A long wavelength neutron monochromator for superthermal production of ultracold neutrons

✍ Scribed by C.E.H Mattoni; C.P Adams; K.J Alvine; J.M Doyle; S.N Dzhosyuk; R Golub; E Korobkina; D.N McKinsey; A.K Thompson; L Yang; H Zabel; P.R Huffman

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 430 KB
• Volume: 344
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2003.10.023

✦ Synopsis

Production of ultracold neutrons (UCN) by single-phonon downscattering of cold neutrons from superfluid helium (the ''superthermal process'') utilizes input neutrons only in a narrow wavelength band around 0:89 nm: Delivering a monochromatic 0:89 nm neutron beam to a superfluid helium target reduces backgrounds in the UCN production region with minimal loss in the UCN production rate. The design, construction, and testing of a 0:89 nm neutron monochromator is reported herein. This monochromator is constructed from nine tiled pieces of stage 2 potassiumintercalated graphite with mosaics between 1:1 and 2:1 and reflectivities of (73-91)% at 0:89 nm: In addition to stage 2 potassium-intercalated graphite, fluorophlogopite and stage 1 potassium-intercalated graphite are also characterized.