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Title: Development of a 127 Xe calibration source for nEXO
Abstract We study a possible calibration technique for the nEXO experiment using a 127 Xe electron capture source. nEXO is a next-generation search for neutrinoless double beta decay (0 νββ ) that will use a 5-tonne, monolithic liquid xenon time projection chamber (TPC). The xenon, used both as source and detection medium, will be enriched to 90% in 136 Xe. To optimize the event reconstruction and energy resolution, calibrations are needed to map the position- and time-dependent detector response. The 36.3 day half-life of 127 Xe and its small Q-value compared to that of 136 Xe 0 νββ would allow a small activity to be maintained continuously in the detector during normal operations without introducing additional backgrounds, thereby enabling in-situ calibration and monitoring of the detector response. In this work we describe a process for producing the source and preliminary experimental tests. We then use simulations to project the precision with which such a source could calibrate spatial corrections to the light and charge response of the nEXO TPC.  more » « less
Award ID(s):
2034659 1812245 2111213 2011948
NSF-PAR ID:
10358696
Author(s) / Creator(s):
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Date Published:
Journal Name:
Journal of Instrumentation
Volume:
17
Issue:
07
ISSN:
1748-0221
Page Range / eLocation ID:
P07028
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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