ngVLAKey Science Goal 4: Fundamental Physics with Galactic Center Pulsars
Abstract
Pulsars in the Galactic Center (GC) are important probes of General Relativity, star formation, stellar dynamics, stellar evolution, the interstellar medium, and the supermassive black hole accretion flow. In particular, a pulsar in orbit around the GC black hole, Sgr A*, will provide an unprecedented probe of black hole physics and General Relativity, measuring black hole mass, spin, and quadrupole moment, and testing the Kerr metric at sensitivities orders of magnitude better than any other method. The rich recent star formation history and abundant population of high mass stars indicate that thousands of pulsars should be present in the GC. After years of searching, however, only a small number of pulsars in the central tens of parsecs are known. Most important among these is the GC magnetar, the first pulsar found to orbit a supermassive black hole; it has provided the community with an unprecedented tool for characterizing the environment and population of GC pulsars, which points toward the need for high sensitivity observations at radio frequencies up to 30 GHz. These capabilities are necessary to overcome the competing effects of strong interstellar scattering, bright GC background, and steep pulsar spectra, creating for the first time the opportunity to discover millisecond pulsars and pulsars in short-period binaries, as well as survey the full population of slow pulsars. The Next Generation Very Large Array is a design and development project of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.
- Publication:
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American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23536421B