J. L. Orrell
A5054610758- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Historical Art and Culture Studies
- Nuclear Physics and Applications
- Radioactivity and Radon Measurements
- Radioactive contamination and transfer
- Shakespeare, Adaptation, and Literary Criticism
- Cosmology and Gravitation Theories
- Radioactive Decay and Measurement Techniques
- Advanced Semiconductor Detectors and Materials
- Theatre and Performance Studies
- Muon and positron interactions and applications
- Quantum, superfluid, helium dynamics
- Superconducting and THz Device Technology
- Scottish History and National Identity
- Scientific Research and Discoveries
- Radiation Effects in Electronics
- CCD and CMOS Imaging Sensors
- Historical Influence and Diplomacy
- Renaissance and Early Modern Studies
Pacific Northwest National Laboratory
2015-2024
Battelle
2007-2021
National Technical Information Service
2010-2012
Office of Scientific and Technical Information
2009-2012
European Organization for Nuclear Research
2012
United States Department of Commerce
2010-2012
University of South Carolina
2011
University of California, Berkeley
2010
University of Washington
2001-2007
Seattle University
2001
We report on several features in the energy spectrum from an ultralow-noise germanium detector operated deep underground. By implementing a new technique able to reject surface events, number of cosmogenic peaks can be observed for first time. discuss irreducible excess bulklike events below 3 keV ionization energy. These could caused by unknown backgrounds, but also dark matter interactions consistent with DAMA/LIBRA. It is not yet possible determine their origin. Improved constraints are...
The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about energy dependence of nu(e) survival probability. measurements were made with dissolved NaCl in heavy water to enhance sensitivity and signature for neutral-current interactions. is found be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), agreement previous standard models. A global analysis these other reactor results yields Deltam(2)=7.1(+1.2)(-0.6)...
The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest all low-energy neutrino couplings. This mode interaction offers new opportunities to study properties and leads a miniaturization detector size, with potential technological applications. We observed this process at 6.7σ confidence level, using low-background, 14.6-kilogram CsI[Na] scintillator exposed emissions from Spallation Neutron...
Results are reported from the complete salt phase of Sudbury Neutrino Observatory experiment in which NaCl was dissolved D$_2$O target. The addition enhanced signal neutron capture, as compared to pure detector. By making a statistical separation charged-current events other types based on event-isotropy criteria, effective electron recoil energy spectrum has been extracted. In units $ 10^6$ cm$^{-2}$ s$^{-1}$, total flux active-flavor neutrinos $^8$B decay Sun is found be...
Fifteen months of cumulative CoGeNT data are examined for indications an annual modulation, a predicted signature weakly interacting massive particle (WIMP) interactions. Presently available support the presence modulated component unknown origin, with parameters prima facie compatible galactic halo composed light-mass WIMPs. Unoptimized estimators yield statistical significance modulation ∼2.8σ, limited by short exposure.
CoGeNT employs p-type point-contact (PPC) germanium detectors to search for Weakly Interacting Massive Particles (WIMPs). By virtue of its low energy threshold and ability reject surface backgrounds, this type device allows an emphasis on low-mass dark matter candidates (wimp mass about 10 GeV/c2). We report the characteristics PPC detector presently taking data at Soudan Underground Laboratory, elaborating aspects shielding, acquisition, instrumental stability, analysis, background...
SuperCDMS SNOLAB will be a next-generation experiment aimed at directly detecting low-mass (< 10 GeV/c$^2$) particles that may constitute dark matter by using cryogenic detectors of two types (HV and iZIP) target materials (germanium silicon). The is being designed with an initial sensitivity to nuclear recoil cross sections ~ 1 x 10$^{-43}$ cm$^2$ for particle mass GeV/c$^2$, capacity continue exploration both smaller masses better sensitivities. phonon the HV sufficient detect recoils from...
We present the first limits on inelastic electron-scattering dark matter and photon absorption using a prototype SuperCDMS detector having charge resolution of 0.1 electron-hole pairs (CDMS HVeV, 0.93 g CDMS high-voltage device). These electron-recoil significantly improve experimental constraints particles with masses as low 1 MeV/c^{2}. demonstrate sensitivity to photons competitive other leading approaches but substantially less exposure (0.49 d). results scientific potential...
The M ajorana D emonstrator will search for the neutrinoless double-beta<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mo stretchy="false">(</mml:mo><mml:mi>β</mml:mi><mml:mi>β</mml:mi><mml:mfenced separators="|"><mml:mrow><mml:mn fontstyle="italic">0</mml:mn><mml:mi>ν</mml:mi></mml:mrow></mml:mfenced><mml:mo stretchy="false">)</mml:mo></mml:math>decay of isotope<mml:math id="M2"/>Ge with a mixed array enriched and natural germanium detectors. observation this rare...
The SuperCDMS experiment is designed to directly detect weakly interacting massive particles (WIMPs) that may constitute the dark matter in our Galaxy. During its operation at Soudan Underground Laboratory, germanium detectors were run CDMSlite mode gather data sets with sensitivity specifically for WIMPs masses ${<}$10 GeV/$c^2$. In this mode, a higher detector-bias voltage applied amplify phonon signals produced by drifting charges. This paper presents studies of experimental noise and...
The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. Demonstrator comprises 44.1 kg (29.7 enriched ^{76}Ge) split between two modules contained a low background shield at the Sanford Underground Research Facility Lead, South Dakota. Here we present results from data taken during construction, commissioning, and start full operations. We achieve unprecedented energy resolution 2.5 keV FWHM Q_{ββ} very with no...
This article presents an analysis and the resulting limits on light dark matter inelastically scattering off of electrons, photon axion-like particle absorption, using a second-generation SuperCDMS high-voltage eV-resolution detector. The 0.93 gram Si detector achieved 3 eV phonon energy resolution; for bias 100 V, this corresponds to charge resolution 3% single electron-hole pair. spectrum is reported from blind with 1.2 gram-days exposure acquired in above-ground laboratory. With carrier...
We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with baseline energy resolution of ${\ensuremath{\sigma}}_{E}=3.86\ifmmode\pm\else\textpm\fi{}0.04(\mathrm{stat}{)}_{\ensuremath{-}0.00}^{+0.19}(\mathrm{syst})\text{ }\text{ }\mathrm{eV}$. This exclusion analysis sets the most stringent scattering cross-section achieved by cryogenic for matter particle masses from 93 to $140\text{ }\mathrm{MeV}/{c}^{2}$, raw exposure 9.9 d...
This article presents constraints on dark-matter-electron interactions obtained from the first underground data-taking campaign with multiple SuperCDMS HVeV detectors operated in same housing. An exposure of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>7.63</a:mn><a:mtext> </a:mtext><a:mtext> </a:mtext><a:mi mathvariant="normal">g</a:mi><a:mtext>−</a:mtext><a:mi>days</a:mi></a:mrow></a:math> is used to set upper limits scattering cross section for dark...
A claim for evidence of dark matter interactions in the DAMA experiment has been recently reinforced. We employ a new type germanium detector to conclusively rule out standard isothermal galactic halo weakly interacting massive particles as explanation annual modulation effect leading claim. Bounds are similarly imposed on suggestion that pseudoscalars might lead effect. describe sensitivity light achievable with our device, particular, next-to-minimal supersymmetric model candidates.
We report the result of a blinded search for Weakly Interacting Massive Particles (WIMPs) using majority SuperCDMS Soudan dataset. With an exposure 1690 kg days, single candidate event is observed, consistent with expected backgrounds. This analysis (combined previous Ge results) sets upper limit on spin-independent WIMP--nucleon cross section $1.4 \times 10^{-44}$ ($1.0 10^{-44}$) cm$^2$ at 46 GeV/$c^2$. These results set strongest limits WIMP--germanium-nucleus interactions masses $>$12
As part of the Snowmass process, Cosmic Frontier WIMP Direct Detection subgroup (CF1) has drawn on input from and broader Particle Physics community to produce this document. The charge CF1 was (a) summarize current status projected sensitivity direct detection experiments worldwide, (b) motivate dark matter searches over a broad parameter space by examining spectrum models, (c) establish consensus type experimental program required explore that space, (d) identify common infrastructure...
The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) searches for interactions between dark matter particles and germanium nuclei in cryogenic detectors. has achieved a energy with improved sensitivity to low-mass (<10 GeV/c$^2$) particles. We present an analysis of the final CDMSlite data set, taken different detector than was used two previous sets. This includes "salting" method protect against bias, noise discrimination, background modeling, use profile...
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...
Abstract The nEXO neutrinoless double beta (0 νββ ) decay experiment is designed to use a time projection chamber and 5000 kg of isotopically enriched liquid xenon search for the in 136 Xe. Progress detector design, paired with higher fidelity its simulation an advanced data analysis, based on one used final results EXO-200, produce sensitivity prediction that exceeds half-life 10 28 years. Specifically, improvements have been made understanding production scintillation photons charge as...
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...