Related papers: Central mass accumulation in nuclear spirals
Nuclear spirals naturally form as a gas response to non-axisymmetry in the galactic potential, even if the degree of this asymmetry is very small. Linear wave theory well describes weak nuclear spirals, but spirals induced by stronger…
Recent high-resolution observations indicate that nuclear spirals are often present in the innermost few hundred parsecs of disc galaxies. My models show that nuclear spirals form naturally as a gas response to non-axisymmetry in the…
Nuclear spirals can provide a wealth of information about the nuclear potential in disc galaxies. They form naturally as a gas response to non-axisymmetry in the gravitational potential, even if the degree of this asymmetry is very small.…
Nuclear spirals are ubiquitous in galaxy centers. They exist not only in strong barred galaxies but also in galaxies without noticeable bars. We use high-resolution hydrodynamic simulations to study the properties of nuclear gas spirals…
Asymmetries in galactic potentials, either self-induced, or caused by a passing companion, play an important role in global gas dynamics in galaxies. In particular, they are able to trigger gas inflow, which in turn feeds nuclear activity.…
Dynamical evolution of spiral galaxies is strongly dependent on non-axisymmetric patterns that develop from gravitational instabilities, either spontaneously or externally triggered. Some evolutionary sequences are described through which a…
Mergers between gas--rich disks and less--massive dwarf galaxies are studied using numerical simulation. As the orbit of a satellite decays through dynamical friction, the primary disk develops large-amplitude spirals in response to its…
The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers…
Spiral galaxies have most of their stellar mass in a large rotating disk, and only a modest fraction in a central spheroidal bulge. This poses a major challenge for cosmological models of galaxy formation. Galaxies form at the centre of…
How does the gas get in nuclear regions to fuel black holes? How efficient is the feedback? The different processes to cause rapid gas inflow (or outflow) in galaxy centers are reviewed. Non axisymmetries can be created or maintained by…
With a help of hydrodynamical models, we explore fundamental modes of gas flow in central parts of a galaxy potential with non-axisymmetric perturbations of various strengths. Our grid-based algorithm allows us to get a detailed picture of…
We summarize some recent results from our observational campaign to study the central regions of spiral galaxies of late Hubble type (Scd - Sm). These disk-dominated, bulgeless galaxies have an apparently uneventful merger history. The…
The inner regions of barred galaxies contain substructures such as off-axis shocks, nuclear rings, and nuclear spirals. These substructure may affect star formation, and control the activity of a central black hole (BH) by determining the…
The central regions of galaxies show the presence of massive black holes and/or dense stellar systems. The question about their modes of formation is still under debate. A likely explanation of the formation of the central dense stellar…
We have performed smoothed particle hydrodynamics (SPH) simulations to study the response of the central kiloparsec region of a gaseous disk to the imposition of nonaxisymmetric bar potentials. The model galaxies are composed of the three…
Non-axisymmetric structures, such as bars and spiral arms, are known to concentrate molecular gas and star formation in galaxy centers, actively building up the pseudo-bulges. However, a direct link between the neutral (i.e., molecular and…
Nuclear Clusters (NCs) are common stellar systems in the centres of galaxies. Yet, the physical mechanisms involved in their formation are still debated. Using a parsec-resolution hydrodynamical simulation of a dwarf galaxy, we propose an…
Nuclear spirals can provide a wealth of information about the nuclear potential in disc galaxies. They are unlikely to form in nuclei with solid-body rotation, yet they are present in a majority of galactic centres. Their morphology varies…
In this paper, I mention a few processes which may play a role in the evolution of the central regions of galaxies. In this context, I briefly discuss some issues regarding the formation of bulges in spirals, the role of supermassive black…
Massive star formation in the central regions of spiral galaxies plays an important role in the dynamical and secular evolution of their hosts. Here, we summarise a number of recent investigations of the star formation history and the…