Modelling and detection of polarized gravitational waves from a supernova

Core-collapse supernovae play a central role in the evolution of massive stars, the formation of neutron stars and black holes, and the chemical enrichment of galaxies.

The explosion mechanism can be probed through the analysis of multi-messenger signals, particularly neutrinos and gravitational waves, whose properties are modulated by hydrodynamic instabilities in the seconds following the formation of the proto-compact neutron star.

This project (Q1) aims to exploit the complementarity of multi-messenger signals from a core-collapse supernova, in connection with numerical simulations of collapse dynamics and perturbative analyses, in order to extract physical constraints on the explosion mechanism. The study will focus on the multi-messenger signatures of the standing accretion shock instability (SASI) and the corotational instability (low T/W) in rotating progenitors, analyzing in particular neutrino composition, gravitational wave polarization, and correlations between these signals.

Before starting his PhD, Alphonse Moreau participated in the LIGO–Virgo–KAGRA workshop on supernovae and developed an analytical model of the interaction between acoustic waves and internal gravity waves, characterizing the associated energy transfer. A close collaboration with AIM, APC, and the Melbourne group now provides him access to numerical simulations to analyze gravitational wave and neutrino signatures of these instabilities.

This project’s principal investigator is Thierry Foglizzo (AIM, CEA).