@article{medlin_korobkina_teander_wehring_sharapov_hawari_huffman_young_palmquist_morano_et al._2024, title={External Moderation of Reactor Core Neutrons for Optimized Production of Ultra-Cold Neutrons}, url={https://doi.org/10.3390/jne5040030}, DOI={10.3390/jne5040030}, abstractNote={The ultra-cold neutron (UCN) source being commissioned at North Carolina State University’s PULSTAR reactor is uniquely optimized for UCN production in the former graphite-filled thermal column outside of the reactor pool. The source utilizes a remote moderation design, which is particularly well suited to the PULSTAR reactor because of its high thermal and epithermal neutron leakage from the core face. This large non-equilibrium flux from the core is efficiently transported to the UCN source through the specially designed beam port in order to optimize UCN production at any given reactor power. The increased distance to the source from the core also greatly limits the heat load on the cryogenic system. A MCNP (Monte Carlo N-Particle) model of this system was developed and is in good agreement with gold foil activation measurements using a test configuration as well as with the real UCN source’s heavy water moderator. These results established a firm baseline for estimates of the cold neutron flux available for UCN production and prove that remote moderation in a thermal column port is a valuable option for future designs of cryogenic UCN sources.}, journal={Journal of Nuclear Engineering}, author={Medlin, Graham and Korobkina, Ekaterina and Teander, Cole and Wehring, Bernard and Sharapov, Eduard and Hawari, Ayman I. and Huffman, Paul and Young, Albert R. and Palmquist, Grant and Morano, Matthew and et al.}, year={2024}, month={Oct} }
 @article{nesvizhevsky_henry_dauga_clavier_le floch_lychagin_muzychka_nezvanov_pischedda_teander_et al._2024, title={Poly(dicarbon monofluoride) (C<sub>2</sub>F)<sub>n</sub> bridges the neutron reflectivity gap}, volume={227}, ISSN={["1873-3891"]}, url={https://doi.org/10.1016/j.carbon.2024.119249}, DOI={10.1016/j.carbon.2024.119249}, abstractNote={Graphites covalently intercalated with fluorine to form (C2F)n structural type compounds shows a dramatic increase of the interlayer distance up to by a factor of almost 3 to reach ∼9 Å. Such graphite fluoride compounds containing only carbon and fluorine offer the rare opportunity to bridge the so-called gap in the reflectivity of neutron reflectors. Slow neutron reflectors are of great interest in designing neutron sources as well as in fundamental and applied science; they require synthesizing high thermal and chemical compound stability graphite fluorides. In this work, a new strategy is proposed for synthesizing (C2F)n compounds in a well-controlled method. Our results show that the outcome (C2F)n has a covalent character with only sp3 hybridized carbon atoms. Moreover, C-F bonds in the fluorocarbon sheets and CF2 groups on the sheet edges lead to the desired stability and hydrophobic character. A dedicated home-made neutron diffractometer was built for measurements of double-differential neutron cross sections of crystals with specific large interlayer distances found in (C2F)n compounds. We demonstrate that the synthesized fluorine intercalated graphites developed effectively cover the gap in the reflectivity for the new generation of neutron reflectors.}, journal={CARBON}, author={Nesvizhevsky, Valery and Henry, Killian and Dauga, Louise and Clavier, Batiste and Le Floch, Sylvie and Lychagin, Egor and Muzychka, Alexei and Nezvanov, Alexander and Pischedda, Vittoria and Teander, Cole and et al.}, year={2024}, month={Jun} }
 @article{korobkina_berkutov_golub_huffman_hickman_leung_medlin_morano_rao_teander_et al._2022, title={Growing solid deuterium for UCN production}, volume={24}, ISSN={["1477-2655"]}, DOI={10.3233/JNR-220010}, abstractNote={We have experimentally studied growing a large (about 1 liter) ortho-deuterium crystal in a real UCN source cryostat and recorded the growing process optically using a camera. The best quality was observed when growing the crystal directly from a vapor phase. The crystal was grown at different mass flows of deuterium and annealed at different temperatures. Optimum conditions were found for both, obtaining an optically transparent crystal and cooling it down with minimal damage. We found that the quality, final shape and changes during annealing of the crystal are very much dependent on the temperature profile of the cryostat walls.}, number={2}, journal={JOURNAL OF NEUTRON RESEARCH}, author={Korobkina, Ekaterina and Berkutov, Igor and Golub, Robert and Huffman, Paul and Hickman, Clark and Leung, Kent and Medlin, Graham and Morano, Matthew J. and Rao, Thomas and Teander, Cole and et al.}, year={2022}, pages={179–191} }