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Title: Scintillation characteristics of the EJ-299-02H scintillator
A study of the dead layer thickness and quenching factor of a plastic scintillator for use in ultracold neutron (UCN) experiments is described. Alpha spectroscopy was used to determine the thickness of a thin surface dead layer to be 630 ± 110 nm. The relative light outputs from the decay of 241Am and Compton scattering of electrons were used to extract Birks’ law coefficient, yielding a kB value of 0.087 ± 0.003 mm/MeV, consistent with some previous reports for other polystyrene-based scintillators. The results from these measurements are incorporated into the simulation to show that an energy threshold of (∼9 keV) can be achieved for the UCNProBe experiment. This low threshold enables high beta particle detection efficiency and the indirect measurement of UCN. The ability to make the scintillator deuterated, accompanied by its relatively thin dead layer, gives rise to unique applications in a wide range of UCN experiments, where it can be used to trap UCN and detect charged particles in situ.  more » « less
Award ID(s):
2209590
PAR ID:
10528900
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
NA
Publisher / Repository:
APS
Date Published:
Journal Name:
Review of Scientific Instruments
Edition / Version:
1
Volume:
95
Issue:
4
ISSN:
0034-6748
Page Range / eLocation ID:
023305
Subject(s) / Keyword(s):
fundamental neutron physics, fundamental symmetries, beta detectors, scintillator detectors, ultracold neutrons, particle physics, neutron beta decay
Format(s):
Medium: X Size: 1.02 MB Other: pdf
Size(s):
1.02 MB
Sponsoring Org:
National Science Foundation
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