Related papers: A Joint GMRT/X-ray study of galaxy groups

Galaxy groups are not scaled down versions of massive galaxy clusters - the hot gas in groups (known as the intragroup medium, IGrM for short) is, on average, less dense than the intracluster medium, implying that one or more…

We present a galaxy evolution model which incorporates a physically motivated implementation of AGN feedback. Intermittent jets inflate cocoons of radio plasma which then expand supersonically, shock heating the ambient gas. The model…

We examine the hypothesis that mergers and close encounters between galaxies can fuel AGNs by increasing the rate at which gas accretes towards the central black hole. We compare the clustering of galaxies around radio-loud AGNs with the…

We have used GADGET2 to simulate the formation of an elliptical galaxy in a cosmological dark matter halo with mass 3x10^12M_Sun/h. Using a stellar population synthesis model has allowed us to compute magnitudes, colours and surface…

The thermal plasma of galaxy clusters lost most of its information on how structure formation proceeded as a result of dissipative processes. In contrast, non-equilibrium distributions of cosmic rays (CR) preserve the information about…

Radio emission from X-ray binary systems (XRBs) has developed in recent years from being peculiar phenomenon to being recognised as an ubiquitous property of several classes of XRBs. In this scenario the synchrotron emission is interpreted…

Active galactic nucleus (AGN) feedback is a key ingredient in galaxy evolution, yet its impact on the cold atomic gas reservoir -- the neutral hydrogen (HI) phase -- remains poorly constrained. We present the most extensive spatially…

We present a study of the radio properties of the dominant early-type galaxies in 26 galaxy groups, the high-richness sub-sample of the Complete Local-volume Groups Sample (CLoGS). Combining new 610 MHz and 235 MHz observations of 21 groups…

[Abridged] To understand the role of the galaxy group environment on galaxy evolution, we present a study of radio luminosity functions (RLFs) of group galaxies based on the VLA-COSMOS 3 GHz Large Project. The radio-selected sample of 7826…

We have recently shown that X-ray observations of the population of `low-excitation' radio galaxies, which includes most low-power, Fanaroff-Riley class I sources as well as some more powerful Fanaroff-Riley class II objects, are consistent…

We present the first deep low frequency radio observations of the massive and highly disturbed galaxy cluster Abell 2744 using the upgraded Giant Metrewave Radio Telescope (uGMRT). The cluster is experiencing a very complex multiple merger…

Radio mini-halos are perplexing features, typically hosted by X-ray cool-core galaxy clusters. Understanding the connection between thermal X-ray and non-thermal radio emission is key to uncovering their origin. Here, we present a…

The connection between the thermal and non-thermal properties in galaxy clusters hosting radio halos seems fairly well established. However, a comprehensive analysis of such a connection has been made only for integrated quantities (e.g.…

We review current understanding of the population of radio galaxies and radio-loud quasars from an observational perspective, focusing on their large-scale structures and dynamics. We discuss the physical conditions in radio galaxies, their…

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…

We performed GMRT low frequency observations of the radio halos, relics and new candidates belonging to the GMRT Radio Halo Cluster Sample first observed at 610 MHz. High sensitivity imaging was performed using the GMRT at 325 MHz and 240…

Expanding X-ray cavities observed in hot gas atmospheres of many galaxy groups and clusters generate shock waves and turbulence that are primary heating mechanisms required to avoid uninhibited radiatively cooling flows which are not…

We investigate the 1.4 GHz radio properties of 92 nearby (z<0.05) ultra hard X-ray selected Active Galactic Nuclei (AGN) from the Swift Burst Alert Telescope (BAT) sample. Through the ultra hard X-ray selection we minimise the biases…

Large-scale cosmological simulations suggest that feedback from active galactic nuclei (AGN) plays a crucial role in galaxy evolution. In this study, we directly test this hypothesis utilising SDSS spectra of a sample of 48 low redshift…

Isolated compact groups of galaxies (CGs) present a range of dynamical states, group velocity dispersions, and galaxy morphologies with which to study galaxy evolution, particularly the properties of gas both within the galaxies and in the…