scholarly journals JETS AND OUTFLOWS IN RADIO GALAXIES: IMPLICATIONS FOR AGN FEEDBACK

2012 ◽  
Vol 08 ◽  
pp. 396-399 ◽  
Author(s):  
ELEONORA TORRESI ◽  
PAOLA GRANDI ◽  
ELISA COSTANTINI ◽  
GIORGIO G. C. PALUMBO
Keyword(s):  
Black Holes ◽  
Galaxy Formation ◽  
Surrounding Medium ◽  
Radio Galaxies ◽  
Broad Line ◽  
Jets And Outflows ◽  
Massive Black Holes ◽  
X Ray ◽  
Formation And Evolution

One of the main debated astrophysical problems is the role of the AGN feedback in galaxy formation. It is known that massive black holes have a profound effect on the formation and evolution of galaxies, but how black holes and galaxies communicate is still an unsolved problem. For Radio Galaxies, feedback studies have mainly focused on jet/cavity systems in the most massive and X–ray luminous galaxy clusters. The recent high–resolution detection of warm absorbers in some Broad Line Radio Galaxies allow us to investigate the interplay between the nuclear engine and the surrounding medium from a different perspective. We report on the detection of warm absorbers in two Broad Line Radio Galaxies, 3C 382 and 3C 390.3, and discuss the physical and energetic properties of the absorbing gas. Finally, we attempt a comparison between radio–loud and radio–quiet outflows.

scholarly journals JD8 - Hot Interstellar Matter in Elliptical Galaxies

2009 ◽  
Vol 5 (H15) ◽  
pp. 269-270
Author(s):  
Dong-Woo Kim ◽  
Silvia Pellegrini
Keyword(s):  
Black Holes ◽  
Star Formation ◽  
Analytical Modeling ◽  
Elliptical Galaxies ◽  
Theoretical Studies ◽  
Interstellar Matter ◽  
Significant Progress ◽  
Massive Black Holes ◽  
X Ray ◽  
Formation And Evolution

The physical properties of the hot interstellar matter in elliptical galaxies are directly related with the formation and evolution of elliptical galaxies via star formation episodes, environmental effects such as stripping, infall, and mergers, and growth of super-massive black holes. The recent successful Chandra and XMM-Newton X-ray space missions have provided a large amount of high spatial/spectral resolution observational data on the hot ISM in elliptical galaxies. At the same time, theoretical studies with numerical simulations and analytical modeling of the dynamical and chemical evolution of elliptical galaxies have made a significant progress and start to predict various observable quantities.

scholarly journals Comparison of SEDs of very massive radio-loud and radio-quiet AGN

2019 ◽  
Vol 492 (1) ◽  
pp. 315-325 ◽  
Author(s):  
Maitrayee Gupta ◽  
Marek Sikora ◽  
Katarzyna Rusinek
Keyword(s):  
Black Holes ◽  
Inclination Angle ◽  
Radio Galaxies ◽  
Polar Regions ◽  
Massive Black Holes ◽  
X Ray ◽  
Spectral Components ◽  
Radiative Output

ABSTRACT The main objective of this work is to establish and interpret the dominant spectral components and their differences in radio-loud (RL) and radio-quiet (RQ) AGN with very massive black holes, and accreting at moderate rates. Such a sample is selected from the Swift/BAT catalogue of AGN having determined optical spectra types and hosting black holes with masses $\rm \gt 10^{8.5}\, M_{\odot }$. We confirm our previous results, that radio loudness distribution of Swift/BAT AGN is bimodal and that radio galaxies are about two times X-ray louder than their RQ counterparts. We show that the average X-ray loudness (defined as a ratio of luminosity in the 14–195 keV band to that at 12 μm) of Type 1 and Type 2 AGN is very similar. This similarity holds for both RL and RQ subsamples and indicates negligible dependence of the observed X-ray luminosities on the inclination angle in both populations. In both the radiative output is dominated by mid-IR and hard X-ray components, and relatively weak UV luminosities indicate large amounts of dust in polar regions.

scholarly journals The role of black holes in galaxy formation and evolution

Nature ◽  
2009 ◽  
Vol 460 (7252) ◽  
pp. 213-219 ◽  
Author(s):  
A. Cattaneo ◽  
S. M. Faber ◽  
J. Binney ◽  
A. Dekel ◽  
J. Kormendy ◽  
...  
Keyword(s):  
Black Holes ◽  
Galaxy Formation ◽  
Galaxy Formation And Evolution ◽  
Formation And Evolution

scholarly journals Formation and early evolution of massive black holes

2006 ◽  
Vol 2 (S238) ◽  
pp. 73-82
Author(s):  
Piero Madau
Keyword(s):  
Black Holes ◽  
Dark Matter ◽  
Ionization State ◽  
First Stars ◽  
Massive Black Holes ◽  
X Ray ◽  
Hard Radiation ◽  
Low Mass ◽  
The Universe

AbstractThe astrophysical processes that led to the formation of the first seed black holes and to their growth into the supermassive variety that powers bright quasars at z ∼ 6 are poorly understood. In standard ΛCDM hierarchical cosmologies, the earliest massive holes (MBHs) likely formed at redshift z ≳ 15 at the centers of low-mass (M ≳ 5 × 105 M⊙) dark matter “minihalos”, and produced hard radiation by accretion. FUV/X-ray photons from such “miniquasars” may have permeated the universe more uniformly than EUV radiation, reduced gas clumping, and changed the chemistry of primordial gas. The role of accreting seed black holes in determining the thermal and ionization state of the intergalactic medium depends on the amount of cold and dense gas that forms and gets retained in protogalaxies after the formation of the first stars. The highest resolution N-body simulation to date of Galactic substructure shows that subhalos below the atomic cooling mass were very inefficient at forming stars.

scholarly journals X-ray properties of reverberation-mapped AGNs with super-Eddington accreting massive black holes

2019 ◽  
Vol 15 (S356) ◽  
pp. 143-143
Author(s):  
Jaya Maithil ◽  
Michael S. Brotherton ◽  
Bin Luo ◽  
Ohad Shemmer ◽  
Sarah C. Gallagher ◽  
...  
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Accretion Rate ◽  
Time Lags ◽  
Black Hole Mass ◽  
Host Galaxies ◽  
Massive Black Holes ◽  
X Ray ◽  
Photon Index ◽  
The Impact

AbstractActive Galactic Nuclei (AGN) exhibit multi-wavelength properties that are representative of the underlying physical processes taking place in the vicinity of the accreting supermassive black hole. The black hole mass and the accretion rate are fundamental for understanding the growth of black holes, their evolution, and the impact on the host galaxies. Recent results on reverberation-mapped AGNs show that the highest accretion rate objects have systematic shorter time-lags. These super-Eddington accreting massive black holes (SEAMBHs) show BLR size 3-8 times smaller than predicted by the Radius-Luminosity (R-L) relationship. Hence, the single-epoch virial black hole mass estimates of highly accreting AGNs have an overestimation of a factor of 3-8 times. SEAMBHs likely have a slim accretion disk rather than a thin disk that is diagnostic in X-ray. I will present the extreme X-ray properties of a sample of dozen of SEAMBHs. They indeed have a steep hard X-ray photon index, Γ, and demonstrate a steeper power-law slope, ασx.

scholarly journals The Role of Radio Loud Phase of Nuclear Activity in Galaxy Formation and Evolution

2013 ◽  
Vol 9 (S304) ◽  
pp. 419-420
Author(s):  
Gabriel A. Ohanian
Keyword(s):  
Galaxy Formation ◽  
Subsequent Development ◽  
Nuclear Activity ◽  
Evolution Of Galaxies ◽  
Galaxy Formation And Evolution ◽  
Formation And Evolution ◽  
Key Questions

AbstractKey questions, which arise when one tries to clear up a problem of formation and evolution of galaxies, is the question of energy: what is the energetic budget of AGN owing to form galaxies and provide its subsequent development? Hence, for understanding the formation and evolution of galaxies, it is important to estimate the energetic budget of AGN which we try to do involving radio loud phase of nuclear activity.

scholarly journals A universal 21 cm signature of growing massive black holes in the early Universe

2019 ◽  
Author(s):  
S Sazonov ◽  
I Khabibullin
Keyword(s):  
Black Holes ◽  
Early Universe ◽  
Generation X ◽  
Mass Range ◽  
Gravitational Potential Energy ◽  
Next Generation ◽  
Massive Black Holes ◽  
X Ray ◽  
Extreme Uv ◽  
Square Kilometer Array

Abstract There is a hope that looking into the early Universe with next-generation telescopes, one will be able to observe the early accretion growth of supermassive black holes (BHs) when their masses were ∼104–106M⊙. According to the standard accretion theory, the bulk of the gravitational potential energy released by radiatively efficient accretion of matter onto a BH in this mass range is expected to be emitted in the extreme UV–ultrasoft X-ray bands. We demonstrate that such a ’miniquasar’ at z ∼ 15 should leave a specific, localized imprint on the 21 cm cosmological signal. Namely, its position on the sky will be surrounded by a region with a fairly sharp boundary of several arcmin radius, within which the 21 cm brightness temperature quickly grows inwards from the background value of ∼−250 mK to ∼+30 mK. The size of this region is only weakly sensitive to the BH mass, so that the flux density of the excess 21 cm signal is expected to be ∼0.1–0.2 mJy at z ∼ 15 and should be detectable by the Square Kilometer Array. We argue that an optimal strategy would be to search for such signals from high-z miniquasar candidates that can be found and localized with a next-generation X-ray mission such as Lynx. A detection of the predicted 21 cm signal would provide a measurement of the growing BH’s redshift to within Δz/(1 + z) ≲ 0.01.

WEIGHING SUPER-MASSIVE BLACK HOLES WITH X-RAY–EMITTING GAS

2009 ◽  
Author(s):  
D. A. BUOTE ◽  
P. J. HUMPHREY ◽  
F. BRIGHENTI ◽  
K. GEBHARDT ◽  
W. G. MATHEWS
Keyword(s):  
Black Holes ◽  
Massive Black Holes ◽  
X Ray
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