Related papers: Is Centaurus A special? A neutral hydrogen perspec…

The origin of ultrahigh energy cosmic rays (UHECRs) is an open question. In this proceeding, we first review the general physical requirements that a source must meet for acceleration to 10-100 EeV, including the consideration that the…

Centaurus A, the cosmic ray accelerator a few Mpc away from us is possibly one of the nearest sources of extremely high energy cosmic rays. We investigate whether the gamma ray data currently available from Centaurus A in the GeV-TeV energy…

We report observations at mid-infrared and sub-millimeter wavelengths of Centaurus A (CenA, NGC 5128), the giant elliptical galaxy that harbors the closest radio loud Active Galactic Nucleus (AGN) to Earth. The dust emission from the deep…

We present UBVJHKHalpha and HI data of the irregular galaxy NGC 2366. It is a normal boxy-shaped disk seen at high inclination angle. We do not see any unambiguous observational signature of a bar. There is an asymmetrical extension of…

The Pierre Auger collaboration has reported a correlation between Ultra-High Energy Cosmic Rays (UHECR) and nearby Active Galactic Nuclei (AGNs) within 75 Mpc. Two of these events fall within 3 degrees from Centaurus A, the nearest AGN,…

This paper is the second in a series presenting a sample of 29 late-type dwarf galaxies observed with the Westerbork Synthesis Radio Telescope in the 21-cm line of neutral hydrogen (HI). Here we present rotation curves, maps of the velocity…

We present Australia Telescope Compact Array radio data of the dwarf irregular galaxy ESO 324-G024 which is seen in projection against the giant, northern lobe of the radio galaxy Centaurus A (Cen A, NGC 5128). The distorted morphology and…

HI absorption studies yield information on both AGN feeding and feedback processes. This AGN activity interacts with the neutral gas in compact radio sources, which are believed to represent the young or recently re-triggered AGN…

In the coming decade, thousands of stellar streams will be observed in the halos of external galaxies. What fundamental discoveries will we make about dark matter from these streams? As a first attempt to look at these questions, we model…

Based on recent results obtained by the Pierre Auger Observatory (PAO), it has been hypothesized that Centaurus A (Cen A) is a source of ultra-high-energy cosmic rays (UHECRs) and associated neutrinos. We point out that the diffuse neutrino…

One of the most important problems in the study of active galaxies is understanding the detailed geometry, physics, and evolution of the central engines and their environments. The leading models involve an accretion disk and torus…

We present detailed image analysis of rest-frame optical images of 235 low-redshift ($z \leq$ 0.35) type 1 active galactic nuclei (AGNs) observed with the Hubble Space Telescope. The high-resolution images enable us to perform rigorous…

Although a strong similarity between radio galaxies and Seyferts has been pointed out with ASCA, some radio galaxies do not seem to fit very well the cold thin accretion disk model proposed for radio quiet AGN. The BeppoSAX observations of…

Images covering the central 450 by 100 arcsecond (about 8.0 by 2.0 kpc) of NGC 5128 (Centaurus A) obtained using SCUBA at 850 and 450 micron with beam sizes of 14.5 and 8 arcsecond respectively, are presented. These data are compared with…

We report the results of interferometric observations of Centaurus A with the MID-infrared Interferometer (MIDI) at ESO's VLTI telescope array. The interferometric measurements are spectrally resolved (R = 30) in the wavelength range 8 to…

We present HI line and 20-cm radio continuum observations of the NGC 1511 galaxy group obtained with the Australia Telescope Compact Array. The data reveal an extended, rather disturbed HI distribution for the peculiar starburst galaxy NGC…

We study a sample of 5 dwarf irregular galaxies in the CenA/M83 group, which are companions to the giant elliptical CenA. We aim at deriving their physical properties over their lifetime and compare them to those of dwarfs located in…

We study the multi-phase medium in the vicinity of the active galactic nucleus Centaurus A (Cen A). Combined high-resolution observations with the ALMA and Chandra observatories indicate that the hot X-ray emitting plasma coexists with the…

We present measurements obtained with the Spitzer Space Telescope in five bands from 3.6-24 microns of the northern inner radio lobe of Centaurus A, the nearest powerful radio galaxy. We show that this emission is synchrotron in origin.…

At less than 4 Mpc distance the radio galaxy NGC 5128 (Centaurus A) is the prime example to study the supermassive black hole and its influence on the environment in great detail. To model and understand the feeding and feedback mechanisms…