scholarly journals The distribution of supermassive black holes in the nuclei of nearby galaxies

1999 ◽  
Vol 308 (1) ◽  
pp. 77-81 ◽  
Author(s):  
Andrea Cattaneo ◽  
Martin G. Haehnelt ◽  
Martin J. Rees
Keyword(s):  
Black Holes ◽  
Supermassive Black Holes ◽  
Nearby Galaxies

scholarly journals Upper limits on the mass of supermassive black holes from STIS archival data

2007 ◽  
Vol 3 (S245) ◽  
pp. 233-234
Author(s):  
A. Beifiori ◽  
E. M. Corsini ◽  
E. Dalla Bontà ◽  
A. Pizzella ◽  
L. Coccato ◽  
...  
Keyword(s):  
Black Holes ◽  
Emission Line ◽  
Supermassive Black Holes ◽  
Archival Data ◽  
Early Type ◽  
Preliminary Results ◽  
Upper Limits ◽  
Nearby Galaxies ◽  
Line Widths

AbstractThe growth of supermassive black holes (SMBHs) appears to be closely linked with the formation of spheroids. There is a pressing need to acquire better statistics on SMBH masses, since the existing samples are preferentially weighted toward early-type galaxies with very massive SMBHs. With this motivation we started a project aimed at measuring upper limits on the mass of the SMBHs that can be present in the center of all the nearby galaxies (D < 100 Mpc) for which STIS/G750M spectra are available in the HST archive. These upper limits will be derived by modeling the central emission-line widths ([N II] λλ6548, 6583, Hα and [S II] λλ6716, 6731) observed over an aperture of ~01 (R < 50 pc). Here we present our preliminary results for a subsample of 76 bulges.

scholarly journals Stringent limits on the masses of the supermassive black holes in seven nearby galaxies

2017 ◽  
Vol 338 (7) ◽  
pp. 841-853 ◽  
Author(s):  
I. Pagotto ◽  
E. M. Corsini ◽  
E. Dalla Bontà ◽  
A. Beifiori ◽  
L. Costantin ◽  
...  
Keyword(s):  
Black Holes ◽  
Supermassive Black Holes ◽  
Nearby Galaxies ◽  
The Masses

scholarly journals Upper limits on the mass of supermassive black holes from HST/STIS archival data

2006 ◽  
Vol 2 (S238) ◽  
pp. 349-350
Author(s):  
E. M. Corsini ◽  
A. Beifiori ◽  
E. Dalla Bontà ◽  
A. Pizzella ◽  
L. Coccato ◽  
...  
Keyword(s):  
Black Holes ◽  
Emission Line ◽  
Supermassive Black Holes ◽  
Archival Data ◽  
Early Type ◽  
Upper Limits ◽  
Nearby Galaxies ◽  
Line Widths

AbstractThe growth of supermassive black holes (SBHs) appears to be closely linked with the formation of spheroids. There is a pressing need to acquire better statistics on SBH masses, since the existing samples are preferentially weighted toward early-type galaxies with very massive SBHs. With this motivation we started a project aimed at measuring upper limits on the mass of the SBHs in the center of all the nearby galaxies (D < 100 Mpc) for which STIS/G750M spectra are available in the HST archive. These upper limits will be derived by modeling the central emission-line widths observed in the Hα region over an aperture of ∼0.1″. Here we present our results for a subsample of 22 S0-Sb galaxies within 20 Mpc.

scholarly journals Giant-Amplitude X-ray Flares as Probes of the Black Hole Region of Nearby Galaxies

2003 ◽  
Vol 214 ◽  
pp. 243-245
Author(s):  
Stefanie Komossa ◽  
Weimin Yuan ◽  
Da Wei Xu
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Supermassive Black Holes ◽  
Active Galaxies ◽  
Tidal Disruption ◽  
X Ray ◽  
Nearby Galaxies ◽  
Deep Fields

In the last few years, several giant-amplitude, non-recurrent X-ray flares have been observed from optically non-active galaxies. The observations were interpreted in terms of the long-predicted tidal disruption flares of stars captured by supermassive black holes. In this contribution, we review the observations and interpretation of the X-ray flares and add some new thoughts. Future X-ray observations of the flare events are expected to open up a new window to detect and investigate SMBHs and their immediate environment in galaxies. Here, we concentrate on the possibility to detect new X-ray flares in deep fields with the planned European X-ray mission XEUS.

scholarly journals HUNTING FOR SUPERMASSIVE BLACK HOLES IN NEARBY GALAXIES WITH THE HOBBY–EBERLY TELESCOPE

2015 ◽  
Vol 218 (1) ◽  
pp. 10 ◽  
Author(s):  
Remco C. E. van den Bosch ◽  
Karl Gebhardt ◽  
Kayhan Gültekin ◽  
Akin Yıldırım ◽  
Jonelle L. Walsh
Keyword(s):  
Black Holes ◽  
Supermassive Black Holes ◽  
Nearby Galaxies

scholarly journals Black holes: from stars to galaxies

2006 ◽  
Vol 2 (S238) ◽  
pp. 309-314 ◽  
Author(s):  
I. Félix Mirabel
Keyword(s):  
Black Holes ◽  
Binary Systems ◽  
Stellar Mass ◽  
Supermassive Black Holes ◽  
Intermediate Mass ◽  
X Ray ◽  
Nearby Galaxies ◽  
Intermediate Mass Black Holes

AbstractWhile until recently they were often considered as exotic objects of dubious existence, in the last decades there have been overwhelming observational evidences for the presence of stellar mass black holes in binary systems, supermassive black holes at the centers of galaxies, and possibly, intermediate-mass black holes observed as ultraluminous X-ray sources in nearby galaxies. Black holes are now widely accepted as real physical entities that play an important role in several areas of modern astrophysics.Here I review the concluding remarks of the IAU Symposium No 238 on Black Holes, with particular emphasis on the topical questions in this area of research.

scholarly journals Observational Evidence for Supermassive Black Holes

1989 ◽  
Vol 134 ◽  
pp. 217-232
Author(s):  
Alan Dressler
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Hubble Space Telescope ◽  
Stellar Dynamics ◽  
Supermassive Black Holes ◽  
Massive Black Hole ◽  
Central Mass ◽  
Nearby Galaxies ◽  
Straightforward Interpretation ◽  
Rule Out

A growing body of evidence from stellar dynamics in the nuclei of galaxies indicates that supermassive black holes of 107–109 M0 are common. The two best cases are M31 and M32, for which dark, central mass concentrations are the only straightforward interpretation. M87 continues to be a possible location of an even more massive black hole, but new observations and models by the author and D. Richstone effectively rule out the high black hole mass ∼5 × 109 M0 claimed by Sargent, Young, and collaborators. New data are available for several other nearby galaxies which also show kinematic signatures that could also be due to supermassive black holes. The Hubble Space Telescope will play the key role in strengthening these cases and eliminating, for the best examples, alternative models which do not require supermassive black holes.

scholarly journals Epicyclic Oscillations around Simpson–Visser Regular Black Holes and Wormholes

Universe ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 279
Author(s):  
Zdeněk Stuchlík ◽  
Jaroslav Vrba
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Active Galactic Nuclei ◽  
Observational Data ◽  
High Frequency ◽  
Galactic Nuclei ◽  
Supermassive Black Holes ◽  
Periodic Oscillations ◽  
High Length ◽  
Circular Geodesic

We study epicyclic oscillatory motion along circular geodesics of the Simpson–Visser meta-geometry describing in a unique way regular black-bounce black holes and reflection-symmetric wormholes by using a length parameter l. We give the frequencies of the orbital and epicyclic motion in a Keplerian disc with inner edge at the innermost circular geodesic located above the black hole outer horizon or on the our side of the wormhole. We use these frequencies in the epicyclic resonance version of the so-called geodesic models of high-frequency quasi-periodic oscillations (HF QPOs) observed in microquasars and around supermassive black holes in active galactic nuclei to test the ability of this meta-geometry to improve the fitting of HF QPOs observational data from the surrounding of supermassive black holes. We demonstrate that this is really possible for wormholes with sufficiently high length parameter l.

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.

scholarly journals The ecology of the galactic centre: Nuclear stellar clusters and supermassive black holes

2019 ◽  
Vol 14 (S351) ◽  
pp. 80-83 ◽  
Author(s):  
Melvyn B. Davies ◽  
Abbas Askar ◽  
Ross P. Church
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Large Fraction ◽  
Galactic Nuclei ◽  
Supermassive Black Holes ◽  
Galactic Centre ◽  
Stellar Clusters ◽  
Stellar Cluster ◽  
Supermassive Black Hole ◽  
Multiple Clusters

AbstractSupermassive black holes are found in most galactic nuclei. A large fraction of these nuclei also contain a nuclear stellar cluster surrounding the black hole. Here we consider the idea that the nuclear stellar cluster formed first and that the supermassive black hole grew later. In particular we consider the merger of three stellar clusters to form a nuclear stellar cluster, where some of these clusters contain a single intermediate-mass black hole (IMBH). In the cases where multiple clusters contain IMBHs, we discuss whether the black holes are likely to merge and whether such mergers are likely to result in the ejection of the merged black hole from the nuclear stellar cluster. In some cases, no supermassive black hole will form as any merger product is not retained. This is a natural pathway to explain those galactic nuclei that contain a nuclear stellar cluster but apparently lack a supermassive black hole; M33 being a nearby example. Alternatively, if an IMBH merger product is retained within the nuclear stellar cluster, it may subsequently grow, e.g. via the tidal disruption of stars, to form a supermassive black hole.

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