G. D. Orebi Gann
A5072343424- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Particle Detector Development and Performance
- Atmospheric Ozone and Climate
- Quantum, superfluid, helium dynamics
- Scientific Research and Discoveries
- Radioactive contamination and transfer
- Nuclear physics research studies
- Spectroscopy and Laser Applications
- Nuclear Physics and Applications
- Earth Systems and Cosmic Evolution
- Analytical Chemistry and Chromatography
- Random lasers and scattering media
- Astronomy and Astrophysical Research
- Electron Spin Resonance Studies
- Atmospheric chemistry and aerosols
- Molecular Spectroscopy and Structure
- Thermal Radiation and Cooling Technologies
- Chemical Thermodynamics and Molecular Structure
- Quantum and Classical Electrodynamics
- Radiation Therapy and Dosimetry
University of California, Berkeley
2016-2025
Lawrence Berkeley National Laboratory
2016-2025
Campbell Collaboration
2023
University of Pennsylvania
2010-2021
University of California System
2020
Berkeley College
2020
United States Agency for International Development
2019
Cambridge Information Group
2015
Philadelphia University
2011-2014
University of Oxford
2006-2014
We report results from a combined analysis of solar neutrino data all phases the Sudbury Neutrino Observatory (SNO). By exploiting particle identification information obtained proportional counters installed during third phase, this improved background rejection in that phase experiment. The SNO resulted total flux active flavors ${}^{8}\mathrm{B}$ decays Sun...
Results are reported from a joint analysis of Phase I and II data the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is ${T}_{\mathrm{eff}}=3.5$ MeV, lowest yet achieved with water Cherenkov detector data. In units ${10}^{6}$ cm${}^{\ensuremath{-}2}$ ${\mathrm{s}}^{\ensuremath{-}1}$, total flux active-flavor neutrinos $^{8}\mathrm{B}$ decay in Sun measured using neutral current (NC) reaction on deuterons, no constraint neutrino spectrum, found to be...
Abstract New developments in liquid scintillators, high-efficiency, fast photon detectors, and chromatic sorting have opened up the possibility for building a large-scale detector that can discriminate between Cherenkov scintillation signals. Such could reconstruct particle direction species using light while also having excellent energy resolution low threshold of scintillator detector. Situated deep underground, utilizing new techniques computing reconstruction, this achieve unprecedented...
In this article we review the current state of field solar neutrinos, including flavour oscillations, non-standard effects, models, cross section measurements, and broad experimental program thus motivated enabled. We discuss historical discoveries that contributed to knowledge, define critical open questions be addressed in next decade. art standard uncertainties problems related composition, model neutrino fluxes, future prospects. nuclear reaction data relevant for fusion proton-proton...
Neutron-antineutron oscillations in nature would violate baryon number and indicate a potential underlying mechanism for the observed matter-antimatter asymmetry. Sudbury Neutrino Observatory reports limits on neutron-antineutron first time deuteron. These establish important constraints beyond-the-Standard-Model scenarios that involve baryon-number violation.
A key enabling technology for many liquid noble gas (LNG) detectors is the use of common wavelength shifting medium tetraphenyl butadiene (TPB). TPB thin films are used to shift ultraviolet scintillation light into visible spectrum detection and event reconstruction. Understanding efficiency optical properties these critical aspects in detector performance modeling hence ultimate physics sensitivity such experiments. This article presents first measurements room-temperature microphysical...
EOS is a technology demonstrator, designed to explore the capabilities of hybrid event detection technology, leveraging both Cherenkov and scintillation light simultaneously. With fiducial mass four tons, operate in high-precision regime, with sufficient size utilize time-of-flight information for full reconstruction, flexibility demonstrate range cutting edge technologies, simplicity design facilitate potential future deployment at alternative sites. Results from can inform neutrino...
The direction of individual <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mmultiscripts><a:mrow><a:mi mathvariant="normal">B</a:mi></a:mrow><a:mprescripts/><a:none/><a:mrow><a:mn>8</a:mn></a:mrow></a:mmultiscripts></a:mrow></a:math> solar neutrinos has been reconstructed using the <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mrow><d:mi>SNO</d:mi><d:mo>+</d:mo></d:mrow></d:math> liquid scintillator detector. Prompt, directional...
Abstract The SNO $$+$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>+</mml:mo> </mml:math> collaboration reports its first spectral analysis of long-baseline reactor antineutrino oscillation using 114 tonne-years data. Fitting the neutrino probability to observed energy spectrum yields constraints on mass-squared difference $$\Delta m^2_{21}$$ <mml:mrow> <mml:mi>Δ</mml:mi> <mml:msubsup> <mml:mi>m</mml:mi> <mml:mn>21</mml:mn> <mml:mn>2</mml:mn> </mml:msubsup> </mml:mrow>...
The long baseline between Earth and the Sun makes solar neutrinos an excellent test beam for exploring possible neutrino decay. signature of such decay would be energy-dependent distortion traditional survival probability which can fit using well-developed high-precision analysis methods. Here a model including is to all three phases 8B data taken by Sudbury Neutrino Observatory (SNO). This constrains lifetime mass state ν2 >8.08×10−5 s/eV at 90% confidence. An combining this SNO result with...
Abstract This paper presents measurements of the scintillation light yield and time profile for a number concentrations water-based liquid scintillator, formulated from linear alkylbenzene (LAB) 2,5-diphenyloxazole (PPO). We find that is with concentration scintillator in water between 1 10% slope $$127.9\pm 17.0$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>127.9</mml:mn> <mml:mo>±</mml:mo> <mml:mn>17.0</mml:mn> </mml:mrow> </mml:math> ph/MeV/concentration...
A measurement of the $^{8}\mathrm{B}$ solar neutrino flux has been made using a 69.2 kt-day dataset acquired with $\mathrm{SNO}+$ detector during its water commissioning phase. At energies above 6 MeV is an extremely pure sample elastic scattering events, owing primarily to detector's deep location, allowing accurate relatively little exposure. In that energy region best fit background rate $0.2{5}_{\ensuremath{-}0.07}^{+0.09}\text{ }\text{...
This paper presents studies of the performance water-based liquid scintillators (WbLS) in both 1-kt and 50-kt detectors. Performance is evaluated comparison to pure water Cherenkov detectors a nominal model for scintillator metrics include energy, vertex, angular resolution, along with metric ability separate from scintillation signal as being representative various particle identification capabilities that depend on Cherenkov/scintillation ratio. We also modify time profile light study same...
The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. nearest nuclear reactors are located 240 km away Ontario, Canada. This analysis uses events with energies lower than any previous large water Two analytical methods used to distinguish from background 190 days data and yield consistent for combined significance 3.5σ.
A search has been made for neutrinos from the hep reaction in Sun and diffuse supernova neutrino background (DSNB) using data collected during first operational phase of Sudbury Neutrino Observatory, with an exposure 0.65 kilotonne-years. For search, two events are observed effective electron energy range 14.3 MeV <T_eff< 20 where 3.1 expected. After accounting oscillations, upper limit 2.3x10^4 cm^-2s^-1 at 90% confidence level is inferred on integral total flux neutrinos. DSNB neutrinos,...
A search has been made for sinusoidal periodic variations in the $^8$B solar neutrino flux using data collected by Sudbury Neutrino Observatory over a 4-year time interval. The variation at period of one year is consistent with modulation Earth's orbital eccentricity. No significant periodicities are found periods between 1 day and 10 years either an unbinned maximum likelihood analysis or Lomb-Scargle periodogram analysis. inconsistent hypothesis that results recent Sturrock et al., based...
Results are reported on the measurement of atmospheric neutrino-induced muon flux at a depth 2 kilometers below Earth's surface from 1229 days operation Sudbury Neutrino Observatory (SNO). By measuring through-going muons as function zenith angle, SNO experiment can distinguish between oscillated and unoscillated portion neutrino flux. A total 514 muonlike events measured $\ensuremath{-}1\ensuremath{\le}\mathrm{cos}{\ensuremath{\theta}}_{\mathrm{zenith}}\ensuremath{\le}0.4$ in exposure...
The ability to separately identify the Cherenkov and scintillation light components produced in scintillating mediums holds potential for a major breakthrough neutrino detection technology, allowing development of large, low-threshold, directional detector with broad physics program. CHESS (CHErenkov / Scintillation Separation) experiment employs an innovative design array small, fast photomultiplier tubes state-of-the-art electronics demonstrate reconstruction ring medium based on photon...
The R&D mission of the Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is described in detail. ANNIE is: (1) an important measurement neutrino-nucleus interactions focusing specifically on neutron production, and (2) effort focused using new photodetector technology chemical additives to make advanced water-base neutrino detectors. experiment consists a small Water Cherenkov detector, instrumented with both conventional photomultiplier tubes (PMTs) Large Area Picosecond...
Abstract The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a 26-ton water Cherenkov neutrino detector installed on the Booster Beam (BNB) at Fermilab. Its main physics goals are to perform measurement of neutron yield from neutrino-nucleus interactions, as well charged-current cross section muon neutrinos. An equally important focus research and development new technologies target media. Specifically, water-based liquid scintillator (WbLS) interest novel medium, it allows...
Abstract This manuscript describes measurements of water-based liquid scintillators (WbLS), demonstrating separation the Cherenkov and scintillation components using a low energy $$\beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>β</mml:mi> </mml:math> source fast timing response Large Area Picosecond Photodetector (LAPPD). Additionally, time profiles three WbLS mixtures, defined by relative fractions scintillating compound, are characterized, with improved...
This white paper is a condensation of report by committee appointed jointly the Nuclear Science and Physics Divisions at Lawrence Berkeley National Laboratory (LBNL). The goal this study was to identify most promising technique(s) for resolving neutrino mass hierarchy. For part, we have relied on calculations simulations presented proponents various experiments. We included evaluations opportunities challenges these experiments based what available already in literature.
Abstract One of the most promising approaches for next generation neutrino experiments is realization large hybrid Cherenkov/scintillation detectors made possible by recent innovations in photodetection technology and liquid scintillator chemistry. The development a potentially suitable future detector with particularly slow light emission discussed present publication. This cocktail compared respect to its fundamental characteristics (scintillation efficiency, transparency, time profile...
A first measurement of neutrinos from the CNO fusion cycle in Sun would allow a resolution to current solar metallicity problem. Detection these low-energy requires low-threshold detector, while discrimination radioactive backgrounds region interest is significantly enhanced via directional sensitivity. This combination can be achieved water-based liquid scintillator target, which offers energy beyond standard water Cherenkov detector. We study sensitivity such detector under various and...