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Showing 1 to 20 of 43 for “"Supermassive Black Holes"”.
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Demographics of supermassive black holes
Supermassive black holes are a fundamental component of the universe in general and of galaxies in particular. Almost every massive galaxy harbours a supermassive black hole (SMBH) in its center. Furthermore, there is a close connection between the growth of the SMBH and the evolution of its host …
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Hunting Supermassive Black Holes in the Early Universe
Supermassive black holes (SMBHs) hold the essential ingredient into understanding the galaxy formation and evolution across cosmic time. The physical properties of SMBH are found to tightly correlated with host galaxies in local universe. Whether such relationship apply in the early universe …
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Reverberation Mapping of Supermassive Black Holes using Machine Learning
Accreting supermassive black holes at the centers of galaxies, known as active galactic nuclei (AGN), offer a unique window into the physics of accretion and feedback that shape galactic evolution. Yet, the small spatial scales of these regions remain inaccessible to direct imaging. Reverberation …
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Modeling the cosmological co-evolution of supermassive black holes and galaxies
… we investigate the cosmological co-evolution of supermassive black holes (BHs), Active Galactic Nuclei (AGN) and their hosting dark matter (DM) halos and galaxies, within the standard CDM scenario. We analyze both analytic, semi-analytic and hybrid techniques and use the most recent observational …
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Searching for binary and dual supermassive black holes in large surveys
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms
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Constraining the Initial Conditions and Final Outcomes of Accretion Processes around Young Stars and Supermassive Black Holes
… around young stars and protostars and around the supermassive black hole at the galactic center. I begin by describing adaptive optics-fed infrared spectroscopic studies of nascent and newborn binary systems. Binary star formation is a significant mode of star formation that could be responsible …
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Primordial black hole seeding from hybrid inflation : the direct integration approach
We examine the notion that supermassive black holes at the centre of galaxies, such as the Milky Way, could have been seeded in the early universe by the mechanisms of hybrid inflation. Using luminosity data, we estimate the current density of supermassive black hole. We develop the formalism of …
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Mergers of Supermassive Black Hole Binaries in Gas-rich Environments: Models of Event Rates and Electromagnetic Signatures
Supermassive black holes permeate the observable Universe, residing in the nuclei of all or nearly all nearby massive galaxies and powering luminous quasars as far as ten billion light years away. These monstrous objects must grow through a combination of gas accretion and mergers of less massive …
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Studying Accretion Disc Winds with X-ray Spectroscopy
… in most types of accreting systems including supermassive black holes, classical X-ray binaries and Ultraluminous X-ray sources. Outflows form a ubiquitous and important part of the accretion flow, carrying away a considerable fraction of the originally infalling mass. With velocities as high …
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A study in spherical accretion of self-gravitating fluids in a general relativistic framework
… of a self-gravitating fluid onto a central black hole is introduced in stationary coordinates for an observer at infinity. The important feature of gravitational backreaction due to a self-gravitating fluid on the metric is included in the model. The model is solved numerically for the most …
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The Mass-Pitch Angle Relation for Three High Redshift Active Galaxies Selected from the GOODS Field
… wells at the center of all galaxies. These supermassive black holes at a galaxies nucleus formed in the company of the other features making up the galaxy, particularly spiral arms. With nearby galaxies showing a relationship between the spiral arm pitch angle and that central mass, here we …
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Quasi-stars and the Schönberg–Chandrasekhar limit
The mechanism by which the supermassive black holes that power bright quasars at high redshift form remains unknown. One possibility is that, if fragmentation is prevented, the monolithic collapse of a massive protogalactic disc proceeds via a cascade of triaxial instabilities and leads to the …
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Gravitational instability and fragmentation of self-gravitating accretion disks
We know from observations that supermassive black holes (SMBH) of masses up to $10^{10} \msol$ existed in quasars when the universe was only about $10^9$ years old. The rapid formation of SMBHs can be understood as the outcome of the collision of two large gas-rich galaxies followed by disk …
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Hybrid and multifield inflation
… which could conceivably seed the formation of black holes that can evolve to become the supermassive black holes found at the centers of galaxies. Apart from numerically calculating the resulting spectrum, we derived an expansion in the number of waterfall fields, which makes the calculation …
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No evidence for millimeter continuum source overdensities in the environments of z [greater than approximately] 6 quasars
Bright high-redshift quasars (z > 6), hosting supermassive black holes (M [subscript BH] > 10⁸M [subscript circled dot]), are expected to reside in massive host galaxies embedded within some of the earliest, most massive galaxy overdensities. We analyze 1.2mm ALMA dust continuum maps of 35 bright …
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Radiative signatures of the jet launching region in astronomical objects
… jets are observed in a wide range of accreting black hole systems, from stellar-mass black holes in X-ray binaries (XRBs), to supermassive black holes in active galactic nuclei (AGN). However, despite decades of observational and theoretical research, the mechanism by which relativistic jets are …
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Evolution of Supermassive Black Hole Feedback in Galaxy Clusters
… and triggering of feedback from the largest supermassive black holes (SMBHs) residing in them. This cooling and subsequent feedback from these active galactic nuclei (AGN) is the primary driver of the baryon cycle and evolution of the largest, brightest cluster galaxies (BCGs), quenching …
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Dense stellar systems and massive black holes
… of the cardinal predictions of this theory are black holes. Massive, dark objects are found in the majority of galaxies. Our own galactic center very contains such an object with a mass of about four million solar masses. Are these objects supermassive black holes (SMBHs), or do we need …
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