STRW local: Student Colloqia

Student Colloquia

Faint radio galaxies at the highest redshifts (PhD colloquium)

Radio galaxies are fascinating objects. Being one of the rarest types of galaxies in the early Universe, high-redshift radio galaxies are often hosted by massive galaxies that are actively building up their stellar mass through intense star formation. Since their radio emission is powered by active galactic nuclei, studying radio galaxies at high redshifts gives unique insights into the build-up of supermassive black holes and how it affects the growth of their host galaxy. In my colloquium, I will sum up my PhD work by first describing a theoretical model that tracks the origin and evolution of radio emission from these AGN at high redshifts. I will then introduce a new sample of faint radio sources selected at low radio frequencies and present follow-up spectroscopy and imaging for this sample. We find that fainter radio galaxies at high redshifts are different from the most luminous radio galaxies already known in the literature. Our faint sample also led to the discovery of the highest z radio galaxy known till date, at a redshift of 5.72, pushing studies of luminous radio sources ever closer to the epoch of reionisation.