Speakers
Description
The LOFAR International Telescope serves as an exceptionally powerful instrument for conducting thorough surveys of the sky at extremely low frequencies. Despite the extensive research on the evolution of Active Galactic Nuclei (AGNs), many aspects of this process remain elusive. Existing evolutionary models, derived from numerous observations, suggest that Gigahertz Peak Spectrum (GPS) and Compact Steep Spectrum (CSS) sources serve as precursors to large-scale radio galaxies of the FRI/FRII type. As these compact sources evolve, their radio jets endeavor to extend beyond their host galaxies, developing into large-scale structures. However, statistical analyses have uncovered a significant surplus of small, low-luminosity sources compared to powerful, fully developed, luminous radio galaxies. This suggests that not all GPS and CSS sources can evolve into large-scale structures; some exhibit intermittent, recurrent activity over periods of several thousand years.
Through the application of Very Long Baseline Interferometry (VLBI) techniques and extensive multi-epoch, multi-frequency observations, we have been able to detect even the faintest objects, acquiring their luminosities and fast-evolving spectra. These spectra serve as primary evidence of rapid changes occurring within young AGNs. Additionally, extensive scattered emission surrounding the source may serve as another indication of such phenomena, representing remnants of previous phases of activity where jet propagation was hindered and dispersed on smaller scales.
Access to the sky at extremely low frequencies, facilitated by instruments like LOFAR, now enables us to capture relic emissions, providing a unique opportunity to study the life cycle of radio sources, even on smaller scales.
However, imaging these objects necessitates substantial computational resources and time. In our work, we aim to present the results of our initial attempts to image these objects in pursuit of the aforementioned emissions, leveraging the latest available software in collaboration with the Poznań Supercomputing and Networking Center.
