Related papers: Demonstration of KVN phase referencing capability

We present an updated K band (24 GHz) celestial reference frame (CRF) constructed from 3.5 million Very Long Baseline Interferometry (VLBI) observations collected during 211 observing epochs between May 2002 and December 2025 using the Very…

We present 5 GHz e-MERLIN observations of the GOODS-N region at sub-arcsec resolution (0.2--0.5 arcsec). These data form part of the early commissioning observations for the e-MERLIN interferometer and a pilot for the e-MERLIN legacy…

Over the past few decades, our knowledge of jets produced by active galactic nuclei (AGN) has greatly progressed thanks to the development of very-long-baseline interferometry (VLBI). Nevertheless, the crucial mechanisms involved in the…

The largest Key Science Program of the RadioAstron space VLBI mission is a survey of active galactic nuclei (AGN). The main goal of the survey is to measure and study the brightness of AGN cores in order to better understand the physics of…

We are now exploring the inner region of Type 1 active galactic nuclei (AGNs) with the Keck interferometer in the near-infrared. Adding to the four targets previously studied, we report measurements of the K-band (2.2 um) visibilities for…

We present the first near-infrared K-band long-baseline interferometric measurement of the prototype Seyfert 2 galaxy NGC 1068 with resolution lambda/B \~ 10 mas obtained with the Very Large Telescope Interferometer (VLTI) and the two 8.2m…

Radio galaxies are relatively faint at $\gamma$-ray energies, where they make up only 1-2% of all AGN detected by Fermi-LAT. However, they offer a unique perspective to study the intrinsic properties of AGN jets. For this reason, the…

Radio-loud active galactic nuclei (AGN) with their jets pointed close to our line of sight constitute the majority of extragalactic $\gamma$-ray sources and significantly contribute to the radiation observed in the even higher energy…

The NGVS-IR project (Next Generation Virgo Survey - Infrared) is a contiguous near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). The current state of NGVS-IR consists…

We utilized the Edelson and Malkan (2012) and Stern et al. (2012) selection techniques and other methods to identify AGN candidates that were monitored during the Kepler prime and K2 missions. Subsequent to those observations, we obtained…

Active Galactic Nuclei (AGN) are ideal sources for multi-wavelength studies as their emission can cover almost 20 orders of magnitude in frequency from the radio to the gamma-ray band. After reviewing their basic properties, I will assess…

We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…

We present initial results from the 4.8 GHz Very Long Baseline Array (VLBA) survey of the JWST North Ecliptic Pole Time-Domain Field (TDF). From 106 radio sources found in the Karl G. Jansky Very Large Array observations in the TDF, we…

The Seyfert 2 galaxy NGC3079 is one of the nearest radio-weak AGN. We have carried out multi-frequency, multi-epoch VLBI observations of this object and detected new components, proper motion of the order of 0.1 c, strong spectral…

We present a statistical study of several fundamental properties of radio sources in nearby clusters, including the radial distribution within clusters, the radio luminosity function (RLF), and the fraction of galaxies that is radio-active…

The analysis of the variability of active galactic nuclei (AGNs) at different wavelengths and the study of possible correlations among different spectral windows are nowadays a major field of inquiry. Optical variability has been largely…

We present deep, wide-field European VLBI Network (EVN) 1.6 GHz observations of the Hubble Deep Field (HDF) region with a resolution of 0.025 arcseconds. Above the 210 microJy/beam (5sigma) detection level, the EVN clearly detects two radio…

We present the type-1 active galactic nuclei (AGN) sample extracted from the VIMOS VLT Deep Survey first observations of 21000 spectra in 1.75 square degree. This sample, which is purely magnitude limited, free of morphological or color…

We present 115 compact radio point sources in three galaxies, NGC 5474, NGC 4631 and M51, taken in the most extended (A-)configuration of the Karl G. Jansky Very Large Array at 10GHz. Several of these compact radio point sources have…

Some microquasars are permanently bright radio sources while others are faint but produce powerful radio outbursts. Most of the X-ray binaries (XRB) however are very faint or undetected in the radio regime. The European VLBI Network (EVN)…