skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector

Abstract

The DEAP-3600 experiment is searching for weakly interacting massive particles dark matter with a 3.3 × 103kg single phase liquid argon (LAr) target, located 2.1 km underground at SNOLAB. The experimental signature of dark matter interactions is kilo electron volt–scale 40 Ar nuclear recoils producing 128 nm LAr scintillation photons observed by photomultiplier tubes. The largest backgrounds in DEAP-3600 are electronic recoils (ERs) induced by β and γ rays originating from internal and external radioactivity in the detector material. A background model of the ER interactions in DEAP-3600 was developed and is described in this work. The model is based on several components which are expected from radioisotopes in the LAr, from ex situ material assay measurements, and from dedicated independent in situ analyses. This prior information is used in a Bayesian fit of the ER components to a 247.2 d dataset to model the radioactivity in the surrounding detector materials. Pulse-shape discrimination separates ER and NR events. However, detailed knowledge of the ER background and activity of detector components sets valuable constraints on NR backgrounds including neutrons and alphas. In addition, the activity of 42 Ar in LAr in DEAP-3600 is determined by measuring the daughter decay of 42more » K. Finally, this cosmogenically activated trace isotope is a relevant background at higher energies for other rare event searches using atmospheric argon, e.g., DarkSide-20k, GERDA, or LEGEND. The specific activity of 42 Ar in the atmosphere is found to be 40.4 ± 5.9 μ Bq/kg of argon.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ORCiD logo; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
Contributing Org.:
DEAP Collaboration
OSTI Identifier:
1582372
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 100; Journal Issue: 7; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; Beta decay; particle dark matter; rare & new isotopes; dark matter detectors

Citation Formats

Ajaj, R., Araujo, G. R., Batygov, M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, M., Chen, Y., Cleveland, B. T., Dering, K., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, X., Litvinov, O., Lock, J., Longo, G., Majewski, P., McDonald, A. B., McElroy, T., McGinn, T., McLaughlin, J. B., Mehdiyev, R., Mielnichuk, C., Monroe, J., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Sanchez García, E., Santorelli, R., Seeburn, N., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stone, C., Strickland, V., Sur, B., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A. Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector. United States: N. p., 2019. Web. https://doi.org/10.1103/physrevd.100.072009.
Ajaj, R., Araujo, G. R., Batygov, M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, M., Chen, Y., Cleveland, B. T., Dering, K., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, X., Litvinov, O., Lock, J., Longo, G., Majewski, P., McDonald, A. B., McElroy, T., McGinn, T., McLaughlin, J. B., Mehdiyev, R., Mielnichuk, C., Monroe, J., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Sanchez García, E., Santorelli, R., Seeburn, N., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stone, C., Strickland, V., Sur, B., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., & Zuñiga-Reyes, A. Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector. United States. https://doi.org/10.1103/physrevd.100.072009
Ajaj, R., Araujo, G. R., Batygov, M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, M., Chen, Y., Cleveland, B. T., Dering, K., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, X., Litvinov, O., Lock, J., Longo, G., Majewski, P., McDonald, A. B., McElroy, T., McGinn, T., McLaughlin, J. B., Mehdiyev, R., Mielnichuk, C., Monroe, J., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Sanchez García, E., Santorelli, R., Seeburn, N., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stone, C., Strickland, V., Sur, B., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A. Wed . "Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector". United States. https://doi.org/10.1103/physrevd.100.072009. https://www.osti.gov/servlets/purl/1582372.
@article{osti_1582372,
title = {Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector},
author = {Ajaj, R. and Araujo, G. R. and Batygov, M. and Beltran, B. and Bina, C. E. and Boulay, M. G. and Broerman, B. and Bueno, J. F. and Burghardt, P. M. and Butcher, A. and Cai, B. and Cárdenas-Montes, M. and Cavuoti, S. and Chen, M. and Chen, Y. and Cleveland, B. T. and Dering, K. and Duncan, F. A. and Dunford, M. and Erlandson, A. and Fatemighomi, N. and Fiorillo, G. and Flower, A. and Ford, R. J. and Gagnon, R. and Gallacher, D. and García Abia, P. and Garg, S. and Giampa, P. and Goeldi, D. and Golovko, V. V. and Gorel, P. and Graham, K. and Grant, D. R. and Hallin, A. L. and Hamstra, M. and Harvey, P. J. and Hearns, C. and Joy, A. and Jillings, C. J. and Kamaev, O. and Kaur, G. and Kemp, A. and Kochanek, I. and Kuźniak, M. and Langrock, S. and La Zia, F. and Lehnert, B. and Li, X. and Litvinov, O. and Lock, J. and Longo, G. and Majewski, P. and McDonald, A. B. and McElroy, T. and McGinn, T. and McLaughlin, J. B. and Mehdiyev, R. and Mielnichuk, C. and Monroe, J. and Nadeau, P. and Nantais, C. and Ng, C. and Noble, A. J. and Ouellet, C. and Pasuthip, P. and Peeters, S. J. M. and Pesudo, V. and Piro, M. -C. and Pollmann, T. R. and Rand, E. T. and Rethmeier, C. and Retière, F. and Sanchez García, E. and Santorelli, R. and Seeburn, N. and Skensved, P. and Smith, B. and Smith, N. J. T. and Sonley, T. and Stainforth, R. and Stone, C. and Strickland, V. and Sur, B. and Vázquez-Jáuregui, E. and Veloce, L. and Viel, S. and Walding, J. and Waqar, M. and Ward, M. and Westerdale, S. and Willis, J. and Zuñiga-Reyes, A.},
abstractNote = {The DEAP-3600 experiment is searching for weakly interacting massive particles dark matter with a 3.3 × 103kg single phase liquid argon (LAr) target, located 2.1 km underground at SNOLAB. The experimental signature of dark matter interactions is kilo electron volt–scale 40 Ar nuclear recoils producing 128 nm LAr scintillation photons observed by photomultiplier tubes. The largest backgrounds in DEAP-3600 are electronic recoils (ERs) induced by β and γ rays originating from internal and external radioactivity in the detector material. A background model of the ER interactions in DEAP-3600 was developed and is described in this work. The model is based on several components which are expected from radioisotopes in the LAr, from ex situ material assay measurements, and from dedicated independent in situ analyses. This prior information is used in a Bayesian fit of the ER components to a 247.2 d dataset to model the radioactivity in the surrounding detector materials. Pulse-shape discrimination separates ER and NR events. However, detailed knowledge of the ER background and activity of detector components sets valuable constraints on NR backgrounds including neutrons and alphas. In addition, the activity of 42 Ar in LAr in DEAP-3600 is determined by measuring the daughter decay of 42 K. Finally, this cosmogenically activated trace isotope is a relevant background at higher energies for other rare event searches using atmospheric argon, e.g., DarkSide-20k, GERDA, or LEGEND. The specific activity of 42 Ar in the atmosphere is found to be 40.4 ± 5.9 μ Bq/kg of argon.},
doi = {10.1103/physrevd.100.072009},
journal = {Physical Review D},
number = 7,
volume = 100,
place = {United States},
year = {2019},
month = {10}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

First Results from the DEAP-3600 Dark Matter Search with Argon at SNOLAB
journal, August 2018


Expected atmospheric concentration of 42Ar
journal, September 1997

  • Peurrung, A. J.; Bowyer, T. W.; Craig, R. A.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 396, Issue 3
  • DOI: 10.1016/S0168-9002(97)00819-X

Backgrounds and pulse shape discrimination in the ArDM liquid argon TPC
journal, December 2018


BAT – The Bayesian analysis toolkit
journal, November 2009

  • Caldwell, Allen; Kollár, Daniel; Kröninger, Kevin
  • Computer Physics Communications, Vol. 180, Issue 11
  • DOI: 10.1016/j.cpc.2009.06.026

In-situ characterization of the Hamamatsu R5912-HQE photomultiplier tubes used in the DEAP-3600 experiment
journal, April 2019

  • Amaudruz, P. -A.; Batygov, M.; Beltran, B.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 922
  • DOI: 10.1016/j.nima.2018.12.058

On atmospheric 39Ar and 42Ar abundance
journal, March 1995

  • Cennini, P.; Cittolin, S.; Dzialo Giudice, D.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 356, Issue 2-3
  • DOI: 10.1016/0168-9002(94)01234-2

The SNOLAB deep underground facility
journal, September 2012


Planck 2015 results : XXIII. The thermal Sunyaev-Zeldovich effect-cosmic infrared background correlation
journal, September 2016


Ultra-low background measurement capabilities at SNOLAB
journal, May 2016


Planck 2015 results : XIII. Cosmological parameters
journal, September 2016


The background in the $$0\nu \beta \beta $$ 0 ν β β experiment Gerda
journal, April 2014


Geant4—a simulation toolkit
journal, July 2003

  • Agostinelli, S.; Allison, J.; Amako, K.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 506, Issue 3
  • DOI: 10.1016/S0168-9002(03)01368-8

Search for dark matter with a 231-day exposure of liquid argon using DEAP-3600 at SNOLAB
journal, July 2019


The André E. Lalonde AMS Laboratory – The new accelerator mass spectrometry facility at the University of Ottawa
journal, October 2015

  • Kieser, W. E.; Zhao, X. -L.; Clark, I. D.
  • Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol. 361
  • DOI: 10.1016/j.nimb.2015.03.014

Event generator DECAY4 for simulating double-beta processes and decays of radioactive nuclei
journal, July 2000

  • Ponkratenko, O. A.; Tretyak, V. I.; Zdesenko, Yu. G.
  • Physics of Atomic Nuclei, Vol. 63, Issue 7
  • DOI: 10.1134/1.855784

Design and construction of the DEAP-3600 dark matter detector
journal, March 2019


Measurement of the specific activity of 39Ar in natural argon
journal, April 2007

  • Benetti, P.; Calaprice, F.; Calligarich, E.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 574, Issue 1
  • DOI: 10.1016/j.nima.2007.01.106

On concentration of 42Ar in the Earth's atmosphere
journal, December 2016

  • Barabash, A. S.; Saakyan, R. R.; Umatov, V. I.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 839
  • DOI: 10.1016/j.nima.2016.09.042

New experimental limit on the 42Ar content in the Earth’s atmosphere
journal, October 1998

  • Ashitkov, V. D.; Barabash, A. S.; Belogurov, S. G.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 416, Issue 1
  • DOI: 10.1016/S0168-9002(98)00740-2

Luminosity determination in pp collisions at $$\sqrt{s}$$ s = 8 TeV using the ATLAS detector at the LHC
journal, November 2016


DarkSide-50 532-day dark matter search with low-radioactivity argon
journal, November 2018