Speaker
Heino Falcke
(Radboud University Nijmegen & ASTRON)
Description
Black holes are supposed to power the nuclei of galaxies. The best place to test this paradigm is the Galactic center. Here a compact radio source, Sgr A*, with a mass of 4 Million solar masses marks the very center of our Galaxy. Numerical magnetohydrodynamic simulations and semi-analytic models seem to converge towards a combined jet-disk model producing radiation from radio to X-rays to explain the emission. Interestingly, radio interferometry and timing observations are now probing the smallest scales of this object, directly confirming that the high-frequency radio emission indeed comes from event-horizon scales. This allows one to study basic astrophysical processes such as jet formation and accretion physics. Using future mm-VLBI experiments, involving, e.g., ALMA, it should be possible to even image the elusive event horizon of a black hole for the very first time. This “Event Horizon Telescope” turn Sgr A* into a fundamental laboratory for precision black hole astrophysics.
Author
Heino Falcke
(Radboud University Nijmegen & ASTRON)