Informazioni sull’evento

02/09/2018

Attenzione: a seguito delle disposizioni per il contenimento della diffusione del coronavirus, i seminari saranno in modalità online. Il link per il collegamento verrà reso disponibile nei giorni precedenti la data del seminario. Qui, invece, la playlist dei remote talks già messi in rete »

Joint Astrophysical Colloquium

Zooming into the heart of Centaurus A with the Event Horizon Telescope

Michael Janssen (Max-Planck-Institut für Radioastronomie, Bonn)

Thursday 30/09/2021 @ 11:30, Remote Talk

I will present the latest results from the Event Horizon Telescope (EHT): Our high resolution observations of the extragalactic radio jet of Centaurus A. Compared to the previously obtained highest resolution image of the source, we have achieved a 16x sharper frequency at a 10x higher observing frequency and are thereby able to probe the jet launching region on sub-lightday scales. We reveal a highly collimated, asymmetrically edge-brightened jet as well as the fainter counterjet. We can directly compare our image to VLBI observations of M87 at a lower frequency, as both probe the same size scales in terms of gravitational radii. Based on the similarity of these jets, we show that our observations provide further support for the fundamental plane of black hole activity in an intermediate mass regime. Based on the location of the resolved radio core in Cen A, we predict the source's black hole shadow to be visible at THz frequencies, which makes this source an interesting target for future high-frequency space VLBI missions. I will conclude with an outlook of the next observational and modeling steps for our studies of this source and other EHT targets.