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arXiv · 2607.03033

A New High-Intensity Source for Ultracold Neutrons

K. Abe·S. Ahmed·B. Algohi·D. Anthony·L. Barron-Palos·Y. Bylinsky·M. Bosse·M. P. Bradley·A. Brossard·J. Chak·R. Chiba·C. Davis·R. de Vries·K. Dong·K. Drury·B. Franke·D. Fujimoto·R. Fujitani·M. Gericke·P. Giampa·C. Gibson·R. Golub·K. Hatanaka·T. Hepworth·T. Higuchi·A. Jaison·B. Jamieson·K. Jorgensen-Fullam·M. Katotoka·S. Kawasaki·M. Kitaguchi·W. Klassen·E. Klemets·E. Korkmaz·E. Korobkina·F. Kuchler·C. Lamb·M. Lavvaf·A. Lejuez·T. Lightbody·T. Lindner·S. Longo·K. W. Madison·J. Malcolm·J. Mammei·R. Mammei·C. Marshall·J. W. Martin·R. Matsumiya·M. McCrea·E. Miller·M. Miller·K. Mishima·T. Mohammadi·T. Momose·M. Nalbandian·T. Okamura·S. Pankratz·R. Patni·R. Picker·V. Purcell·K. Qiao·Y. -N. Rao·W. Rathnakela·T. Reimer·D. Salazar·W. Schreyer·T. Shima·H. M. Shimizu·S. Sidhu·S. Stargardter·R. Stutters·P. Switzer·Tushar·M. Uzair·S. Vanbergen·W. T. H. van Oers·N. Yazdandoost·Q. Ye·A. Zahra·L. Zhang
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Abstract

The TRIUMF UltraCold Advanced Neutron (TUCAN) collaboration has completed a new superthermal source for ultracold neutrons (UCNs) at TRIUMF. It uses neutrons from a spallation target driven by TRIUMF's %520-MeV main cyclotron. Heavy water and liquid deuterium serve as neutron moderators, and inelastic scattering inside superfluid $^4$He at around \qty{1.1}{\kelvin} slows the neutrons down to become ultracold. During commissioning runs with the completed source, including the deuterium moderator, up to $1.47(2)\times 10^7$ UCNs were detected in the experimental area after irradiating the target and accumulating UCNs in the source for \qty{60}{\second}. Up to \qty{6.75(3)e5} UCN/s were detected during continuous operation, more than at any other source in the world.

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K. Abe, S. Ahmed, B. Algohi, D. Anthony, L. Barron-Palos, Y. Bylinsky, M. Bosse, M. P. Bradley, A. Brossard, J. Chak, R. Chiba, C. Davis, R. de Vries, K. Dong, K. Drury, B. Franke, D. Fujimoto, R. Fujitani, M. Gericke, P. Giampa, C. Gibson, R. Golub, K. Hatanaka, T. Hepworth, T. Higuchi, A. Jaison, B. Jamieson, K. Jorgensen-Fullam, M. Katotoka, S. Kawasaki, M. Kitaguchi, W. Klassen, E. Klemets, E. Korkmaz, E. Korobkina, F. Kuchler, C. Lamb, M. Lavvaf, A. Lejuez, T. Lightbody, T. Lindner, S. Longo, K. W. Madison, J. Malcolm, J. Mammei, R. Mammei, C. Marshall, J. W. Martin, R. Matsumiya, M. McCrea, E. Miller, M. Miller, K. Mishima, T. Mohammadi, T. Momose, M. Nalbandian, T. Okamura, S. Pankratz, R. Patni, R. Picker, V. Purcell, K. Qiao, Y. -N. Rao, W. Rathnakela, T. Reimer, D. Salazar, W. Schreyer, T. Shima, H. M. Shimizu, S. Sidhu, S. Stargardter, R. Stutters, P. Switzer, Tushar, M. Uzair, S. Vanbergen, W. T. H. van Oers, N. Yazdandoost, Q. Ye, A. Zahra, L. Zhang. 2026-07-03. A New High-Intensity Source for Ultracold Neutrons. https://arxiv.org/abs/2607.03033

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