Related papers: Intermediate-Mass Black Holes
The possibility of making stellar mass black holes in supernovae that otherwise produce viable Type II and Ib supernova explosions is discussed and estimates given of their number in the Milky Way Galaxy. Observational diagnostics of…
Stars with an initial mass more than ~25 Msun are thought to ultimately become black holes. Then stellar-mass black holes should be ubiquitous but fewer than 20 have been found in our Galaxy to date, all of which have been found through…
Masses of black holes in nearby galactic nuclei can be measured in a variety of ways, using stellar and gaseous kinematics. Reliable black hole masses are known for several dozen objects, so that demographic questions can start to be…
We report upper limits on the masses of black holes that can be present in the centers of 16 nearby galaxy bulges. These limits for our statistically complete sample were derived from the modeling of the central emission-line widths ([N II]…
Black holes with masses of $\rm 10^6-10^9~M_{\odot}$ dwell in the centers of most galaxies, but their formation mechanisms are not well known. A subdominant dissipative component of dark matter with similar properties to the ordinary…
Intermediate Mass Black Holes (IMBHs) are a class of black holes with masses in the range $10^2 \div 10^5$ $M_\odot$, which can not directly derive from stellar evolution. Looking for these objects and estimating their abundance is…
Formation of primordial black holes (PBHs) on astrophysical mass scales is a natural consequence of inflationary cosmology if the primordial perturbation spectrum has a large and negative running of the spectral index as observationally…
Stellar-mass black holes (BHs), with masses comparable to stars, are a major constituent of our Milky Way galaxy. This chapter describes the landscape of challenging, and long-sought efforts to identify these objects in the Galaxy. The…
Whether intermediate-mass black holes reside in nearby star clusters has remained contested for decades. We address this question by training neural network and random forest regressors on synthetic catalogs generated with the {\sc Rapster}…
In this talk we discuss intermediate mass black holes (IMBHs) by their amplilification of distant sources; MACHO searches have studied event times $2 h \lesssim t_0 \lesssim 2 y$ corresponding masses in the range $10^{-6} M_{\odot} \lesssim…
We present new 5 GHz VLA observations of a sample of 8 active intermediate-mass black holes with masses $10^{4.9} < M < 10^{6.1}\ M_{\odot}$ found in galaxies with stellar masses $M_{*} < 3 \times 10^{9}\ M_{\odot}$. We detected 5 of the 8…
We present a relationship between the black hole mass, stellar mass, and star formation rate of a diverse group of 91 galaxies with dynamically-measured black hole masses. For our sample of galaxies with a variety of morphologies and other…
There is both theoretical expectation and some observational clues that intermediate mass black holes reside in nuclei of globular clusters. In order to find an independent indicator for their existence, we investigate in this paper how an…
Black holes are extremely dense and compact objects from which light cannot escape. There is an overall consensus that black holes exist and many astronomical objects are identified with black holes. White holes were understood as the exact…
A combination of ground-based and spacecraft observations has uncovered two black holes of 10 billion solar masses in the nearby Universe. The finding sheds light on how these cosmic monsters co-evolve with galaxies.
More than 300 supermassive black holes have been detected at redshifts larger than 6, and they are abundant in the centers of local galaxies. Their formation mechanisms, however, are still rather unconstrained. A possible origin of these…
We study eccentric equatorial orbits of a stellar-mass black hole around an intermediate-mass slowly rotating Kerr black hole in the presence of gravitational radiation and a dark matter halo. The stellar-mass companion will inspiral…
Models of superdense star clusters at the center of galaxies are investigated to see whether such objects can be stable and long-lived based on evaporation and collision time-scales and stability criteria. We find that physically reasonable…
Quasars emit more energy than any other objects in the universe, yet are not much bigger than the solar system. We are almost certain that quasars are powered by giant black holes of up to $10^{10}$ times the mass of the Sun, and that black…
Radial velocity studies of X-ray binaries provide the most solid evidence for the existence of stellar-mass black holes. We currently have 20 confirmed cases, with dynamical masses in excess of 3 Msun. Accurate masses have been obtained for…