scholarly journals Quasar evolution: black hole mass and accretion rate determination

2006 ◽  
Vol 2 (S238) ◽  
pp. 83-86
Author(s):  
Deborah Dultzin-Hacyan ◽  
Paola Marziani ◽  
C. Alenka Negrete ◽  
Jack W. Sulentic
Keyword(s):  
Black Hole ◽  
Accretion Rate ◽  
Selection Effects ◽  
Black Hole Mass ◽  
Spectral Evolution ◽  
Spatially Resolved ◽  
Central Engine ◽  
Line Region ◽  
Ratio Determination ◽  
Almost All

AbstractAccurate measurements of emission line properties are crucial to understand the physics of the broad line region in quasars. This region consists of warm gas that is closest to the quasar central engine and has not been spatially resolved for almost all sources. We present here an analysis of optical and IR data for a large sample of quasars, covering the Hi Hβ spectral region in the redshift range 0 ≲ z ≲ 2.5. Spectra were interpreted within the framework of the the so-called “eigenvector 1” parameter space, which can be viewed as a tentative H-R diagram for quasars. We stress the lack of spectral evolution in the low ionization lines of quasars, with prominent Fe ii emission also at z ≳ 2. We also show how selection effects influence the ability to find quasars radiating at low Eddington ratio in flux-limited surveys. The quasar similarity at different redshift is probably due to the absence of super-Eddington radiators (at least within the caveats of black hole mass and Eddington ratio determination discussed in this paper) as well as to the limited Eddington ratio range within which quasars seem to radiate.

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 Probing within the bondi radius of the ultramassive black hole in NGC 1600

2021 ◽  
Author(s):  
J Runge ◽  
S A Walker
Keyword(s):  
Black Hole ◽  
Accretion Rate ◽  
Statistical Significance ◽  
Large Mass ◽  
Nearby Galaxy ◽  
Density Profiles ◽  
Spatially Resolved ◽  
Single Temperature ◽  
Slight Rise ◽  
Two Temperature

Abstract We present deep (250 ks) Chandra observations of the nearby galaxy group NGC 1600, which has at its centre an ultramassive black hole (17±1.5 billion M⊙). The exceptionally large mass of the black hole coupled with its low redshift makes it one of only a handful of black holes for which spatially resolved temperature and density profiles can be obtained within the Bondi radius with the high spatial resolution of Chandra. We analyzed the hot gas properties within the Bondi accretion radius R$_\rm {B}=1{_{.}^{\prime\prime}} 2 - 1{_{.}^{\prime\prime}} 7= 0.38 - 0.54~\rm {kpc}$. Within a ∼3 kpc radius, we find two temperature components with statistical significance. Both the single temperature and two temperature models show only a very slight rise in temperature towards the centre, and are consistent with being flat. This is in contrast with the expectation from Bondi accretion for a temperature profile which increases towards the centre, and appears to indicate that the dynamics of the gas are not being determined by the central black hole. The density profile follows a relatively shallow ρ∝ r−[0.61 ± 0.13] relationship within the Bondi radius, which suggests that the true accretion rate on to the black hole may be lower than the classical Bondi accretion rate.

scholarly journals Observations of the γ-ray emitting narrow-line Seyfert 1, SBS 0846+513, and its host galaxy

2021 ◽  
Author(s):  
Timothy S Hamilton ◽  
Marco Berton ◽  
Sonia Antón ◽  
Lorenzo Busoni ◽  
Alessandro Caccianiga ◽  
...  
Keyword(s):  
Black Hole ◽  
Adaptive Optics ◽  
Host Galaxy ◽  
Narrow Line ◽  
Black Hole Mass ◽  
Residual Structure ◽  
Line Region ◽  
Resolution Imaging ◽  
Γ Ray ◽  
Adaptive Optics System

Abstract The γ-ray emitting galaxy SBS 0846 + 513 has been classified as a Narrow-Line Seyfert 1 (NLS1) from its spectroscopy, and on that basis would be thought likely to have a small central black hole hosted in a spiral galaxy. But very few of the γ-ray NLS1 have high-resolution imaging of their hosts, so it is unknown how the morphology expectation holds up for the γ-emitting class. We have observed this galaxy in the J-band with the Large Binocular Telescope’s LUCI1 camera and the ARGOS adaptive optics system. We estimate its black hole mass to lie between $4.2\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 9.7\times 10^7$, using the correlation with bulge luminosity, or $1.9\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 2.4\times 10^7$ using the correlation with Sérsic index. Our favoured estimate is 4.2 × 107M⊙, putting its mass at the high end of the NLS1 range in general but consistent with others that are γ-ray emitters. These estimates are independent of the Broad Line Region viewing geometry and avoid any underestimates due to looking down the jet axis. Its host shows evidence of a bulge + disc structure, from the isophote shape and residual structure in the nuclear-subtracted image. This supports the idea that γ-ray NLS1 may be spiral galaxies, like their non-jetted counterparts.

scholarly journals Linking the central engine to the jet properties in radio loud AGN

2014 ◽  
Vol 10 (S313) ◽  
pp. 329-330
Author(s):  
A. Olguín-Iglesias ◽  
J. León-Tavares ◽  
V. Chavushyan ◽  
E. Valtaoja ◽  
C. Añorve ◽  
...  
Keyword(s):  
Black Hole ◽  
Host Galaxy ◽  
Base Line ◽  
Black Hole Mass ◽  
Host Galaxies ◽  
Optical Telescope ◽  
Central Engine ◽  
Early Results ◽  
Relativistic Jet ◽  
Line Array

AbstractWe explore the connection between the black hole mass and its relativistic jet for a sample of radio-loud AGN (z < 1), in which the relativistic jet parameters are well estimated by means of long term monitoring with the 14m Metsähovi millimeter wave telescope and the Very Long Base-line Array (VLBA). NIR host galaxy images taken with the NOTCam on the Nordic Optical Telescope (NOT) and retrieved from the 2MASS all-sky survey allowed us to perform a detailed surface brightness decomposition of the host galaxies in our sample and to estimate reliable black hole masses via their bulge luminosities. We present early results on the correlations between black hole mass and the relativistic jet parameters. Our preliminary results suggest that the more massive the black hole is, the faster and the more luminous jet it produces.

scholarly journals The correlations between optical variability and physical parameters of quasars in SDSS Stripe 82

2012 ◽  
Vol 8 (S290) ◽  
pp. 373-374
Author(s):  
Wenwen Zuo ◽  
Xue-Bing Wu ◽  
Yi-Qing Liu ◽  
Cheng-Liang Jiao
Keyword(s):  
Black Hole ◽  
Rest Frame ◽  
Accretion Rate ◽  
Physical Parameters ◽  
Optical Variability ◽  
Black Hole Mass ◽  
Disk Model ◽  
Bolometric Luminosity ◽  
Data Points ◽  
Quasar Variability

AbstractWe investigate the optical variability of 7658 quasars from SDSS Stripe 82. Taking advantage of a larger sample and relatively more data points for each quasar, we estimate variability amplitudes and divide the sample into small bins of redshift, rest-frame wavelength, black hole mass, Eddington ratio, and bolometric luminosity, respectively, to investigate the relationships between variability and these parameters. An anti-correlation between variability and rest-frame wavelength is found. The variability amplitude of radio-quiet quasars shows almost no cosmological evolution, but that of radio-loud ones may weakly anti-correlate with redshift. In addition, variability increases as either luminosity or Eddington ratio decreases. However, the relationship between variability and black hole mass is uncertain; it is negative when the influence of Eddington ratio is excluded, but positive when the influence of luminosity is excluded. The intrinsic distribution of variability amplitudes for radio-loud and radio-quiet quasars are different. Both radio-loud and radio-quiet quasars exhibit a bluer-when-brighter chromatism. Assuming that quasar variability is caused by variations of accretion rate, the Shakura–Sunyaev disk model can reproduce the tendencies of observed correlations between variability and rest-frame wavelength, luminosity as well as Eddington ratio, supporting that changes of accretion rate play an important role in producing the observed optical variability. However, the predicted positive correlation between variability and black hole mass seems to be inconsistent with the observed negative correlation between them in small bins of Eddington ratio, which suggests that other physical mechanisms may still need to be considered in modifying the simple accretion disk model.

scholarly journals Matter accretion onto a conformal gravity black hole

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
G. Abbas ◽  
A. Ditta
Keyword(s):  
Black Hole ◽  
Equations Of State ◽  
Accretion Rate ◽  
Black Hole Mass ◽  
Conformal Gravity ◽  
De Sitter ◽  
Schwarzschild Black Hole ◽  
Mass Rate ◽  
Mass Accretion Rate ◽  
The Impact

AbstractThe accretion of test fluids flowing onto a black hole is investigated. Particularly, by adopting a dynamical Hamiltonian approach, we are capable to find the critical points for various cases of black hole in conformal gravity. In these cases, we have analyzed the general solutions of accretion employing the isothermal equations of state. The steady state and spherically symmetric accretion of different test fluids onto the conformal gravity black hole has been considered. Further, we have classified these flows in the context of equations of state and the cases of conformal gravity black hole. The new behavior of polytropic fluid accretion is also discussed in all three cases of black hole. Black hole mass accretion rate is the most important part of this research in which we have investigated that the Schwarzschild black hole produce a typical signature than the conformal gravity black hole and Schwarzschild–de Sitter black hole. The critical fluid flow and the mass accretion rate have been presented graphically by the impact parameters $$\beta $$ β , $$\gamma $$ γ , k and these parameters have great significance. Additionally, the maximum mass rate of accretion fall near the universal and Killing horizons and minimum rate of accretion occurs in between these regions. Finally, the results are compared with the different cases of black hole available in the literature.

scholarly journals AGN orientation through the spectroscopic correlations and model of dusty cone shell

2021 ◽  
Author(s):  
M Lakićević ◽  
J Kovačević-Dojčinović ◽  
L Č Popović
Keyword(s):  
Black Hole ◽  
Spectral Properties ◽  
Alternative Explanation ◽  
Selection Effect ◽  
Broad Line ◽  
Black Hole Mass ◽  
Cone Model ◽  
Line Region ◽  
Inclination Angles ◽  
Dust Distribution

Abstract The differences between Narrow Line Seyfert 1 galaxies (NLS1s) and Broad Line AGNs (BLAGNs) are not completely understood; it is thought that they may have different inclinations and/or physical characteristics. The FWHM(Hβ)–luminosities correlations are found for NLS1s and their origin is the matter of debate. Here we investigated the spectroscopic parameters and their correlations considering a dusty, cone model of AGN. We apply a simple conical dust distribution (spreading out of broad line region, BLR), assuming that the observed surface of the model is in a good correlation with MIR emission. The dusty cone model in combination with a BLR provides the possibility to estimate luminosity dependence on the cone inclination. The FWHM(Hβ)–luminosities correlations obtained from model in comparison with observational data show similarities which may indicate the influence of AGN inclination and structure to this correlation. An alternative explanation for FWHM(Hβ)–luminosities correlations is the selection effect by the black hole mass. These FWHM(Hβ)–luminosities correlations may be related to the starburst in AGNs, as well. The distinction between spectral properties of the NLS1s and BLAGNs could be caused by multiple effects: beside physical differencies between NLS1s and BLAGNs (NLS1s have lighter black hole mass than BLAGNs), inclination of the conical AGN geometry may have important role as well, where NLS1s may be seen in lower inclination angles.

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