Related papers: A normal supermassive black hole in NGC 1277
The black hole mass measurement in active galaxies is a challenge, particularly in sources where the reverberation method cannot be applied. We aim to determine the black hole mass in a very special object, RE J1034+396, one of the two AGN…
As a part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, we present an estimate of the mass of the supermassive black hole (SMBH) in the nearby fast-rotator early-type galaxy NGC 3665. We obtained Combined…
We have obtained long-slit observations of the circumnuclear region of M87 at three different locations, with a spatial sampling of 0.028" using the Faint Object Camera f/48 spectrograph on board HST. These data allow us to determine the…
A supermassive black hole SgrA* with the mass ~4x10^6 Msun resides at the centre of our galaxy. Building up such a massive black hole within the ~10^10 year lifetime of our galaxy would require a mean accretion rate of ~4x10^-4 Msun/yr. At…
The results of photometric CCD monitoring and spectral observations of the black hole binary and microquasar V4641 Sgr in the quiet state are presented. The ellipsoidal light curve with large amplitude of 0.36^m in R band suggests the…
We present new Space Telescope Imaging Spectrograph (STIS) observations of three spiral galaxies, NGC 4303, NGC 3310 and NGC 4258. The bright optical emission lines H$\alpha$ $\lambda$ $6564 \AA$, [NII] $\lambda$$\lambda$ $6549,6585 \AA$…
Naturally occurring water vapor maser emission at 1.35 cm wavelength provides an accurate probe for the study of accretion disks around highly compact objects, thought to be black holes, in the centers of active galaxies. Because of the…
We report the detection of a black hole (NGC 1850 BH1) in the $\sim$100 Myr-old massive cluster NGC~1850 in the Large Magellanic Cloud. It is in a binary system with a main-sequence turn-off star (4.9 $\pm$ 0.4 M${_\odot}$), which is…
Supermassive black holes in giant elliptical galaxies are remarkably faint given their expected accretion rates. This motivates models of radiatively inefficient accretion, due to either ion-electron thermal decoupling, generation of…
Galaxies that contain bulges appear to contain central black holes whose masses correlate with the velocity dispersion of the bulge. We show that no corresponding relationship applies in the pure disk galaxy M33. Three-integral dynamical…
NGC 4258 is an SABbc Seyfert galaxy, located at a distance of $7.2 \pm 0.3$ Mpc. This object is well known by its nearly edge-on molecular nuclear disc, located between 0.16 and 0.28 pc from the nucleus, whose H$_2$O maser emission allows a…
Ultracompact dwarf galaxies (UCDs) are among the densest stellar systems in the universe. These systems have masses up to 200 million solar masses, but half light radii of just 3-50 parsecs. Dynamical mass estimates show that many UCDs are…
Observational work conducted over the last few decades indicates that all massive galaxies have supermassive black holes at their centres. Although the luminosities and brightness fluctuations of quasars in the early Universe suggest that…
The masses of supermassive black holes correlate almost perfectly with the velocity dispersions of their host bulges, M(BH) ~ sigma^alpha, where alpha =4.8 +/- 0.5$. The relation is much tighter than the relation between M(BH) and bulge…
We present new multi-wavelength observations of the dwarf Seyfert 1 galaxy POX 52 in order to investigate the properties of the host galaxy and the active nucleus, and to examine the mass of its black hole, previously estimated to be ~ 10^5…
We present a measurement of the supermassive black hole (SMBH) mass of the nearby lenticular galaxy NGC 383, based on Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of the $^{12}$CO(2-1) emission line with an angular…
Jet ejection by accreting black holes is a mass invariant mechanism unifying stellar and supermassive black holes (SMBHs) that should also apply for intermediate-mass black holes (IMBHs), which are thought to be the seeds from which SMBHs…
We dissect giant Sc-Scd galaxies with Hubble Space Telescope photometry and Hobby-Eberly Telescope spectroscopy. We use HET's High Resolution Spectrograph (resolution = 15,000) to measure stellar velocity dispersions in the nuclear star…
Spin measurements of supermassive black holes (SMBHs) provide crucial constraints on the accretion processes that power active galactic nuclei (AGN), fuel outflows, and trigger black hole growth. However, spin measurements are mainly…
Recently, the Event Horizon Telescope (EHT) achieved the realization of an image of the supermassive black hole $\textrm{Sgr~A}^\star$ showing an angular shadow diameter $\mathcal{D}= 48.7 \pm 7\mu as$ and the fractional deviation…