scholarly journals The nature of massive black hole binary candidates – II. Spectral energy distribution atlas

2014 ◽  
Vol 441 (1) ◽  
pp. 316-332 ◽  
Author(s):  
E. Lusso ◽  
R. Decarli ◽  
M. Dotti ◽  
C. Montuori ◽  
David W. Hogg ◽  
...  
2012 ◽  
Vol 8 (S290) ◽  
pp. 355-356
Author(s):  
George Younes ◽  
Delphine Porquet

AbstractWe study the multiwavelength properties of an optically selected sample of Low Ionization Nuclear Emission-line Regions (LINERs), in an attempt to determine the accretion mechanism powering their central engine. We show how their X-ray spectral characteristics, and their spectral energy distribution compare to luminous AGN, and briefly discuss their connection to their less massive counter-parts galactic black-hole X-ray binaries.


2007 ◽  
Vol 670 (1) ◽  
pp. 600-609 ◽  
Author(s):  
Elena Gallo ◽  
Simone Migliari ◽  
Sera Markoff ◽  
John A. Tomsick ◽  
Charles D. Bailyn ◽  
...  

2020 ◽  
Vol 494 (1) ◽  
pp. 571-583 ◽  
Author(s):  
T Bassi ◽  
J Malzac ◽  
M Del Santo ◽  
E Jourdain ◽  
J-P Roques ◽  
...  

ABSTRACT The black hole transient GRS 1716−249 was monitored from the radio to the γ-ray band during its 2016–2017 outburst. This paper focuses on the spectral energy distribution (SED) obtained in 2017 February–March, when GRS 1716−249 was in a bright hard spectral state. The soft γ-ray data collected with the INTEGRAL/SPI telescope show the presence of a spectral component that is in excess of the thermal Comptonization emission. This component is usually interpreted as inverse Compton emission from a tiny fraction of non-thermal electrons in the X-ray corona. We find that hybrid thermal/non-thermal Comptonization models provide a good fit to the X-/γ-ray spectrum of GRS 1716−249. The best-fitting parameters are typical of the bright hard state spectra observed in other black hole X-ray binaries. Moreover, the magnetized hybrid Comptonization model belm provides an upper limit on the intensity of the coronal magnetic field of about 106 G. Alternatively, this soft γ-ray emission could originate from synchrotron emission in the radio jet. In order to test this hypothesis, we fit the SED with the irradiated disc plus Comptonization model combined with the jet internal shock emission model ishem. We found that a jet with an electron distribution of p ≃ 2.1 can reproduce the soft γ-ray emission of GRS 1716−249. However, if we introduce the expected cooling break around 10 keV, the jet model can no longer explain the observed soft γ-ray emission, unless the index of the electron energy distribution is significantly harder (p < 2).


2006 ◽  
Vol 2 (S238) ◽  
pp. 165-169
Author(s):  
Daniel Proga

AbstractI present results from numerical simulations of gas dynamics outside luminous accretion disks in active galactic nuclei. The gas, gravitationally captured by a super massive black hole, can be driven away by the energy and momentum of the radiation emitted during black hole accretion. Assuming axisymmetry, I study how the mass accretion and outflow rates, and the flow dynamics respond to changes in radiation heating relative to radiation pressure.I find that for a 108M⊙ black hole with the accretion luminosity of 0.6 of the Eddington luminosity the flow settles into a steady state and has two components: (1) an equatorial inflow and (2) a bipolar inflow/outflow with the outflow leaving the system along the disk rotational axis. The inflow is a realization of a Bondi–like accretion flow. The second component is an example of a non-radial accretion flow which becomes an outflow once it is pushed close to the rotational axis where thermal expansion and radiation pressure accelerate it outward.The main result of this preliminary work is that although the above two-component solution is robust, its properties are sensitive to the geometry and spectral energy distribution of the radiation field.


2018 ◽  
Vol 620 ◽  
pp. L3 ◽  
Author(s):  
K. Matsuoka ◽  
Y. Toba ◽  
M. Shidatsu ◽  
Y. Ueda ◽  
K. Iwasawa ◽  
...  

We present a near-infrared (NIR) spectrum of WISE J104222.11+164115.3, an extremely red dust-obscured galaxy (DOG), which has been observed with the Long-slit Intermediate Resolution Infrared Spectrograph (LIRIS) on the 4.2m William Hershel Telescope. This object was selected as a hyper-luminous DOG candidate at z ∼ 2 by combining the optical and IR photometric data based on the Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE), although its redshift had not yet been confirmed. Based on the LIRIS observation, we confirmed its redshift of 2.521 and total IR luminosity of log(LIR/L⊙) = 14.57, which satisfies the criterion for an extremely luminous IR galaxy (ELIRG). Moreover, we indicate that this object seems to have an extremely massive black hole with MBH = 1010.92 M⊙ based on the broad Hα line: the host stellar mass is derived as M⋆ = 1013.55 M⊙ by a fit of the spectral energy distribution. Very recently, it has been reported that this object is an anomalous gravitationally lensed quasar based on near-IR high-resolution imaging data obtained with the Hubble Space Telescope. Its magnification factor has also been estimated with some uncertainty (i.e., μ = 53−122). We investigate the ratio of the black hole to galaxy mass, which is less strongly affected by a lensing magnification factor, instead of the absolute values of the luminosities and masses. We find that the MBH/M⋆ ratio (i.e., 0.0140–0.0204) is significantly higher than the local relation, following a sequence of unobscured quasars instead of obscured objects (e.g., submillimeter galaxies) at the same redshift. Moreover, the LIRIS spectrum shows strongly blueshifted oxygen lines with an outflowing velocity of ∼1100 km s−1, and our Swift X-ray observation also supports that this source is an absorbed AGN with an intrinsic column density of NHint = 4.9 × 1023 cm−2. These results imply that WISE J104222.11+164115.3 is in a blow-out phase at the end of the buried rapid black hole growth.


2010 ◽  
Vol 6 (S275) ◽  
pp. 82-86 ◽  
Author(s):  
Dipankar Maitra ◽  
Andrew Cantrell ◽  
Sera Markoff ◽  
Heino Falcke ◽  
Jon Miller ◽  
...  

AbstractWe present results of recent observations and theoretical modeling of data from black holes accreting at very low luminosities (L/LEdd ≲ 10−8). We discuss our newly developed time-dependent model for episodic ejection of relativistic plasma within a jet framework, and a successful application of this model to describe the origin of radio flares seen in Sgr A*, the Galactic center black hole. Both the observed time lags and size-frequency relationships are reproduced well by the model. We also discuss results from new Spitzer data of the stellar black hole X-ray binary system A0620–00. Complemented by long term SMARTS monitoring, these observations indicate that once the contribution from the accretion disk and the donor star are properly included, the residual mid-IR spectral energy distribution of A0620–00 is quite flat and consistent with a non-thermal origin. The results above suggest that a significant fraction of the observed spectral energy distribution originating near black holes accreting at low luminosities could result from a mildly relativistic outflow. The fact that these outflows are seen in both stellar-mass black holes as well as in supermassive black holes at the heart of AGNs strengthens our expectation that accretion and jet physics scales with mass.


2011 ◽  
Vol 20 (3) ◽  
Author(s):  
S. Simić ◽  
L. Č. Popović ◽  
P. Jovanović

AbstractHere we consider the influence of microlensing on the spectrum of a lensed object with the angular size 5 μas accepting that the composite emission of this object originates from three different regions arranged around its center. We assume that the lensed object has three concentric regions with a black-body emission; the temperatures of these regions are 10 000 K, 7500 K and 5000 K. We investigate how the integral spectral energy distribution (SED) of such stratified source changes due to microlensing by a group of solarmass stars. We find that the SED and flux ratios in the photometric B, V and R passbands show considerable changes during a microlens event. This indicates that the flux anomaly observed in some lensed quasars may be caused by microlensing of a stratified object.


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