Populations of pulsators: Asteroseismology and population synthesis as tools for stellar ages

Speaker: Associate Professor Simon Murphy
Affiliation: University of Southern Queensland

Abstract

The ages of stars are notoriously difficult to determine, especially for young stars that are still shrouded in dust or surrounded by discs. Here, every Myr matters, as we try to probe the processes of planet formation and stellar composition build-up. If stellar ages are biased, the knock-on effects for exoplanet characterisation are huge, affecting not just demographics, but even the detection probabilities for direct imaging searches. I discuss the various challenges in ascertaining the ages of hot, young stars, and how stellar population synthesis can help us assess whether common tools like stellar isochrones are leading us astray. I will present asteroseismology as an alternative technique capable of achieving better age precision, which approaches 10% for pre-main-sequence stars, before wrapping up with a few ideas on where this research can break new ground.

Biography

Assoc. Prof Simon Murphy is an asteroseismologist, specialising in determining the ages of intermediate mass stars. He particularly focuses on young stars, including those on the pre-main sequence. He grew up in the UK and did his undergraduate degree at The University of Manchester and obtained his PhD at the University of Central Lancashire in Preston, England, in 2013. He then spent 9 years at the University of Sydney, including as an ARC DECRA fellow. He is now an ARC Future Fellow working at the University of Southern Queensland.