KamLAND Sensitivity to Neutrinos from Pre-Supernova Stars

TL;DR

This paper demonstrates that the KamLAND detector can identify neutrinos from pre-supernova stars within 690 parsecs, offering early warning capabilities for imminent supernovae through neutrino detection.

Contribution

It introduces the potential of KamLAND to detect pre-supernova neutrinos, enabling early supernova alerts based on neutrino signals from massive stars nearing explosion.

Findings

KamLAND can detect pre-supernova neutrinos from a 25 solar mass star within 690 parsecs.

Detection significance depends on neutrino mass ordering and background levels.

KamLAND can provide early supernova alerts before the explosion occurs.

Abstract

In the late stages of nuclear burning for massive stars ($M>8~M_{\sun}$), the production of neutrino-antineutrino pairs through various processes becomes the dominant stellar cooling mechanism. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron anti-neutrinos exceeds the energy threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of $25~M_{\sun}$ at a distance less than 690~pc with 3$\sigma$ significance before the supernova. This limit is dependent on the neutrino mass ordering and background levels. KamLAND takes data continuously and can provide a supernova alert to the community.