A5101426477- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Quantum, superfluid, helium dynamics
- Nuclear physics research studies
- Vacuum and Plasma Arcs
- Advanced Sensor Technologies Research
- Particle accelerators and beam dynamics
- Solar and Space Plasma Dynamics
- Mass Spectrometry Techniques and Applications
- Welding Techniques and Residual Stresses
- Gamma-ray bursts and supernovae
- Photocathodes and Microchannel Plates
- Noncommutative and Quantum Gravity Theories
- Metal and Thin Film Mechanics
- CCD and CMOS Imaging Sensors
Drexel University
2014-2023
Tokyo University of Information Sciences
2023
The University of Tokyo
2023
TRIUMF
2019
University of British Columbia
2019
A search for neutrinoless double-beta decay ($0\nu\beta\beta$) in $^{136}$Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between $0\nu\beta\beta$ and background events. Relative previous analyses, signal detection efficiency has been raised from 80.8% 96.4$\pm$3.0% energy resolution of detector at Q-value improved $\sigma/E=1.23\%$ $1.15\pm0.02\%$ upgraded detector. Accounting new data, median 90% confidence level half-life sensitivity this analysis...
The next-generation Enriched Xenon Observatory (nEXO) is a proposed experiment to search for neutrinoless double beta ($0\nu\beta\beta$) decay in $^{136}$Xe with target half-life sensitivity of approximately $10^{28}$ years using $5\times10^3$ kg isotopically enriched liquid-xenon time projection chamber. This improvement two orders magnitude over current limits obtained by significant increase the mass, monolithic and homogeneous configuration active medium, multi-parameter measurements...
The projected performance and detector configuration of nEXO are described in this pre-Conceptual Design Report (pCDR). is a tonne-scale neutrinoless double beta ($0νββ$) decay search $^{136}$Xe, based on the ultra-low background liquid xenon technology validated by EXO-200. With $\simeq$ 5000 kg enriched to 90% isotope 136, has half-life sensitivity approximately $10^{28}$ years. This represents an improvement about two orders magnitude with respect current results. Based experience gained...
A search for Lorentz- and $CPT$-violating signals in the double beta decay spectrum of $^{136}\mathrm{Xe}$ has been performed using an exposure $100\text{ }\text{ }\mathrm{kg}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{yr}$ with EXO-200 detector. No significant evidence spectral modification due to isotropic Lorentz-violation was found, a two-sided limit $\ensuremath{-}2.65\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{...
We apply deep neural networks (DNN) to data from the EXO-200 experiment. In studied cases, DNN is able reconstruct relevant parameters—total energy and position—directly raw digitized waveforms, with minimal exceptions. For first time, developed algorithms are evaluated on real detector calibration data. The accuracy of reconstruction either reaches or exceeds what was achieved by conventional approaches over course Most existing event classification in particle physics trained Monte Carlo...
EXO-200 is a single phase liquid xenon detector designed to search for neutrinoless double-beta decay of $^{136}$Xe. Here we report on various Majoron-emitting modes based 100 kg$\cdot$yr exposure A lower limit $T^{^{136}Xe}_{1/2} >1.2 \cdot 10^{24}$ yr at 90% C.L. the half-life spectral index = 1 Majoron was obtained, corresponding constraint Majoron-neutrino coupling constant $|< g^{M}_{ee} >|<$ (0.8-1.7)$\cdot$10$^{-5}$.
Alpha decays in the EXO-200 detector are used to measure fraction of charged $^{218}\text{Po}$ and $^{214}\text{Bi}$ daughters created from $\ensuremath{\alpha}$ $\ensuremath{\beta}$ decays, respectively. $^{222}\text{Rn} \ensuremath{\alpha}$ liquid xenon (LXe) found produce $^{218}\text{Po}^{+}$ ions $50.3\ifmmode\pm\else\textpm\fi{}3.0%$ time, while remainder atoms neutral. The $^{214}\text{Bi}^{+}$ $^{214}\text{Pb} \ensuremath{\beta}$ LXe is be $76.4\ifmmode\pm\else\textpm\fi{}5.7%$,...
The EXO-200 Collaboration is searching for neutrinoless double $\ensuremath{\beta}$ decay using a liquid xenon (LXe) time projection chamber. This measurement relies on modeling the transport of charge deposits produced by interactions in LXe to allow discrimination between signal and background events. Here we present measurements transverse diffusion constant drift velocity electrons at fields 20 V/cm 615 data. At operating field 380 measures...
The search for neutrinoless double-beta decay (0νββ) requires extremely low background and a good understanding of their sources influence on the rate in region parameter space relevant to 0νββ signal. We report studies various β γ backgrounds liquid-xenon-based EXO-2000νββ experiment. With this work we try better understand location strength specific compare conclusions radioassay results taken before during detector construction. Finally, discuss implications these EXO-200 as well...
Progress on a method of barium tagging for the nEXO double beta decay experiment is reported. Absorption and emission spectra deposits atoms ions in solid xenon matrices are presented. Excitation prominent lines, temperature dependence, bleaching fluorescence reveal existence different matrix sites. A regular series sharp lines observed ${\mathrm{Ba}}^{+}$ identified with some type hydride molecule. Lower limits quantum efficiency principal Ba transition Under current conditions, an image...
Future tonne-scale liquefied noble gas detectors depend on efficient light detection in the VUV range. In past years Silicon Photomultipliers (SiPMs) have emerged as a valid alternative to standard photomultiplier tubes or large area avalanche photodiodes. The next generation double beta decay experiment, nEXO, with 5 tonne liquid xenon time projection chamber, will use SiPMs for detecting $178\,\text{nm}$ scintillation light, order achieve an energy resolution of $\sigma / Q_{\beta\beta} =...
Liquid xenon (LXe) is employed in a number of current and future detectors for rare event searches. We use the EXO-200 experimental data to measure absolute scintillation ionization yields generated by $\ensuremath{\gamma}$ interactions from $^{228}\mathrm{Th}$ (2615 keV), $^{226}\mathrm{Ra}$ (1764 $^{60}\mathrm{Co}$ (1332 keV 1173 keV) calibration sources, over range electric fields. The $W$ value that defines recombination-independent energy scale measured be...
As neutrinoless double-beta decay experiments become more sensitive and intrinsic radioactivity in detector materials is reduced, previously minor contributions to the background must be understood eliminated. With this mind, cosmogenic backgrounds have been studied with EXO-200 experiment. Using TPC, muon flux (through a flat horizontal surface) underground at Waste Isolation Pilot Plant (WIPP) has measured {\Phi} = 4.07 $\pm$ 0.14 (sys) 0.03 (stat) $\times$ $10^{-7}$cm$^{-2}$ s$^{-1}$,...
We present a search for electron-recoil signatures from the charged-current absorption of fermionic dark matter using EXO-200 detector. report an average background rate $6.8\ifmmode\times\else\texttimes\fi{}{10}^{4}\text{ }\text{ }\mathrm{cts}\text{ }{\mathrm{kg}}^{\ensuremath{-}1}\text{ }{\mathrm{yr}}^{\ensuremath{-}1}\text{ }{\mathrm{keV}}^{\ensuremath{-}1}$ above 4 MeV and find no statistically significant excess over our projection. Using total $^{136}\mathrm{Xe}$ exposure 234.1 kg yr,...
A search for Majoron-emitting modes of the neutrinoless double-beta decay $^{136}$Xe is performed with full EXO-200 dataset. This dataset consists a total exposure 234.1 kg$\cdot$yr, and includes data detector upgrades that have improved energy threshold relative to previous searches. lower limit T$_{1/2}^{\rm{^{136}Xe}}>$4.3$\cdot$10$^{24}$ yr at 90\% C.L. on half-life spectral index $n=1$ Majoron was obtained, factor 3.6 more stringent than from EXO-200, corresponding constraint...
We describe a system to transport and identify barium ions produced in liquid xenon, as part of R&D towards the second phase double beta decay experiment, nEXO. The goal is Ba ion resulting from an extremely rare nuclear isotope 136Xe, hence providing confirmation occurrence decay. This achieved through Resonance Ionization Spectroscopy (RIS). In test setup described here, can be xenon or vacuum collected on clean substrate. substrate then removed analysis chamber under vacuum, where...
Searches for double beta decay of $^{134}$Xe were performed with EXO-200, a single-phase liquid xenon detector designed to search neutrinoless $^{136}$Xe. Using an exposure $29.6\text{ kg}\!\cdot\!\text{yr}$, the lower limits $\text{T}_{1/2}^{2\nu\beta\!\beta}>8.7\cdot10^{20}\text{ yr}$ and $\text{T}_{1/2}^{0\nu\beta\!\beta}>1.1\cdot10^{23}\text{ at 90% confidence level derived, corresponding half-life sensitivities $1.2\cdot10^{21}\text{ $1.9\cdot10^{23}\text{ yr}$. These exceed those in...
EXO-200 is a single phase liquid xenon detector designed to search for neutrinoless double-beta decay of $^{136}$Xe the ground state $^{136}$Ba. We report here on two-neutrino first $0^+$ excited state, $0^+_1$, $^{136}$Ba based 100 kg$\cdot$yr exposure $^{136}$Xe. Using specialized analysis employing machine learning algorithm, we obtain 90% CL half-life sensitivity $1.7 \times 10^{24}$ yr. find no statistically significant evidence $2\nu\beta\beta$ resulting in lower limit $T^{2\nu}_{1/2}$...
The EXO-200 experiment searched for neutrinoless double-beta decay of $^{136}$Xe with a single-phase liquid xenon detector. It used an active mass 110 kg 80.6%-enriched in ultra-low background time projection chamber ionization and scintillation detection readout. This paper describes the design performance various support systems necessary detector operation, including cryogenics, handling, controls. Novel features system were driven by need to protect thin-walled containing xenon, achieve...
Generative Adversarial Networks trained on samples of simulated or actual events have been proposed as a way generating large datasets at reduced computational cost. In this work, novel approach to perform the simulation photodetector signals from time projection chamber EXO-200 experiment is demonstrated. The method based Wasserstein Network - deep learning technique allowing for implicit non-parametric estimation population distribution given set objects. Our network real calibration data...
nEXO is a proposed experiment to search for the neutrino-less double beta decay (0νββ) of 136Xe in tonne-scale liquid xenon time projection chamber (TPC) . The TPC will be equipped with charge collection tiles form anode. In this work, reconstruction performance anode design studied dedicated simulation package. A multi-variate method and deep neural network are developed distinguish simulated 0νββ signals from backgrounds arising trace levels natural radioactivity detector materials. These...