Related papers: Key Science Observations of AGNs with KaVA Array

We present the results of very long baseline interferometry (VLBI) observations of gamma-ray bright blazar S5 0716+714 using the Korean VLBI Network (KVN) at the 22, 43, 86, and 129 GHz bands, as part of the Interferometric Monitoring of…

The giant radio galaxy M 87, with its proximity (16 Mpc) and its very massive black hole ((3 - 6) \times 10^9 M_solar), provides a unique laboratory to investigate very high energy (E>100 GeV; VHE) gamma-ray emission from active galactic…

With the advent of GRAVITY+, the upgrade to the beam combiner GRAVITY at the Very Large Telescope Interferometer (VLTI), fainter and higher redshift active galactic nuclei (AGNs) are becoming observable, opening an unprecedented opportunity…

We present the results of Very Long Baseline Interferometry (VLBI) observations using the phase reference technique to detect weak Active Galactic Nuclei (AGN) cores in the Virgo cluster. Our observations were carried out using the Korean…

We discuss the case for using the Next Generation Very Large Array both to discover new black hole X-ray binaries astrometrically, and to characterize them. We anticipate that the ngVLA will be able to find $\sim$100 new black hole X-ray…

Detailed studies of relativistic jets in active galactic nuclei (AGN) require high-fidelity imaging at the highest possible resolution. This can be achieved using very long baseline interferometry (VLBI) at radio frequencies, combining…

We report on a novel search for radio gravitational lenses. Using the Very Large Array, we imaged ten candidates with both dual redshifts in Sloan Digital Sky Survey spectra and 1.4 GHz radio flux >2 mJy in the FIRST survey. The VLA maps…

We present the first results from the Fundamental Reference AGN Monitoring Experiment (FRAMEx), an observational campaign dedicated to understanding the physical processes that affect the apparent positions and morphologies of AGNs. In this…

The galaxy M87 is one of the prime targets for high resolution radio imaging to investigate the supermassive black hole, accretion flow, and relativistic jet. However, it remains challenging to observe them jointly. In 2018, GMVA+ALMA…

We present full-polarization observations at $\lambda = 0.87$ mm (345 GHz) conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) toward Messier 87 (M87) and seven other radio-loud active galactic nuclei (AGN). We determine…

We report observations of Faraday rotation measures (RMs) for a sample of 191 extragalactic radio jets observed within the MOJAVE program. Multifrequency VLBA observations were carried out over twelve epochs in 2006 at four frequencies…

Radio galaxies are the only non-blazar AGN detected in the VHE (E > 100 GeV) band. These objects enable the investigation of the main substructures of the AGN, in particular the core, the jet and its interaction with the intergalactic…

Imaging the vicinity of a black hole is one of the ultimate goals of VLBI astronomy. The closest massive black hole, Sgr A*, located at the Galactic center, is the leading candidate for such observations. Combined with recent VLBI recording…

I summarize the science drivers presented at the workshop for Phase I of the Square Kilometre Array: 'Advancing Astrophysics with the Square Kilometre Array'. I build from the historical perspective of the original Key Science programs:…

Radio observations with Very Long Baseline Interferometry (VLBI) provide the highest resolution in astronomy. Combining earth-bound with space-based telescopes and advancing the observations to mm-wavelengths increases the resolution even…

Jets associated with Active Galactic Nuclei (AGN) have been observed for almost a century, initially at optical and radio wavelengths. They are now widely accepted as "exhausts" produced electromagnetically by the central, spinning, massive…

The next-generation Very Large Array (ngVLA) is intended to be the premier centimeter-wavelength facility for astronomy and astrophysics, building on the substantial scientific legacies of the Karl G. Jansky Very Large Array (VLA) and the…

We study the kinematics of the M87 jet using the first year data of the KVN and VERA Array (KaVA) large program, which has densely monitored the jet at 22 and 43 GHz since 2016. We find that the apparent jet speeds generally increase from…

The central radio source in M87 provides the best opportunity to study jet formation because it has a large angular size for the gravitational radius of the black hole and has a bright jet that is well resolved by VLBI observations. We…

We present the first astrometry catalog from the Japanese VLBI (very long baseline interferometer) project VERA (VLBI Exploration of Radio Astrometry). We have compiled all the astrometry results from VERA, providing accurate trigonometric…