Extracting SASI signatures from Gravitational Waves of Core-Collapse Supernovae using the Hilbert-Huang Transform

TL;DR

This paper applies the Hilbert-Huang transform to 3D supernova simulations to identify SASI signatures in gravitational waves, aiding the understanding of supernova explosion mechanisms through gravitational wave and neutrino signals.

Contribution

It introduces a novel application of the Hilbert-Huang transform to extract SASI signatures from simulated gravitational wave data of supernovae.

Findings

Successfully identified SASI signatures in simulated gravitational wave data.

Demonstrated the method's effectiveness in the context of Einstein Telescope sensitivity.

Provided insights into the frequency evolution of SASI during supernova explosions.

Abstract

Core collapse supernovae are among the most energetic astrophysical events in the Universe. Despite huge efforts on understanding the main ingredients triggering such explosions, we still lack of compelling evidences for the precise mechanism driving those phenomena. They are expected to produce gravitational waves due to asymmetric mass motions in the collapsing core, and emit in the meanwhile neutrinos as a result of the interactions in their high-density environment. The combination of these two cosmic messengers can provide a unique probe to study the inner engine of these processes and unveil the explosion mechanism. Among the possible detectable signature, standing accretion shock instabilities (SASI) are particularly relevant in this context as they establish a direct connection between gravitational wave emission and the outcoming neutrino flux. In this work, Hilbert-Huang transform is applied to a selected sample of 3D numerical simulations, with the aim of identifying SASI contribution and extract its instantaneous frequency. The performance of the method is evaluated in the context of Einstein Telescope.