B. J. Land
A5043829027- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Quantum Information and Cryptography
- Quantum many-body systems
- Cancer, Stress, Anesthesia, and Immune Response
- Quantum and electron transport phenomena
- Receptor Mechanisms and Signaling
- Neuropeptides and Animal Physiology
- Nuclear physics research studies
- Airway Management and Intubation Techniques
- Particle accelerators and beam dynamics
- Astro and Planetary Science
- Superconducting Materials and Applications
- Radiology practices and education
- Quantum optics and atomic interactions
- Quantum Computing Algorithms and Architecture
- Advanced Chemical Sensor Technologies
- Nuclear Physics and Applications
- Synthesis and properties of polymers
University of Pennsylvania
2020-2024
California University of Pennsylvania
2024
University of California, Berkeley
2016-2023
Lawrence Berkeley National Laboratory
2016-2023
The Royal Melbourne Hospital
2020
Georgia Institute of Technology
2012-2016
SNO+ is a large liquid scintillator-based experiment located 2km underground at SNOLAB, Sudbury, Canada. It reuses the Sudbury Neutrino Observatory detector, consisting of 12m diameter acrylic vessel which will be filled with about 780 tonnes ultra-pure scintillator. Designed as multipurpose neutrino experiment, primary goal search for neutrinoless double-beta decay (0$\nu\beta\beta$) 130Te. In Phase I, detector loaded 0.3% natural tellurium, corresponding to nearly 800 kg 130Te, an expected...
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...
We demonstrate dynamic stabilization of a strongly interacting quantum spin system realized in spin-1 atomic Bose-Einstein condensate. The spinor condensate is initialized to an unstable fixed point the spin-nematic phase space, where subsequent free evolution gives rise squeezing and mixing. To stabilize system, periodic microwave pulses are applied that rotate many-body fluctuations limit their growth. stability diagram for range pulse periods shifts dynamics measured compares well with analysis.
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...
In larval zebrafish Analgesic Screen One (AS1), is a small molecule analgesic that reverses the valence of noxious stimuli rendering these aversive attractive. this study, we evaluated potential AS1 in mice by measuring effects compound on behavioral models pain, locomotion and valence. We found selectively abolished second phase nocifensive behavior elicited chemical irritant formalin, while having no effect acute or inflammatory withdrawal thresholds evoked thermal mechanical stimuli....
Abstract Atomic spins are usually manipulated using radio frequency or microwave fields to excite Rabi oscillations between different spin states. These single-particle quantum control techniques that perform ideally with individual particles non-interacting ensembles. In many-body systems, inter-particle interactions unavoidable; however, can be used realize new schemes unique interacting systems. Here we demonstrate a scheme coherently and the states of an atomic Bose gas realizes...
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 reports results from a search for nucleon decay through invisible modes, where no visible energy is directly deposited during the itself, initial water phase of $\mathrm{SNO}+$. However, such decays within oxygen nucleus would produce an excited daughter that subsequently deexcite, often emitting detectable gamma rays. A rays yields limits $2.5\ifmmode\times\else\texttimes\fi{}{10}^{29}\text{ }\text{ }\mathrm{y}$ at 90% Bayesian credibility level (with prior uniform in rate)...
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.
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...
We describe here measurements with a new device, the ``dichroicon,'' Winston-style light concentrator built out of dichroic reflectors, which could allow large-scale neutrino detectors to sort photons by wavelength small overall loss. Photon sorting would benefit water or ice Cherenkov such as Hyper-Kamiokande IceCube providing measure dispersion, which, in turn, improved position reconstruction and timing. For scintillator like JUNO upgrades $\mathrm{SNO}+$ KamLAND-ZEN water-based liquid...
Experimental tests of Lorentz symmetry in systems all types are critical for ensuring that the basic assumptions physics well founded. Data from phases Sudbury Neutrino Observatory, a kiloton-scale heavy water Cherenkov detector, analyzed possible violations neutrino sector. Such would appear as one eight signal detector: six seasonal variations solar electron survival probability differing energy and time dependence two shape changes to oscillated spectrum. No evidence such signals is...
The CHErenkov / Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) LAB with 2g/L PPO as a fluor (LAB/PPO). This is first such demonstration for more challenging LAB/PPO cocktail improves on previous results LAB. A time resolution 338 +/- 12 ps FWHM an efficiency identifying photons 70 3% 63 8% time- charge-based separation, respectively, contamination 36 5% 38 4%. data consistent rise...
A search has been performed for neutrinos from two sources, the $hep$ reaction in solar $pp$ fusion chain and $\nu_e$ component of diffuse supernova neutrino background (DSNB), using full dataset Sudbury Neutrino Observatory with a total exposure 2.47 kton-years after fiducialization. The is both single-bin counting analysis likelihood fit. We find best-fit flux that compatible model predictions while remaining consistent zero flux, set one-sided upper limit $\Phi_{hep} <...
This paper reports results from a search for single and multi-nucleon disappearance the $^{16}$O nucleus in water within \snoplus{} detector using all of available data. These so-called "invisible" decays do not directly deposit energy but are instead detected through their subsequent nuclear de-excitation gamma-ray emission. New limits given partial lifetimes: $\tau(n\rightarrow inv) > 9.0\times10^{29}$ years, $\tau(p\rightarrow 9.6\times10^{29}$ $\tau(nn\rightarrow 1.5\times10^{28}$...
The $\mathrm{SNO}+$ experiment collected data as a low-threshold water Cherenkov detector from September 2017 to July 2019. Measurements of the 2.2-MeV $\ensuremath{\gamma}$'s produced by neutron capture on hydrogen were made using an Am-Be calibration source, for which large fraction emitted neutrons are simultaneously with 4.4-MeV $\ensuremath{\gamma}$. Analysis delayed coincidence between $\ensuremath{\gamma}$ and revealed detection efficiency that is centered around 50% varies at level...
Neutrons produced in nuclear interactions initiated by cosmic-ray muons present an irreducible background to many rare-event searches, even detectors located deep underground. Models for the production of these neutrons have been tested against previous experimental data, but extrapolation deeper sites is not well understood. Here we report results from analysis cosmogenically at Sudbury Neutrino Observatory. A specific set observables are presented, which can be used benchmark validity...
SNO+ is a large-scale liquid scintillator experiment with the primary goal of searching for neutrinoless double beta decay, and located approximately 2 km underground in SNOLAB, Sudbury, Canada. The detector acquired data two years as pure water Cherenkov detector, starting May 2017. During this period, optical properties were measured situ using deployed light diffusing sphere, improving model energy response systematic uncertainties. parameters included attenuation coefficients, effective...
Abstract Australian hospitals have prepared for a major surge in patients due to the infectious respiratory pandemic COVID‐19. In other nations, patient presentations overwhelmed resources. Ultrasound has been shown be an effective tool exclude significant life‐threats resource poor settings. this article, we will describe three lung ultrasound algorithms emergency diagnosis of presenting with symptoms during COVID‐19 pandemic: (i) LUSC19: assess severity COVID‐19; (ii) LUSAC: alternative...
The ability to separate Cherenkov and scintillation signals in liquid scintillator detectors would enable outstanding background rejection for next-generation neutrino experiments. Reconstruction of directional information, ring imaging, sub-Cherenkov threshold detection all have the potential substantially improve particle event identification. Cherenkov-Scintillation Separation (CHESS) experiment uses an array small, fast photomultipliers (PMTs) state-of-the-art electronics demonstrate...
Neutron production in giga electron volt--scale neutrino interactions is a poorly studied process. We have measured the neutron multiplicities atmospheric Sudbury Neutrino Observatory experiment and compared them to prediction of Monte Carlo simulation using genie minimally modified version geant4. analyzed 837 days exposure corresponding Phase I, pure heavy water, II, mixture Cl water. Neutrons produced were identified with an efficiency 15.3% 44.3%, for Phases I II respectively. The as...