The Parkes Pulsar Timing Array Third Data Release: Overview and Search for an Isotropic Gravitational-wave Background

Explore the Parkes Pulsar Timing Array (PPTA) Third Data Release and its search for an isotropic gravitational-wave background in this comprehensive 54-minute conference talk. Delve into the project's primary aim of detecting nanohertz-frequency gravitational waves using CSIRO's Parkes Radio Telescope, Murriyang. Examine the high-precision pulsar timing observations spanning 18 years, including data from the new Ultra-wide Bandwidth Low Receiver. Learn about the single-pulsar noise analysis employing physically-motivated models to account for variations in pulse times of arrival. Discover the results of the search for an isotropic stochastic gravitational-wave background (GWB), including the recovery of a common-spectrum noise process among pulsars and its characteristic amplitude. Investigate the hierarchical Bayesian search for inter-pulsar correlations and its consistency with Hellings-Downs correlations expected from an isotropic GWB. Analyze the apparent time-dependency of the signal strength and its implications. Gain insights into these findings within the context of historical and contemporary analyses in the field of gravitational wave detection.