Related papers: NGC 3627: a galaxy-dwarf collision?
Deep X-ray data from CHANDRA and XMM-Newton, and GMRT radio data are presented for ZwCl 2341.1+0000, an extremely unusual and complex merging cluster of galaxies at the intersection of optical filaments. We propose that energetics of…
We present deep near-infrared images, taken with Subaru Telescope, of the region around the z=1.08 radio source 3C 356 which show it to be associated with a poor cluster of galaxies. We discuss evidence that this cluster comprises two…
A hot phase of the interstellar medium has now been detected and studied in several objects through its X-ray emission. A proper assessment of its characteristics is relevant for our understanding of several aspects of galaxy properties,…
Ram pressure stripping of galactic gas is generally assumed to be inefficient in galaxy groups due to the relatively low density of the intragroup medium and the small velocity dispersions of groups. To test this assumption, we obtained…
Here we present detailed analysis of the distinct X-ray emission features present within the Eastern radio lobe of the Pictor A galaxy, around the jet termination region, utilising the data obtained from the Chandra X-ray Observatory.…
Our situation as occupants of the Milky Way (MW) Galaxy, bombarded by the Sagittarius dwarf galaxy, provides an intimate view of physical processes that can lead to the dynamical heating of a galactic disc. While this evolution is…
We present a deep high-resolution Chandra X-ray Observatory image data of a powerful compact radio source PKS 0023-26 associated with a quasar at redshift 0.322. The earlier studies of the optical environment suggested that the source could…
UGCA 320 is a gas-rich dwarf irregular galaxy which belongs to a nearby, relatively isolated group of dwarf galaxies. Here, we combine multi-band HST imaging data with deep long-slit SALT/RSS and integral-field VLT/MUSE spectral data to…
As a major cooling line of interstellar gas, the far-infrared 158 {\mu}m line from singly ionised carbon [CII] is an important tracer of various components of the interstellar medium in galaxies across all spatial and morphological scales.…
We report the detection of a pair of dwarf galaxies at $z\!=\!0.30$ which may be in the early stages of an interaction. Both galaxies have stellar masses of $<10^{9}M_\odot$, and display a projected separation of $\sim\!29$kpc and a…
We present a Chandra X-ray observation that shows, unambiguously for the first time, the presence of a giant diffuse X-ray-emitting corona around the edge-on disk galaxy NGC 4631. This corona, with a characteristic thermal temperature of…
We present models of interacting galaxies in order to study the development of spatial offsets between the gaseous and stellar components in tidal tails. Observationally, such offsets are observed to exist over large scales (e.g., NGC 3690;…
Two lines of evidence indicate that active galaxies, principally radio galaxies, have heated the diffuse hot gas in clusters. The first is the general need for additional heating to explain the steepness of the X-ray luminosity--temperature…
Two dwarf irregular galaxies DDO 187 and NGC 3738 exhibit a striking pattern of star formation: intense star formation is taking place in a large region occupying roughly half of the inner part of the optical galaxy. We use data on the HI…
The analysis of a deep (579 ks) Chandra ACIS pointing of the elliptical galaxy NGC4278, which hosts a low luminosity AGN and compact radio emission, allowed us to detect extended emission from hot gas out to a radius of \sim 5 kpc, with a…
The X-ray emission in many clusters of galaxies shows a central peak in surface brightness coincident with a drop in temperature. These characterize a cooling flow. There is often a radio source also at the centre of such regions. Data from…
We compare a very deep X-ray image of M87, at the center of the Virgo Cluster, to high-quality optical images of the low excitation emission-line gas in the same region. There are striking coincidences of detail between the two. We explore…
We investigate the origin of the variation of the gas mass fraction in the core of galaxy clusters, which was indicated by our work on the X-ray fundamental plane. The adopted model supposes that the gas distribution characterized by the…
We present new important results about the intermediate-type Seyfert galaxy Mrk 315, recently observed through optical imaging and integral-field spectroscopy. Broad-band images were used to study the morphology of the host galaxy,…
The pair of large radio lobes in the Virgo cluster, each about 23 kpc in radius, have curiously sharp outer edges where the radio-synchrotron continuum flux declines abruptly. However, just adjacent to this sharp transition, the radio flux…