Related papers: A super massive black hole binary in 3C66B: future…
Supermassive black hole binaries may exist in the centers of active galactic nuclei like quasars and radio galaxies and mergers between galaxies may result in the formation of supermassive binaries during the course of galactic evolution.…
Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a periodic flux…
Supermassive black holes (SMBHs) found in the centers of many galaxies have been recognized to play a fundamental active role in the cosmological structure formation process. In hierarchical formation scenarios, SMBHs are expected to form…
Supermassive black hole binaries (SMBHs) are a fascinating byproduct of galaxy mergers in the hierarchical universe. In the last stage of their orbital evolution, gravitational wave radiation drives the binary inspiral and produces the…
Studying a centi-parsec supermassive black hole binary (SMBHB) would allow us to explore a new parameter space in active galactic nuclei, and these objects are also potential sources of gravitational waves. We report evidence that an SMBHB…
Supermassive binary black holes (SBBHs) are a natural outcome of galaxy mergers. Here we show that low-frequency ($f \leq 10^{-6}$ Hz) quasi-periodic variability observed from cosmic blazar sources can provide substantial inductive support…
Supermassive black hole (SMBH) binary systems are unavoidable outcomes of galaxy mergers. Their dynamics encode information about their formation and growth, the composition of their host galactic nuclei, the evolution of galaxies, and the…
The radio galaxy 0402+379 is believed to host a supermassive black hole binary (SMBHB). The two compact core sources are separated by a projected distance of 7.3 pc, making it the most (spatially) compact resolved SMBHB known. We present…
Supermassive black hole (SMBH) binaries are expected in a Lambda CDM cosmology given that most (if not all) massive galaxies contain a massive black hole at their center. So far, however, direct evidence for such binaries has been elusive.…
Despite solid theoretical and observational grounds for the pairing of supermassive black holes (SMBHs) after galaxy mergers, definitive evidence for the existence of close (sub-parsec) separation SMBH binaries (SMBHBs) approaching merger…
Here we consider the perspective to detect sub-pc super-massive binary black-hole (SMBBH) systems using long-term photometric and spectroscopic monitoring campaigns of active galactic nuclei. This work explores the nature of long-term…
Motivated by observational searches for sub-parsec supermassive black hole binaries (SBHBs) we develop a modular analytic model to determine the likelihood for detection of SBHBs by ongoing spectroscopic surveys. The model combines the…
Supermassive black hole binaries (SMBHBs) should be an inevitable consequence of the hierarchical growth of massive galaxies through mergers, and the strongest sirens of gravitational waves (GWs) in the cosmos. And yet, their direct…
Elusive supermassive black hole binaries (SMBHBs) are thought to be the penultimate stage of galaxy mergers, preceding a final coalescence phase. SMBHBs are sources of continuous gravitational waves, possibly detectable by pulsar timing…
A subparsec supermassive black hole binary (SMBHB) at the center of the galaxy 3C 66B is a promising candidate for continuous gravitational-wave searches with pulsar timing arrays (PTAs). In this work, we search for such a signal in the…
Merging compact black-hole (BH) binaries are likely to exist in the nuclear star clusters around supermassive BHs (SMBHs), such as Sgr A$^\ast$. They may also form in the accretion disks of active galactic nuclei. Such compact binaries can…
Supermassive black hole binaries (SMBHs) are expected to result from galaxy mergers, and thus are natural byproducts (and probes) of hierarchical structure formation in the Universe. They are also the primary expected source of…
Supermassive black hole binaries (SMBHBs) in galactic nuclei are thought to be a common by-product of major galaxy mergers. We use simple disk models for the circumbinary gas and for the binary-disk interaction to follow the orbital decay…
The most massive black holes in our Universe form binaries at the centre of merging galaxies. The recent evidence for a gravitational-wave (GW) background from pulsar timing may constitute the first observation that these supermassive black…
Here we discuss the possibility of super-massive binary black hole (SMBBH) detection, using the shifts of the broad lines emitted from a binary system. We perform a number of simulations of shapes and shifts of $H_{\beta}$ lines emitted…