Searches for Galactic Center Pulsars and Radio Observations of the Galactic Center Magnetar PSR J1745–2900

The discovery of new pulsars in tight orbits around the supermassive black hole at the Galactic Center (GC) would allow for unprecedented tests of fundamental physics and theories of gravity, including General Relativity, in an unexplored strong-field regime of gravity. To date, six pulsars have been detected within the central 0.5°, which include an ultra-rare magnetar, PSR J1745–2900, with a projected separation of ~0.1 pc from Sgr A*. The other five known GC pulsars are believed to lie in the foreground, despite their close angular separation from Sgr A*. Although the GC magnetar is the closest known pulsar to Sgr A*, its orbit with the central black hole is not sufficiently short to observe relativistic effects.

We are currently carrying out high frequency radio observations of the GC using the NASA Deep Space Network 70-m radio antenna, DSS-43, in Canberra, Australia. We will discuss new results from a study of radio pulses from the GC magnetar. The magnetar's pulses consist of multiple emission components, some of which show changes on very fast timescales and significant evidence of pulse broadening. Frequency structure is also observed in many of the magnetar's pulse components. Lastly, we will give an overview of our current work towards detecting new GC pulsars.