Related papers: The Arches Cluster: Extended Structure and Tidal R…
Galaxy physical properties are influenced by their environments, but the processes responsible for mass and environmental quenching and structural transformations remain debated. Galaxy clusters are ideal laboratories for investigating…
The location of a galaxy cluster's centroid is typically derived from observations of the galactic and/or gas component of the cluster, but these typically deviate from the true centre. This can produce bias when observations are combined…
Context. Extratidal stars are stellar bodies that end up outside the tidal radius of a cluster as a result of internal processes or external forces acting upon it. The presence and spatial distribution of these stars can give us insights…
The three young clusters in the Galactic Center represent the closest examples of massive starbursts and they define the upper mass limit of the Galactic cluster mass functions. In this review, I describe the characteristics and content of…
To study the strength and structure of the magnetic field in the Galactic centre (GC) we measured Faraday rotation of the radio emission of pulsars which are seen towards the GC. Three of these pulsars have the largest rotation measures…
The outskirts of galaxy clusters host complex interactions between the intra-cluster and circumcluster media. During cluster evolution, ram-pressure stripped gas clumps from infalling substructures break the uniformity of the gas…
We present new Hubble Space Telescope imaging of the outer regions of M87 in order to study its globular cluster (GC) population out to large galactocentric distances. We discuss particularly the relationship between GC effective radii…
The census of massive clusters of galaxies in the local Universe is almost complete, thanks to their prominent observational signatures at X-ray, optical, and sub-mm wavelengths. Nevertheless, a number of such systems are likely to be…
The Galactic Center hosts a rotating disk of young stars between 0.05 and 0.5 pc of Sgr A*. The ``S-stars'' at a distance $<0.04$ pc, however, are on eccentric orbits with nearly isotropically distributed inclinations. The dynamical origin…
We present preliminary results of the first near-infrared variability study of the Arches cluster, using adaptive optics data from NIRI/Gemini and NACO/VLT. The goal is to discover eclipsing binaries in this young (2.5 $\pm$ 0.5 Myr),…
The Triangulum Spiral Galaxy Messier 33 offers unique insights into the building of a galactic disk. We identify spectacular arcs of intermediate age (0.6 Gyr - 2 Gyr) stars in the low-metallicity outer disk. The northern arc spans approx.…
We report the discovery of a previously unknown massive Galactic star cluster at l=29.22, b=-0.20. Identified visually in mid-IR images from the Spitzer GLIMPSE survey, the cluster contains at least 8 late-type supergiants, based on…
In the present work we investigate the properties of 18 embedded clusters (ECs). The sample includes 11 previously known clusters and we report the discovery of 7 ECs on WISE images, thus complementing our recent list of 437 new clusters.…
There is no accepted upper mass limit for stars. Such a basic quantity escapes both theory, because of incomplete understanding of star formation, and observation, because of incompleteness in surveying the Galaxy. The Arches cluster is…
We investigated the formation of arc-like structures in the infalling envelope around protostars, motivated by the recent Atacama Large Millimeter/Submillimeter Array (ALMA) observations of the high-density molecular cloud core,…
We present the discovery of four remote star clusters in M33, one of which is of an extended nature. Three of the clusters were discovered using survey data from the Isaac Newton Telescope Wide-Field Camera while one was discovered…
We derive structural parameters for ~2000 globular clusters in the giant Virgo elliptical M87 using extremely deep Hubble Space Telescope images in F606W (V) and F814W (I) taken with the ACS/WFC. The cluster scale sizes (half-light radii…
The Perseus complex offers an ideal testbed to study cluster formation and early evolution as it hosts two major hierarchical structures (namely LISCA I and LISCA II) and the W3/W4/W5 (W345) region characterized by recent star formation.…
We present here the results of a detailed study of the X-ray properties of the cluster of galaxies Abell 3128 (z=0.06), based on the analysis of deep (100 ks) XMM-Newton data. The most obvious feature of the X-ray morphology of A3128 is the…
The environmental dependencies of the characteristics of spiral galaxy rotation curves are studied in this work. We use our large, homogeneously collected sample of 510 cluster spiral galaxy rotation curves to test the claim that the shape…