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We present Chandra observations of 12 galaxies that contain supermassive black holes with dynamical mass measurements. Each galaxy was observed for 30 ksec and resulted in a total of 68 point source detections in the target galaxies including supermassive black hole sources, ultraluminous X-ray sources, and extragalactic X-ray binaries. Based on our fits of the X-ray spectra, we report fluxes, luminosities, Eddington ratios, and slope of the power-law spectrum. Normalized to the Eddington luminosity, the 2--10 keV band X-ray luminosities of the SMBH sources range from $10^{-8}$ to $10^{-6}$, and the power-law slopes are centered at $sim2$ with a slight trend towards steeper (softer) slopes at smaller Eddington fractions, implying a change in the physical processes responsible for their emission at low accretion rates. We find 20 ULX candidates, of which six are likely ($>90%$ chance) to be true ULXs. The most promising ULX candidate has an isotropic luminosity in the 0.3--10 keV band of $1.0_{-0.3}^{+0.6} times 10^{40}$ erg/s.
We investigate the evolution of supermassive binary black holes (BBHs) in galaxies with realistic property distributions and the gravitational-wave (GW) radiation from the cosmic population of these BBHs. We incorporate a comprehensive treatment of t
Black hole accretion and jet production are areas of intensive study in astrophysics. Recent work has found a relation between radio luminosity, X-ray luminosity, and black hole mass. With the assumption that radio and X-ray luminosity are suitable p
Gas undergoing Bondi accretion onto a supermassive black hole (SMBH) becomes hotter toward smaller radii. We searched for this signature with a Chandra observation of the hot gas in NGC 3115, which optical observations show has a very massive SMBH. O
Understanding the processes that drive galaxy formation and shape the observed properties of galaxies is one of the most interesting and challenging frontier problems of modern astrophysics. We now know that the evolution of galaxies is critically sh
We study the disk-jet connection in supermassive black holes by investigating the properties of their optical and radio emissions utilizing the SDSS-DR7 and the NVSS catalogs. Our sample contains 7017 radio-loud quasars with detection both at 1.4~GHz