In this paper, we describe 220Rn calibration source that was developed for liquid noble gas detectors. The key advantage of this source is that it can provide 212Bi-212Po consecutive events, which enables us to evaluate the vertex resolution of a detector at low energy by comparing low-energy events of 212Bi and corresponding higher-energy alpha-rays from 212Po. Since 220Rn is a noble gas, a hot metal getter can be used when introduced using xenon as the carrier gas. In addition, no long-life radioactive isotopes are left behind in the detector after the calibration is complete; this has clear advantage over the use of 222Rn which leaves long- life radioactivity, i.e., 210Pb. Using a small liquid xenon test chamber, we developed a system to introduce 220Rn via the xenon carrier gas; we demonstrated the successful introduction of 6 times 10^2 220Rn atoms in our test environment.
@article{arxiv.1603.02904,
title = {Using 220Rn to calibrate liquid noble gas detectors},
author = {M. Kobayashi and M. Yamashita and A. Takeda and K. Kishimoto and S. Moriyama},
journal= {arXiv preprint arXiv:1603.02904},
year = {2016}
}
Comments
6 pages,10 figures, to appear in Proceedings of the 14th international conference on Topics in Astroparticle and Underground Physics: TAUP2015, Torino, Italy