# A Test of Bolometric Properties of Tm-containing Crystals as a Perspective Detector for the Solar Axion Search

## TL;DR

This paper investigates the potential of Tm-containing garnet crystals as bolometric detectors for solar axion searches, focusing on their nuclear and optical properties, and discusses the requirements for future low-background experiments.

## Contribution

It presents the growth and testing of Tm$_3$Al$_5$O$_{12}$ crystals for use in solar axion detection, highlighting their bolometric and optical characteristics and contamination levels.

## Key findings

- Successful growth and testing of Tm$_3$Al$_5$O$_{12}$ crystal
- Assessment of chemical and radioactive contamination levels
- Estimation of requirements for low-background experimental setup

## Abstract

The $^{169}$Tm nuclide has first nuclear level at 8.41 keV with magnetic type transition to the ground state and, therefore, can be used as a target nucleus for the search of resonant absorption of solar axions. We plan to use a Tm-containing crystal of a garnet family Tm$_3$Al$_5$O$_{12}$ as a bolometric detector in order to search for the excitation of the first nuclear level of $^{169}$Tm via the resonant absorption of solar axions. With this perspective in mind, a sample of the Tm$_3$Al$_5$O$_{12}$ crystal was grown and tested for its bolometric and optical properties. Measurements of chemical and/or radioactive contaminations were performed as well. In this paper we present the test results and estimate the requirements for a future low-background experimental setup.