Performance of TES X-Ray Microcalorimeters Designed for 14.4-keV Solar Axion Search
Abstract
A 57Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition if a hypothetical elementary particle, axion, exists to solve the strong CP problem. Transition edge sensor (TES) X-ray microcalorimeters can detect such axions very efficiently if they are again converted into photons by a 57Fe absorber. We have designed and produced a dedicated TES array with 57Fe absorbers for the solar axion search. The iron absorber is set next to the TES, keeping a certain distance to reduce the iron-magnetization effect on the spectroscopic performance. A gold thermal transfer strap connects them. A sample pixel irradiated from a 55Fe source detected 698 pulses. In contrast to thermal simulations, we consider that the pulses include either events produced in an iron absorber or gold strap at a fraction dependent on the absorption rate of each material. Furthermore, photons deposited on the iron absorber are detected through the strap as intended. The identification of all events still needs to be completed. However, we successfully operated the TES with the unique design under iron magnetization for the first time.
Cite
@article{arxiv.2304.07068,
title = {Performance of TES X-Ray Microcalorimeters Designed for 14.4-keV Solar Axion Search},
author = {Yuta Yagi and Ryohei Konno and Tasuku Hayashi and Keita Tanaka and Noriko Y. Yamasaki and Kazuhisa Mitsuda and Rumi Sato and Mikiko Saito and Takayuki Homma and Yoshiki Nishida and Shohei Mori and Naoko Iyomoto and Toru Hara},
journal= {arXiv preprint arXiv:2304.07068},
year = {2023}
}
Comments
10 pages, 6 figures, published in Journal of Low Temperature Physics on 4 February 2023