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Title: Electric charging effects on insulating surfaces in cryogenic liquids
This paper presents a new technique to study the adsorption and desorption of ions and electrons on insulating surfaces in the presence of strong electric fields in cryoliquids. The experimental design consists of a compact cryostat coupled with a sensitive electro-optical Kerr device to monitor the stability of the electric fields. The behavior of nitrogen and helium ions on a poly(methyl methacrylate) (PMMA) surface was compared to a PMMA surface coated with a mixture of deuterated polystyrene and deuterated polybutadiene. Ion accumulation and removal on these surfaces were unambiguously observed. Within the precision of the data, both surfaces behave similarly for the physisorbed ions. The setup was also used to measure the (quasi-)static dielectric constant of PMMA at T ≈ 70 K. The impact of the ion adsorption on the search for a neutron permanent electric dipole moment in a cryogenic environment, such as the nEDM@SNS experiment, is discussed.  more » « less
Award ID(s):
2232117 2110898
PAR ID:
10500320
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Review of Scientific Instruments
Volume:
95
Issue:
4
ISSN:
0034-6748
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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