Monthly Meeting December –

This month two University of Auckland PHD students will tell us about their research,

Observing Transients in Simulated Universes with Max Briel and Gravitational Waves with Petra Tang

Observing Transients in Simulated Universes

Transients are short, on an astronomical timescale, duration events compared to the evolution of galaxies and
stars. Two main types are gravitational wave (GW) events and supernovae. Supernovae, explosion at the end of a
stars life, have been measured for centuries, but gravitational waves from the merger of two compact objects,
were only measured for the first time in 2015. The rate of both of these events relate to the amount of stars being
formed over the history of the Universe and the evolution of binary star systems. Using stellar population synthesis
and cosmological simulation of the Universe, we predict the number of transients taking place in our Universe.

Born and raised in the Netherlands, Max Briel studied physics, maths, and computer science as part of his Liberal
Arts and Sciences Bachelor, which he was awarded with highest honours in 2013. As part of the neutrino detection
collaboration, he finished his Masters at the University of Amsterdam in Physics and Astronomy with a research
project on muonic event reconstruction in the KM3NeT detector. Since 2020 he’s a PhD student at the University of
Auckland. There, he works on the properties of gravitational wave and supernovae’s host galaxies.

Gravitational Waves

Gravitational waves propagate through space and carry information about the history of our Universe, helping us
understand the unknown part of the Universe. The Laser Interferometer Space Antenna (LISA) is a gravitational
wave observatory in space, and it is used to detect the milihertz band of the GW signals. In her research Petra re-
constructs the spectral density of the stochastic gravitational wave background of mock LISA signals, hoping to
identify LISA’s detection capability. In this talk she introduces LISA’s unique setup, explains the method she uses to
construct the spectrum profile, presents some of her results and explains the next step for her PhD

Petra Tang is a current PhD student studying gravitational waves. She did her Masters at the University of Auckland
supervised by AP Jan Eldridge. Prior to that she taught Maths in a secondary school for 6 years. She loves science
and education, and loves sharing her knowledge of the stars with others.