Conveners
AGN/ High-z
- Pratik Dabhade (Instituto de Astrofísica de Canarias (IAC, Spain))
AGN/ High-z
- Konstantinos Kolokythas (Rhodes University)
New radio continuum surveys - and in particular those at low frequencies - have given the opportunity to expand the selection and characterisation of remnant and restarted radio AGN. This is crucial in order to learn more about the life-cycle of these objects and relate it to AGN feedback.
I will present the latest results that we have obtained making use of images from LOFAR 150 MHz, which...
Ultra Steep Spectrum (USS) radio sources have been successfully used to select powerful radio galaxies at high redshifts. Typically restricted to large-sky surveys and relatively bright radio flux densities, it has gradually become possible to extend the USS search to new sensitivity levels, thanks to a new generation of radio surveys produced by the so-called SKA-pathfinders. Combining recent...
Most massive galaxies are now thought to go through an Active Galactic Nucleus (AGN) phase one or more times. Yet, the cause of triggering and the variations in the intrinsic and observed properties of the AGN population are still poorly understood. Young, compact radio sources associated with accreting supermassive black holes represent an essential phase in the life cycles of jetted AGN for...
The LOFAR Two-meter Sky Survey is the largest extragalactic survey to date. As part of the final stages of our third generation interferometric data reduction pipeline, we have synthetized ~480.000 dynamic spectra in full polarisation in the direction of about 85.000 nearby stellar objects (including exoplanetary systems). I propose to present the main results from a preliminary statistical...
he second data release of the LOFAR Two-Metre Sky Survey (LoTSS)
covers 27% of the northern sky, with a total area of ∼ 5,700 deg$^2$. We
have used a combination of automatic cross-matching, citizen science,
and expert visual inspection to find optical identifications for
around 3.5 million radio sources in the survey, generating by far the
largest catalogue of identified radio sources...
The advent of long-baseline interferometers such as the LOw-Frequency Array (LOFAR) telescope enables high angular resolution and sensitivity, which is crucial for understanding synchrotron emission processes and the low-frequency spectral behaviour of radio-loud active galactic nuclei (RLAGN). Using the large RLAGN sample constructed from the LOFAR Two-metre Sky Survey (LoTSS) first data...
Double-double radio galaxies (DDRGs) are key evidence of recurrent AGN activity, featuring two pairs of radio lobes, typically along a similar axis. These DDRGs, often displaying FR-II morphology, exhibit differences between their outer, diffuse lobes from earlier activity cycles and their more recent, hotspot-rich lobes. Variations in the restarting timescale or environmental inhomogeneities...
Early results from the LOFAR Two-Metre Sky Survey (LoTSS) revealed that radio AGN are prevalent in local massive galaxies, with all those above a stellar mass of $10^{11} M_{\odot}$ being switched on at radio wavelengths. Inference-based jet modelling for LoTSS radio AGN then showed that the integrated power output of the population is sufficient to counterbalance X-ray radiative cooling...
