Colloquium on Mar. 29, 2024

Pulsar Polarization Arrays

Speaker: Tao Liu (Hong Kong University of Science and Technology)

Venue: SWIFAR Building 2111

Time: 15:00 PM, Friday, Mar. 29, 2024

Abstract:

Pulsars are known to be extraordinary astronomical clocks and linear polarizers. As astronomical clocks, the millisecond pulsars can be used to form a galaxy-scale interferometer, known as Pulsar Timing Arrays (PTA) since 1980's, to detect nano-Hertz gravitational waves. As linear polarizers, we have proposed recently to construct Pulsar Polarization Arrays (PPA) to explore new phenomena in astrophysics and fundamental physics with a common correlated polarization signal at galaxy scale, based on the readily available polarization data accumulated over decades. In this talk, I will give an introduction to this new methodology, and as one scientific case, demonstrate its strong capability to detect ultralight axion-like wave dark matter (one of the mainstream dark matter candidates). I will also discuss the potential synergization of PPA and PTA in performing this scientific task.