Related papers: SCG0018-4854: a young and dynamic compact group I.…
We present an analysis of the ellipticities of galaxy groups, derived from the spatial distribution of member galaxies, revealing a notable incongruity between the observed local galaxy groups and their counterparts in the Lambda cold dark…
Using the WiFeS integral field spectrograph, we have undertaken a series of observations of star-forming galaxies in Compact Groups. In this first paper dedicated to the project, we present the analysis of the spiral galaxy NGC838, a member…
Encounters between galaxies modify their morphology, kinematics, and star formation (SF) history. The relation between these changes and external perturbations is not straightforward. The great number of parameters involved requires both…
Interaction between galaxies play a pivotal role in their evolution. Ongoing star formation in spiral galaxies can be affected by these processes. We select a sample of interacting galaxies in field environments at various interaction…
We discuss the structure, galaxy content and kinematics of a sparse, probably collapsing group around IC 65 and an evolved rich group around NGC 6962
We examine the star clusters in the irregular galaxy NGC 4449. We use a near-infrared spectrum and broad-band images taken with the HST to place a limit of 8--15 Myrs on the age of the bright central ojbect in NGC 4449. Its luminosity and…
We study the formation and the evolution of galaxy groups in a critical universe, showing the importance of secondary infall for their dynamical evolution. Merging is only slightly accelerated if galaxies have massive halos, because the…
Multi-wavelength observations of Hickson's Compact Groups (HCGs) have shown that many of these groups are physical bound structures and are in different stage of evolution, from spiral-dominated systems to almost merged objects. Very few…
While most galaxies live in group environments where they undergo an accelerated evolution, the characteristics of their circumgalactic medium (CGM) remain uncertain. We present an analysis of the CGM of two galaxy groups in different…
We use CANUCS JWST/NIRCam imaging of galaxies behind the gravitationally-lensing cluster MACS J0417.5-1154 to investigate star formation burstiness in low-mass ($M_\star\sim10^8\ M_\odot$) galaxies at $z\sim4.7-6.5$. Our sample of 123…
We present an investigation of galaxy-galaxy interactions and their effects on the velocity fields of disc galaxies in combined N-body/hydrodynamic simulations, which include cooling, star formation with feedback, and galactic winds.…
Compact groups (CGs) of galaxies offer an exceptional laboratory for the study of dense galaxian environments --- where interactions, tidally induced activity, and mergers are expected to be at their highest rate of occurrence. Here, we…
Massive halos of hot plasma exist around some, but not all elliptical galaxies. There is evidence that this is related to the age of the galaxy. In this paper new X-ray observations are presented for three early-type galaxies that show…
Interactions between galaxies have spectacular effects on gas dynamics, and small galaxy groups are a privileged place to investigate them. In particular, they could test the existence of cold H2 gas as dark matter in the outer parts of…
The transformation and evolution of a galaxy is strongly influenced by interactions with its environment. Neutral hydrogen (\HI) is an excellent way to trace these interactions. Here, we present \HI\ observations of the spiral galaxy…
The study of galaxy groups is essential to understanding the evolutionary history of large-scale structures in the Universe. These dense environments have a significant impact on galaxy evolution, influencing their gas content, morphology,…
In this second paper of two analyses, we present near-infrared (NIR) morphological and asymmetry studies performed in sample of 92 galaxies found in different density environments: galaxies in Compact Groups (HCGs), Isolated Pairs of…
This is the first paper of a series on the investigation of stellar population properties and galaxy evolution of an observationally homogeneous sample of early-type galaxies in groups, field and isolated galaxies. We present high S/N…
We have studied stellar and gaseous kinematics as well as stellar population properties in the center of the early-type barred galaxy NGC 4245 by means of integral-field spectroscopy. We have found a chemically distinct compact core, more…
We studied the nearby edge-on galaxy NGC4656 and its dwarf low surface brightness companion with the enhanced UV brightness, NGC4656UV, belonging to the interacting system NGC4631/56. Regular photometric structure and relatively big size of…