The upcoming UCNProBe experiment at Los Alamos National Laboratory will measure the β-decay rate of free neutrons with different systematic uncertainties than previous beam-based neutron lifetime experiments. We have developed a new 10B-coated YAP:Ce scintillator whose properties are presented. The advantage of the YAP:Ce scintillator is its high Fermi potential, which reduces the probability for upscattering of ultracold neutrons, and its short decay time, which is important at high counting rates. Birks' coefficient of YAP:Ce was measured to be (5.56−0.30+0.05)×10−4 cm/MeV and light losses due to 120 nm of 10B-coating to be about 60%. The loss of light from YAP:Ce due to transmission through deuterated polystyrene scintillator was about 50%. The efficiency for counting neutrons that are captured on the 10B coating is (86.82 ± 2.61)%. Measurement with ultracold neutrons showed that YAP:Ce crystal counted 8% to 28% more UCNs compared to ZnS screen. This may be due to an uneven coating of 10B on the rough surface.
@article{arxiv.2405.02309,
title = {YAP:Ce scintillator as an absolute ultracold neutron detector},
author = {M. Krivoš and Z. Tang and N. Floyd and C. L. Morris and M. Blatnik and C. Cude-Woods and S. M. Clayton and A. T. Holley and T. M. Ito and C. -Y. Liu and M. Makela and I. F. Martinez and A. S. C. Navazo and C. M. O'Shaughnessy and E. L. Renner and R. W. Pattie and A. R. Young},
journal= {arXiv preprint arXiv:2405.02309},
year = {2024}
}