Conveners
AGN I
- Hartmut Winkler (University of Johannesburg)
The Event Horizon Telescope (EHT) is a millimeter VLBI array observing supermassive black holes. Its 2017 observing run led to the first images of a black hole shadow in M87, in total intensity and later in polarization as well. These data and images have allowed us to conduct a black hole mass measurement and a null hypothesis test of general relativity, and to put significant constraints on...
The transformational science enabled by the Event Horizon Telescope (EHT) observations of M87* has opened a new paradigm wherein imaging the accretion and jet flows around supermassive black holes has become feasible. We embark on this potential of the EHT by constructing a sample of nearby AGNs whose immediate environment around the black hole will be explored at a high angular resolution. In...
The Event Horizon Telescope (EHT) is a global very long baseline interferometry (VLBI) network imaging supermassive black holes at horizon scales at millimetre wavelengths. In this talk, I will present an overview of the first polarised-light images of the black hole at the heart of the M87 galaxy, and the constraints they impose on the structure of the magnetic fields near the black hole. I...
It is now widely accepted that the evolution of galaxies and the growth of the central supermassive black hole (SMBH) are intimately connected. Those SMBH which are active (AGN) have been shown to influence the host galaxy and its evolution through various feedback mechanisms. This makes understanding the abundance of AGN within distant galaxies a cornerstone in current galaxy evolution...
We present results of Fermi-Large Area Telescope (LAT) light curve (LC) modelling of selected blazars. All objects have densely sampled and long-term LCs. For each blazar we generated three LCs with 7, 10, and 14 days binning, using the latest 4FGL catalogue and binned analysis provided within the fermipy package. The LCs were modelled with several tools: the Fourier transformation, the...
Blazars are a radio-loud subclass of AGN with relativistic jets closely aligned with our line of sight. The jet-emission in blazars is highly Doppler-boosted and non-thermal emission can be seen across the entire electromagnetic spectrum. These sources are highly variable across all timescales and display rapid flares across multiple wavelength bands. Blazar spectral energy distributions...
The radio through optical-UV/X-ray emission from blazars is dominated by highly polarised synchrotron emission from relativistic jet electrons. The total degree of polarisation is determined by the polarised non-thermal synchrotron emission and thermal unpolarised emission components from the dusty torus, host galaxy, emission lines from the broad line region (BLR) and accretion disk. The...
