Detection of ultracold neutrons with powdered scintillator screens
M. Krivos, N. C. Floyd, C. L. Morris, Z. Tang, M. Blatnik, S. M. Clayton, C. B. Cude-Woods, A. Fratangelo, A. T. Holley, D. E. Hooks, T. M. Ito, C. -Y. Liu, M. Makela, M. R. Martinez, A. S. C. Navazo, C., M. O'Shaughnessy, R. W. Pattie, E. L. Renner, T. A. Sandborn, T. J. Schaub, M. Singh, I. L. Smythe, F. W. Uhrich, N. K. Washecheck, Z. Wang, A. R. Young
Published: 2025/9/4
Abstract
Zinc sulfide (ZnS:Ag) scintillators are widely used for ultracold neutron (UCN) detection, but their application is limited by long decay times and pronounced phosphorescence. We tested two possible replacement scintillators: yttrium aluminum perovskite (YAP:Ce) and lutetium yttrium orthosilicate (LYSO:Ce). Both have decay times on the order of 30-40 ns, which can help reduce dead time in high count rate experiments. YAP:Ce showed a 60% lower phosphorescence when compared to ZnS:Ag after 2 days and outperformed ZnS:Ag in counting UCN by about 20%. On the other hand, LYSO:Ce exhibited more phosphorescence and produced fewer UCN counts compared to both ZnS:Ag and YAP:Ce. Both of these scintillators are viable UCN detectors for high count rate experiments, but YAP:Ce outperformed LYSO:Ce by every tested metric.