Related papers: Co-evolution of Nuclear Rings, Bars and the Centra…
We present analysis of 63 nearby ($<$ 44 Mpc) early-type galaxies hosting nuclear star clusters using the recently discovered parameter Central Intensity Ratio (CIR$_I$) determined from near-infra-red (3.6 $\mu$m) observations with the…
We present correlations involving central intensity ratio (CIR) of 52 early type galaxies, including 24 ellipticals and 28 lenticulars, selected from low density environment in the nearby (< 30 Mpc) universe. CIR is found to be negatively…
We report strong connections between central intensity ratio (CIR) and hot gas properties of Early-type galaxies (ETGs) in the nearby ($\rm D<30 Mpc$) Universe. We find new strong correlations between (optical) CIR and X-ray gas luminosity…
We use the recently discovered simple photometric parameter Central Intensity Ratio (CIR, Aswathy & Ravikumar 2018) determined for a sample of 57 nearby (z < 0.02) Seyfert galaxies to explore the central features of galaxies and their…
We propose a novel technique to estimate the masses of super massive black holes (SMBHs) residing at the centres of massive galaxies in the nearby Universe using simple photometry. Aperture photometry using SEXTRACTOR is employed to…
Nuclear rings are excellent laboratories for probing diverse phenomena such as the formation and evolution of young massive star clusters (YMCs), nuclear starbursts, as well as the secular evolution and dynamics of their host galaxies. We…
We have analyzed the frequency and properties of the nuclear activity in a sample of galaxies with circumnuclear rings and spirals (CNRs). This sample was compared with a control sample of galaxies with very similar global properties but…
We present optical broad- and narrow-band imaging of a sample of a dozen barred galaxies. These images are analyzed in conjunction with our previously published near-infrared imaging of their central regions and with literature values for,…
We present results from a photometric H-alpha survey of 22 nuclear rings, aiming to provide insight into their star formation properties, including age distribution, dynamical timescales, star formation rates, and galactic bar influence. We…
We have analyzed the frequency and properties of the nuclear activity in a sample of galaxies with circumnuclear rings and spirals (CNRs). This sample was compared with a control sample of galaxies with very similar global properties but…
We explore the near-infrared (NIR) $K$-band properties of galaxies within 93 galaxy clusters and groups using data from the 2MASS. We use X-ray properties of these clusters to pinpoint cluster centers and estimate cluster masses. By…
Secular evolution gradually shapes galaxies by internal processes, in contrast to early cosmological evolution which is more rapid. An important driver of secular evolution is the flow of gas from the disk into the central regions, often…
Aims: We present a statistical analysis of different characteristics of ringed spiral galaxies with the aim of assessing the effects of rings on disk galaxy properties. Methods: We built a catalog of ringed galaxies from the Sloan Digital…
We explore extreme mass-ratio inspirals (EMRIs) in the co-evolution of massive black holes (MBHs) and nuclear star clusters (NSCs), which host diverse stellar populations across a wide range of masses. The dynamics are simulated…
The centres of disc galaxies host a variety of structures built via both internal and external processes. In this study, we constrain the formation and evolution of these central structures, in particular nuclear rings and nuclear discs, by…
We present a detailed study of the bar fraction in the CfA sample of Seyfert galaxies, and in a carefully selected control sample of non-active galaxies, to investigate the relation between the presence of bars and of nuclear activity. To…
We investigate the structural properties of nuclear star clusters in late-type spiral galaxies. More specifically, we fit analytical models to HST images of 39 nuclear clusters in order to determine their effective radii after correction…
Recent observations with the Hubble Space Telescope (HST) have revealed that a large fraction of late-type (Sc and later) spiral galaxies harbor a bright, compact stellar cluster in their dynamical centers. Statistics of the mass, age, and…
Context: The morphology of massive star formation in the central regions of galaxies is an important tracer of the dynamical processes that govern the evolution of disk, bulge, and nuclear activity. Aims: We present optical imaging of the…
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…