Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 39 for “"supermassive black hole"”.
-
On electromagnetic observables from supermassive black hole accretion flows
… is likely that the jets are powered by spinning supermassive black holes via a dynamical interaction between magnetic fields close to the hole and the warped spacetime predicted by general relativity. This dissertation describes a series of projects aimed at understanding and identifying …
-
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 …
-
Detectability of Self-Lensing Supermassive Black Hole Binaries in Quasars
… objects thought to be powered accretion into supermassive black holes (SMBHs) whose luminosity rivals that of their local galaxy. Since most galaxies are thought to contain SMBHs and galaxies commonly merge, it is likely that some AGN contain two SMBHs. While a few dual-AGN or supermassive …
-
Cosmological Simulations with Resolved Supermassive Black Hole Binary Dynamics and Accretion
… investigates the properties of galaxies and supermassive black hole (SMBH) binaries in cosmological zoom-in simulations. The focus of the study is twofold: first, the agreement between simulated galaxies and observed scaling relations is assessed, followed by an analysis of the impact of …
-
Relativistic Radiative Hydrodynamics Calculation of Accretion Flow into Supermassive Black Hole
… A*) is the nearest and most-intensively-studied supermassive black hole candidate. With a broadband spectrum which likely requires several emission mechanisms for explanation, and structure of innermost accretion flow not yet well constrained, the understanding of accretion into Sgr A* demands …
-
Deep learning application for astrophysics: Supermassive black hole, dark matter substructures, and galaxy morphology
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-08-01
-
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 …
-
Black holes and how to find them : on the detection of compact objects at several scales
… to current detection methods for astrophysical black holes at different scales. The following three chapters correspond to different research projects regarding black hole detection. The second chapter presents the kinematic detection of a supermassive black hole at the center of the dwarf …
-
Star Clusters and Dark Matter as Probes of the Spacetime Geometry of Massive Black Holes
… class of stars orbiting very close to the supermassive black hole at the center of our galaxy, known as Sgr A*, could provide tests of the so-called no-hair theorem of general relativity through the measurement of precessions of their orbital planes. By considering how a distribution of …
-
On the Distances and Energetics of AGN Outflows
… key components in the evolution of super-massive black holes and their host galaxies. As important as these outflows are, we still lack sufficient understanding of their structure and energetics. The majority of the work presented in this thesis involved photoionization modeling of AGN outflows …
-
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 …
-
Extended general relativistic magnetohydrodynamics: Formulation and application to black hole accretion
… in accretion disk theory is that concerning black holes that accrete at a rate much lower than the Eddington rate. The plasma that constitutes the disk is in a regime where the Coulomb mean free path is much larger than the disk, and the collision time scales are larger than the inflow time. …
-
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 …
-
Gravitational waves as direct probes of binary evolution and astrophysical environments
… the detection of a merging heavy stellar-mass black-hole binary. Many such compact binaries have been detected since then and more massive black-hole mergers are expected to be detected as the rest of the gravitational-wave spectrum is opened up in the coming years and decades. Gravity itself, …
-
Exploring fundamental physics with gravitational waves
… for signals from individually resolvable supermassive black hole binaries. The main obstacle to performing efficient searches is the large size of the data sets, which consist of more than one billion stars. A near-lossless compression which reduces the size of the data set by a factor of …
-
Investigating the evolution of red and blue quasars
We investigate the host galaxy and central supermassive black hole (SMBH) accretion properties of a sample of 218 red and blue broadline quasars (AGN with Lₓ > 10⁴⁴ erg/s) to test the predictions of the major merger-driven evolutionary model. Using rich multiwavelength data, we analyze differences …
-
Tests of Gravity Theories with Pulsar Timing
… of a pulsar orbiting in the vicinity of the supermassive black hole SgrA∗ . We approach this problem by deriving an analytical formula based on Einstein’s theory of General Relativity which predicts the propagation time delay in the Kerr space-time and deduces the frame dragging times delay …
-
The Influence of Dark and Ordinary Matter Physics on Galaxy Formation
… of $\sigma_{\rm SI} = 1 $cm$^2$/g delays supermassive black hole growth through mergers by billions of years compared to CDM growth. With the same simulations, we show slow accretion of cold clumps through the circumgalactic medium and onto galaxies is an important process that fuels star …
-
Dissipative heating and nonthermal distributions in black hole accretion flaring events
The center of the Milky Way galaxy contains a supermassive black hole called Sgr A*, which has been observed at radio, mm, X-ray, and near infrared (NIR) wavelengths. The NIR emission flares about once per day with the flaring state being about an order of magnitude brighter than the non-flaring …
-
Magneto-centrifugal Wind with Applications to Astrophysical Accretion Disks
… involves a near Eddington accretion flow onto a supermassive black hole, at a distance from the hole where a viscous disk tends to be gravitationally unstable. We find that the disk magnetization is around unity, which optimally fixes the fraction of the radial mass flow returned to the wind at …
Page 1 of 2