneider, D.P., Wylezalek, Dominika, Bizyaev, D., Pan, K., and Muller-Sanchez, Francisco
- Subjects
Galáxias ativas ,Populacoes estelares ,active [Galaxies] ,stellar content [Galaxies] ,Formacao de estrelas ,Nucleo galatico - Abstract
We report the characterization of the first 62 Mapping Nearby Galaxies at the Apache Point Observatory active galactic nuclei (AGNs) hosts and the definition of a control sample of non-active galaxies. This control sample was selected in order to match the AGN hosts in terms of stellar mass, redshift, visual morphology and inclination. The stellar masses are in the range 9.4 < log M/M < 11.5, and most objects have redshifts ≤0.08. The AGN sample is mostly comprised low-luminosity AGN, with only 17 ‘strong AGN’ with L([O III]λ5007 Å) ≥ 3.8 × 1040 erg s−1. The inner 1–3 kpc of the control sample galaxies are dominated by the oldest (≥ 4Gyr) component, with a small contribution of intermediate age and young stars (
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- 2017
50. Investigando a natureza LINER da galáxia elíptica NGC 5044
- Author
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Diniz, Suzi Izaquiel Ferreira, Pastoriza, Miriani Griselda, and Riffel, Rogério
- Subjects
Galaxias elipticas ,Galáxia NGC 5044 ,Galaxias seyfert ,Nucleo galatico - Abstract
No presente trabalho zemos uso do espectr ografo multi-objeto do Gemini (GMOS) no modo de unidade de campo integral para mapear a popula c~ao estelar, a distribui c~ao do uxo das linhas de emiss~ao e a cinem atica do g as no kpc mais interno da gal axia NGC 5044. A partir da s ntese de popula c~ao estelar encontramos que a emiss~ao do cont nuo e dominada por estrelas velhas de alta metalicidade (13 Gyr, 2,5 Z ). Tamb em encontramos que a emiss~ao nuclear dessa gal axia e dilu da por uma emiss~ao n~ao t ermica, a qual atribu mos a presen ca de um n ucleo ativo gal actico (AGN) fraco. Al em disso, registramos pela primeira vez uma componente alargada (FWHM 3000 kms1) na emiss~ao da linha de H na regi~ao nuclear de NGC 5044. Por meio de diagramas de diagn ostico de raz~oes de linhas de emiss~ao encontramos que coexistem dois processos de ioniza c~ao dominantes, enquanto a regi~ao nuclear (200 pc mais internos) e ionizada por um AGN de baixa luminosidade, as estruturas lamentares s~ao consistentes com excita c~ao por choques. O campo de velocidade de H mostra evid^encias de um disco em rota c~ao, o qual tem uma amplitude de velocidade de 240 km s1a 136 pc do n ucleo. Assumindo uma aproxima c~ao Kepleriana estimamos que a massa dentro desse raio e 1; 9 0; 9 109M , o qual est a de acordo com o valor obtido utilizando a rela c~ao M- , MSMBH=1,8 1; 6 109M . Modelando o campo de velocidade do g as ionizado por uma componente de disco em rota c~ao mais in ows em dire c~ao ao n ucleo ao longo das estruturas lamentares, obtivemos uma taxa de massa de in ow de 0,4 M . Essa taxa de in ow e su ciente para acionar o AGN central na NGC 5044. We used Gemini Multi-Object Spectrograph (GMOS) in the Integral Field Unit mode to map the stellar population, emission line ux distributions and gas kinematics in the inner kpc of NGC 5044. From the stellar populations synthesis we found that the continuum emission is dominated by old high metallicity stars (13 Gyr, 2.5 Z ). Also, its nuclear emission is diluted by a non thermal emission, which we attribute to the presence of a weak active galactic nuclei (AGN). In addition, we report for the rst time a broad component (FWHM 3000 km s1) in the H emission line in the nuclear region of NGC 5044. By using emission line ratio diagnostic diagrams we found that two dominant ionization processes coexist, while the nuclear region (inner 200 pc) is ionized by a low luminosity AGN, being the lamentary structures consistent with excited by shocks. The H velocity eld shows evidence of a rotating disk, which has a velocity amplitude of 240 km s1at 136 pc from the nucleus. Assuming a Keplerian approach we estimated that the mass inside this radius is 1:9 0:9 109M , which is in agreement with the value obtained through the M- relation, MSMBH=1.8 1:6 109M . Modelling the ionized gas velocity eld by a rotating disk component plus in ows towards the nucleus along lamentary structures, we obtain a mass in ow rate of 0.4 M . This in ow rate is enough to power the central AGN in NGC 5044.
- Published
- 2017
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