Kerr black holes radiate neutrinos in an asymmetric pattern, preferentially in the lower hemisphere relative to the black hole’s rotation axis, while antineutrinos are predominantly produced in the upper hemisphere. Leveraging this asymmetric emission, we explore the potential of high energy, $E_{\nu }\gtrsim 1\mathrm{TeV}$, neutrino, and antineutrino detection to reveal crucial characteristics of an evaporating primordial black hole at the time of its burst when observed near Earth. We improve upon previous calculations by carefully accounting for the nonisotropic particle emission, as Earth occupies a privileged angle relative to the black hole’s rotation axis. Additionally, we investigate the angular dependence of primary and secondary photon spectra and assess the evaporating black hole’s time evolution during the final explosive stages of its lifetime. Since photon events outnumber neutrinos by about three orders of magnitude, we find that a neutrino measurement can aid in identifying the initial angular momentum and the black hole hemisphere facing Earth only for evaporating black holes within our solar system, at distances $\lesssim {10}^{-4}\mathrm{pc}$, and observed during the final 100 s of their lifetime.

• Received 11 August 2023
• Accepted 20 September 2023

DOI:https://doi.org/10.1103/PhysRevD.108.083014

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Published by the American Physical Society