The Solar System and even our own galaxy, the Milky Way are very tiny compared to the vast volume of the observable Universe. Therefore there is a huge selection of exciting research topics, astrophysical phenomena and objects potentially available for our group. Our main research interests are distant stellar explosions called supernovae, as well as tidal disruption events, gamma-ray bursts and other transient phenomena. We also study active galactic nuclei in the widest range of electromagnetic wavebands, and even by means of neutrino observations.
Important result
Studies of the most distant radio quasars with the highest resolution
Astronomical observations indicate that radio-loud active galactic nuclei (quasars) already existed in the very early Universe, less than one billion years after the Big Bang. In these, a supermassive black hole accretes material from its surroundings. A part of this material, accelerated nearly to the speed of light, leaves the system in two opposite directions along the rotation axis. The synchrotron radiation of charged particles spiraling outward along the lines of the strong magnetic field can be detected with radio telescopes. With extensive networks of such radio telescopes, the radio emitting plasma beams of quasars, the jets, can be mapped with very high resolution using interferometric (VLBI) measurements. From these data, we can infer the physical and geometric properties of the jets, the speed of the jet components, and the inclination angle of the jet with respect to the line of sight. We can determine to what extent the most distant known radio quasars are similar to quasars of later ages of the Universe and how they differ from them. In recent years, we made high-resolution VLBI images of an increasing number of rare high-redshift quasars and, using older data, we were able to measure their apparent "superluminal" motions.
VLBI radio interferometric measurements of the variations of the jet of the J2134-0419 high-redshift quasar (source: Perger et al., MNRAS, 477, 1065, 2018).
Perger K., Frey, S., Gabányi K. É et al., Constraining the radio jet proper motion of the high-redshift quasar J2134-0419 at z = 4.3, Monthly Notices of the Royal Astronomical Society, Volume 477, Issue 1, p.1065-1070, 2018,
https://ui.adsabs.harvard.edu/abs/2018MNRAS.477.1065P/abstract