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VLA FRAMEx. III. Circumnuclear Radio Emission Mechanisms in Hard X-ray Selected Active Galactic Nuclei
Andrew J. Sargent, Alexander J. van der Horst, Megan C. Johnson +5
We present Stokes I continuum analysis for a volume-limited sample () of hard X-ray selected active galactic nuclei (AGNs) using GHz observations with the Karl…
VLA FRAMEx. II. Radio Spectra of Nearby Active Galactic Nuclei at Subarcsecond Resolution
Andrew J. Sargent, Alexander J. van der Horst, Megan C. Johnson +5
We present GHz in-band spectral energy distributions with accompanying 6 GHz and 10 GHz imaging results for a volume-complete sample ( Mpc) of hard X-ray selected activ…
FRAMEx. V. Radio Spectral Shape at Central Sub-parsec Region of AGNs
Onic I. Shuvo, Megan C. Johnson, Nathan J. Secrest +4
We present results from the Very Long Baseline Array (VLBA) multi-frequency (1.6, 4.4, 8.6, 22 GHz), high-sensitivity (~25 microJy beam^-1), sub-parsec scale (<1 pc) observations a…
VLA FRAMEx. I. Wideband Radio Properties of the AGN in NGC 4388
Andrew J. Sargent, Travis C. Fischer, Megan C. Johnson +5
We present the first results from Karl G. Jansky Very Large Array (VLA) observations as a part of the Fundamental Reference Active Galactic Nucleus (AGN) Monitoring Experiment (FRA…
Dissecting the interstellar medium of a z=6.3 galaxy: X-shooter spectroscopy and HST imaging of the afterglow and environment of the Swift GRB 210905A
A. Saccardi, S. D. Vergani, A. De Cia +35
The study of the properties of galaxies in the first billion years after the Big Bang is one of the major topic of current astrophysics. Optical/near-infrared spectroscopy of the a…
Wandering Black Hole Candidates in Dwarf Galaxies at VLBI Resolution
Andrew J. Sargent, Megan C. Johnson, Amy E. Reines +5
Thirteen dwarf galaxies have recently been found to host radio-selected accreting massive black hole (MBH) candidates, some of which are ``wandering" in the outskirts of their host…
Sub-arcsecond imaging with the International LOFAR Telescope: II. Completion of the LOFAR Long-Baseline Calibrator Survey
Neal Jackson, Shruti Badole, John Morgan +69
The Low-Frequency Array (LOFAR) Long-Baseline Calibrator Survey (LBCS) was conducted between 2014 and 2019 in order to obtain a set of suitable calibrators for the LOFAR array. In…
LOFAR imaging of Cygnus A -- Direct detection of a turnover in the hotspot radio spectra
J. P. McKean, L. E. H. Godfrey, S. Vegetti +75
The low-frequency radio spectra of the hotspots within powerful radio galaxies can provide valuable information about the physical processes operating at the site of the jet termin…
LOFAR MSSS: Discovery of a 2.56 Mpc giant radio galaxy associated with a disturbed galaxy group
A. O. Clarke, G. Heald, T. Jarrett +40
We report on the discovery in the LOFAR Multifrequency Snapshot Sky Survey (MSSS) of a giant radio galaxy (GRG) with a projected size of Mpc projected on the sky. I…
Wide-field LOFAR imaging of the field around the double-double radio galaxy B1834+620: A fresh view on a restarted AGN and doubeltjes
E. Orrú, S. van Velzen, R. F. Pizzo +8
The existence of double-double radio galaxies (DDRGs) is evidence for recurrent jet activity in AGN, as expected from standard accretion models. A detailed study of these rare sour…
GRB 080517: A local, low luminosity GRB in a dusty galaxy at z=0.09
E. R. Stanway, A. J. Levan, N. R. Tanvir +4
We present an analysis of the photometry and spectroscopy of the host galaxy of Swift-detected GRB 080517. From our optical spectroscopy, we identify a redshift of z = 0.089 +/- 0.…
Initial LOFAR observations of Epoch of Reionization windows: II. Diffuse polarized emission in the ELAIS-N1 field
V. Jelic, A. G. de Bruyn, M. Mevius +106
This study aims to characterise the polarized foreground emission in the ELAIS-N1 field and to address its possible implications for the extraction of the cosmological 21-cm signal…
High-Time-Resolution Measurements of the Polarization of the Crab Pulsar at 1.38 GHz
Agnieszka Slowikowska, Benjamin W. Stappers, Alice K. Harding +4
Using the Westerbork Synthesis Radio Telescope (WSRT), we obtained high-time-resolution measurements of the full (linear and circular) polarization of the Crab pulsar. Taken at a r…
Discovery of Carbon Radio Recombination Lines in absorption towards Cygnus~A
J. B. R. Oonk, R. J. van Weeren, F. Salgado +100
We present the first detection of carbon radio recombination line absorption along the line of sight to Cygnus A. The observations were carried out with the LOw Frequency ARray in…