D. Gallacher
A5000657853- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Neutrino Physics Research
- Cosmology and Gravitation Theories
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Radiation Therapy and Dosimetry
- Medical Imaging Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Radioactive Decay and Measurement Techniques
- Metallic Glasses and Amorphous Alloys
- Radioactive contamination and transfer
- Radioactivity and Radon Measurements
- Magnetic Properties and Applications
- Quantum, superfluid, helium dynamics
- Radiation Effects in Electronics
- Spectroscopy and Laser Applications
- Magnetic Properties and Synthesis of Ferrites
- CCD and CMOS Imaging Sensors
McGill University
2022-2025
Carleton University
2019-2023
Laurentian University
2023
Snolab
2023
City of Glasgow College
1984
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 LAr contained in spherical acrylic vessel. This paper reports on the analysis $758\text{ }\text{ }\mathrm{tonne}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{day}$ exposure taken over period 231 live-days during first year operation. No candidate signal events are observed WIMP-search region interest, which...
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 was performed a blind analysis of data collected over 813 d live time DEAP-3600, 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate were observed, leading to the first direct detection constraints on matter. Leading limits constrain masses between 8.3×10^{6} 1.2×10^{19}...
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, null result was used place an upper bound on WIMP-nucleon, spin-independent, isoscalar cross section. This study reinterprets this within nonrelativistic effective field theory framework and further examines how various possible substructures in local dark matter halo may...
The DEAP-3600 experiment is searching for weakly interacting massive particles dark matter with a $\text{ }3.3\text{ }\ifmmode\times\else\texttimes\fi{}1{0}^{3}\text{kg}$ single phase liquid argon (LAr) target, located 2.1 km underground at SNOLAB. experimental signature of interactions kilo electron volt--scale $^{40}\mathrm{Ar}$ nuclear recoils producing 128 nm LAr scintillation photons observed by photomultiplier tubes. largest backgrounds in are electronic (ERs) induced...
Abstract The specific activity of the $$\beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>β</mml:mi> </mml:math> decay $$^{39}$$ <mml:msup> <mml:mrow /> <mml:mn>39</mml:mn> </mml:msup> Ar in atmospheric argon is measured using DEAP-3600 detector. DEAP-3600, located 2 km underground at SNOLAB, uses a total (3269 ± 24) kg liquid distilled from atmosphere to search for dark matter. This detector well-suited measure owing its very low background levels. achieved two...
Liquid xenon time projection chambers are promising detectors to search for neutrinoless double beta decay (0$\nu \beta \beta$), due their response uniformity, monolithic sensitive volume, scalability large target masses, and suitability extremely low background operations. The nEXO collaboration has designed a tonne-scale chamber that aims 0$\nu \beta$ of \ce{^{136}Xe} with projected half-life sensitivity $1.35\times 10^{28}$~yr. To reach this sensitivity, the design goal is $\leq$1\%...
Neutrinoless double beta decay is one of the most sensitive probes for new physics beyond Standard Model particle physics. One isotopes under investigation <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mmultiscripts><a:mi>Xe</a:mi><a:mprescripts/><a:none/><a:mn>136</a:mn></a:mmultiscripts></a:math>, which would into <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mmultiscripts><b:mi>Ba</b:mi><b:mprescripts/><b:none/><b:mn>136</b:mn></b:mmultiscripts></b:math>. Detecting...
The specific activity of the beta decay $^{39}$Ar in atmospheric argon is measured using DEAP-3600 detector. DEAP-3600, located 2 km underground at SNOLAB, uses a total (3269 $\pm$ 24) kg liquid distilled from atmosphere to search for dark matter. This detector with very low background pulseshape discrimination differentiate between nuclear recoils and electron well-suited measure $^{39}$Ar. With 167 live-days data, time extraction [0.964 0.001 (stat) 0.024 (sys)] Bq/kg$_{\rm atmAr}$ which...
Electron-neutrino charged-current interactions with xenon nuclei were modeled in the nEXO neutrinoless double-<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>β</a:mi></a:math> decay detector (<c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mo>∼</c:mo><c:mn>5</c:mn></c:math> metric ton, 90% <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"...
Future large liquid argon direct dark matter detectors can benefit greatly from an efficient surface background rejection technique. To aid the development of these scale a test stand, Argon-1, has been constructed at Carleton University, Ottawa, Canada, in noble detector lab. It aims to novel technique using thin layer slow scintillating material vessel. Through pulse-shape discrimination light layer, events be discriminated events. The will implemented with high-granularity SiPMs for...
Abstract In liquid argon-based particle detectors, slow wavelength shifters (WLSs) could be used alongside the common, nanosecond scale, WLS tetraphenyl butadiene (TPB) for background mitigation purposes. At room temperature, pyrene has a moderate fluorescence light yield (LY) and time constant of order hundreds nanoseconds. this work, four pyrene-doped polystyrene films with various purities concentrations were characterized in terms LY decay constants range temperature between 4 K 300...
The Light only Liquid Xenon (LoLX) experiment is a prototype detector aimed to study liquid xenon (LXe) light properties and various photodetection technologies. LoLX also quantify LXe's time resolution as potential scintillator for 10~ps time-of-flight (TOF) PET. Another key goal of perform time-based separation Cerenkov scintillation photons new background rejection methods in LXe experiments. To achieve this separation, set be equipped with photon-to-digital converters (PDCs), photosensor...