Search

Your search keyword '"Hamstra, M."' showing total 7 results
Start Over Author "Hamstra, M." Language undetermined
7 results on '"Hamstra, M."'

1. Precision Measurement of the Specific Activity of $^{39}$Ar in Atmospheric Argon with the DEAP-3600 Detector

Author

Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Amaudruz, P. -A., Anstey, J., Araujo, G. R., Auty, D. J., Baldwin, M., Batygov, M., Beltran, B., Benmansour, H., Bina, C. E., Bonatt, J., Bonivento, W., Boulay, M. G., Broerman, B., Bueno, J. F., Burghardt, P. M., Butcher, A., Cadeddu, M., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, M., Chen, Y., Choudhary, S., Cleveland, B. T., Corning, J. M., Crampton, R., Cranshaw, D., Daughtery, S., DelGobbo, P., Dering, K., Di Stefano, P., DiGioseffo, J., Dolganov, G., Doria, L., Duncan, F. A., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Florian, S., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., Abia, P. García, Garg, S., Giampa, P., Giménez-Alcázar, A., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Haskins, S., Hearns, C., Hu, J., Hucker, J., Hugues, T., Ilyasov, A., Jigmeddorj, B., Jillings, C. J., Joy, A., Kamaev, O., Kaur, G., Kemp, A., Kuźniak, M., La Zia, F., Lai, M., Langrock, S., Lehnert, B., Leonhardt, A., LePage-Bourbonnais, J., Levashko, N., Lidgard, J., Lindner, T., Lissia, M., Lock, J., Machulin, I., Majewski, P., Maru, A., Mason, J., McDonald, A. B., McElroy, T., McGinn, T., McLaughlin, J. B., Mehdiyev, R., Mielnichuk, C., Mirasola, L., Monroe, J., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., O'Dwyer, E., Oliviéro, G., Ouellet, C., Pal, S., Papi, D., Pasuthip, P., Peeters, S. J. M., Perry, M., Pesudo, V., Picciau, E., Piro, M. -C., Pollmann, T. R., Rad, F., Rand, E. T., Rethmeier, C., Retière, F., García, I. Rodríguez, Roszkowski, L., Ruhland, J. B., Santorelli, R., Schuckman II, F. G., Seeburn, N., Seth, S., Shalamova, V., Singhrao, K., Skensved, P., Smith, N. J. T., Smith, B., Sobotkiewich, K., Sonley, T., Sosiak, J., Soukup, J., Stainforth, R., Stone, C., Strickland, V., Stringer, M., Sur, B., Tang, J., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Vyas, B., Walczak, M., Walding, J., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.

Subjects
High Energy Physics - Experiment (hep-ex), Physics - Instrumentation and Detectors, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), High Energy Physics - Experiment
Abstract

The specific activity of the beta decay of $^{39}$Ar in atmospheric argon is measured using the DEAP-3600 detector. DEAP-3600, located 2 km underground at SNOLAB, uses a total of (3269 $\pm$ 24) kg of liquid argon distilled from the atmosphere to search for dark matter. This detector with very low background uses pulseshape discrimination to differentiate between nuclear recoils and electron recoils and is well-suited to measure the decay of $^{39}$Ar. With 167 live-days of data, the measured specific activity at the time of atmospheric extraction is [0.964 $\pm$ 0.001 (stat) $\pm$ 0.024 (sys)] Bq/kg$_{\rm atmAr}$ which is consistent with results from other experiments. A cross-check analysis using different event selection criteria provides a consistent result.

Published
2023
Full Text
View/download PDF

2. First Direct Detection Constraints on Planck-Scale Mass Dark Matter with Multiple-Scatter Signatures Using the DEAP-3600 Detector

Author

Adhikari, P., Ajaj, R., Alp��zar-Venegas, M., Auty, D. J., Benmansour, H., Bina, C. E., Bonivento, W., Boulay, M. G., Cadeddu, M., Cai, B., C��rdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S., DelGobbo, P., Di Stefano, P., Doria, L., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Gallacher, D., Abia, P. Garc��a, Garg, S., Giampa, P., Goeldi, D., Gorel, P., Graham, K., Grobov, A., Hallin, A. L., Hamstra, M., Hugues, T., Ilyasov, A., Joy, A., Jigmeddorj, B., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Ku{��}niak, M., Lai, M., Langrock, S., Lehnert, B., Leonhardt, A., Levashko, N., Li, X., Lissia, M., Litvinov, O., Lock, J., Longo, G., Machulin, I., McDonald, A. B., McElroy, T., McLaughlin, J. B., Mielnichuk, C., Mirasola, L., Monroe, J., Olivi��ro, G., Pal, S., Peeters, S. J. M., Perry, M., Pesudo, V., Picciau, E., Piro, M. -C., Pollmann, T. R., Raj, N., Rand, E. T., Rethmeier, C., Reti��re, F., Rodr��guez-Garc��a, I., Roszkowski, L., Ruhland, J. B., Garc��a, E. Sanchez, S��nchez-Pastor, T., Santorelli, R., Seth, S., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stringer, M., Sur, B., V��zquez-J��uregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., Zu��iga-Reyes, A., Adhikari, P., Ajaj, R., Alpizar-Venegas, M., Auty, D., Benmansour, H., Bina, C., Bonivento, W., Boulay, M., Cadeddu, M., Cai, B., Cardenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B., Corning, J., Daugherty, S., Delgobbo, P., Di Stefano, P., Doria, L., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S., Fatemighomi, N., Fiorillo, G., Gallacher, D., Garcia Abia, P., Garg, S., Giampa, P., Goeldi, D., Gorel, P., Graham, K., Grobov, A., Hallin, A., Hamstra, M., Hugues, T., Ilyasov, A., Joy, A., Jigmeddorj, B., Jillings, C., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuzniak, M., Lai, M., Langrock, S., Lehnert, B., Leonhardt, A., Levashko, N., Li, X., Lissia, M., Litvinov, O., Lock, J., Longo, G., Machulin, I., Mcdonald, A. B., Mcelroy, T., Mclaughlin, J., Mielnichuk, C., Mirasola, L., Monroe, J., Oliviero, G., Pal, S., Peeters, S., Perry, M., Pesudo, V., Picciau, E., Piro, M. -C., Pollmann, T. R., Raj, N., Rand, E., Rethmeier, C., Retiere, F., Rodriguez-Garcia, I., Roszkowski, L., Ruhland, J. B., Sanchez Garcia, E., Sanchez-Pastor, T., Santorelli, R., Seth, S., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stringer, M., Sur, B., Vazquez-Jauregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuniga-Reyes, A.

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010308 nuclear & particles physics, General Physics and Astronomy, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, 010306 general physics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Dark matter particles with Planck-scale mass ($\simeq10^{19}\text{GeV}/c^2$) arise in well-motivated theories and could be produced by several cosmological mechanisms. Using a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based dark matter experiment at SNOLAB, a search for supermassive dark matter was performed, looking for multiple-scatter signals. No candidate signal events were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between $8.3\times10^{6}$ and $1.2\times10^{19} \text{GeV}/c^2$, and cross sections for scattering on $^{40}$Ar between $1.0\times10^{-23}$ and $2.4\times10^{-18} \text{cm}^2$. These are used to constrain two composite dark matter models.

Published
2021

3. In-situ characterization of the Hamamatsu R5912-HQE photomultiplier tubes used in the DEAP-3600 experiment

Author

Amaudruz, PA, Batygov, M, Beltran, B, Bina, CE, Bishop, D, Bonatt, J, Boorman, G, Boulay, MG, Broerman, B, Bromwich, T, Bueno, JF, Butcher, A, Cai, B, Chan, S, Chen, M, Chouinard, R, Churchwell, S, Cleveland, BT, Cranshaw, D, Dering, K, Dittmeier, S, Duncan, FA, Dunford, M, Erlandson, A, Fatemighomi, N, Ford, RJ, Gagnon, R, Giampa, P, Golovko, VV, Gorel, P, Gornea, R, Grace, E, Graham, K, Grant, DR, Gulyev, E, Hall, A, Hallin, AL, Hamstra, M, Harvey, PJ, Hearns, C, Jillings, CJ, Kamaev, O, Kemp, A, Kuźniak, M, Langrock, S, La Zia, F, Lehnert, B, Li, O, Lidgard, JJ, Liimatainen, P, Lim, C, Lindner, T, Linn, Y, Liu, S, Mathew, R, McDonald, AB, McElroy, T, McFarlane, K, McLaughlin, J, Mead, S, Mehdiyev, R, Mielnichuk, C, Monroe, J, Muir, A, Nadeau, P, Nantais, C, Ng, C, Noble, AJ, O'Dwyer, E, Ohlmann, C, Olchanski, K, Olsen, KS, Ouellet, C, Pasuthip, P, Peeters, SJM, Pollmann, TR, Rand, ET, Rau, W, Rethmeier, C, Retière, F, Seeburn, N, Shaw, B, Singhrao, K, Skensved, P, Smith, B, Smith, NJT, Sonley, T, Stainforth, R, Stone, C, Strickland, V, Sur, B, Tang, J, Taylor, J, Veloce, L, Vázquez-Jáuregui, E, Walding, J, Ward, M, Westerdale, S, White, R, and Woolsey, E

Subjects
Afterpulsing, Physics::Instrumentation and Detectors, Late and double pulsing, Molecular, Dark matter detection, PMT, Atomic, Nuclear & Particles Physics, Dark noise, Other Physical Sciences, Hamamatsu R5912-HQE, Particle and Plasma Physics, Single photoelectron charge distribution, Nuclear, physics.ins-det, Astronomical and Space Sciences
Abstract

The Hamamatsu R5912-HQE photomultiplier-tube (PMT) is a novel high-quantum efficiency PMT. It is currently used in the DEAP-3600 dark matter detector and is of significant interest for future dark matter and neutrino experiments where high signal yields are needed. We report on the methods developed for in-situ characterization and monitoring of DEAP's 255 R5912-HQE PMTs. This includes a detailed discussion of typical measured single-photoelectron charge distributions, correlated noise (afterpulsing), dark noise, double, and late pulsing characteristics. The characterization is performed during the detector commissioning phase using laser light injected through a light diffusing sphere and during normal detector operation using LED light injected through optical fibres.

Published
2019

4. Design and construction of the DEAP-3600 dark matter detector

Author

Amaudruz, PA, Baldwin, M, Batygov, M, Beltran, B, Bina, CE, Bishop, D, Bonatt, J, Boorman, G, Boulay, MG, Broerman, B, Bromwich, T, Bueno, JF, Burghardt, PM, Butcher, A, Cai, B, Chan, S, Chen, M, Chouinard, R, Churchwell, S, Cleveland, BT, Cranshaw, D, Dering, K, DiGioseffo, J, Dittmeier, S, Duncan, FA, Dunford, M, Erlandson, A, Fatemighomi, N, Florian, S, Flower, A, Ford, RJ, Gagnon, R, Giampa, P, Golovko, VV, Gorel, P, Gornea, R, Grace, E, Graham, K, Grant, DR, Gulyev, E, Hall, A, Hallin, AL, Hamstra, M, Harvey, PJ, Hearns, C, Jillings, CJ, Kamaev, O, Kemp, A, Kuźniak, M, Langrock, S, La Zia, F, Lehnert, B, Li, O, Lidgard, JJ, Liimatainen, P, Lim, C, Lindner, T, Linn, Y, Liu, S, Majewski, P, Mathew, R, McDonald, AB, McElroy, T, McFarlane, K, McGinn, T, McLaughlin, JB, Mead, S, Mehdiyev, R, Mielnichuk, C, Monroe, J, Muir, A, Nadeau, P, Nantais, C, Ng, C, Noble, AJ, O'Dwyer, E, Ohlmann, C, Olchanski, K, Olsen, KS, Ouellet, C, Pasuthip, P, Peeters, SJM, Pollmann, TR, Rand, ET, Rau, W, Rethmeier, C, Retière, F, Seeburn, N, Shaw, B, Singhrao, K, Skensved, P, Smith, B, Smith, NJT, Sonley, T, Soukup, J, Stainforth, R, Stone, C, Strickland, V, Sur, B, and Tang, J

Subjects
Physics::Instrumentation and Detectors, WIMP, hep-ex, Astrophysics::Instrumentation and Methods for Astrophysics, Liquid Argon, DEAP, Molecular, Astrophysics::Cosmology and Extragalactic Astrophysics, SNOLAB, Atomic, Nuclear & Particles Physics, Particle and Plasma Physics, Dark matter, Nuclear, Astronomical and Space Sciences, Low background, astro-ph.IM
Abstract

The Dark matter Experiment using Argon Pulse-shape discrimination (DEAP) has been designed for a direct detection search for particle dark matter using a single-phase liquid argon target. The projected cross section sensitivity for DEAP-3600 to the spin-independent scattering of Weakly Interacting Massive Particles (WIMPs) on nucleons is 10−46cm2 for a 100 GeV/c2 WIMP mass with a fiducial exposure of 3 tonne-years. This paper describes the physical properties and construction of the DEAP-3600 detector.

Published
2019

5. DEAP-3600 Dark Matter Search

Author

DEAP Collaboration, Amaudruz, P. -A., Batygov, M., Beltran, B., Bonatt, J., Boulay, M. G., Broerman, B., Bueno, J. F., Butcher, A., Cai, B., Chen, M., Chouinard, R., Cleveland, B. T., Dering, K., DiGioseffo, J., Duncan, F., Flower, T., Ford, R., Giampa, P., Gorel, P., Graham, K., Grant, D. R., Guliyev, E., Hallin, A. L., Hamstra, M., Harvey, P., Jillings, C. J., Kuźniak, M., Lawson, I., Li, O., Liimatainen, P., Majewski, P., McDonald, A. B., McElroy, T., McFarlane, K., Monroe, J., Muir, A., Nantais, C., Ng, C., Noble, A. J., Ouellet, C., Palladino, K., Pasuthip, P., Peeters, S. J. M., Pollmann, T., Rau, W., Retière, F., Seeburn, N., Singhrao, K., Skensved, P., Smith, B., Sonley, T., Tang, J., Vázquez-Jáuregui, E., Veloce, L., Walding, J., and Ward, M.

Subjects
Nuclear and High Energy Physics, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Physics - Instrumentation and Detectors, WIMP, Dark matter, DEAP, FOS: Physical sciences, SNOLAB, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Dark Matter, low radioactivity techniques, Sensitivity (control systems), 010306 general physics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Physics, 010308 nuclear & particles physics, Scattering, ultra-low backgrounds, Detector, Instrumentation and Detectors (physics.ins-det), liquid argon, underground physics, Weakly interacting massive particles, liquid noble gas detectors, Astrophysics - Instrumentation and Methods for Astrophysics, Nucleon, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The DEAP-3600 experiment is located 2 km underground at SNOLAB, in Sudbury, Ontario. It is a single-phase detector that searches for dark matter particle interactions within a 1000-kg fiducial mass target of liquid argon. A first generation prototype detector (DEAP-1) with a 7-kg liquid argon target mass demonstrated a high level of pulse-shape discrimination (PSD) for reducing $\beta$/$\gamma$ backgrounds and helped to develop low radioactivity techniques to mitigate surface-related $\alpha$ backgrounds. Construction of the DEAP-3600 detector is nearly complete and commissioning is starting in 2014. The target sensitivity to spin-independent scattering of Weakly Interacting Massive Particles (WIMPs) on nucleons of 10$^{-46}$ cm$^2$ will allow one order of magnitude improvement in sensitivity over current searches at 100 GeV WIMP mass. This paper presents an overview and status of the DEAP-3600 project and discusses plans for a future multi-tonne experiment, DEAP-50T., Comment: International Conference on High Energy Physics (ICHEP 2014), Valencia, 2014

Published
2016

6. The DEAP-3600 Experiment

Author

Stringer, M., Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Auty, D. J., Benmansour, H., Bina, C. E., Bonivento, W., Boulay, M. G., Matteo Cadeddu, Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S., Delgobbo, P., Di Stefano, P., Doria, L., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Gorel, P., Graham, K., Grobov, A., Hallin, A. L., Hamstra, M., Hugues, T., Ilyasov, A., Joy, A., Jigmeddorj, B., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Lai, M., Langrock, S., Lehnert, B., Leonhardt, A., Levashko, N., Li, X., Lissia, M., Litvinov, O., Lock, J., Longo, G., Machulin, I., Mcdonald, A. B., Mcelroy, T., Mclaughlin, J. B., Mielnichuk, C., Mirasola, L., Monroe, J., Oliviéro, G., Pal, S., Peeters, S. J. M., Perry, M., Pesudo, V., Picciau, E., Piro, M. -C, Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Rodríguez-García, I., Roszkowski, L., Ruhland, J. B., Sanchez García, E., Sánchez-Pastor, T., Santorelli, R., Seth, S., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Sur, B., Vázquez-Jáuregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.

7. Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector

Author

C. Rethmeier, Laurelle Maria Veloce, C. Jillings, C. E. Bina, S. Langrock, T. Sonley, C. M. Nantais, Stefano Cavuoti, Peter Majewski, M. C. Piro, V. V. Golovko, K. Graham, N. J. T. Smith, O. Litvinov, P. Skensved, J. B. McLaughlin, Darren Grant, E. Sanchez Garcia, P. Nadeau, O. Kamaev, I. Kochanek, M. G. Boulay, Min Chen, Martin Ward, D. Gallacher, R. J. Ford, J. Lock, A. Zuñiga-Reyes, F. La Zia, N. Fatemighomi, Giuseppe Longo, T. McGinn, S. Viel, A. B. McDonald, Y. Chen, M. Hamstra, P. J. Harvey, A. Erlandson, D. Goeldi, B. Lehnert, V. Pesudo, N. Seeburn, V. Strickland, E. T. Rand, S. Garg, R. Gagnon, K. Dering, C. Mielnichuk, R. Santorelli, Bhaskar Sur, P. Pasuthip, T. McElroy, A. J. Noble, P. Gorel, Xiujiang Li, S. J. M. Peeters, R. Ajaj, B. Beltran, A. Flower, C. Ng, Jocelyn Monroe, A. Joy, J. Walding, M. Waqar, A. Kemp, G. Kaur, J. Willis, M. Batygov, C. Hearns, T. Pollmann, J. F. Bueno, G. R. Araujo, R. Mehdiyev, A. L. Hallin, G. Fiorillo, B. T. Cleveland, F. Retiere, Miguel Cárdenas-Montes, B. C. Smith, M. Kuźniak, C. Stone, S. Westerdale, F. A. Duncan, R. Stainforth, B. Broerman, A. Butcher, Bei Cai, C. Ouellet, M. Dunford, E. Vázquez-Jáuregui, P. M. Burghardt, P. Giampa, P. Garcia Abia, 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.

Subjects
Dark matter, Analytical chemistry, FOS: Physical sciences, nucl-ex, 01 natural sciences, Atomic, DEAP, Particle and Plasma Physics, 0103 physical sciences, Nuclear, Nuclear Experiment (nucl-ex), Single phase, 010306 general physics, Nuclear Experiment, Instrumentation and Methods for Astrophysics (astro-ph.IM), ComputingMilieux_MISCELLANEOUS, QC, Prior information, Physics, Quantum Physics, 010308 nuclear & particles physics, Molecular, Nuclear & Particles Physics, Liquid argon, Astrophysics - Instrumentation and Methods for Astrophysics, Astronomical and Space Sciences, astro-ph.IM
Abstract

Author(s): Ajaj, R; Araujo, GR; Batygov, M; Beltran, B; Bina, CE; Boulay, MG; Broerman, B; Bueno, JF; Burghardt, PM; Butcher, A; Cai, B; Cardenas-Montes, M; Cavuoti, S; Chen, M; Chen, Y; Cleveland, BT; Dering, K; Duncan, FA; Dunford, M; Erlandson, A; Fatemighomi, N; Fiorillo, G; Flower, A; Ford, RJ; Gagnon, R; Gallacher, D; Garcia Abia, P; Garg, S; Giampa, P; Goeldi, D; Golovko, VV; Gorel, P; Graham, K; Grant, DR; Hallin, AL; Hamstra, M; Harvey, PJ; Hearns, C; Joy, A; Jillings, CJ; 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, AB; McElroy, T; McGinn, T; McLaughlin, JB; Mehdiyev, R; Mielnichuk, C; Monroe, J; Nadeau, P; Nantais, C; Ng, C; Noble, AJ; Ouellet, C; Pasuthip, P; Peeters, SJM; Pesudo, V; Piro, MC; Pollmann, TR; Rand, ET; Rethmeier, C; Retiere, F; Sanchez Garcia, E; Santorelli, R; Seeburn, N; Skensved, P; Smith, B; Smith, NJT; Sonley, T; Stainforth, R; Stone, C; Strickland, V; Sur, B; Vazquez-Jauregui, E | Abstract: The DEAP-3600 experiment is searching for weakly interacting massive particles dark matter with a 3.3 ×103 kg 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 Ar40 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 Ar42 in LAr in DEAP-3600 is determined by measuring the daughter decay of K42. 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 Ar42 in the atmosphere is found to be 40.4±5.9 μBq/kg of argon.

Published
2019

Catalog

Books, media, physical & digital resources
See catalog results