Probing a diffuse flux of axion-like particles from galactic supernovae with neutrino water Cherenkov detectors

TL;DR

This paper investigates the potential to detect MeV-mass axion-like particles produced in galactic supernovae using water Cherenkov detectors, providing new constraints and prospects for future observations.

Contribution

It introduces a novel method to constrain ALPs via supernova-produced flux detection in water Cherenkov detectors, extending current bounds significantly.

Findings

Super-Kamiokande data set new ALP parameter constraints.

Future Hyper-Kamiokande can probe smaller couplings, improving sensitivity.

Constraints exclude a region of ALP parameter space above SN 1987A bounds.

Abstract

In this article, we claim that axion-like particles (ALPs) with MeV masses can be produced with semi-relativistic velocities in core-collapse supernovae (SNe), generating a diffuse galactic flux. We show that these ALPs can be detected in neutrino water Cherenkov detectors via $a \, p \rightarrow p \, \gamma$ interactions. Using Super-Kamiokande data, we derive new constraints on the ALP parameter space, excluding a region spanning one order of magnitude in the ALP-proton coupling above cooling bounds for ALP masses in the range of $1-70$~MeV and ALP-proton couplings between $\sim 2\times10^{-5}-2\times10^{-4}$. We show that the future Hyper-Kamiokande will be able to probe couplings as small as $\sim 10^{-5}$, considerably constraining the allowed region above SN 1987A cooling bounds.