Gravitational-Wave Signals for Supernova Explosions of Three-Dimensional Progenitors

TL;DR

This paper analyzes gravitational wave signals from 3D core-collapse supernova models, highlighting the impact of progenitor asymmetries and discussing detection prospects with current and future interferometers.

Contribution

It presents the first 3D supernova simulations starting from progenitors with detailed pre-collapse asymmetries, exploring their influence on GW signals.

Findings

GW signals originate from known dynamical phenomena like convection and shock instabilities.

No new GW features directly linked to pre-collapse progenitor activity were identified.

Galactic supernova GW signals are detectable with existing and upcoming interferometers.

Abstract

Core-collapse supernovae (SNe) are sources of gravitational waves (GWs) produced by hydrodynamical instabilities and highly time-dependent anisotropies of the neutrino radiation. In this work we analyze both contributions to the GW signal for two state-of-the-art three-dimensional (3D) SN models computed with the Prometheus-Vertex neutrino-hydrodynamics code. In contrast to the far majority of models analyzed for GWs so far, our core-collapse simulations were started with 12.28 M_sun (18.88 M_sun) progenitors, whose final hour (7 min) of convective oxygen-shell burning was computed in 3D and featured a vigorous oxygen-neon shell merger. The corresponding large-scale asymmetries in the oxygen layer are conducive to buoyancy-aided neutrino-driven explosions. The models were continuously evolved in 3D from the pre-collapse evolution until 5.11 s (1.68 s) after the core bounce. The GW signals result from the well-known dynamical phenomena in the SN core such as prompt postshock convection, neutrino-driven convection, the standing accretion shock instability, proto-neutron star oscillations, and anisotropic ejecta expansion. They do not exhibit any new or specific features that can be unambiguously connected to the powerful pre-collapse activity in the progenitors, but we identify interesting differences compared to results in the literature. We also discuss measurement prospects by interferometers, confirming that GW signals from future Galactic SNe will be detectable with existing and next-generation experiments working in the frequency range f ~ 1-2000 Hz.