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 able to resolve the hot spots in most sources. In this paper we present measurements of the radio properties of these components. The prominences of the je...

We have conducted a deep radio survey with the Very Large Array at 1.4 GHz of a region containing the Hubble Deep Field. This survey overlaps previous observations at 8.5 GHz allowing us to investigate the radio spectral properties of microjansky sources to flux densities greater than 40 μJy at 1.4 GHz and greater than 8 μJy at 8.5 GHz. A total of 371 sources have been catalogued at 1.4 GHz as ...

In this paper we present a statistical study of the environments of 49 galaxies in which there is gasor stellarcounterrotation. The number of possible companions in the field (to apparent magnitude 22), their size and concentration were considered. All the statistical parameters were analysed by means of Kolgomorov-Smirnov tests, using a control sample of 43 galaxies without counterrotation. Fr...

We consider the Fundamental Plane of elliptical galaxies lensed by the gravitational field of a massive deflector (typically, a cluster of galaxies). We show that the Fundamental Plane relation provides a straightforward measurement of the projected mass distribution of the lens with a typical accuracy of ≈ 0.15 in the dimensionless column density κ. The proposed technique breaks the mass-sheet...

We present a conformal gravity fit to the 20 largest of a sample of 110 spiral galaxies. We identify the presence of a universal quadratic potential V(κ)(r)=-κc²r²/2 with κ=9.54×10⁻⁵⁴ cm⁻² induced by cosmic inhomogeneities. When V(κ)(r) is taken in conjunction with both a universal linear potential V(γ₀)(r)=γ₀c²r/2 with γ₀=3.06×10⁻³⁰ cm⁻¹ generated by the homogeneous cosmic background and the c...

Recent studies have shown that massive quiescent galaxies at high redshift are much more compact than present-day galaxies of the same mass. Here we compare the radial stellar density profiles and the number density of a sample of massive galaxies at z ∼ 2.3 to nearby massive elliptical galaxies. We confirm that the average stellar densities of the z ∼ 2.3 galaxies within the effective radius, ...

We present deep images of the redshift z = 0.41 galaxy cluster Abell 851 (Cl 0939+4713) including a narrow bandwidth image of the redshifted [OII] λλ3726, 29 line emission. The [OII] doublet is the most accessible tracer of star formation out to redshifts near unity, and we use it to identify candidates for star-forming galaxies. The galaxies selected lie within a projected clustercentric dista...

The size distributions of 2D and 3D Voronoi cells and of cells of V p(2, 3),—2D cut of 3D Voronoi diagram—are explored, with the single-parameter (re-scaled) gamma distribution playing a central role in the analytical fitting. Observational evidence for a cellular universe is briefly reviewed. A simulated Vp(2, 3) map with galaxies lying on the cell boundaries is constructed to compare, as rega...

Results from the modelling of bars in nearly 300 galaxies are used to test predictions from theoretical work on the evolution of bars. Correlations are found between bar ellipticity and boxiness, between bar strength and normalised size, between the normalised sizes of bars and bulges, and between normalised bar size and bulge-to-total ratio. Bars with different ellipticities follow parallel li...

We investigate the properties of the B-band Tully-Fisher (T-F) relation for 25 compact group galaxies, using Vmax derived from 2-D velocity maps. Our main result is that the majority of the Hickson Compact Group galaxies lie on the T-F relation. However, about 20% of the galaxies, including the lowest-mass systems, have higher B luminosities for a given mass, or alternatively, a mass which is t...