Author: "Hamstra, M." - Searchworks@Jio Institute Digital Library Search Results

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1. Relative Measurement and Extrapolation of the Scintillation Quenching Factor of $\alpha$-Particles in Liquid Argon using DEAP-3600 Data

Author: The DEAP Collaboration, Adhikari, P., Alpízar-Venegas, M., Amaudruz, P. -A., Anstey, J., Auty, D. J., Batygov, M., Beltran, B., Bina, C. E., Bonivento, W., Boulay, M. G., Bueno, J. F., Cai, B., Cárdenas-Montes, M., Choudhary, S., Cleveland, B. T., Crampton, R., Daugherty, S., DelGobbo, P., Di Stefano, P., Dolganov, G., Doria, L., Duncan, F. A., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Ford, R. J., Gahan, D., Gallacher, D., Abia, P. García, Garg, S., Giampa, P., Giménez-Alcázar, A., Goeldi, D., Gorel, P., Graham, K., Hallin, A. L., Hamstra, M., Haskins, S., Hu, J., Hucker, J., Hugues, T., Ilyasov, A., Jigmeddorj, B., Jillings, C. J., Kaur, G., Kemp, A., Kuźniak, M., La Zia, F., Lai, M., Langrock, S., Lehnert, B., Levashko, N., Lissia, M., Luzzi, L., Machulin, I., Maru, A., Mason, J., McDonald, A. B., McElroy, T., McLaughlin, J. B., Mielnichuk, C., Mirasola, L., Monroe, J., Ng, C., Oliviéro, G., Pal, S., Papi, D., Perry, M., Pesudo, V., Pollmann, T. R., Rad, F., Rethmeier, C., Retière, F., Roszkowski, L., Santorelli, R., Schuckman II, F. G., Seth, S., Shalamova, V., Skensved, P., Smirnova, T., Sobotkiewich, K., Sonley, T., Sosiak, J., Soukup, J., Stainforth, R., Stringer, M., Tang, J., Vázquez-Jáuregui, E., Viel, S., Vyas, B., Walczak, M., Walding, J., Ward, M., and Westerdale, S.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: The knowledge of scintillation quenching of $\alpha$-particles plays a paramount role in understanding $\alpha$-induced backgrounds and improving the sensitivity of liquid argon-based direct detection of dark matter experiments. We performed a relative measurement of scintillation quenching in the MeV energy region using radioactive isotopes ($^{222}$Rn, $^{218}$Po and $^{214}$Po isotopes) present in trace amounts in the DEAP-3600 detector and quantified the uncertainty of extrapolating the quenching factor to the low-energy region., Comment: Submitted to Eur. Phys. J. C
Published: 2024

2. 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: Physics - Instrumentation and Detectors, 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
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3. First direct detection constraints on Planck-scale mass dark matter with multiple-scatter signatures using the DEAP-3600 detector

Author: Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Auty, D. J., Benmansour, H., Bina, C. E., Bonivento, W., Boulay, M. G., Cadeddu, M., 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., Abia, P. García, 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{ź}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., Oliviéro, 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., Retière, F., Rodríguez-García, I., Roszkowski, L., Ruhland, J. B., García, E. Sanchez, Sánchez-Pastor, T., Santorelli, R., Seth, S., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stringer, M., Sur, B., Vázquez-Jáuregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, High Energy Physics - Phenomenology
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
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4. Pulseshape discrimination against low-energy Ar-39 beta decays in liquid argon with 4.5 tonne-years of DEAP-3600 data

Author: The DEAP Collaboration, Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Amaudruz, P. -A., Auty, D. J., 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., Cleveland, B. T., Corning, J. M., Cranshaw, D., Daugherty, S., DelGobbo, P., Dering, K., DiGioseffo, J., Di Stefano, P., Doria, L., Duncan, F. A., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Florian, S., Flower, T., Ford, R. J., Gagnon, R., Gallacher, D., Abia, P. García, Garg, S., Giampa, P., Goeldi, D., Golovko, V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., 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., Lidgard, J., Lindner, T., Lissia, M., Lock, J., Longo, G., Machulin, I., 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., O'Dwyer, E., Oliviéro, G., Ouellet, C., Pal, S., Pasuthip, P., 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., Sánchez-García, E., Santorelli, R., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Soukup, J., Stainforth, R., Stone, C., Strickland, V., Stringer, M., Sur, B., Tang, J., Vázquez-Jáuregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Subjects: Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from $^{39}$Ar beta decays and is suppressed using pulseshape discrimination (PSD). We use two types of PSD algorithm: the prompt-fraction, which considers the fraction of the scintillation signal in a narrow and a wide time window around the event peak, and the log-likelihood-ratio, which compares the observed photon arrival times to a signal and a background model. We furthermore use two algorithms to determine the number of photons detected at a given time: (1) simply dividing the charge of each PMT pulse by the charge of a single photoelectron, and (2) a likelihood analysis that considers the probability to detect a certain number of photons at a given time, based on a model for the scintillation pulseshape and for afterpulsing in the light detectors. The prompt-fraction performs approximately as well as the log-likelihood-ratio PSD algorithm if the photon detection times are not biased by detector effects. We explain this result using a model for the information carried by scintillation photons as a function of the time when they are detected., Comment: 14 pages, 9 figures
Published: 2021
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5. Constraints on dark matter-nucleon effective couplings in the presence of kinematically distinct halo substructures using the DEAP-3600 detector

Author: Adhikari, P., Ajaj, R., Bina, C. E., Bonivento, W., Boulay, M. G., Cadeddu, M., 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., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Gallacher, D., Garcés, E. A., Abia, P. García, 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., Levashko, N., Li, X., Litvinov, O., Lock, J., Longo, G., Machulin, I., McDonald, A. B., McElroy, T., McLaughlin, J. B., Mielnichuk, C., Monroe, J., Oliviéro, G., Pal, S., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Roszkowski, L., García, E. Sanchez, Sánchez-Pastor, T., Santorelli, R., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stringer, M., Sur, B., Vázquez-Jáuregui, E., Viel, S., Vincent, A. C., Walding, J., Waqar, M., Westerdale, S., and Zuñiga-Reyes, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: DEAP-3600 is a single-phase liquid argon detector aiming to directly detect Weakly Interacting Massive Particles (WIMPs), located at SNOLAB (Sudbury, Canada). After analyzing data taken during the first year of operation, a null result was used to place an upper bound on the WIMP-nucleon spin-independent, isoscalar cross section. This study reinterprets this result within a Non-Relativistic Effective Field Theory framework, and further examines how various possible substructures in the local dark matter halo may affect these constraints. Such substructures are hinted at by kinematic structures in the local stellar distribution observed by the Gaia satellite and other recent astronomical surveys. These include the Gaia Sausage (or Enceladus), as well as a number of distinct streams identified in recent studies. Limits are presented for the coupling strength of the effective contact interaction operators $\mathcal{O}_1$, $\mathcal{O}_3$, $\mathcal{O}_5$, $\mathcal{O}_8$, and $\mathcal{O}_{11}$, considering isoscalar, isovector, and xenonphobic scenarios, as well as the specific operators corresponding to millicharge, magnetic dipole, electric dipole, and anapole interactions. The effects of halo substructures on each of these operators are explored as well, showing that the $\mathcal{O}_5$ and $\mathcal{O}_8$ operators are particularly sensitive to the velocity distribution, even at dark matter masses above 100 GeV/$c^2$.
Published: 2020
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6. The liquid-argon scintillation pulseshape in DEAP-3600

Author: The DEAP collaboration, Adhikari, P., Ajaj, R., Batygov, G. R. Araujoand M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Dering, S. J. Daughertyand K., Doria, L., Dunford, F. A. Duncan andM., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., Garcés, E. A., Abia, P. García, Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Ilyasov, A., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Levashko, N., Li, X., Litvinov, O., Lock, J., Longo, G., Machulin, I., 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., Oliviéro, G., Ouellet, C., Pal, S., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., García, E. Sanchez, Sánchez-Pastor, T., 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: Physics - Instrumentation and Detectors
Abstract: DEAP-3600 is a liquid-argon scintillation detector looking for dark matter. Scintillation events in the liquid argon (LAr) are registered by 255 photomultiplier tubes (PMTs), and pulseshape discrimination (PSD) is used to suppress electromagnetic background events. The excellent PSD performance of LAr makes it a viable target for dark matter searches, and the LAr scintillation pulseshape discussed here is the basis of PSD. The observed pulseshape is a combination of LAr scintillation physics with detector effects. We present a model for the pulseshape of electromagnetic background events in the energy region of interest for dark matter searches. The model is composed of a) LAr scintillation physics, including the so-called intermediate component, b) the time response of the TPB wavelength shifter, including delayed TPB emission at $\mathcal O$(ms) time-scales, and c) PMT response. TPB is the wavelength shifter of choice in most LAr detectors. We find that approximately 10\% of the intensity of the wavelength-shifted light is in a long-lived state of TPB. This causes light from an event to spill into subsequent events to an extent not usually accounted for in the design and data analysis of LAr-based detectors.
Published: 2020
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7. Electromagnetic Backgrounds and Potassium-42 Activity in the DEAP-3600 Dark Matter Detector

Author: 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., 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., Gallacher, D., Abia, P. García, 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., García, E. Sanchez, 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: Nuclear Experiment, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The DEAP-3600 experiment is searching for WIMP dark matter with a 3.3 tonne single phase liquid argon (LAr) target, located 2.1 km underground at SNOLAB. The experimental signature of dark matter interactions is keV-scale $^{40}$Ar nuclear recoils (NR) producing 128 nm LAr scintillation photons observed by PMTs. The largest backgrounds in DEAP-3600 are electronic recoils (ER) induced by $\beta$ and $\gamma$-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. While excellent discrimination between ERs and NRs is reached with pulse shape discrimination, utilizing the large difference between fast and slow components of LAr scintillation light, detailed knowledge of the ER background and activity of detector components, sets valuable constraints on other key types of backgrounds in the detector: 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. 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 $40.4 \pm 5.9$ $\mu$Bq/kg of argon.
Published: 2019
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8. Search for dark matter with a 231-day exposure of liquid argon using DEAP-3600 at SNOLAB

Author: Ajaj, R., Amaudruz, P. -A., Araujo, G. R., Baldwin, M., Batygov, M., Beltran, B., Bina, C. E., Bonatt, J., Boulay, M. G., Broerman, B., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Cavuoti, S., Chen, M., Chen, Y., Cleveland, B. T., Cranshaw, D., Dering, K., DiGioseffo, J., Doria, L., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Florian, S., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., Garcés, E. A., 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., Lidgard, J., Lindner, T., 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., O'Dwyer, E., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Seeburn, N., Singhrao, K., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Soukup, J., Stainforth, R., Stone, C., Strickland, V., Sur, B., Tang, J., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Nuclear Experiment
Abstract: DEAP-3600 is a single-phase liquid argon (LAr) direct-detection dark matter experiment, operating 2 km underground at SNOLAB (Sudbury, Canada). The detector consists of 3279 kg of LAr contained in a spherical acrylic vessel. This paper reports on the analysis of a 758 tonne\cdot day exposure taken over a period of 231 live-days during the first year of operation. No candidate signal events are observed in the WIMP-search region of interest, which results in the leading limit on the WIMP-nucleon spin-independent cross section on a LAr target of $3.9\times10^{-45}$ cm$^{2}$ ($1.5\times10^{-44}$ cm$^{2}$) for a 100 GeV/c$^{2}$ (1 TeV/c$^{2}$) WIMP mass at 90\% C. L. In addition to a detailed background model, this analysis demonstrates the best pulse-shape discrimination in LAr at threshold, employs a Bayesian photoelectron-counting technique to improve the energy resolution and discrimination efficiency, and utilizes two position reconstruction algorithms based on PMT charge and photon arrival times.
Published: 2019
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9. Electromagnetic backgrounds and potassium-42 activity in the DEAP-3600 dark matter detector

Author: Ajaj, R, Araujo, GR, Batygov, M, Beltran, B, Bina, CE, Boulay, MG, Broerman, B, Bueno, JF, Burghardt, PM, Butcher, A, Cai, B, Cárdenas-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, García 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, Retière, F, Sanchez García, E, Santorelli, R, Seeburn, N, Skensved, P, Smith, B, Smith, NJT, 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: nucl-ex, astro-ph.IM
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

10. Design and Construction of the DEAP-3600 Dark Matter Detector

Author: Amaudruz, P. -A., Baldwin, M., Batygov, M., Beltran, B., Bina, C. E., Bishop, D., Bonatt, J., Boorman, G., Boulay, M. G., Broerman, B., Bromwich, T., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Chan, S., Chen, M., Chouinard, R., Churchwell, S., Cleveland, B. T., Cranshaw, D., Dering, K., DiGioseffo, J., Dittmeier, S., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Florian, S., Flower, A., Ford, R. J., Gagnon, R., Giampa, P., Golovko, V. V., Gorel, P., Gornea, R., Grace, E., Graham, K., Grant, D. R., Gulyev, E., Hall, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Jillings, C. J., Kamaev, O., Kemp, A., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, O., Lidgard, J. J., Liimatainen, P., Lim, C., Lindner, T., Linn, Y., Liu, S., Majewski, P., Mathew, R., McDonald, A. B., McElroy, T., McFarlane, K., McGinn, T., McLaughlin, J. B., Mead, S., Mehdiyev, R., Mielnichuk, C., Monroe, J., Muir, A., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., O'Dwyer, E., Ohlmann, C., Olchanski, K., Olsen, K. S., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pollmann, T. R., Rand, E. T., Rau, W., Rethmeier, C., Retière, F., Seeburn, N., Shaw, B., Singhrao, K., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Soukup, J., 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., Woolsey, E., and Zielinski, J.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
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 $10^{-46}~\rm{cm}^{2}$ for a 100 GeV/$c^2$ WIMP mass with a fiducial exposure of 3 tonne-years. This paper describes the physical properties and construction of the DEAP-3600 detector., Comment: minor corrections in version 2. 70 pages, 24 figures, to be submitted to Astroparticle Physics Journal
Published: 2017
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11. In-situ characterization of the Hamamatsu R5912-HQE photomultiplier tubes used in the DEAP-3600 experiment

Author: Amaudruz, P-A, 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: Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, PMT, Hamamatsu R5912-HQE, Single photoelectron charge distribution, Afterpulsing, Late and double pulsing, Dark noise, Dark matter detection, physics.ins-det, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Nuclear & Particles Physics, Nuclear and plasma physics
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

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

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

Author: Amaudruz, P-A, 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: Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, Dark matter, WIMP, Liquid Argon, DEAP, SNOLAB, Low background, astro-ph.IM, hep-ex, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics, Astronomical sciences, Particle and high energy physics
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

14. 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: Dark matter, WIMP, Liquid Argon, DEAP, SNOLAB, Low background, astro-ph.IM, hep-ex, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
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

15. First results from the DEAP-3600 dark matter search with argon at SNOLAB

Author: Collaboration, DEAP-3600, Amaudruz, P. -A., Baldwin, M., Batygov, M., Beltran, B., Bina, C. E., Bishop, D., Bonatt, J., Boorman, G., Boulay, M. G., Broerman, B., Bromwich, T., Bueno, J. F., Burghardt, P. M., Butcher, A., Cai, B., Chan, S., Chen, M., Chouinard, R., Cleveland, B. T., Cranshaw, D., Dering, K., DiGioseffo, J., Dittmeier, S., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Florian, S., Flower, A., Ford, R. J., Gagnon, R., Giampa, P., Golovko, V. V., Gorel, P., Gornea, R., Grace, E., Graham, K., Gulyev, E., Hakobyan, R., Hall, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Jillings, C. J., Kamaev, O., Kemp, A., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Lidgard, J. J., Lim, C., Lindner, T., Linn, Y., Liu, S., Majewski, P., Mathew, R., McDonald, A. B., McElroy, T., McGinn, T., McLaughlin, J. B., Mead, S., Mehdiyev, R., Mielnichuk, C., Monroe, J., Muir, A., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., O'Dwyer, E., Ohlmann, C., Olchanski, K., Olsen, K. S., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pollmann, T. R., Rand, E. T., Rau, W., Rethmeier, C., Retière, F., Seeburn, N., Shaw, B., Singhrao, K., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Soukup, J., Stainforth, R., Stone, C., Strickland, V., Sur, B., Tang, J., Taylor, J., Veloce, L., Vázquez-Jáuregui, E., Walding, J., Ward, M., Westerdale, S., Woolsey, E., and Zielinski, J.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: This paper reports the first results of a direct dark matter search with the DEAP-3600 single-phase liquid argon (LAr) detector. The experiment was performed 2 km underground at SNOLAB (Sudbury, Canada) utilizing a large target mass, with the LAr target contained in a spherical acrylic vessel of 3600 kg capacity. The LAr is viewed by an array of PMTs, which would register scintillation light produced by rare nuclear recoil signals induced by dark matter particle scattering. An analysis of 4.44 live days (fiducial exposure of 9.87 tonne-days) of data taken with the nearly full detector during the initial filling phase demonstrates the detector performance and the best electronic recoil rejection using pulse-shape discrimination in argon, with leakage $<1.2\times 10^{-7}$ (90% C.L.) between 16 and 33 keV$_{ee}$. No candidate signal events are observed, which results in the leading limit on WIMP-nucleon spin-independent cross section on argon, $<1.2\times 10^{-44}$ cm$^2$ for a 100 GeV/c$^2$ WIMP mass (90% C.L.)., Comment: Accepted for publication in Physical Review Letters
Published: 2017
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16. In-situ characterization of the Hamamatsu R5912-HQE photomultiplier tubes used in the DEAP-3600 experiment

Author: DEAP Collaboration, Amaudruz, P. -A., Batygov, M., Beltran, B., Bina, C. E., Bishop, D., Bonatt, J., Boorman, G., Boulay, M. G., Broerman, B., Bromwich, T., Bueno, J. F., Butcher, A., Cai, B., Chan, S., Chen, M., Chouinard, R., Churchwell, S., Cleveland, B. T., Cranshaw, D., Dering, K., Dittmeier, S., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Ford, R. J., Gagnon, R., Giampa, P., Golovko, V. V., Gorel, P., Gornea, R., Grace, E., Graham, K., Grant, D. R., Gulyev, E., Hall, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Jillings, C. J., Kamaev, O., Kemp, A., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, O., Lidgard, J. J., Liimatainen, P., Lim, C., Lindner, T., Linn, Y., Liu, S., Mathew, R., McDonald, A. B., McElroy, T., McFarlane, K., McLaughlin, J., Mead, S., Mehdiyev, R., Mielnichuk, C., Monroe, J., Muir, A., Nadeau, P., Nantais, C., Ng, C., Noble, A. J., O'Dwyer, E., Ohlmann, C., Olchanski, K., Olsen, K. S., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pollmann, T. R., Rand, E. T., Rau, W., Rethmeier, C., Retiére, F., Seeburn, N., Shaw, B., Singhrao, K., Skensved, P., Smith, B., Smith, N. J. T., 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., Woolsey, E., and Zielinski, J.
Subjects: Physics - Instrumentation and Detectors
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: 2017
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17. 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: Physics - Instrumentation and Detectors, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
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: 2014
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18. Pulse-shape discrimination against low-energy Ar-39 beta decays in liquid argon with 4.5 tonne-years of DEAP-3600 data

Author: Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Amaudruz, P.-A., Auty, D. J., 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., Cleveland, B. T., Corning, J. M., Cranshaw, D., Daugherty, S., DelGobbo, P., Dering, K., DiGioseffo, J., Di Stefano, P., Doria, L., Duncan, F. A., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Florian, S., Flower, T., Ford, R. J., Gagnon, R., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Golovko, V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., 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., Lidgard, J., Lindner, T., Lissia, M., Lock, J., Longo, G., Machulin, I., 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., O’Dwyer, E., Oliviéro, G., Ouellet, C., Pal, S., Pasuthip, P., 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., Sánchez-García, E., Santorelli, R., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Soukup, J., Stainforth, R., Stone, C., Strickland, V., Stringer, M., Sur, B., Tang, J., Vázquez-Jáuregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Published: 2021
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19. Design and construction of the DEAP-3600 dark matter detector

Author: Amaudruz, P.-A., Baldwin, M., Batygov, M., Beltran, B., Bina, C.E., Bishop, D., Bonatt, J., Boorman, G., Boulay, M.G., Broerman, B., Bromwich, T., Bueno, J.F., Burghardt, P.M., Butcher, A., Cai, B., Chan, S., Chen, M., Chouinard, R., Churchwell, S., Cleveland, B.T., Cranshaw, D., Dering, K., DiGioseffo, J., Dittmeier, S., Duncan, F.A., Dunford, M., Erlandson, A., Fatemighomi, N., Florian, S., Flower, A., Ford, R.J., Gagnon, R., Giampa, P., Golovko, V.V., Gorel, P., Gornea, R., Grace, E., Graham, K., Grant, D.R., Gulyev, E., Hall, A., Hallin, A.L., Hamstra, M., Harvey, P.J., Hearns, C., Jillings, C.J., Kamaev, O., Kemp, A., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Li, O., Lidgard, J.J., Liimatainen, P., Lim, C., Lindner, T., Linn, Y., Liu, S., Majewski, P., Mathew, R., McDonald, A.B., McElroy, T., McFarlane, K., McGinn, T., McLaughlin, J.B., Mead, S., Mehdiyev, R., Mielnichuk, C., Monroe, J., Muir, A., Nadeau, P., Nantais, C., Ng, C., Noble, A.J., O’Dwyer, E., Ohlmann, C., Olchanski, K., Olsen, K.S., Ouellet, C., Pasuthip, P., Peeters, S.J.M., Pollmann, T.R., Rand, E.T., Rau, W., Rethmeier, C., Retière, F., Seeburn, N., Shaw, B., Singhrao, K., Skensved, P., Smith, B., Smith, N.J.T., Sonley, T., Soukup, J., 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., Woolsey, E., and Zielinski, J.
Published: 2019
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20. Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy beta and nuclear recoils in liquid argon with DEAP-1

Author: Amaudruz, P. -A., Batygov, M., Beltran, B., Bonatt, J., Boudjemline, K., Boulay, M. G., Broerman, B., Bueno, J. F., Butcher, A., Cai, B., Caldwell, T., Chen, M., Chouinard, R., Cleveland, B. T., Cranshaw, D., Dering, K., Duncan, F., Fatemighomi, N., Ford, R., Gagnon, R., Giampa, P., Giuliani, F., Gold, M., Golovko, V. V., Gorel, P., Grace, E., Graham, K., Grant, D. R., Hakobyan, R., Hallin, A. L., Hamstra, M., Harvey, P., Hearns, C., Hofgartner, J., Jillings, C. J., Kuźniak, M., Lawson, I., La Zia, F., Li, O., Lidgard, J. J., Liimatainen, P., Lippincott, W. H., Mathew, R., McDonald, A. B., McElroy, T., McFarlane, K., Mehdiyev, R., McKinsey, D. N., Monroe, J., Muir, A., Nantais, C., Nicolics, K., Nikkel, J., Noble, A. J., O'Dwyer, E., Olsen, K., Ouellet, C., Pasuthip, P., Peeters, S. J. M., Pollmann, T., Rau, W., Retière, F., Ronquest, M., Seeburn, N., Skensved, P., Smith, B., Sonley, T., Tang, J., Vázquez-Jáuregui, E., Veloce, L., Walding, J., and Ward, M.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The DEAP-1 low-background liquid argon detector was used to measure scintillation pulse shapes of electron and nuclear recoil events and to demonstrate the feasibility of pulse-shape discrimination (PSD) down to an electron-equivalent energy of 20 keV. In the surface dataset using a triple-coincidence tag we found the fraction of beta events that are misidentified as nuclear recoils to be $<1.4\times 10^{-7}$ (90% C.L.) for energies between 43-86 keVee and for a nuclear recoil acceptance of at least 90%, with 4% systematic uncertainty on the absolute energy scale. The discrimination measurement on surface was limited by nuclear recoils induced by cosmic-ray generated neutrons. This was improved by moving the detector to the SNOLAB underground laboratory, where the reduced background rate allowed the same measurement with only a double-coincidence tag. The combined data set contains $1.23\times10^8$ events. One of those, in the underground data set, is in the nuclear-recoil region of interest. Taking into account the expected background of 0.48 events coming from random pileup, the resulting upper limit on the electronic recoil contamination is $<2.7\times10^{-8}$ (90% C.L.) between 44-89 keVee and for a nuclear recoil acceptance of at least 90%, with 6% systematic uncertainty on the absolute energy scale. We developed a general mathematical framework to describe PSD parameter distributions and used it to build an analytical model of the distributions observed in DEAP-1. Using this model, we project a misidentification fraction of approx. $10^{-10}$ for an electron-equivalent energy threshold of 15 keV for a detector with 8 PE/keVee light yield. This reduction enables a search for spin-independent scattering of WIMPs from 1000 kg of liquid argon with a WIMP-nucleon cross-section sensitivity of $10^{-46}$ cm$^2$, assuming negligible contribution from nuclear recoil backgrounds., Comment: Accepted for publication in Astroparticle Physics
Published: 2009
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21. The liquid-argon scintillation pulseshape in DEAP-3600

Author: Adhikari, P., Ajaj, R., Araujo, G. R., Batygov, M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S. J., Di Stefano, P., Dering, K., Doria, L., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., Garcés , E. A., Abia, P. García, Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Ilyasov, A., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Levashko, N., Li, X., Litvinov, O., Lock, J., Longo, G., Machulin, I., 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., Oliviéro, G., Ouellet, C., Pal, S., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M.-C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., García, E. Sanchez, Sánchez-Pastor, T., Santorelli, R., Seeburn, N., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stone, C., Strickland, V., Stringer, M., Sur, B., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Published: 2020
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22. Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy β and nuclear recoils in liquid argon with DEAP-1

Author: Amaudruz, P.-A., Batygov, M., Beltran, B., Bonatt, J., Boudjemline, K., Boulay, M.G., Broerman, B., Bueno, J.F., Butcher, A., Cai, B., Caldwell, T., Chen, M., Chouinard, R., Cleveland, B.T., Cranshaw, D., Dering, K., Duncan, F., Fatemighomi, N., Ford, R., Gagnon, R., Giampa, P., Giuliani, F., Gold, M., Golovko, V.V., Gorel, P., Grace, E., Graham, K., Grant, D.R., Hakobyan, R., Hallin, A.L., Hamstra, M., Harvey, P., Hearns, C., Hofgartner, J., Jillings, C.J., Kuźniak, M., Lawson, I., La Zia, F., Li, O., Lidgard, J.J., Liimatainen, P., Lippincott, W.H., Mathew, R., McDonald, A.B., McElroy, T., McFarlane, K., McKinsey, D.N., Mehdiyev, R., Monroe, J., Muir, A., Nantais, C., Nicolics, K., Nikkel, J., Noble, A.J., O’Dwyer, E., Olsen, K., Ouellet, C., Pasuthip, P., Peeters, S.J.M., Pollmann, T., Rau, W., Retière, F., Ronquest, M., Seeburn, N., Skensved, P., Smith, B., Sonley, T., Tang, J., Vázquez-Jáuregui, E., Veloce, L., Walding, J., and Ward, M.
Published: 2016
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23. DEAP-3600 Dark Matter Search

Author: 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., 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., Ward, M., and Kuźniak, M.
Published: 2016
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24. No difference in effectiveness between focused and radial shockwave therapy for treating patellar tendinopathy: a randomized controlled trial

Author: van der Worp, H., Zwerver, J., Hamstra, M., van den Akker-Scheek, I., and Diercks, R. L.
Published: 2014
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25. Transfer of information on palliative home care during the out-of-hours period

Author: De Bock, G H, Van Kampen, I M, Van der Goot, J H, Hamstra, M, Dekker, J H, Schuit, K W, and Van der Meer, K
Published: 2011
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26. 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

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

Author: Amaudruz, P.-A., primary, Batygov, M., additional, Beltran, B., additional, Bina, C.E., additional, Bishop, D., additional, Bonatt, J., additional, Boorman, G., additional, Boulay, M.G., additional, Broerman, B., additional, Bromwich, T., additional, Bueno, J.F., additional, Butcher, A., additional, Cai, B., additional, Chan, S., additional, Chen, M., additional, Chouinard, R., additional, Churchwell, S., additional, Cleveland, B.T., additional, Cranshaw, D., additional, Dering, K., additional, Dittmeier, S., additional, Duncan, F.A., additional, Dunford, M., additional, Erlandson, A., additional, Fatemighomi, N., additional, Ford, R.J., additional, Gagnon, R., additional, Giampa, P., additional, Golovko, V.V., additional, Gorel, P., additional, Gornea, R., additional, Grace, E., additional, Graham, K., additional, Grant, D.R., additional, Gulyev, E., additional, Hall, A., additional, Hallin, A.L., additional, Hamstra, M., additional, Harvey, P.J., additional, Hearns, C., additional, Jillings, C.J., additional, Kamaev, O., additional, Kemp, A., additional, Kuźniak, M., additional, Langrock, S., additional, La Zia, F., additional, Lehnert, B., additional, Li, O., additional, Lidgard, J.J., additional, Liimatainen, P., additional, Lim, C., additional, Lindner, T., additional, Linn, Y., additional, Liu, S., additional, Mathew, R., additional, McDonald, A.B., additional, McElroy, T., additional, McFarlane, K., additional, McLaughlin, J., additional, Mead, S., additional, Mehdiyev, R., additional, Mielnichuk, C., additional, Monroe, J., additional, Muir, A., additional, Nadeau, P., additional, Nantais, C., additional, Ng, C., additional, Noble, A.J., additional, O’Dwyer, E., additional, Ohlmann, C., additional, Olchanski, K., additional, Olsen, K.S., additional, Ouellet, C., additional, Pasuthip, P., additional, Peeters, S.J.M., additional, Pollmann, T.R., additional, Rand, E.T., additional, Rau, W., additional, Rethmeier, C., additional, Retière, F., additional, Seeburn, N., additional, Shaw, B., additional, Singhrao, K., additional, Skensved, P., additional, Smith, B., additional, Smith, N.J.T., additional, Sonley, T., additional, Stainforth, R., additional, Stone, C., additional, Strickland, V., additional, Sur, B., additional, Tang, J., additional, Taylor, J., additional, Veloce, L., additional, Vázquez-Jáuregui, E., additional, Walding, J., additional, Ward, M., additional, Westerdale, S., additional, White, R., additional, Woolsey, E., additional, and Zielinski, J., additional
Published: 2019
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28. DEAP-3600 Dark Matter Search

Author: Kuźniak, M., primary, Amaudruz, P.-A., additional, Batygov, M., additional, Beltran, B., additional, Bonatt, J., additional, Boulay, M.G., additional, Broerman, B., additional, Bueno, J.F., additional, Butcher, A., additional, Cai, B., additional, Chen, M., additional, Chouinard, R., additional, Cleveland, B.T., additional, Dering, K., additional, DiGioseffo, J., additional, Duncan, F., additional, Flower, T., additional, Ford, R., additional, Giampa, P., additional, Gorel, P., additional, Graham, K., additional, Grant, D.R., additional, Guliyev, E., additional, Hallin, A.L., additional, Hamstra, M., additional, Harvey, P., additional, Jillings, C.J., additional, Lawson, I., additional, Li, O., additional, Liimatainen, P., additional, Majewski, P., additional, McDonald, A.B., additional, McElroy, T., additional, McFarlane, K., additional, Monroe, J., additional, Muir, A., additional, Nantais, C., additional, Ng, C., additional, Noble, A.J., additional, Ouellet, C., additional, Palladino, K., additional, Pasuthip, P., additional, Peeters, S.J.M., additional, Pollmann, T., additional, Rau, W., additional, Retière, F., additional, Seeburn, N., additional, Singhrao, K., additional, Skensved, P., additional, Smith, B., additional, Sonley, T., additional, Tang, J., additional, Vázquez-Jáuregui, E., additional, Veloce, L., additional, Walding, J., additional, and Ward, M., additional
Published: 2016
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29. No difference in effectiveness between focused and radial shockwave therapy for treating patellar tendinopathy: a randomized controlled trial

Author: van der Worp, H., primary, Zwerver, J., additional, Hamstra, M., additional, van den Akker-Scheek, I., additional, and Diercks, R. L., additional
Published: 2013
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30. Transfer of information on palliative home care during the out-of-hours period

Author: De Bock, G. H., primary, Van Kampen, I. M., additional, Van der Goot, J. H., additional, Hamstra, M., additional, Dekker, J. H., additional, Schuit, K. W., additional, and Van der Meer, K., additional
Published: 2010
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31. No difference in effectiveness between focused and radial shockwave therapy for treating patellar tendinopathy: a randomized controlled trial.

Author: Worp, H., Zwerver, J., Hamstra, M., Akker-Scheek, I., and Diercks, R.
Subjects: RANDOMIZED controlled trials, TENDINITIS treatment, EXTRACORPOREAL shock wave therapy, JUMPER'S knee, HEALTH outcome assessment, THERAPEUTICS
Abstract: Purpose: The aim of the study was to compare the effectiveness of focused shockwave therapy (FSWT) and radial shockwave therapy (RSWT) for treating patellar tendinopathy. Methods: Patients were randomized into two groups. One group received three sessions of FSWT, and the other group received three sessions of RSWT. Both groups also received an eccentric training programme. Follow-up measurements took place 1, 4, 7 and 14 weeks after the final shockwave treatment. The primary outcome measure was the Victorian Institute of Sport Assessment-Patella (VISA-P) questionnaire. Secondary outcome measures were pain during ADL, sports activities and the decline squat. Results: Forty-three subjects (57 tendons) were included in the study. Twenty-one subjects (31 tendons) received FSWT, and 22 subjects (26 tendons) received RSWT. Both groups improved significantly on the VISA-P score, but there were no differences in improvement between the FSWT group (15 points on the VISA-P) and the RSWT group (9.6 points, n.s.). This was also the case for the secondary outcome measures. Conclusion: There were no statistically significant differences in effectiveness between FSWT and RSWT. It is therefore not possible to recommend one treatment over the other on grounds of outcome. Both groups improved significantly, although it is questionable whether this difference is clinically relevant. Level of evidence: II. [ABSTRACT FROM AUTHOR]
Published: 2014
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32. Free Carrier Generation in Semiconductors Induced by Absorption of Sub-Band Gap Light. A Photoelectrochemical Study with Nanoporous GaP

Author: Vanmaekelbergh, D., primary, Hamstra, M. A., additional, and van Pieterson, L., additional
Published: 1998
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33. Greatly Enhanced Sub‐Bandgap Photocurrent in Porous GaP Photoanodes

Author: Marín, F. Iranzo, primary, Hamstra, M. A., additional, and Vanmaekelbergh, D., additional
Published: 1996
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34. Clinical evaluation of lymphocyte sub-populations and oxygen radical production in sarcoidosis and idiopathic pulmonary fibrosis

Author: Groen, H., primary, Hamstra, M., additional, Aalbers, R., additional, van der Mark, T.W., additional, Koëter, G.H., additional, and Postma, D.S., additional
Published: 1994
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35. Evaluation of interferometric ellipsometer systems with a time resolution of one microsecond and faster

Author: Hemmes, K., Hamstra, M. A., Koops, K. R., Wind, M. M., Schram, T., Laet, J. De, and Bender, H.
Published: 1998
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36. 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.

37. The luminescence of Pb^2^+ in alkaline earth sulfates

Author: Folkerts, H. F., Hamstra, M. A., and Blasse, G.
Published: 1995
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38. Synthesis, Structure and Luminescence of New Ca~3SnSi~2O~9

Author: Blasse, G., Hamstra, M. A., Ijdo, D. J. W., and Plaisier, J. R.
Published: 1995
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39. The Luminescence of Filled s-Shell Ions in Hexavalent Tellurium Compounds

Author: Hamstra, M. A., Folkerts, H. F., and Blasse, G.
Published: 1995
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40. The liquid-argon scintillation pulseshape in DEAP-3600

Author: N. J. T. Smith, V. Strickland, M. Batygov, B. Lehnert, J. B. McLaughlin, K. Dering, I. N. Machulin, P. Garcia Abia, T. Pollmann, J. F. Bueno, D. Goeldi, C. Ng, R. Santorelli, J. M. Corning, P. Skensved, D. Gallacher, Jocelyn Monroe, M. Waqar, E. A. Garcés, F. La Zia, M. Kuźniak, C. Rethmeier, Laurelle Maria Veloce, Miguel Cárdenas-Montes, G. Fiorillo, Stefano Cavuoti, T. Sánchez-Pastor, Mark Guy Boulay, P. Pasuthip, C. Hearns, F. Retiere, C. J. Jillings, C. Ouellet, C. Nantais, B. Smith, Bei Cai, E. Vázquez-Jáuregui, O. Kamaev, M. C. Piro, C. Stone, N. Levashko, A. Butcher, S. Westerdale, Darren Grant, P. Giampa, F. A. Duncan, B. Broerman, B. Beltran, N. Seeburn, O. Litvinov, P. Nadeau, A. Joy, X. Li, Monica Dunford, T. Sonley, S. Viel, A. L. Hallin, V. Pesudo, S. J. M. Peeters, N. Fatemighomi, R. Ford, P. Adhikari, E. Sanchez Garcia, Giuseppe Longo, J. Walding, P. Majewski, A. Kemp, G. Kaur, R. Ajaj, R. Mehdiyev, A. Ilyasov, S. Langrock, P. Gorel, B. T. Cleveland, Martin Ward, C. Mielnichuk, Bhaskar Sur, C. E. Bina, G. R. Araujo, P. J. Harvey, I. Kochanek, J. Lock, A. Zuñiga-Reyes, S. J. Daugherty, A. Erlandson, J. Willis, Luca Doria, S. Pal, S. Garg, E. T. Rand, V. V. Golovko, T. McGinn, T. McElroy, R. Stainforth, P. Di Stefano, A. Grobov, K. Graham, A. B. McDonald, Y. Chen, A. Flower, M. Stringer, A. J. Noble, G. Oliviéro, M. Hamstra, R. Gagnon, Adhikari, P., Ajaj, R., Araujo, G. R., Batygov, M., Beltran, B., Bina, C. E., Boulay, M. G., Broerman, B., Bueno, J. F., Butcher, A., Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S. J., Di Stefano, P., Dering, K., Doria, L., Duncan, F. A., Dunford, M., Erlandson, A., Fatemighomi, N., Fiorillo, G., Flower, A., Ford, R. J., Gagnon, R., Gallacher, D., Garcés, E. A., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Golovko, V. V., Gorel, P., Graham, K., Grant, D. R., Grobov, A., Hallin, A. L., Hamstra, M., Harvey, P. J., Hearns, C., Ilyasov, A., Joy, A., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Langrock, S., La Zia, F., Lehnert, B., Levashko, N., Li, X., Litvinov, O., Lock, J., Longo, G., Machulin, I., 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., Oliviéro, G., Ouellet, C., Pal, S., Pasuthip, P., Peeters, S. J. M., Pesudo, V., Piro, M. -C., Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Sanchez García, E., Sánchez-Pastor, T., Santorelli, R., Seeburn, N., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stone, C., Strickland, V., Stringer, M., Sur, B., Vázquez-Jáuregui, E., Veloce, L., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.
Subjects: Photomultiplier, Physics - Instrumentation and Detectors, Physics and Astronomy (miscellaneous), Physics::Instrumentation and Detectors, Dark matter, FOS: Physical sciences, lcsh:Astrophysics, Scintillator, Wavelength shifter, 01 natural sciences, Particle detector, DEAP, Optics, 0103 physical sciences, lcsh:QB460-466, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010306 general physics, Engineering (miscellaneous), Physics, Scintillation, 010308 nuclear & particles physics, business.industry, Instrumentation and Detectors (physics.ins-det), Scintillation counter, lcsh:QC770-798, business
Abstract: DEAP-3600 is a liquid-argon scintillation detector looking for dark matter. Scintillation events in the liquid argon (LAr) are registered by 255 photomultiplier tubes (PMTs), and pulseshape discrimination (PSD) is used to suppress electromagnetic background events. The excellent PSD performance of LAr makes it a viable target for dark matter searches, and the LAr scintillation pulseshape discussed here is the basis of PSD. The observed pulseshape is a combination of LAr scintillation physics with detector effects. We present a model for the pulseshape of electromagnetic background events in the energy region of interest for dark matter searches. The model is composed of (a) LAr scintillation physics, including the so-called intermediate component, (b) the time response of the TPB wavelength shifter, including delayed TPB emission at $${\mathcal {O}}$$O(ms) time-scales, and c) PMT response. TPB is the wavelength shifter of choice in most LAr detectors. We find that approximately 10% of the intensity of the wavelength-shifted light is in a long-lived state of TPB. This causes light from an event to spill into subsequent events to an extent not usually accounted for in the design and data analysis of LAr-based detectors.
Published: 2020

41. Constraints on dark matter-nucleon effective couplings in the presence of kinematically distinct halo substructures using the DEAP-3600 detector

Author: Miguel Cárdenas-Montes, G. Oliviéro, Luca Doria, M. G. Boulay, A. Kemp, G. Kaur, R. Stainforth, Stefano Cavuoti, Bei Cai, O. Litvinov, P. Gorel, M. C. Piro, Monica Dunford, O. Kamaev, F. Retiere, S. Viel, P. Skensved, Xiujiang Li, C. Rethmeier, S. S. Farahani, I. Kochanek, J. Lock, A. Zuñiga-Reyes, C. Jillings, T. Hugues, N. J. T. Smith, D. Gallacher, C. E. Bina, C. Mielnichuk, M. Cadeddu, S. Westerdale, Bhaskar Sur, S. Langrock, J. B. McLaughlin, M. Hamstra, T. Pollmann, P. DelGobbo, S. Garg, M. Kuźniak, V. Pesudo, T. Sonley, B. Jigmeddorj, Jocelyn Monroe, David A. Sinclair, Leszek Roszkowski, A. C. Vincent, S. J. M. Peeters, G. Fiorillo, W. Bonivento, J. Walding, R. Santorelli, J. M. Corning, P. Giampa, T. Sánchez-Pastor, B. C. Smith, A. Ilyasov, D. J. Auty, I. N. Machulin, M. Lai, M. Stringer, A. B. McDonald, N. Fatemighomi, R. Ajaj, P. Adhikari, E. Sanchez Garcia, A. Erlandson, Martin Ward, Giuseppe Longo, E. T. Rand, E. Vázquez-Jáuregui, P. Garcia Abia, S. Pal, A. Joy, J. Willis, B. Lehnert, N. Levashko, A. L. Hallin, B. T. Cleveland, M. Waqar, E. A. Garcés, A. Grobov, K. Graham, I. Rodríguez-García, S. J. Daugherty, Y. Chen, D. Goeldi, T. McElroy, P. Di Stefano, Adhikari, P., Ajaj, R., Auty, D. J., Bina, C. E., Bonivento, W., Boulay, M. G., Cadeddu, M., Cai, B., Cardenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S., Delgobbo, P., Di Stefano, P., Doria, L., Dunford, M., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Gallacher, D., Garces, E. A., Abia, P. Garcia, 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, Kuzniak, M., Lai, M., Langrock, S., Lehnert, B., Levashko, N., Li, X., Litvinov, O., Lock, J., Longo, G., Machulin, I, Mcdonald, A. B., Mcelroy, T., Mclaughlin, J. B., Mielnichuk, C., Monroe, J., Oliviero, G., Pal, S., Peeters, S. J. M., Pesudo, V, Piro, M-C, Pollmann, T. R., Rand, E. T., Rethmeier, C., Retiere, F., Rodriguez-Garcia, I, Roszkowski, L., Sanchez Garcia, E., Sanchez-Pastor, T., Santorelli, R., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Stringer, M., Sur, B., Vazquez-Jauregui, E., Viel, S., Vincent, A. C., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuniga-Reyes, A.
Subjects: Physics, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Isovector, 010308 nuclear & particles physics, Isoscalar, Dark matter, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, High Energy Physics - Experiment, Dark matter halo, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Weakly interacting massive particles, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Effective field theory, Halo, 010306 general physics, Magnetic dipole, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: DEAP-3600 is a single-phase liquid argon detector aiming to directly detect Weakly Interacting Massive Particles (WIMPs), located at SNOLAB (Sudbury, Canada). After analyzing data taken during the first year of operation, a null result was used to place an upper bound on the WIMP-nucleon spin-independent, isoscalar cross section. This study reinterprets this result within a Non-Relativistic Effective Field Theory framework, and further examines how various possible substructures in the local dark matter halo may affect these constraints. Such substructures are hinted at by kinematic structures in the local stellar distribution observed by the Gaia satellite and other recent astronomical surveys. These include the Gaia Sausage (or Enceladus), as well as a number of distinct streams identified in recent studies. Limits are presented for the coupling strength of the effective contact interaction operators $\mathcal{O}_1$, $\mathcal{O}_3$, $\mathcal{O}_5$, $\mathcal{O}_8$, and $\mathcal{O}_{11}$, considering isoscalar, isovector, and xenonphobic scenarios, as well as the specific operators corresponding to millicharge, magnetic dipole, electric dipole, and anapole interactions. The effects of halo substructures on each of these operators are explored as well, showing that the $\mathcal{O}_5$ and $\mathcal{O}_8$ operators are particularly sensitive to the velocity distribution, even at dark matter masses above 100 GeV/$c^2$.
Published: 2020

42. 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

43. Enhanced External Counterpulsation for the Treatment of Angina With Nonobstructive Coronary Artery Disease.

Author: Ashokprabhu ND, Fox J, Henry TD, Schmidt CW, Tierney D, Gallatin J, Alvarez YR, Thompson L, Hamstra M, Shah SA, and Quesada O
Subjects: Humans, Female, Middle Aged, Male, Treatment Outcome, Canada, Angina Pectoris, Coronary Artery Disease complications, Coronary Artery Disease therapy, Counterpulsation
Abstract: Angina and nonobstructive coronary artery disease (ANOCA) is associated with poor outcomes and limited treatment options. Enhanced external counterpulsation (EECP) is a noninvasive treatment that involves applying external inflatable cuffs to the lower extremities to increase blood flow during diastole, followed by deflation during systole. Although EECP is approved for treatment in patients with refractory angina due to obstructive coronary artery disease, its effectiveness in treating patients with ANOCA with refractory angina is limited to small studies. We assessed the efficacy of EECP treatment in patients with ANOCA (defined as ≤50% stenosis in any major epicardial vessels) with refractory anginaby measuring changes in Canadian Cardiovascular Society (CCS) angina class, 6-minute walk test, Duke Activity Status Index (DASI), Seattle Angina Questionnaire 7 (SAQ7), and weekly anginal episodes pre-EECP and post-EECP treatment. A total of 101 patients with ANOCA with CCS class III/IV angina completed a full course of EECP treatment at 2 large EECP centers. In 101 patients with ANOCA the mean age (SD) of 60.6 (11.3) years and 62.4% of the cohort were women. We found significant improvements post-EECP treatment in CCS angina class (mean (SD) 3.4 (0.5) to 2.4 (2.9), p <0.001), 6-minute walk test (median 1200 (IQR 972 to 1411) to 1358 (1170 to 1600), p <0.001), DASI (mean (SD) 15.2 (11.6) to 31.5 (16.3), p <0.001), SAQ7 (mean (DS) 36.2 (24.7) to 31.5 (16.3), p <0.001), and weekly anginal episodes (mean (SD) 5.3 (3.5) to 2.4 (2.9), p <0.001). After EECP treatment, 71 patients (70.3%) had an improvement of ≥1 CCS angina class, including 33 (32.7%) patients improving by ≥2 CCS classes. In conclusion, in patients with ANOCA, EECP therapy reduces CCS angina class and improves exercise tolerance and capacity; and should be considered a part of optimal medical therapy., Competing Interests: Declaration of Competing Interest Dr. Quesada reports financial support from the National Institutes of Health. The remaining authors have no competing interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)
Published: 2024
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44. Prevalence and associated factors of post-traumatic stress disorder in parents whose infants have single ventricle heart disease.

Author: Bainton J, Trachtenberg F, McCrindle BW, Wang K, Boruta R, Brosig CL, Egerson D, Sood E, Calderon J, Doman T, Golub K, Graham A, Haas K, Hamstra M, Lindauer B, Sylvester D, Woodard F, Young-Borkowski L, and Mussatto KA
Subjects: Child, Female, Infant, Humans, Prevalence, Cohort Studies, Parents psychology, Stress, Psychological psychology, Stress Disorders, Post-Traumatic epidemiology, Stress Disorders, Post-Traumatic etiology, Heart Diseases complications
Abstract: Introduction: Post-traumatic stress disorder occurs in parents of infants with CHD, contributing to psychological distress with detrimental effects on family functioning and well-being. We sought to determine the prevalence and factors associated with post-traumatic stress disorder symptoms in parents whose infants underwent staged palliation for single ventricle heart disease., Materials and Methods: A large longitudinal multi-centre cohort study evaluated 215 mothers and fathers for symptoms of post-traumatic stress disorder at three timepoints, including post-Norwood, post-Stage II, and a final study timepoint when the child reached approximately 16 months of age, using the self-report questionnaire Impact of Event Scale - Revised., Results: The prevalence of probable post-traumatic stress disorder post-Norwood surgery was 50% of mothers and 39% of fathers, decreasing to 27% of mothers and 24% of fathers by final follow-up. Intrusive symptoms such as flashbacks and nightmares and hyperarousal symptoms such as poor concentration, irritability, and sudden physical symptoms of racing heart and difficulty breathing were particularly elevated in parents. Higher levels of anxiety, reduced coping, and decreased satisfaction with parenting were significantly associated with symptoms of post-traumatic stress disorder in parents. Demographic and clinical variables such as parent education, pre-natal diagnosis, medical complications, and length of hospital stay(s) were not significantly associated with symptoms of post-traumatic stress disorder., Discussion: Parents whose infants underwent staged palliation for single ventricle heart disease often reported symptoms of post-traumatic stress disorder. Symptoms persisted over time and routine screening might help identify parents at-risk and prompt referral to appropriate supports.
Published: 2023
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45. The Relationship of Family Factors to Psychosocial Outcomes in Children with Hypoplastic Left Heart Syndrome at 6 Years of Age.

Author: Mussatto KA, Trachtenberg FL, Wang K, Uzark K, Sood E, Lambert L, Hamstra M, Clarke S, Morrison T, Otto M, Picart A, Rathge K, Walter P, Woodard F, and Pemberton VL
Subjects: Female, Child, Humans, Quality of Life, Cross-Sectional Studies, Parents psychology, Mothers psychology, Hypoplastic Left Heart Syndrome surgery
Abstract: Objective: The objective of this study was to describe the relationships between family factors and outcomes for children with hypoplastic left heart syndrome (HLHS)., Study Design: This cross-sectional study was ancillary to the Pediatric Heart Network Single Ventricle Reconstruction Extension Study to examine family factors including parental mental health, quality of life (QOL), family resources, function and management, and their relationships to child psychosocial outcomes (adaptive behavior, internalizing and externalizing behaviors and health-related quality of life [HRQOL]) at 6 years of age., Results: Participants were parents (115 mothers, 71 fathers) of children with HLHS. Parents reported anxiety, QOL and family resources that were worse than the general population; 33% reported family dysfunction. There were no meaningful differences between reports from mothers and fathers. Parental perception of better child health was associated with better family management of the condition (P < .05). Several family management factors explained a moderate amount of variance in adaptive behavior (ΔR 2 = 0.08-0.14), adaptive skills (ΔR 2 = 0.19-0.21), and HRQOL scores (ΔR 2 = 0.04-0.18); little variance was explained in internalizing problems (ΔR 2 = 0.02-0.03) (all P < .05) above and beyond demographic and clinical variables., Conclusions: HLHS has a significant impact on both children and families. Relationships between child and family characteristics may impose risk or protection. Improved understanding of these associations should guide counseling and tailored interventions., (Copyright © 2022 Elsevier Inc. All rights reserved.)
Published: 2023
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46. First Direct Detection Constraints on Planck-Scale Mass Dark Matter with Multiple-Scatter Signatures Using the DEAP-3600 Detector.

Author: Adhikari P, Ajaj R, Alpízar-Venegas M, Auty DJ, Benmansour H, Bina CE, Bonivento W, Boulay MG, Cadeddu M, Cai B, Cárdenas-Montes M, Cavuoti S, Chen Y, Cleveland BT, Corning JM, Daugherty S, DelGobbo P, Di Stefano P, Doria L, Dunford M, Ellingwood E, Erlandson A, Farahani SS, Fatemighomi N, Fiorillo G, Gallacher D, García Abia P, Garg S, Giampa P, Goeldi D, Gorel P, Graham K, Grobov A, Hallin AL, Hamstra M, Hugues T, Ilyasov A, Joy A, Jigmeddorj B, Jillings CJ, 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 AB, McElroy T, McLaughlin JB, Mielnichuk C, Mirasola L, Monroe J, Oliviéro G, Pal S, Peeters SJM, Perry M, Pesudo V, Picciau E, Piro MC, Pollmann TR, Raj N, Rand ET, Rethmeier C, Retière F, Rodríguez-García I, Roszkowski L, Ruhland JB, Sanchez García E, Sánchez-Pastor T, Santorelli R, Seth S, Sinclair D, Skensved P, Smith B, Smith NJT, Sonley T, Stainforth R, Stringer M, Sur B, Vázquez-Jáuregui E, Viel S, Walding J, Waqar M, Ward M, Westerdale S, Willis J, and Zuñiga-Reyes A
Abstract: Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19} GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18} cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.
Published: 2022
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47. First Results from the DEAP-3600 Dark Matter Search with Argon at SNOLAB.

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, 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, Gulyev E, Hakobyan R, 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, Lidgard JJ, Lim C, Lindner T, Linn Y, Liu S, Majewski P, Mathew R, McDonald AB, McElroy T, 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, Tang J, Taylor J, Veloce L, Vázquez-Jáuregui E, Walding J, Ward M, Westerdale S, Woolsey E, and Zielinski J
Abstract: This Letter reports the first results of a direct dark matter search with the DEAP-3600 single-phase liquid argon (LAr) detector. The experiment was performed 2 km underground at SNOLAB (Sudbury, Canada) utilizing a large target mass, with the LAr target contained in a spherical acrylic vessel of 3600 kg capacity. The LAr is viewed by an array of PMTs, which would register scintillation light produced by rare nuclear recoil signals induced by dark matter particle scattering. An analysis of 4.44 live days (fiducial exposure of 9.87 ton day) of data taken during the initial filling phase demonstrates the best electronic recoil rejection using pulse-shape discrimination in argon, with leakage <1.2×10^{-7} (90% C.L.) between 15 and 31 keV_{ee}. No candidate signal events are observed, which results in the leading limit on weakly interacting massive particle (WIMP)-nucleon spin-independent cross section on argon, <1.2×10^{-44} cm^{2} for a 100 GeV/c^{2} WIMP mass (90% C.L.).
Published: 2018
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