TAP Colloquium

Monday, Dec 9, 2013
4:00 pm — 5:00 pm

Location: Kuiper Space Sciences
Room: 308

Jason Dexter
University of California, Berkeley

Exploring Strong Gravity in the Galactic Center
The center of the Milky Way is an excellent laboratory for understanding star formation and black hole feeding and feedback in a normal galactic nucleus. In addition, the Galactic center black hole, Sgr A*, provides a remarkable opportunity to study strong gravity. Very long baseline interferometry observations at millimeter wavelengths are now spatially resolving event horizon scales around Sgr A*. This Event Horizon Telescope experiment may detect the black hole "shadow," and near-infrared astrometry with the VLTI instrument GRAVITY will achieve similar resolution in the next few years. In both cases, interpreting the data requires physical modeling. I will discuss the construction of relativistic emission models from numerical simulations of black hole accretion flows and jets, what we've learned from their comparison with current data, and the prospects for detecting signatures of strong gravity in future observations. Pulsars orbiting Sgr A* could provide additional, independent tests of general relativity. I will argue that the recent discovery of the first detection of a pulsar close to Sgr A*, a rare magnetar outburst, implies the presence of an unusual pulsar population in the Galactic center.
TAP Colloquia