The Galaxy Zoo survey for giant AGN-ionized clouds: past and present black hole accretion events

@article{Keel2011TheGZ,
  title={The Galaxy Zoo survey for giant AGN-ionized clouds: past and present black hole accretion events},
  author={William C. Keel and S. Drew Chojnowski and Vardha N. Bennert and Kevin Schawinski and Chris J. Lintott and Stuart Lynn and Anna Pancoast and Chelsea E. Harris and Anna M. Nierenberg and Alessandro Sonnenfeld and Richard A. Proctor Proctor},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2011},
  volume={420},
  pages={878-900}
}
Some active galactic nuclei (AGN) are surrounded by extended emission-line regions (EELRs), which trace both the illumination pattern of escaping radiation and its history over the light-travel time from the AGN to the gas. From a new set of such EELRs, we present evidence that the AGN in many Seyfert galaxies undergo luminous episodes 0.2–2×10 5 years in duration. Motivated by the discovery of the spectacular nebula known as Hanny’s Voorwerp, ionized by a powerful AGN which has apparently… 

An [O iii] search for extended emission around AGN with H i mapping: a distant cloud ionized by Mkn 1

Motivated by the discovery of large ionized clouds around AGN, and particularly the large fraction of those that are consistent with photoionized gaseous tidal debris, we searched for [O iii]

CO-EVOLUTION OF GALAXIES AND CENTRAL BLACK HOLES: OBSERVATIONAL EVIDENCE ON THE TRIGGER OF AGN FEEDBACK

A comprehensive analysis of the extended emission-line region (EELR) around quasars is presented. A new Subaru/Suprime-Cam observation is combined with a literature search, resulting in a compilation

HST IMAGING OF FADING AGN CANDIDATES. I. HOST-GALAXY PROPERTIES AND ORIGIN OF THE EXTENDED GAS

We present narrow- and medium-band Hubble Space Telescope imaging, with additional supporting ground-based imaging, spectrophotometry, and Fabry–Perot interferometric data, for eight galaxies

Detailed Accretion History of the Supermassive Black Hole in NGC 5972 over the Past ≳104 yr through the Extended Emission-line Region

We present integral field spectroscopic observations of NGC 5972 obtained with the Multi-Unit Spectroscopic Explorer at the Very Large Telescope. NGC 5972 is a nearby galaxy containing both an active

Sizes and Kinematics of Extended Narrow-line Regions in Luminous Obscured AGN Selected by Broadband Images

To study the impact of active galactic nuclei (AGN) feedback on their galactic ISM, we present Magellan long-slit spectroscopy of 12 luminous nearby obscured AGN ( , z ∼ 0.1). These objects are

Ionized Outflows in Nearby Quasars Are Poorly Coupled to Their Host Galaxies

We analyze Multi-Unit Spectroscopic Explorer observations of nine low-redshift (z < 0.1) Palomar-Green quasar host galaxies to investigate the spatial distribution and kinematics of the warm, ionized

Fading AGN Candidates: AGN Histories and Outflow Signatures

We consider the energy budgets and radiative history of eight fading active galactic nuclei (AGNs), identified from an energy shortfall between the requirements to ionize very extended (radius > 10

MUSE REVEALS A RECENT MERGER IN THE POST-STARBURST HOST GALAXY OF THE TDE ASASSN-14li

We present Multi Unit Spectroscopic Explorer (MUSE) integral field spectroscopic observations of the host galaxy (PGC 043234) of one of the closest (z = 0.0206, D ≃ 90 Mpc) and best-studied tidal

A TALE OF TWO NARROW-LINE REGIONS: IONIZATION, KINEMATICS, AND SPECTRAL ENERGY DISTRIBUTIONS FOR A LOCAL PAIR OF MERGING OBSCURED ACTIVE GALAXIES

We explore the gas ionization and kinematics, as well as the optical-IR spectral energy distributions for UGC 11185, a nearby pair of merging galaxies hosting obscured active galactic nuclei (AGNs),

The Physics of the Coronal-line Region for Galaxies in Mapping Galaxies at Apache Point Observatory

The fundamental nature and extent of the coronal-line region (CLR), which may serve as a vital tracer for active galactic nucleus (AGN) activity, remain unresolved. Previous studies suggest that the
...

References

SHOWING 1-10 OF 63 REFERENCES

Active Galactic Nuclei and Galaxy Interactions

We perform a statistical analysis of active galactic nucleus (AGN) host characteristics and nuclear activity for AGNs in pairs and without companions. Our study concerns a sample of AGNs derived from

The origin of gas in extended narrow-line regions of nearby Seyfert galaxies – I. NGC 7212

The extended narrow-line region (ENLR) of an active galactic nucleus (AGN) is a region of highly ionized gas with a size of a few up to 15–20 kpc. When it shows a conical or biconical shape with the

EXTENDED EMISSION-LINE REGIONS: REMNANTS OF QUASAR SUPERWINDS?

We give an overview of our recent integral-field-unit spectroscopy of luminous extended emission-line regions (EELRs) around low-redshift quasars, including new observations of five fields. Previous

Anisotropic ionizing radiation in NGC5252

THE different kinds of active galactic nuclei (AGNs) and quasars may be fundamentally similar, and owe their observed differences to anisotropy in the distribution of their emitted radiation:

Galaxy Zoo: 'Hanny's Voorwerp', a quasar light echo?

We report the discovery of an unusual object near the spiral galaxy IC 2497, discovered by visual inspection of the Sloan Digital Sky Survey (SDSS) as part of the Galaxy Zoo project. The object,

GALAXY ZOO: THE FUNDAMENTALLY DIFFERENT CO-EVOLUTION OF SUPERMASSIVE BLACK HOLES AND THEIR EARLY- AND LATE-TYPE HOST GALAXIES

We use data from the Sloan Digital Sky Survey and visual classifications of morphology from the Galaxy Zoo project to study black hole growth in the nearby universe (z < 0.05) and to break down the

Discovery of a Very Extended Emission-Line Region around the Seyfert 2 Galaxy NGC 4388

We found a very large, ~35 kpc, emission-line region around the Seyfert type 2 galaxy NGC 4388, using deep narrowband imaging with the prime focus camera (Suprime-Cam) of the Subaru Telescope. This

Gemini/GMOS IFU gas velocity ‘tomography’ of the narrow line region of nearby active galaxies

We present two-dimensional (2D) mapping of the gas velocity field of the inner few hundred parsecs of six nearby active galaxies, using spectra obtained with the integral field unit of the Gemini

The host galaxies of active galactic nuclei

We examine the properties of the host galaxies of 22 623 narrow-line active galactic nuclei (AGN) with 0.02 < z < 0.3 selected from a complete sample of 122 808 galaxies from the Sloan Digital Sky
...