相关论文: The isotropic center of NGC 5419 -- A core in form…
We obtained adaptive-optics assisted SINFONI observations of the central regions of the giant elliptical galaxy NGC5419 with a spatial resolution of 0.2 arcsec ($\approx 55$ pc). NGC5419 has a large depleted stellar core with a radius of…
Given its velocity dispersion, the early-type galaxy NGC 1600 has an unusually massive ($M_\bullet = 1.7 \times 10^{10} M_\odot$) central supermassive black hole (SMBH), surrounded by a large core ($r_\mathrm{b} = 0.7$ kpc) with a…
We study the impact of merging supermassive black holes (SMBHs) on the central regions of massive early-type galaxies (ETGs) using a series of merger simulations with varying mass ratios. The ETG models include realistic stellar and dark…
The stellar kinematics of the dwarf elliptical galaxy NGC 4486B have been measured in seeing sigma_* = .22 arcsec with the Canada-France-Hawaii Telescope. Lauer et al. 1996, ApJ, 471, L79 have shown that NGC 4486B is similar to M31 in…
We have analysed a new high-resolution e-MERLIN 1.5 GHz radio continuum map together with $HST$ and SDSS imaging of NGC 5322, an elliptical galaxy hosting radio jets, aiming to understand the galaxy's central structure and its connection to…
Massive early-type galaxies (ETGs) are believed to form primarily through mergers of less massive progenitors, leaving behind numerous traces of violent formation histories, such as stellar streams and shells. A particularly striking…
Deep exposure imaging of early-type galaxies (ETGs) are revealing the second-order complexity of these objects, which have been long considered uniform, dispersion-supported spheroidals. "Fine structure" features (e.g. ripples, plumes,…
The most massive elliptical galaxies have low-density centers or cores that differ dramatically from the high-density centers of less massive ellipticals and bulges of disk galaxies. These cores have been interpreted as the result of…
A recent study of the compact elliptical galaxy NGC 4486B using JWST-NIRSpec IFU kinematics confirmed a supermassive black hole (SMBH) of mass $M_{BH}=3.6\pm0.7\times10^8$ (~8% of the stellar mass). In addition to its double nucleus, the…
The inspiral of a turbulent molecular cloud in the Galactic Centre may result in the formation of a small, dense and moderately eccentric gas disc around the supermassive black hole (SMBH). Such a disc is unstable to fragmentation and may…
We investigated whether the two recently discovered nuclei in NGC7727 both host a super-massive black hole (SMBH). We used the high spatial resolution mode of the integral-field spectrograph MUSE on the VLT in adaptive optics mode to…
The centre of our Galaxy is one of the most studied and yet enigmatic places in the Universe. At a distance of about 8 kpc from our Sun, the Galactic centre (GC) is the ideal environment to study the extreme processes that take place in the…
We have developed a new method for post-Newtonian, high-precision integration of stellar systems containing a super-massive black hole (SMBH), splitting the forces on a particle between a dominant central force and perturbations. We used…
Scouring by supermassive black hole (SMBH) binaries is the most accepted mechanism for the formation of the cores seen in giant elliptical galaxies. However, an additional mechanism is required to explain the largest observed cores.…
We report the discovery of an active intermediate-mass black hole (IMBH) candidate in the center of nearby barred bulgeless galaxy $\rm NGC~3319$. The point X-ray source revealed by archival Chandra and XMM-Newton observations is spatially…
Globular clusters (GCs) may harbour intermediate-mass black holes (IMBHs) at their centres. In these dynamically active environments stellar-mass black holes (SBHs) sink to the center soon after formation, due to dynamical friction and…
The formation of supermassive black holes (SMBHs) in early-type galaxies (ETGs) is a key challenge for galaxy formation theories. Using the monolithic collapse models of ETGs formed in Milgromian Dynamics (MOND) from Eappen et al. (2022),…
We analyze proper motions from the Hubble Space Telescope (HST) and the second Gaia data release along with line-of-sight velocities from the MUSE spectrograph to detect imprints of an intermediate-mass black hole (IMBH) in the center of…
As a natural consequence of cosmological hierarchical structure formation, sub-parsec supermassive black hole binaries (SMBHBs) should be common in galaxies but thus far have eluded spectroscopic identification. Based on four decades of…
Context. A dual active galactic nucleus candidate with a separation of only 500 pc was recently found in NGC 7727. According to the hierarchical merging scenario, such objects would be expected to merge on a timescale of a few hundred Myr.…