Core-collapse supernova neutrino emission and detection informed by state-of-the-art three-dimensional numerical models

TL;DR

This study uses advanced 3D supernova models to analyze neutrino signals, revealing the effects of PNS convection, asymmetries, and instabilities on detectability and spectra in multiple observatories.

Contribution

It introduces a comprehensive 3D simulation-based analysis of supernova neutrino signals, highlighting new insights into signal variations, asymmetries, and a novel spectrum reconstruction technique.

Findings

Neutrino signals differ mainly due to PNS convection.

Detectable time variations linked to spiral SASI in non-exploding models.

New spectrum reconstruction method estimates neutrino energy spectra within 20% error for nearby supernovae.

Abstract

Based on our recent three-dimensional core-collapse supernova (CCSN) simulations including both exploding and non-exploding models, we study the detailed neutrino signals in representative terrestrial neutrino observatories, Super-Kamiokande (Hyper-Kamiokande), DUNE, JUNO, and IceCube. We find that the physical origin of difference in the neutrino signals between 1D and 3D is mainly proto-neutron-star (PNS) convection. We study the temporal and angular variations of the neutrino signals and discuss the detectability of the time variations driven by the spiral Standing Accretion Shock Instability (spiral SASI) when it emerges for non-exploding models. In addition, we determine that there can be a large angular asymmetry in the event rate ($\gtrsim 50 \%$), but that the time-integrated signal has a relatively modest asymmetry ($\lesssim 20 \%$). Both features are associated with the lepton-number emission self-sustained asymmetry (LESA) and the spiral SASI. Moreover, our analysis suggests that there is an interesting correlation between the total neutrino energy (TONE) and the cumulative number of neutrino events in each detector, a correlation that can facilitate data analyses of real observations. We demonstrate the retrieval of neutrino energy spectra for all flavors of neutrino by applying a novel spectrum reconstruction technique to the data from multiple detectors. We find that this new method is capable of estimating the TONE within the error of $\sim$20\% if the distance to the CCSN is $\lesssim 6$ kpc.