Stellar Hearts and Cosmic Echoes: Gravitational-Wave Progenitors Through Cosmic Time

When stars end their lives, their hearts continue to exist in a different, exotic form, known as a compact remnant: black holes, neutron stars, or white dwarfs. Understanding the exact origin of these objects is one of the most pressing scientific questions in astrophysics at this time. With the discovery of gravitational waves (GWs), we now have a new way to study these extreme objects, but also several new puzzles to solve, such as the origin of the large number of high-mass binary black hole mergers. To make breakthroughs in understanding the properties of stellar remnants and the GWs they generate, it is crucial to study the binary stellar hearts that form them.In this PhD project we will use numerical simulations to constrain the physics of stellar hearts in binary systems. In particular, we will research how the structures of binary stellar hearts change as a function of metallicity, and investigate whether their final properties can explain the origin of recently-discovered high-mass black holes. Based on these results, we will predict the properties of GW sources that will be observable with next-generation detectors such as the Einstein Telescope.

Keywords:massive stars, gravitational-wave progenitors, Black holes

Disciplines:Stellar astrophysics, Gravitational radiation astrophysics

Project type:PhD project