124 datasets found

Supermassive black hole binaries (SMBHBs) should form frequently in galactic nuclei as a result of galaxy mergers. At subparsec separations, binaries become strong sources of...

We revisit the dependence of the covering factor (CF) of dust torus on physical properties of active galactic nuclei (AGNs) by taking into account an AGN polar dust emission....

Narrow-line Seyfert 1 galaxies (NLS1s) are believed to be powered by the accretion of matter onto low-mass black holes (BHs) in spiral host galaxies with BH masses...

Using different kinds of velocity tracers derived from the broad H{beta} profile (in the mean or rms spectrum) and the corresponding virial factors f, the central supermassive...

We present optical light curves from the Transiting Exoplanet Survey Satellite (TESS) for the archetypical dwarf active galactic nucleus (AGN) in the nearby galaxy NGC 4395...

The tight correlations between supermassive black hole (SMBH) mass (MBH) and the properties of the host galaxy have useful implications for our understanding of the growth of...

The uncharted territory of the high-redshift (z>~3) universe holds the key to understanding the evolution of quasars. In an attempt to identify the most extreme members of...

We present a multiwavelength study of the active galactic nucleus in the nearby (D=14.1Mpc) low-mass galaxy IC750, which has circumnuclear 22GHz water maser emission. The masers...

We investigate whether the correlation between the hard X-ray photon index ({Gamma}) and accretion rate for super-Eddington accreting quasars is different from that for...

We present a detailed timing analysis of the bright black hole X-ray binary MAXI J1820+070 (ASASSN-18ey), during its first detected outburst lasting from 2018 March until 2019...

We present a sample of nearby dwarf galaxies with radio-selected accreting massive black holes (BHs), the majority of which are non-nuclear. We observed 111 galaxies using...

The radius-luminosity (R_H{beta}-L_5100) relationship of active galactic nuclei (AGNs) established by the reverberation mapping (RM) observations has been widely used as a...

We compiled a sample of 73 active galactic nuclei (AGNs) with reverberation mapping (RM) observations from RM campaigns, including our ongoing campaign of monitoring...

We report initial results from a large Gemini program to observe z>~5.7 quasars with GNIRS near-IR spectroscopy. Our sample includes 50 quasars with simultaneous...

Black hole mass scaling relations suggest that extremely massive black holes (EMBHs) with M_BH_>~10^9.4^M_{sun} are found in the most massive galaxies with...

Nearby galaxy surveys have long classified X-ray binaries (XRBs) by the mass category of their donor stars (high-mass and low-mass). The NuSTAR observatory, which provides...

As one paper in a series reporting on a large reverberation mapping campaign of super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs), we...

We present high-resolution (submas) Very Long Baseline Interferometry maps of nuclear H_2_O megamasers for seven galaxies. In UGC 6093, the well-aligned systemic masers and...

A recent study of a small sample of X-ray binaries (XRBs) suggests a significant softening of spectra of neutron star (NS) binaries as compared to black hole (BH) binaries in...

We describe the discovery of a solar neighborhood (d=468pc) binary system with a main-sequence sunlike star and a massive noninteracting black hole candidate. The spectral...