CGCA Seminar – Matt Miles

Galaxy-Scale Gravitational Wave Detection: The MPTA and the Road Ahead

Dr. Matt Miles
Vanderbilt University

Gravitational waves are emitted across a vast spectrum of frequencies. Ground-based detectors such as LIGO/Virgo/KAGRA observe relatively high-frequency waves from compact object mergers, while at the other end of the spectrum, the inspirals of supermassive black hole binaries produce a low-frequency rumble detectable only with a galaxy-scale instrument. By monitoring the pulses emitted by millisecond pulsars distributed across the Milky Way, pulsar timing arrays construct such a detector, spanning thousands of light-years. In recent years, multiple pulsar timing array collaborations have reported mounting evidence for a gravitational wave background permeating the galaxy, and the international effort to combine data across these experiments is well underway. In this talk, I will describe how pulsar timing arrays operate, what we have found so far — with a focus on the MeerKAT Pulsar Timing Array, which exploits one of the world’s most sensitive radio telescopes — and the road ahead. I will also discuss new tools and techniques being developed to push the frontiers of pulsar timing, including faster and more accessible timing software, methods that exploit the full information content of pulse profiles rather than collapsing them to single arrival times, and novel approaches to measuring pulsar distances using gravitational wave signals themselves.