Measurements and models of enhanced recombination following inner-shell vacancies in liquid xenon
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Electron-capture decays of
125
Xe
and
127
Xe
, and double-electron-capture decays of
124
Xe
, are backgrounds in searches for weakly interacting massive particles (WIMPs) conducted by dual-phase xenon time projection chambers such as LUX-ZEPLIN (LZ). These decays produce signals with more light and less charge than equivalent-energy 𝛽 decays and correspondingly overlap more with WIMP signals. We measure three electron-capture charge yields in LZ: the 1.1 keV M-shell, 5.2 keV L-shell, and 33.2 keV K-shell at drift fields of 193 and 96.5 V/cm. The LL double-electron-capture decay of
124
Xe
exhibits even more pronounced shifts in charge and light. We provide a first model of double-electron-capture charge yields using the link between ionization density and electron-ion recombination, and identify a need for more accurate calculations. Finally, we discuss the implications of the reduced charge yield of these decays and other interactions creating inner-shell vacancies for future dark matter searches.
125
Xe
and
127
Xe
, and double-electron-capture decays of
124
Xe
, are backgrounds in searches for weakly interacting massive particles (WIMPs) conducted by dual-phase xenon time projection chambers such as LUX-ZEPLIN (LZ). These decays produce signals with more light and less charge than equivalent-energy 𝛽 decays and correspondingly overlap more with WIMP signals. We measure three electron-capture charge yields in LZ: the 1.1 keV M-shell, 5.2 keV L-shell, and 33.2 keV K-shell at drift fields of 193 and 96.5 V/cm. The LL double-electron-capture decay of
124
Xe
exhibits even more pronounced shifts in charge and light. We provide a first model of double-electron-capture charge yields using the link between ionization density and electron-ion recombination, and identify a need for more accurate calculations. Finally, we discuss the implications of the reduced charge yield of these decays and other interactions creating inner-shell vacancies for future dark matter searches.
Date Issued
2025-07-30
Date Acceptance
2025-05-19
Citation
Physical Review D: Particles, Fields, Gravitation and Cosmology, 2025, 112 (1)
ISSN
1550-7998
Publisher
American Physical Society
Journal / Book Title
Physical Review D: Particles, Fields, Gravitation and Cosmology
Volume
112
Issue
1
Copyright Statement
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3 .
License URL
Subjects
ARGON
Astronomy & Astrophysics
GRIDPP
Physical Sciences
Physics
Physics, Particles & Fields
Science & Technology
Publication Status
Published
Article Number
012024
Date Publish Online
2025-07-30