The Galactic Center Pulsar
Geoffrey Bower



A pulsar in a bound orbit to the Galactic Center black hole, Sagittarius A*, provides one of the most powerful probes of general relativity. PSR J1745-2900 was discovered in Spring 2013 through an X-ray outburst and is identified as a magnetar. It is the closest pulsar to Sgr A* yet known at a projected separation of 0.1 pc. The pulsar exhibits the highest rotation measure and dispersion measure of any pulsar giving a detailed probe of the central parsec ISM and magnetic field and their connection to the accretion flow onto Sgr A*. A combination of angular and temporal broadening measurements resolves a long-standing controversy over the origin of the GC hyperstrong scattering screen. High resolution astrometry demonstrates a likely origin for the pulsar in the central stellar cluster along with a kick velocity comparable to that of ordinary pulsars. The demonstrated ability to detect pulsars in the vicinity of Sgr A* at low radio frequencies along with the appearance of a rare magnetar raises the question of whether the GC pulsar population is anomalous.