654 citations · 1.8k across the 33 of their papers we have counts for
8 papers · 1 filter
The rise and fall of a binary AGN candidate: the story of PSO J334.2028+1.4075
P. Benke, S. Frey, K. É. Gabányi +7
Apparently periodic optical variations of the luminous high-redshift (z=2.06) quasar PSO J334.2028+1.4075 led Liu et al. (2015) to interpret the variability as the orbital period o…
Constraining the radio jet proper motion of the high-redshift quasar J2134-0419 at z=4.3
K. Perger, S. Frey, K. É. Gabányi +12
To date, PMN J2134-0419 (at a redshift z=4.33) is the second most distant quasar known with a milliarcsecond-scale morphology permitting direct estimates of the jet proper motion.…
Radio spectra of bright compact sources at z>4.5
Rocco Coppejans, Sjoert van Velzen, Huib T. Intema +10
High-redshift quasars are important to study galaxy and active galactic nuclei (AGN) evolution, test cosmological models, and study supermassive black hole growth. Optical searches…
VLBI observations of four radio quasars at : blazars or not?
H. -M. Cao, S. Frey, K. É. Gabányi +5
Blazars are active galactic nuclei (AGN) whose relativistic jets point nearly to the line of sight. Their compact radio structure can be imaged with very long baseline interferomet…
On the nature of bright compact radio sources at z>4.5
Rocco Coppejans, Sándor Frey, Dávid Cseh +7
High-redshift radio-loud quasars are used to, among other things, test the predictions of cosmological models, set constraints on black hole growth in the early universe and unders…
What are the megahertz peaked-spectrum sources?
Rocco Coppejans, David Cseh, Sjoert van Velzen +8
Megahertz peaked-spectrum (MPS) sources have spectra that peak at frequencies below 1 GHz in the observer's frame and are believed to be radio-loud active galactic nuclei (AGN). We…