Search for solar axions produced by Compton process and bremsstrahlung using axioelectric effect

TL;DR

This study searches for solar axions produced by bremsstrahlung and Compton processes using the axioelectric effect in silicon, setting new constraints on axion-electron coupling and axion mass in specific models.

Contribution

It provides a model-independent experimental constraint on axion-electron coupling and bounds on axion mass in DFSZ and KSVZ models using a silicon detector in a low-background environment.

Findings

Constraint on axion-electron coupling: |g_Ae| ≤ 2.2×10^−10

Axion mass bounds: m_A ≤ 7.9 eV (DFSZ), m_A ≤ 1.4 keV (KSVZ)

No detection of solar axions in the experiment

Abstract

The axio-electric effect in silicon atoms is sought for solar axions appearing owing to bremsstrahlung and the Compton process. Axions are detected using a Si(Li) detector placed in a low-background setup. As a result, a model-independent constraint on the axion-electron coupling constant $|g_{Ae}| \leq 2.2\times 10^{-10}$ has been obtained, which leads to the bounds $m_{A}\leq$ 7.9 eV and $m_{A}\leq$ 1.4 keV for the mass of the axion in the DFSZ and KSVZ models, respectively (90% C.L.).