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

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.

9 pages, 6 figures, 3 tables