High-energy neutrino emission in gravitational collapses

TL;DR

This paper models high-energy neutrino emissions during gravitational collapse of compact stars, estimating fluxes, ratios, and detectable events based on particle interactions and energy conversion assumptions.

Contribution

It introduces a detailed calculation of neutrino production during stellar collapse using equilibrium equations and energy conversion assumptions, providing estimations of fluxes and detection prospects.

Findings

Estimated neutrino fluxes of 10MeV and GeV energies.

Predicted neutrino event counts in detectors like Kamiokande.

Calculated neutrino energy output exceeding 10^{53} erg.

Abstract

In this article, we present a study of high-energy neutrino emission in gravitational collapse. A compact star is treated as a complete degenerate Fermi gas of neutrons, protons and electrons. In gravitational collapse, its density reaches the thresholds for muon and pion productions, leading to high-energy neutrinos production. By using adiabatic approximation that macroscopic collapsing processes are much slower than microscopic processes of particle interactions, we adopt equilibrium equations of microscopic processes to obtain the number of neutrino productions. Assuming 10% of variation in gravitational binding energy converted to the energy of produced neutrinos, we obtain fluxes of 10MeV electron-neutrinos and GeV electron and muon neutrinos. In addition, we compute the ratio (< 1) of total muon neutrino number to the total electron neutrino number at the source and at the Earth considering neutrino oscillations. We approximately obtain the number of GeV antineutrino events (\gtrsim 1) in an ordinary detector such as Kamiokande and total energy of neutrino flux (\gtrsim 10^{53} erg), as a function of collapsing star mass.