scholarly journals A survey of AGN and supermassive black holes in the COSMOS Survey

2006 ◽  
Vol 2 (S238) ◽  
pp. 287-290 ◽  
Author(s):  
Chris D. Impey ◽  
Jon R. Trump ◽  
Pat J. McCarthy ◽  
Martin Elvis ◽  
John P. Huchra ◽  
...  
Keyword(s):  
Black Holes ◽  
Large Scale ◽  
Supermassive Black Holes ◽  
Host Galaxy ◽  
Data Set ◽  
X Ray ◽  
Cosmic Evolution ◽  
Early Results ◽  
Multi Wavelength ◽  
History Of

AbstractThe Cosmic Evolution Survey (COSMOS) is an HST/ACS imaging survey of 2 square degrees centered on RA = 10:00:28.6, Dec = + 02:12:21 (J2000). While the primary goal of the survey is to study evolution of galaxy morphology and large scale structure, an extensive multi-wavelength data set allows for a sensitive survey of AGN. Spectroscopy of optical counterparts to faint X-ray and radio sources is being carried out with the Magallen (Baade) Telescope and the ESO VLT. By achieving ∼80 redshift completeness down to I AB = 3, the eventual yield of AGN will be ∼1100 over the whole field.Early results on supermassive black holes are described. The goals of the survey include a bolometric census of AGN down to moderate luminosities, the cosmic evolution and fueling history of the central engines, and a study of AGN environments on scales ranging from the host galaxy to clusters and superclusters.

scholarly journals What do observations tell us about the highest-redshift supermassive black holes?

2019 ◽  
Vol 15 (S356) ◽  
pp. 261-275
Author(s):  
Benny Trakhtenbrot
Keyword(s):  
Black Holes ◽  
Large Scale ◽  
Big Bang ◽  
Supermassive Black Holes ◽  
High Mass ◽  
Host Galaxy ◽  
Host Galaxies ◽  
Lower Mass ◽  
Wide Range ◽  
Multi Wavelength

AbstractI review the current understanding of some key properties of the earliest growing supermassive black holes (SMBHs), as determined from the most up-to-date observations of z ≲ 5 quasars. This includes their accretion rates and growth history, their host galaxies, and the large-scale environments that enabled their emergence less than a billion years after the Big Bang. The available multi-wavelength data show that these SMBHs are consistent with Eddington-limited, radiatively efficient accretion that had to proceed almost continuously since very early epochs. ALMA observations of the hosts’ ISM reveal gas-rich, well developed galaxies, with a wide range of SFRs that may exceed ∼1000 Mȯyr−1. Moreover, ALMA uncovers a high fraction of companion, interacting galaxies, separated by < 100 kpc (projected). This supports the idea that the first generation of high-mass, luminous SMBHs grew in over-dense environments, and that major mergers may be important drivers for rapid SMBH and host galaxy growth. Current X-ray surveys cannot access the lower-mass, supposedly more abundant counterparts of these rare z ≳ 5 massive quasars, which should be able to elucidate the earliest stages of BH formation and growth. Such lower-mass nuclear BHs will be the prime targets of the deepest surveys planned for the next generation of facilities, such as the upcoming Athena mission and the future Lynx mission concept.

scholarly journals The XXL Survey

2018 ◽  
Vol 620 ◽  
pp. A14 ◽  
Author(s):  
Vernesa Smolčić ◽  
Huib Intema ◽  
Bruno Šlaus ◽  
Somak Raychaudhury ◽  
Mladen Novak ◽  
...  
Keyword(s):  
Large Scale ◽  
Galactic Nuclei ◽  
Atmospheric Modeling ◽  
Radio Continuum ◽  
Large Field ◽  
Data Set ◽  
Cosmic Evolution ◽  
Multi Wavelength ◽  
Continuum Sensitivity ◽  
Combined Data

We present the 25 square-degree GMRT-XXL-N 610 MHz radio continuum survey, conducted at 50 cm wavelength with the Giant Metrewave Radio Telescope (GMRT) towards the XXL Northern field (XXL-N). We combined previously published observations of the XMM-Large Scale Structure (XMM-LSS) field, located in the central part of XXL-N, with newly conducted observations towards the remaining XXL-N area, and imaged the combined data-set using the Source Peeling and Atmospheric Modeling (SPAM) pipeline. The final mosaic encompasses a total area of 30.4 square degrees, with rms <150 μJy beam−1 over 60% of the area. The rms achieved in the inner 9.6 square degree area, enclosing the XMM-LSS field, is about 200 μJy beam−1, while that over the outer 12.66 square degree area (which excludes the noisy edges) is about 45 μJy beam−1. The resolution of the final mosaic is 6.5 arcsec. We present a catalogue of 5434 sources detected at ≥7 ×rms. We verify, and correct the reliability of, the catalog in terms of astrometry, flux, and false detection rate. Making use of the (to date) deepest radio continuum survey over a relatively large (2 square degree) field, complete at the flux levels probed by the GMRT-XXL-N survey, we also assess the survey’s incompleteness as a function of flux density. The radio continuum sensitivity reached over a large field with a wealth of multi-wavelength data available makes the GMRT-XXL-N 610 MHz survey an important asset for studying the physical properties, environments and cosmic evolution of radio sources, in particular radio-selected active galactic nuclei (AGN).

scholarly journals The fates of merging supermassive black holes and a proposal for a new class of X-ray sources

2020 ◽  
Vol 498 (3) ◽  
pp. 3807-3816
Author(s):  
Charles Zivancev ◽  
Jeremiah Ostriker ◽  
Andreas H W Küpper
Keyword(s):  
Black Holes ◽  
Structure Formation ◽  
Hierarchical Structure ◽  
Dynamical Evolution ◽  
Supermassive Black Holes ◽  
Host Galaxy ◽  
X Ray ◽  
Massive Galaxies ◽  
New Class ◽  
Low Mass

ABSTRACT We perform N-body simulations on some of the most massive galaxies extracted from a cosmological simulation of hierarchical structure formation with total masses in the range 1012 M⊙ &lt; Mtot &lt; 3 × 1013 M⊙ from 4 ≥ z ≥ 0. After galactic mergers, we track the dynamical evolution of the infalling black holes (BHs) around their host’s central BHs (CBHs). From 11 different simulations, we find that, of the 86 infalling BHs with masses &gt;104 M⊙, 36 merge with their host’s CBH, 13 are ejected from their host galaxy, and 37 are still orbiting at z = 0. Across all galaxies, 33 BHs are kicked to a higher orbit after close interactions with the CBH binary or multiple, after which only one of them merged with their hosts. These orbiting BHs should be detectable by their anomalous (not low-mass X-ray binary) spectra. The X-ray luminosities of the orbiting massive BHs at z = 0 are in the range $10^{28}-10^{43}\, \mathrm{erg}~\mathrm{s}^{-1}$, with a currently undetectable median value of $10^{33}\, \mathrm{erg}~\mathrm{s}^{-1}$. However, the most luminous ∼5 per cent should be detectable by existing X-ray facilities.

scholarly journals Studying the Evolving Universe with XMM-Newton and Chandra

2003 ◽  
Vol 214 ◽  
pp. 46-58 ◽  
Author(s):  
Günther Hasinger
Keyword(s):  
Black Holes ◽  
High Resolution ◽  
Absorption Line ◽  
Large Scale ◽  
Cosmic Time ◽  
Supermassive Black Holes ◽  
Redshift Distribution ◽  
X Ray ◽  
X Ray Background

Two X-ray observatories, the NASA observatory Chandra and the ESA mission XMM-Newton, provide powerful new diagnostics of the “hot universe”. In this article I review recent X–ray observations of the evolving universe. First indications of the warm/hot intergalactic medium, tracing out the large scale structure of the universe, have been obtained lately in sensitive Chandra and XMM-Newton high resolution absorption line spectroscopy of bright blazars. High resolution X–ray spectroscopy and imaging also provides important new constraints on the physical condition of the cooling matter in the centers of clusters, requiring major modifications to the standard cooling flow models. One possibility is, that the supermassive black hole in the giant central galaxies significantly energizes the gas in the cluster.XMM-Newton and Chandra low resolution spectroscopy detected significant Fe Kα absorption features in the spectrum of the ultraluminous, high redshift lensed broad absorption line QSO APM 08279+5255, yielding new insights in the outflow geometry and in particular indicate a supersolar Fe/O ratio. Chandra high resolution imaging spectroscopy of the nearby ultraluminous infrared galaxy and obscured QSO NGC 6240 for the first time gave evidence of two active supermassive black holes in the same galaxy, likely bound to coalesce in the course of the ongoing major merger in this galaxy.Deep X–ray surveys have shown that the cosmic X-ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80 % of the 0.1–10 keV X-ray background into discrete sources. Optical spectroscopic identifications show that the sources producing the bulk of the X-ray background are a mixture of obscured (type–1) and unobscured (type–2) AGNs, as predicted by the XRB population synthesis models. A class of highly luminous type–2 AGN, so called QSO-2s, has been detected in the deepest Chandra and XMM-Newton surveys. The new Chandra AGN redshift distribution peaks at much lower redshifts (z ≈ 0.7) than that based on ROSAT data, indicating that the evolution of Seyfert galaxies occurs at significantly later cosmic time than that of QSOs.

scholarly journals Tracing the accretion history of supermassive black holes through X-ray variability: results from the ChandraDeep Field-South

2017 ◽  
Vol 471 (4) ◽  
pp. 4398-4411 ◽  
Author(s):  
M. Paolillo ◽  
I. Papadakis ◽  
W. N. Brandt ◽  
B. Luo ◽  
Y. Q. Xue ◽  
...  
Keyword(s):  
Black Holes ◽  
Supermassive Black Holes ◽  
X Ray ◽  
History Of

scholarly journals The Cosmic History of Black Hole Growth from Deep Multiwavelength Surveys

2012 ◽  
Vol 2012 ◽  
pp. 1-21 ◽  
Author(s):  
Ezequiel Treister ◽  
C. Megan Urry
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Optical Emission ◽  
Supermassive Black Holes ◽  
X Ray ◽  
Open Questions ◽  
Black Hole Growth ◽  
History Of ◽  
Hole Growth ◽  
Cosmic History

Significant progress has been made in the last few years on understanding how supermassive black holes form and grow. In this paper, we begin by reviewing the spectral signatures of active galactic nuclei (AGN) ranging from radio to hard X-ray wavelengths. We then describe the most commonly used methods to find these sources, including optical/UV, radio, infrared, and X-ray emission, and optical emission lines. We then describe the main observational properties of the obscured and unobscured AGN population. Finally, we summarize the cosmic history of black hole accretion, that is, when in the history of the universe supermassive black holes were getting most of their mass. We finish with a summary of open questions and a description of planned and future observatories that are going to help answer them.

scholarly journals Molecular gas in the central region of NGC 7213

2020 ◽  
Vol 641 ◽  
pp. A151
Author(s):  
F. Salvestrini ◽  
C. Gruppioni ◽  
F. Pozzi ◽  
C. Vignali ◽  
A. Giannetti ◽  
...  
Keyword(s):  
Star Formation ◽  
Emission Line ◽  
Large Scale ◽  
Host Galaxy ◽  
Molecular Gas ◽  
X Ray ◽  
Gas Kinematics ◽  
Star Formation Activity ◽  
Multi Wavelength

We present a multi-wavelength study (from X-ray to mm) of the nearby low-luminosity active galactic nucleus NGC 7213. We combine the information from the different bands to characterise the source in terms of contribution from the AGN and the host-galaxy interstellar medium. This approach allows us to provide a coherent picture of the role of the AGN and its impact, if any, on the star formation and molecular gas properties of the host galaxy. We focused our study on archival ALMA Cycle 1 observations, where the CO(2–1) emission line has been used as a tracer of the molecular gas. Using the 3DBAROLO code on ALMA data, we performed the modelling of the molecular gas kinematics traced by the CO(2–1) emission, finding a rotationally dominated pattern. The molecular gas mass of the host galaxy was estimated from the integrated CO(2–1) emission line obtained with APEX data, assuming an αCO conversion factor. Had we used the ALMA data, we would have underestimated the gas masses by a factor ∼3, given the filtering out of the large-scale emission in interferometric observations. We also performed a complete X-ray spectral analysis on archival observations, revealing a relatively faint and unobscured AGN. The AGN proved to be too faint to significantly affect the properties of the host galaxy, such as star formation activity and molecular gas kinematics and distribution.

scholarly journals Can we infer the past activity of M31⋆ as we do for Sgr A⋆?

2016 ◽  
Vol 11 (S322) ◽  
pp. 253-256
Author(s):  
Maïca Clavel ◽  
Régis Terrier ◽  
Andrea Goldwurm ◽  
Mark R. Morris ◽  
Gabriele Ponti
Keyword(s):  
Black Holes ◽  
Molecular Clouds ◽  
Galactic Center ◽  
Supermassive Black Holes ◽  
X Ray ◽  
The Past ◽  
Upper Limits ◽  
History Of ◽  
Sgr A ◽  
Past Activity

AbstractThe history of supermassive black holes’ activity can be partly constrained by monitoring the diffuse X-ray emission possibly created by the echoes of past events propagating through the molecular clouds of their respective environments. In particular, using this method we have demonstrated that our Galaxy’s supermassive black hole, Sgr A⋆, has experienced multiple periods of higher activity in the last centuries, likely due to several short but very energetic events, and we now investigate the possibility of studying the past activity of other supermassive black holes by applying the same method to M31⋆. We set strong constraints on putative phase transitions of this more distant galactic nucleus but the existence of short events such as the ones observed in the Galactic center cannot be assessed with the upper limits we derived.

scholarly journals Cosmological Evolution of Supermassive Black Holes: Mass Functions and Spins

2012 ◽  
Vol 8 (S290) ◽  
pp. 259-260 ◽  
Author(s):  
Yan-Rong Li ◽  
Jian-Min Wang ◽  
Luis C. Ho
Keyword(s):  
Black Holes ◽  
Mass Function ◽  
Supermassive Black Holes ◽  
Cosmological Evolution ◽  
Radiative Efficiency ◽  
Bolometric Luminosity ◽  
History Of ◽  
Minor Mergers ◽  
Mass Dependent ◽  
Mass Functions

AbstractWe derive the mass function of supermassive black holes (SMBHs) over the redshift range 0 > z ≲ 2, using the latest deep luminosity and mass functions of field galaxies. Applying this mass function, combined with the bolometric luminosity function of active galactic nuclei (AGNs), into the the continuity equation of SMBH number density, we explicitly obtain the mass-dependent cosmological evolution of the radiative efficiency for accretion. We suggest that the accretion history of SMBHs and their spins evolve in two distinct regimes: an early phase of prolonged accretion, plausibly driven by major mergers, during which the black hole spins up, then switching to a period of random, episodic accretion, governed by minor mergers and internal secular processes, during which the hole spins down. The transition epoch depends on mass, mirroring other evidence for “cosmic downsizing” in the AGN population.

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