Search for axioelectric effect of 5.5 MeV solar axions using BGO detectors

TL;DR

This study searches for solar axions at 5.5 MeV using BGO detectors, setting new limits on axion couplings and constraining hadronic axion masses between 0.1 and 1 MeV.

Contribution

It provides the first model-independent limits on axion-nucleon and axion-electron couplings from solar axion detection with BGO detectors.

Findings

Set a limit on the product of axion-electron and axion-nucleon couplings: |g_Ae × g_AN^3| < 2.9×10^{-9}

Constrained axion-electron coupling for hadronic axions in the 0.1-1 MeV mass range: |g_Ae| ≤ (1.4-9.7)×10^{-7}

Performed the first search for 5.5 MeV solar axions using BGO detectors in a low-background setup.

Abstract

A search for axioelectric absorption of solar axions produced in the $ p + d \rightarrow {^3\rm{He}}+\gamma (5.5 \rm{MeV})$ reactions has been performed with a BGO detector placed in a low-background setup. A model-independent limit on an axion-nucleon and axion-electron coupling constant has been obtained: $| g_{Ae}\times g_{AN}^3|< 2.9\times 10^{-9}$ for 90% confidence level. The constrains of the axion-electron coupling have been obtained for hadronic axion with masses in (0.1 - 1) MeV range: $|g_{Ae}| \leq (1.4 - 9.7)\times 10^{-7}$.