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Related papers: TPHO: a time-dependent photoionisation model for A…

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Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods. Optical reverberation mapping allowed us to constrain the spatial dimension of the…

High Energy Astrophysical Phenomena · Physics 2017-12-05 P. A. Rojas Lobos , R. W. Goosmann , F. Marin , D. Savić

Atomic data and plasma models play a crucial role in the diagnosis and interpretation of astrophysical spectra, thus influencing our understanding of the universe. In this investigation we present a systematic comparison of the leading…

High Energy Astrophysical Phenomena · Physics 2016-12-07 M. Mehdipour , J. S. Kaastra , T. Kallman

We consider energy budgets and radiative history of 8 fading AGN, identified from mismatch between the ionizion of very extended (>10 kpc) ionized clouds and the luminosity of the nucleus viewed directly. All show significant fading on…

The winds of ionized gas driven by Active Galactic Nuclei (AGN) can be studied through absorption lines in their X-ray spectra. A recurring feature of these outflows is their broad ionization distribution, including essentially all…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Jonathan Stern , Ehud Behar , Ari Laor , Alexei Baskin , Tomer Holczer

To explain the properties of the local galaxy population, theoretical models require active galactic nuclei (AGN) to inject energy into host galaxies, thereby expelling outflows of gas that would otherwise form stars. Observational tests of…

Negative feedback from active galactic nuclei (AGN) is considered a key mechanism in shaping galaxy evolution. Fast, extended outflows are frequently detected in the AGN host galaxies at all redshifts and luminosities, both in ionised and…

Proximity zone fossils (PZFs) are ionization signatures around recently active galactic nuclei (AGN) where metal species in the circumgalactic medium remain over-ionized after the AGN has shut-off due to their long recombination timescales.…

Astrophysics of Galaxies · Physics 2018-04-13 Benjamin D. Oppenheimer , Marijke Segers , Joop Schaye , Alexander J. Richings , Robert A. Crain

We present spatially resolved kinematic measurements of AGN-driven outflows in dwarf galaxies in the stellar mass range $\sim6\times10^8 - 9\times10^9 M_\odot$, selected from SDSS DR7,8 and followed up with Keck/LRIS spectroscopy. We find…

Astrophysics of Galaxies · Physics 2019-10-16 Christina Manzano-King , Gabriela Canalizo , Laura V. Sales

Energetic ionized gas outflows driven by active galactic nuclei (AGN) have been studied as a key phenomenon related to AGN feedback. To probe the kinematics of the gas in the narrow line region, [O III] ${\lambda}$5007 has been utilized in…

Astrophysics of Galaxies · Physics 2017-08-22 Daeun Kang , Jong-Hak Woo , Hyun-Jin Bae

We have studied the thermal instabilities in the context of Active Galactic Nuclei (AGN), addressing the cases of thin and thick (stratified) X-ray illuminated media. For that, we have compared the behaviour of different models in pressure…

Astrophysics · Physics 2007-05-23 A. C. Goncalves , S. Collin , A. -M. Dumont

We provide a new approach to measure power spectra and reconstruct time series in active galactic nuclei (AGNs) based on the fact that the Fourier transform of AGN stochastic variations is a series of complex Gaussian random variables. The…

Instrumentation and Methods for Astrophysics · Physics 2018-03-14 Yan-Rong Li , Jian-Min Wang

[Abridged] Enormous observational efforts have been made to constrain the energetics of AGN feedback by mapping the kinematics of the ionized gas on kpc scale. We study how the observed kinematics and inferred energetics are affected by…

Astrophysics of Galaxies · Physics 2016-10-12 B. Husemann , J. Scharwächter , V. N. Bennert , V. Mainieri , J. -H. Woo , D. Kakkad

Spectroscopic observations of quasar outflows at rest-frame 500-1000 Angstrom have immense diagnostic power. We present analyses of such data, where absorption troughs from three important ions are measured: first, O IV and O IV* that allow…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nahum Arav , Benoit Borguet , Carter Chamberlain , Doug Edmonds , Charles Danforth

Among the most extreme objects in the Universe, active galactic nuclei (AGN) are luminous centers of galaxies where a black hole feeds on surrounding matter. The variability patterns of the light emitted by an AGN contain information about…

Instrumentation and Methods for Astrophysics · Physics 2021-06-22 Ji Won Park , Ashley Villar , Yin Li , Yan-Fei Jiang , Shirley Ho , Joshua Yao-Yu Lin , Philip J. Marshall , Aaron Roodman

Spectral absorption features in active galactic nuclei (AGNs) have traditionally been attributed to outflowing photoionized gas located at a distance of order a parsec from the central continuum source. However, recent observations of QSO…

Astrophysics · Physics 2009-11-07 J. E. Everett , A. Konigl , N. Arav

The systematic analysis of optical large-scale surveys has revealed a population of dwarf galaxies hosting AGN, which have been confirmed by X-ray follow-up observations. Recently, the MaNGA survey identified six dwarf galaxies that appear…

Astrophysics of Galaxies · Physics 2019-01-09 Sophie Koudmani , Debora Sijacki , Martin A. Bourne , Matthew C. Smith

The effects of Active Galactic Nuclei (AGNs) on their host-galaxies depend on the coupling between the injected energy and the interstellar medium (ISM). Here, we model and quantify the impact of long-range AGN ionizing radiation -- in…

Astrophysics of Galaxies · Physics 2015-02-09 Orianne Roos , Stéphanie Juneau , Frédéric Bournaud , Jared M. Gabor

Although now routinely incorporated into hydrodynamic simulations of galaxy evolution, the true importance of the feedback effect of the outflows driven by active galactic nuclei (AGN) remains uncertain from an observational perspective.…

We present MEGARA (Multi-Espectr\'ografo en GTC de Alta Resoluci\'on para Astronom\'ia) Integral Field Unit (IFU) observations of 5 local type-2 quasars (QSO2s, z $\sim 0.1$) from the Quasar Feedback (QSOFEED) sample. These active galactic…

Establishing the role of active galactic nuclei (AGN) during the formation of galaxies remains one of the greatest challenges of galaxy formation theory. Towards addressing this, we summarise our recent work investigating: (1) the physical…

Astrophysics of Galaxies · Physics 2021-07-01 C. M. Harrison , S. J. Molyneux , J. Scholtz , M. E. Jarvis
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