We present the first near-infrared (K′-band) homogeneous observations of a complete sub-sample of the 3CR radio catalogue comprising all High Excitation Galaxies (HEGs) at z <0.3. After showing that the surface brightness decomposition technique to measure central point-like sources is affected by significant uncertainties for the objects in the studied sample, we present a new, more accurate m...

IceCube is a km scale neutrino detector being constructed deep in the Antarctic ice. When complete, IceCube will consist of 4800 optical modules deployed on 80 strings between 1450 and 2450 m of depth. During the 2007-2008 data taking season, 22 strings were operational. This configuration is already much larger than previous neutrino telescopes and provides better sensitivity to point sources ...

In September 2005, the observing program of the Whipple 10 m gamma-ray telescope was redefined to be dedicated almost exclusively to AGN monitoring. Since then the five Northern Hemisphere blazars that had already been detected at Whipple are monitored routinely each night that they are visible. Thanks to the efforts of a large number of multiwavelength collaborators, the first year of this pro...

The simple unification scheme of powerful radio galaxies and quasars, based entirely on the orientation dependent effects, has been confronted with the observed radio structures for 152 radio galaxies and 173 steep spectrum quasars. Contrary to the scheme's prediction, the cosmological evolution of geometrical parameters describing the large scale structure of these two types of radio sources a...

We present Hubble Space Telescope Imaging Spectrograph long-slit spectroscopy of the emission line nebulae in the compact steep spectrum radio sources 3C 67, 3C 277.1, and 3C 303.1. We derive BPT (Baldwin-Philips-Terlevich; Baldwin et al. 1981) diagnostic emission line ratios for the nebulae which are consistent with a mix of shock excitation and photo-ionization in the extended gas. In additio...

Using NICMOS on HST, we have imaged the emission-line nebulae and the line-free continuum in 4C 40.36, a ultra-steep spectrum FR II radio galaxy at z = 2.269. The line-free continuum was found to be extremely compact and symmetric while the emission-line nebulae seen in Ho+[N II] show very clumpy structures spreading almost linearly over 16 kpc. However, this linear structure is clearly misalig...

Feedback driven by jets from active galactic nuclei is believed to be responsible for reducing cooling flows in cool-core galaxy clusters. We use simulations model feedback hydrodynamic isolated halos. While the jet propagation converges only after diameter of well resolved, reliable predictions about effects these have on time distribution function require resolutions sufficient keep jet-infla...

Hubble Space Telescope revealed a dicothomy in the central surface brightness profiles of early-type galaxies, that subsequently have been grouped into two families: core, boxy, anisotropic systems and cuspy (”power law”), disky, rotating ones. Here we investigate whether a dicothomy is present also in the X-ray properties of the two families. We consider both their total soft emission (LSX,tot...

Globular clusters in galaxies have a mutual feedback with the environment, which is tuned by their dynamical evolution. This feedback may be the explanation of various features of both the globular cluster system and the host galaxy. Relevant examples of these are the radial distribution of globulars and the violent initial activity of galaxies as AGN.

Relativistic outflows represent one of the best-suited tools to probe the physics of AGN. Numerical modelling of internal structure of the relativistic outflows on parsec scales provides important clues about the conditions and dynamics of the material in the immediate vicinity of the central black holes in AGN.