Illuminating the vicinity of black holes
eXtreme Gravity Institute, Montana State University
Accreting supermassive black holes, or active galactic nuclei (AGN), are amongst the most energetic sources of radiation in the Universe. In some cases, they produce more light than all of the stars in their host galaxy combined. In my webinar, I will discuss how we can use this immense amount of radiation as a probe of the properties of the black hole itself, the extreme conditions in its immediate environment and the physical processes that take place there. I will present some of my recent work on measuring the angular momentum of supermassive black holes, and explore whether its rotational energy could provide the power source for the relativistic jets that are seen in some AGN. I will conclude by discussing new results on the conditions in the black hole’s `corona’ – a region of highly energetic particles with a radiative energy density a million times that of its Solar analog. In this respect, as in many others, the vicinity of the black hole provides a unique laboratory for studying matter in extreme conditions.
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- King, A. L., Lohfink, A., & Kara, E. (2017). AGN Coronae Through A Jet Perspective. The Astrophysical Journal, 835(2), 226. doi:10.3847/1538-4357/835/2/226