About

Professor Phillip S. Barbeau's research interests are predominantly in the fields of neutrino and astroparticle physics. His efforts are focused on studying the physics of coherent neutrino-nucleus scattering, conducting novel searches for dark matter in the universe, and searching for zero neutrino double beta decay. The unifying aspect of his work is the development of new and creative detectors to address some of the 'hard' problems in low-background rare-event detection. He is currently a Professor of Physics at Duke University, affiliated with the Trinity College of Arts & Sciences, and has been involved in research projects supported by the Department of Energy and other institutions. His contributions include advancing the understanding of neutrino properties, dark matter detection techniques, and technological innovations in detector development.

Research topics

• Physics
• Nuclear physics
• Optics
• Atomic physics
• Computer Science
• Particle physics
• Artificial Intelligence
• Condensed matter physics
• Algorithm
• Materials science
• Mathematics
• Medicine
• Chemistry

Selected publications

• First instrumented line of the Pacific Ocean Neutrino Experiment: status, development and outlook.

  2025-09-24

  articleOpen access

  The Pacific Ocean Neutrino Experiment (P-ONE) is a planned water-based Cherenkov neutrino telescope that will be located off the west coast of Canada. P-ONE will observe high-energy astrophysical neutrinos, aiming to identify the sources where they are produced, and will allow long-term in-situ studies of bioluminescence in the Cascadia Basin. The detector will be composed of instrumented mooring lines, which, along with the existing deep-sea infrastructure of the NEPTUNE observatory, make the design easily scalable. The first phase of the experiment, called P-ONE-1, is the first complete detector line and is instrumented with 20 modules spanning one kilometer. P-ONE-1 will serve as a test for all the newly developed systems and infrastructure and will pave the way for the future phases. This contribution will give an overview of the current status of the construction of the first line, the expected performance and the recent design innovations.

  PublisherOA PDFDOI

• Development of monitoring and control strategies for biofouling and sedimentation for the Pacific Ocean Neutrino Experiment

  2025-09-24

  articleOpen access

  The Pacific Ocean Neutrino Experiment (P-ONE) is a new neutrino telescope that is currently under construction in the North Pacific Ocean. The future location of the detector is the Cascadia Basin, a flat 2660 m deep region of ocean off the coast of Vancouver Island, Canada. P-ONE will be made up of one kilometre long strings of optical instrumentation. The collaboration is currently working towards the assembly and deployment of the first string. A pathfinder instrument took data at the P-ONE site from August 2018 until July 2023. Data from the pathfinder shows that upwards facing instruments lost some transparency over its 5 year lifetime. This is attributed to the deposition of marine sediments and subsequent colonization by biological organisms, collectively referred to as biofouling. Pathfinder results concerning biofouling will be discussed in this contribution. In addition, we will discuss the usage of surface modifying coatings for biofouling mitigation on future P-ONE instruments. The inclusion of this technology is novel for neutrino telescopes and a candidate coating will be tested in-situ on the first string.

  PublisherOA PDFDOI

• Prototype acoustic positioning system for the Pacific Ocean Neutrino Experiment

  Journal of Instrumentation · 2025-07-01 · 1 citations

  articleOpen accessCorresponding

  Abstract We present the design and initial performance characterization of the prototype acoustic positioning system intended for the Pacific Ocean Neutrino Experiment. It comprises novel piezo-acoustic receivers with dedicated filtering- and amplification electronics installed in P-ONE instruments and is complemented by a commercial system comprised of cabled and autonomous acoustic pingers for sub-sea installation manufactured by Sonardyne Ltd. We performed an in-depth characterization of the acoustic receiver electronics and their acoustic sensitivity when integrated into P-ONE pressure housings. These show absolute sensitivities of up to -125 dB re V 2 /μPa 2 in a frequency range of 10–40 kHz. We furthermore conducted a positioning measurement campaign in the ocean by deploying three autonomous acoustic pingers on the seafloor, as well as a cabled acoustic interrogator and a P-ONE prototype module deployed from a ship. Using a simple peak-finding detection algorithm, we observe high accuracy in the tracking of relative ranging times at approximately 230–280 μs at distances of up to 1600 m, which is sufficient for positioning detectors in a cubic-kilometer detector and which can be further improved with more involved detection algorithms. The tracking accuracy is further confirmed by independent ranging of the Sonardyne system and closely follows the ship's drift in the wind measured by GPS. The absolute positioning shows the same tracking accuracy with its absolute precision only limited by the large uncertainties of the deployed pinger positions on the seafloor.

  PublisherDOI

• Status update of various simulation components for P-ONE.

  2025-09-24

  articleOpen access

  The Pacific Ocean Neutrino Experiment (P-ONE) is a planned cubic-kilometer-scale Cherenkov neutrino telescope that will be deployed off the West Coast of Canada. To evaluate the perfor- mance of the telescope and support future analyses, it is essential to have accurate simulations of neutrino interactions and background sources. This contribution provides an overview of the current status of various components used in water-based neutrino telescope simulation. These include characterization and simulation of backgrounds, including 40K decays and biolumines- cence, studies on the simulation of muons, neutrinos, and cascade generation, as well as new photon propagation techniques. In particular, emphasis will be given to recent developments that are tailored specifically for P-ONE.

  PublisherOA PDFDOI

• Evidence of Coherent Elastic Neutrino-Nucleus Scattering with COHERENT’s Germanium Array

  Physical Review Letters · 2025-06-09 · 23 citations

  articleOpen access

  We report the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on natural germanium, measured at the Spallation Neutron Source at Oak Ridge National Laboratory. The Ge-Mini detector of the COHERENT collaboration employs large-mass, low-noise, high-purity germanium spectrometers, enabling excellent energy resolution, and an analysis threshold of 1.5 keV electron-equivalent ionization energy. We observe an on-beam excess of 20.6_{-6.3}^{+7.1} counts with a total exposure of 10.22 GWhkg, and we reject the no-CEvNS hypothesis with 3.9σ significance. The result agrees with the predicted standard model of particle physics signal rate within 2σ.

  PublisherOA PDFDOI

• Pacific Ocean Neutrino Experiment first string trigger and data acquisition systems

  2025-09-26

  articleOpen access

  The Pacific Ocean Neutrino Experiment (P-ONE) is set to deploy its first detection string in the Cascadia Basin off the coast of British Columbia, Canada. As a next-generation Cherenkov neutrino telescope, P-ONE will be sensitive to ultra-high-energy neutrinos (10³–10⁸ GeV) from astrophysical sources. To effectively capture these rare physics signatures, the experiment's trigger system must operate in a high-background environment dominated by K40 decay and bioluminescence. This poster presents the design and integration of the P-ONE trigger system, which spans multiple levels of data acquisition (DAQ). The trigger must seamlessly interface with both the slow detector controlling Maximum Integrated Data Acquisition System (MIDAS) and the back-end fastDAQ system to select and preliminarily cluster events. The trigger system operates in a hierarchical fashion: first, an initial firmware (L0) trigger identifies candidate events, which are then refined by a physics trigger that requests additional waveform data from neighboring modules. Onshore, these waveform packets and timing information are assembled into full events for storage and analysis. This talk will detail the trigger chain, with a focus on bioluminescence mitigation and physics-driven event selection, as well as its integration with the DAQ and Run Control systems.

  PublisherOA PDFDOI

• Search for Double Beta Decays of $^{134}$Xe with EXO-200 Phase II

  ArXiv.org · 2025-11-17

  preprintOpen access

  EXO-200 was a leading double beta decay experiment consisting of a single-phase, enriched liquid xenon time projection chamber filled with an admixture of 80.672% $^{136}$Xe and 19.098% $^{134}$Xe. The detector operated at WIPP between 2010 and 2018 and was designed to search for double beta decay of $^{136}$Xe. Data was acquired in two phases separated by a period of detector upgrades. We report on the search for $0νββ$ and $2νββ$ decay of $^{134}$Xe with Phase II EXO-200 data, with median 90% C.L. exclusion sensitivity $T_{1/2}^{0ν} \geq 3.7\times 10^{23}$ yr and $T_{1/2}^{2ν} \geq 2.6 \times 10^{21}$ yr, respectively. No statistically significant signal is observed for either decay mode. We set a world-leading lower limit on the half-life of the neutrinoless decay mode of $^{134}$Xe of $T_{1/2}^{0ν} \geq 8.7\times10^{23}$ (90% C.L.) and the second strongest constraint on the two-neutrino decay of $T_{1/2}^{2ν} \geq 2.9\times10^{21}$ (90% C.L.), a 3-fold improvement over the EXO-200 Phase I measurement. New constraints are also set for the $2νββ$ and $0νββ$ decays of $^{134}$Xe to the lowest excited state of $^{134}$Ba.

  PublisherOA PDFDOI

• Development and testing of the optical module for the Pacific Ocean Neutrino Experiment (P-ONE)

  2025-09-24

  articleOpen access

  The P-ONE (Pacific Ocean Neutrino Experiment) is a future cubic-km-scale, water Cherenkov neutrino telescope that will be located in the Pacific Ocean off the coast of Canada. This telescope will contribute to the search for astrophysical neutrino sources, test improved detection and calibration techniques, and provide valuable oceanographic measurements. The first line of the detector, named P-ONE-1, is currently under production.The first line of the detector, named P-ONE-1, is currently in production. The P-ONE Optical Module (P-OM) consists of sixteen 3-inch photomultiplier tubes (PMTs), as well as a series of calibration devices (flashers, acoustic devices, axicons and muon scintillators), which will be used to characterise the optical properties of water and measure the initial performance of the line. The PMT waveforms are digitzed by a 16-channel (210 MHz) analog-to-digital converter (ADC) with a timing system providing an estimated accuracy of 0.1 ns. After assembling the P-OM, it will be essential to characterise and calibrate the different photosensors in order to create an accurate simulation of the mooring line and verify that the modules function properly. Therefore, at the Technical University of Munich a dedicated automatic calibration setup consisting of multiple light sources and a rotation stage was developped to perform quality control of the P-OM hemispheres and measure the properties of the PMTs. This contribution will discuss the different feature and subsystem of the optical module and its measured performance.

  PublisherOA PDFDOI

• In Situ Calibration Systems for the Pacific Ocean Neutrino Experiment

  2025-09-24

  articleOpen access

  The Pacific Ocean Neutrino Experiment (P-ONE) is a cubic-kilometer scale neutrino telescope to be deployed in the northern Pacific Ocean off the West Coast of Canada. P-ONE will observe high-energy neutrinos using an array of kilometer tall mooring lines instrumented with P-ONE Optical Modules (P-OMs) which detect Cherenkov light from neutrino-induced secondary particles within the detector volume. To accurately understand the signals from incident neutrinos, the optical properties of seawater, detector geometry, and optical backgrounds must be precisely calibrated. However, the ocean is a dynamic environment where these parameters can vary over time. To achieve this goal, P-ONE includes a variety of calibration systems for both localized and ranged real time detector calibration measurements. These include integrated small, fast light flashers for optical inter-module measurements, acoustic receivers for spatial trilateration, and auxiliary sensors for tilt and orientation measurements. The acoustic positioning system is further complemented with autonomous and cabled acoustic pingers on the seafloor. In addition, some P-OMs in the detector are designed as hybrid calibration modules (P-CALs) which additionally contain long-range, isotropic nanosecond light flashers and cameras. This talk highlights the simulation, development, and field testing of all P-ONE calibration systems

  PublisherOA PDFDOI

• Accessing new physics with an undoped, cryogenic CsI CEvNS detector for COHERENT at the SNS

  Physical review. D/Physical review. D. · 2024-05-10 · 10 citations

  articleOpen access1st authorCorresponding

  We consider the potential for a 10 kg undoped cryogenic CsI detector operating at the Spallation Neutron Source to measure coherent elastic neutrino-nucleus scattering and its sensitivity to discover new physics beyond the standard model (BSM). Through a combination of increased event rate, lower threshold, and good timing resolution, such a detector would significantly improve on past measurements. We considered tests of several BSM scenarios such as neutrino nonstandard interactions and accelerator-produced dark matter. This detector’s performance was also studied for relevant questions in nuclear physics and neutrino astronomy, namely the weak charge distribution of Cs and I nuclei and detection of neutrinos from a core-collapse supernova. Published by the American Physical Society 2024

  PublisherOA PDFDOI

Frequent coauthors

• V. Belov

  218 shared

• J. Runge

  136 shared

• M. P. Green

  Triangle Universities Nuclear Laboratory

  134 shared

• A. Konovalov

  127 shared

• S. Hedges

  Lawrence Livermore National Laboratory

  126 shared

• T. Brunner

  McGill University

  123 shared

• R. Gornea

  123 shared

• C. Awe

  111 shared

Education

• PhD, Physics

  University of Chicago

  2009

• B.A., Physics

  University of Chicago

  2001

• B.S., Mathematics

  University of Chicago

  2001