相关论文: Bent-Double Radio Sources as Probes of Intergalact…

Radio galaxies with bent jets are predominantly located in groups and clusters of galaxies. We use bent-double radio sources, under the assumption that their jets are bent by ram-pressure, to probe intragroup medium (IGM) gas densities in…

Galaxy groups likely contain a significant fraction of the total baryonic mass in the local universe within their intragroup medium (IGM). However, aside from a handful of UV absorption line and X-ray observations, almost nothing is known…

Bent-double radio sources have been used as a probe to measure the density of intergalactic gas in galaxy groups. We carry out a series of high-resolution, 3D simulations of AGN jets moving through an external medium with a constant density…

The cocoons surrounding powerful radio sources can be extensive if the jet that feeds the cocoon is light and supersonic. They have been shown to remain overpressured with respect to the ambient medium for most of the life time of the…

Over 80% of the cosmic baryon density is likely to be distributed in the diffuse, $\gtrsim10^{4}$ K circum- and inter-galactic medium (CGM and IGM respectively). We demonstrate that the dispersion measures (DMs) of samples of localized Fast…

The radio properties of powerful extended radio sources may be used to estimate the ambient gas density in the vicinity of radio lobes. A sample of 27 radio lobes from 14 radio galaxies and of 14 radio lobes from 8 radio loud quasars was…

We are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas…

Interstellar thermal pressures can be measured using C I absorption lines that probe the pressure-sensitive populations of the fine-structure levels of its ground state. In a survey of C I absorption toward Galactic hot stars, Jenkins &…

We investigate the possibility of measuring intergalactic magnetic fields using the dispersion measures and rotation measures of fast radio bursts. With Bayesian methods, we produce probability density functions for values of these…

X-ray emission traces the gaseous environments of radio sources. The medium must be present for jet confinement, but what are its influence on jet fuelling, dynamics, propagation, and disruption? The observational situation is both…

Context: Fast radio bursts are transient radio pulses of extragalactic origin. Their dispersion measure is indicative of the baryon content in the ionized intergalactic medium between the source and the observer. However, inference using…

The warm-hot intergalactic medium (warm-hot IGM, or WHIM) pervades the filaments of the Cosmic Web and harbours half of the Universe's baryons. The WHIM's thermodynamic properties are notoriously hard to measure. Here we estimate a galaxy…

Double-lobed radio galaxies (DLRGs) often have radio lobes which subtend an angle of less than 180 degrees, and these bent DLRGs have been shown to associate preferentially with galaxy clusters and groups. In this study, we utilize a…

We have carried out optical spectroscopy with the Anglo-Australian Telescope for 24,726 objects surrounding a sample of 19 Giant Radio Galaxies (GRGs) selected to have redshifts in the range 0.05 to 0.15 and projected linear sizes from 0.8…

Galaxies and groups of galaxies exist in dark-matter halos filled with diffuse gas. The diffuse gas represents up to 80\% of the mass in baryonic matter within the halos(1,2), but is difficult to detect because of its low density (particle…

A definite prediction from recent N-body/hydro simulations of the structure formation of the universe is the presence of a diffuse intergalactic medium (IGM) in a temperature range of 10^5 - 10^7 K. This hot phase of the IGM may account for…

We review some of the ways that X-ray observations provide unique information on radio galaxies. Thermal bremsstrahlung X-ray emission provides detailed data on ambient densities and temperatures. These parameters in turn can be used for…

We studied bent radio sources within X-ray galaxy groups in the COSMOS and XMM-LSS fields, using radio data from the MeerKAT International GHz Tiered Extragalactic Explorations data release 1 (MIGHTEE-DR1) at 1.2-1.3 GHz (angular…

A sample of 20 powerful extended radio galaxies with redshifts between zero and two were used to determine constraints on global cosmological parameters. Data for six radio sources were obtained from the VLA archive, analyzed, and combined…

Context. Studies on compact galaxy groups have led to the conclusion that a plenitude of phenomena take place in between galaxies that form them. However, radio data on these objects are extremely scarce and not much is known concerning the…