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Title: Ultracold neutron storage in a bottle coated with the fluoropolymer CYTOP
Abstract

The fluoropolymer CYTOP was investigated in order to evaluate its suitability as a coating material for ultracold neutron (UCN) storage vessels. Using neutron reflectometry on CYTOP-coated silicon wafers, its neutron optical potential was measured to be 115.2(2) neV. UCN storage measurements were carried out in a 3.8 l CYTOP-coated aluminum bottle, in which the storage time constant was found to increase from 311(9) s at room temperature to 564(7) s slightly above 10 K. By combining experimental storage data with simulations of the UCN source, the neutron loss factor of CYTOP is estimated to decrease from 1.1(1)$$\times 10^{-4}$$×10-4to 2.7(2)$$\times 10^{-5}$$×10-5at these temperatures, respectively. These results are of particular importance to the next-generation superthermal UCN source SuperSUN, currently under construction at the Institut Laue-Langevin, for which CYTOP is a possible top-surface coating in the UCN production volume.

 
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Award ID(s):
2111046
NSF-PAR ID:
10369957
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Springer Science + Business Media
Date Published:
Journal Name:
The European Physical Journal A
Volume:
58
Issue:
7
ISSN:
1434-601X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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