Related papers: The Relation between Nuclear Activity and Stellar …
It is now widely believed that the growth of massive black holes is closely linked to the formation of galaxies, but there have been few concrete constraints on the actual physical processes responsible for this coupling. Investigating the…
The relationship of an AGN to its host galaxy is a crucial question in the study of galaxy evolution. We perform stellar population synthesis in the central regions of galaxies of different activity levels. A large number of stellar…
Nuclear activity in galaxies is closely connected to galactic mergers and supermassive black holes (SBH). Galactic mergers perturb substantially the dynamics of gas and stellar population in the merging galaxies, and they are expected to…
Although it is clear that the circumnuclear regions of galaxies are intimately related to their host galaxies, most directly through their bars, it remains unclear what exactly initiates and fuels nuclear stellar (starburst) and non-stellar…
Motivated by the apparently conflicting results reported in the literature on the effect of environment on nuclear activity, we have carried out a new analysis by comparing the fraction of galaxies hosting active galactic nuclei (AGNs) in…
There is considerable evidence that the circumnuclear regions of galaxies are intimately related to their host galaxies, most directly through their bars. There is also convincing evidence for relations between the properties of…
The issue of a starburst-AGN connection in local and distant galaxies is relevant for understanding galaxy formation and evolution, the star formation and metal enrichment history of the universe, the origin of the extragalactic background…
We use a complete sample of galaxies drawn from the SDSS to study how structure, star formation and nuclear activity depend on local density and on stellar mass. Local density is estimated by counting galaxies above a fixed absolute…
The role of stars and starbursts in AGN has been a recurring issue for nearly as long as AGN have been recognized as hosts of interesting phenomena. The heated ``starburst X monster'' controversy of the 80's and 90's was gradually replaced…
We study galaxies that host both nuclear star clusters and active galactic nuclei (AGN) implying the presence of a massive black hole. We select a sample of 176 galaxies with previously detected nuclear star clusters that range from…
The physical quantities that directly regulate AGN feedback in massive galaxies remain poorly understood. Observations of molecular gas surrounding AGNs suggest that this gas serves as a fuel source for AGN activity. Accordingly, we study…
The main requirements for fueling an active galactic nucleus and to form massive black holes are reviewed. Low-luminosity AGN can be fueled easily from the local star clusters, near the nucleus, and the various stellar processes are…
To understand the physical origin of the close connection between supermassive black holes and their host galaxies, it is vital to investigate star formation properties in active galaxies. Using a large dataset of nearby type 1 active…
In order to study whether there is any correlation between nuclear activities, gas content, and the environment where galaxies reside, we have obtained optical and millimetric spectra for a well-defined sample of intermediate Hubble type…
It has always been believed that feedback from active galactic nuclei (AGN) has an important impact on star formation in massive galaxies. Black hole spin is an important physical parameter of AGN. We use a large sample of massive…
It has long been known that galaxy interactions are associated with enhanced star formation. In a companion paper, we explored this connection by applying a variety of statistics to SDSS data. In particular, we showed that specific star…
We study the environmental effects on the activity in galactic nuclei by comparing galaxies in clusters and in the field. Using a spectroscopic sample of galaxies in Abell clusters from the SDSS DR7, we investigate the dependence of nuclear…
Galaxy mass and environment play a major role in the evolution of galaxies. In the transition from star-forming to quenched galaxies, Active galactic nuclei (AGN) have also a principal action. However, the connections between these three…
Scaling relations between galactic parameters represent key pieces of evidence for investigating the processes of galaxy formation and evolution. In most studies, these relations have been obtained for large portions of the galaxies (i.e.,…
Nuclear stellar clusters are a common phenomenon in spirals and in starbursts galaxies, and they may be a natural consequence of the star formation processes in the central regions of galaxies. HST UV imaging of a few Seyfert 2 galaxies…