Pushing the limits of pulse shape discrimination in a large liquid xenon detector

Abstract The LUX-ZEPLIN (LZ) experiment is a direct-detection dark matter experiment, optimized to search for weakly interacting massive particles (WIMPs) through WIMP-nucleon interactions. The main challenge in dark matter detection is differentiating between WIMP signals and background events. In LZ, the ratio of ionization to scintillation signals (charge-to-light) is the primary method for rejecting electronic recoil (ER) background. Pulse shape discrimination (PSD) offers a method for additional ER backgrounds rejection in liquid xenon detectors. In this paper, the discrimination power of PSD with the LZ experiment is discussed. To precisely characterize the scintillation pulse shape, an analysis framework is developed to reconstruct the detection time of individual photons. Using LZ calibration data, the photon-timing tail fraction discriminator is optimized and achieves ER leakage as low as $$15\\%$$ 15 % . For specific background processes such as $$^{124}$$ 124 Xe double electron capture, the leakage is reduced further to about $$5\\%$$ 5 % . PSD is combined with charge-to-light to form two-factor discrimination (TFD). The optimized TFD performance is compared with the performance of the charge-to-light method, with the corresponding false positive rate reduced by up to a factor of two for large scintillation pulses. Finally, PSD and TFD are applied to data from LZ’s WS2024 run and their performance is summarized.

Authors

Institutions

Publication Details

Journal
The European Physical Journal C
Published
2026-09-11
DOI
https://doi.org/10.1140/epjc/s10052-026-16216-8
Primary Topic
Dark Matter and Cosmic Phenomena
Type
article
Field-Weighted Citation Impact
0.00
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
article

Pushing the limits of pulse shape discrimination in a large liquid xenon detector

F. Alder, J. E. Armstrong, G. J. Homenides, E. Jacquet et al.
The European Physical Journal C
Dark Matter and Cosmic Phenomena
article

Pushing the limits of pulse shape discrimination in a large liquid xenon detector

F. Alder, J. E. Armstrong, G. J. Homenides, E. Jacquet, S. A. Hertel, R. H. Hampp, S. R. Eriksen, L. Kreczko, R. S. James, D. Khaitan, T. P. Biesiadzinski, S. Dey, J. E. Y. Dobson, M. G. D. van der Grinten, C. Ghag, H. Flaecher, T. M. A. Fruth, P. W. Gaemers, M. C. Carmona-Benitez, T. Hall, C. Lawes, N. Fieldhouse, S. Fiorucci, J. Green, B. J. Almquist, J S Kim, Y. D. Kim, S. Burdin, M. Horn, C. A. J. Brew, A. Ames, A. C. Kamaha, M. A. Hernandez, D. Kodroff, L. Di Felice, V. A. Kudryavtsev, E. V. Korolkova, K. Beattie, C. Ding, C. E. Dahl, K. Jenkins, M. V. Converse, D. S. Leonard, E. Bishop, N. M. Fearon, Y. T. Chin, J. Delgaudio, M. Arthurs, J. Genovesi, D. Q. Huang, E. Druszkiewicz, S. Gokhale, M. K. Kannichankandy, A. Bhatti, A. David, A. Cottle, A. Baker, E. E. Barillier, E. D. Fraser, A. Khazov, H. J. Birch, C. L. Dunbar, K. T. Lesko, D. S. Akerib, R. J. Gaitskell, A. Ghosh, I. Darlington, G. M. Blockinger, S. Dubey, A. K. Al Musalhi, J. W. Bargemann, S. Contreras, S. Dave, S. Kravitz, S. Balashov, N. Angelides, H. M. Araújo, M. Carter, S. Ghosh, D. Curran, L. de Viveiros, H. Y. Chen, A. Geffre, S. J. Haselschwardt, J. Ghamsari, C. S. Amarasinghe, G. Cox, D. Hunt, J. J. Haiston, A. Chawla, E. B. Leon, J. Bang, N. I. Chott, H. Kraus, T. J. Anderson, R. Gibbons, P. Brás, A. C. Kaboth, R. Coronel, C. R. Hall
article en

Abstract

Abstract The LUX-ZEPLIN (LZ) experiment is a direct-detection dark matter experiment, optimized to search for weakly interacting massive particles (WIMPs) through WIMP-nucleon interactions. The main challenge in dark matter detection is differentiating between WIMP signals and background events. In LZ, the ratio of ionization to scintillation signals (charge-to-light) is the primary method for rejecting electronic recoil (ER) background. Pulse shape discrimination (PSD) offers a method for additional ER backgrounds rejection in liquid xenon detectors. In this paper, the discrimination power of PSD with the LZ experiment is discussed. To precisely characterize the scintillation pulse shape, an analysis framework is developed to reconstruct the detection time of individual photons. Using LZ calibration data, the photon-timing tail fraction discriminator is optimized and achieves ER leakage as low as $$15\%$$ 15 % . For specific background processes such as $$^{124}$$ 124 Xe double electron capture, the leakage is reduced further to about $$5\%$$ 5 % . PSD is combined with charge-to-light to form two-factor discrimination (TFD). The optimized TFD performance is compared with the performance of the charge-to-light method, with the corresponding false positive rate reduced by up to a factor of two for large scintillation pulses. Finally, PSD and TFD are applied to data from LZ’s WS2024 run and their performance is summarized.

The European Physical Journal CVol. 86(9)
Rutherford Appleton Laboratory (GB), The University of Sydney (AU), Pennsylvania State University (US), Fermi National Accelerator Laboratory (US), University of Liverpool (GB), Lawrence Berkeley National Laboratory (US), University of California, Los Angeles (US), The University of Melbourne (AU), University of Alabama (US), King's College London (GB), Royal Holloway University of London (GB), South Dakota School of Mines and Technology (US), Brookhaven National Laboratory (US), University of Zurich (CH), Brown University (US), University of Michigan (US), SLAC National Accelerator Laboratory (US), University of California System (US), University of Bristol (GB), University at Albany, State University of New York (US), University of Oxford (GB), South Dakota Science and Technology Authority (US), University College London (GB), Imperial College London (GB), University of Rochester (US), University of Maryland, College Park (US), University of Coimbra (PT), The University of Texas at Austin (US), University of Sheffield (GB), Stanford University (US), University of Edinburgh (GB)
Reduced inequalities
Openalex Percentile: Top 73%
Dark Matter and Cosmic Phenomena
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.