Related papers: FRII radio galaxies with z<0.3 -- II. Beaming and …
In previous papers we have discussed high-resolution observations of a large sample of powerful radio galaxies with z<0.3. Jets are detected in up to 80 per cent of the sample, and radio cores in nearly all the objects; in addition, we are…
In a long-term observing project we have imaged a complete sample of FRII quasars and radio galaxies with z < 1.0 at high resolution and high sensitivity with the VLA and MERLIN. This sample of 98 sources includes 15 quasars, 11 broad line…
This paper focuses on two aspects of the Physics of Radio Galaxies in which it has been proposed that relativistic beaming of radiation is necessary to account for the observations. Physical arguments are presented which show that it is…
The idea that Fanaroff-Riley Class~I Radio Galaxies contain core jets with Lorentz factors of the order of a few and are the parent population for BL~Lac Objects is examined, with particular reference to the data on two FRI Radio Galaxies,…
We explore the viability of the unification of BL Lacs and FR I radio galaxies by comparing the core emission of radio galaxies with those of BL Lacs of similar extended radio power, taking advantage of the newly measured optical nuclear…
Radio jet and core data for a complete sample of 98 FRII sources with z < 1 are analysed with a Markov-Chain Monte Carlo (MCMC) model fitting method to obtain constraints on bulk-flow speeds in the beam. The Bayesian parameter-inference…
We explore the viability of the unification of BL Lacs and FR I radio galaxies by comparing the core emission of radio galaxies with those of BL Lacs, taking advantage of the newly measured optical nuclear luminosity of FR I sources. The…
We model the kiloparsec-scale synchrotron emission from jets in 10 Fanaroff-Riley Class I radio galaxies for which we have sensitive, high-resolution imaging and polarimetry from the Very Large Array. We assume that the jets are…
Active galaxies are the most powerful engines in the Universe for converting gravitational energy into radiation, and their study at all epochs of evolution is therefore important. Powerful radio-loud quasars and radio galaxies have the…
We address the question of whether or not the properties of all low-luminosity flat spectrum radio sources, not just the obvious BL Lac objects, are consistent with them being the relativistically beamed counterparts of the low radio…
We model jets in low-luminosity (FR I) radio galaxies as intrinsically symmetrical, axisymmetric, decelerating relativistic flows with transverse velocity gradients. This allows us to derive velocity fields and the three-dimensional…
We perform three-dimensional numerical simulations of relativistic (with a Lorentz factor of 10), non magnetized jets propagating in a uniform density environment, in order to study the effect of the entrainment and the consequent…
We present the first large sample investigation of the properties of jets in Fanaroff and Riley type I radio galaxies (FR-I) based on data from the Chandra archive. We explore relations between the properties of the jets and the properties…
We present a sample of 30 wide angle tailed radio galaxies (WATs) that we use to constrain the jet speeds in these sources. We measure the distribution of jet-sidedness ratios for the sample, and assuming that the jets are beamed, jet…
We summarise the recent progress of a project to determine physical conditions in the jets of low-luminosity (FR I) radio galaxies. We model the jets as intrinsically symmetrical, relativistic, decelerating flows. By fitting to deep,…
An asymmetric relativistic model for FRII radio sources is described which takes account of both relativistic effects and intrinsic/environmental asymmetries to explain the observed structural asymmetry of their radio lobes. A key feature…
Recently, Owen(1993) and Owen and Ledlow (1994) have shown that the dividing line between Fanaroff-Riley class~I and class~II Radio Sources is very sharp when the sources are represented as points in the radio-optical luminosity plane. It…
Radio galaxies are classified into two primary categories based on their morphology: center-brightened FR-I and edge-brightened FR-II. It is believed that the jet power and interactions with the ambient medium govern the deceleration and…
We examine the optical properties of the nuclei of low luminosity radio-galaxies using snapshot HST images of the B2 sample. In agreement with the results obtained from the analysis of the brighter 3C/FRI sample, we find a correlation…
There is now unequivocal evidence that the jets in FR I radio galaxies are initially relativistic, decelerating flows. On the assumption that they are axisymmetric and intrinsically symmetrical (a good approximation close to the nucleus),…