Detecting the Supernova Breakout Burst in Terrestrial Neutrino Detectors

TL;DR

This study evaluates the ability of terrestrial neutrino detectors to observe the supernova $ u_e$ breakout burst, considering neutrino oscillations and detector capabilities, to enhance understanding of supernova physics and neutrino properties.

Contribution

It provides the first detailed analysis of detector performance for observing the supernova breakout burst across different neutrino mass hierarchies and distances.

Findings

Inverted hierarchy allows detection of the $ u_e$ breakout burst at certain distances.

Maximum luminosity can be measured with 30-60% accuracy at 10 kpc.

Timing of the burst can be measured to within a few milliseconds at various distances.

Abstract

We calculate the distance-dependent performance of a few representative terrestrial neutrino detectors in detecting and measuring the properties of the $\nu_e$ breakout burst light curve in a Galactic core-collapse supernova. The breakout burst is a signature phenomenon of core collapse and offers a probe into the stellar core through collapse and bounce. We examine cases of no neutrino oscillations and oscillations due to normal and inverted neutrino-mass hierarchies. For the normal hierarchy, other neutrino flavors emitted by the supernova overwhelm the $\nu_e$ signal, making a detection of the breakout burst difficult. For the inverted hierarchy (IH), some detectors at some distances should be able to see the $\nu_e$ breakout burst peak and measure its properties. For the IH, the maximum luminosity of the breakout burst can be measured at 10 kpc to accuracies of $\sim$30% for Hyper-Kamiokande (Hyper-K) and $\sim$60% for the Deep Underground Neutrino Experiment (DUNE). Super-Kamiokande (Super-K) and Jiangmen Underground Neutrino Observatory (JUNO) lack the mass needed to make an accurate measurement. For the IH, the time of the maximum luminosity of the breakout burst can be measured in Hyper-K to an accuracy of $\sim$3 ms at 7 kpc, in DUNE $\sim$2 ms at 4 kpc, and JUNO and Super-K can measure the time of maximum luminosity to an accuracy of $\sim$2 ms at 1 kpc. Detector backgrounds in IceCube render a measurement of the $\nu_e$ breakout burst unlikely. For the inverted hierarchy, a measurement of the maximum luminosity of the breakout burst could be used to differentiate between nuclear equations of state.