Engineering topics

Bourgeois, C.

Publications and source records attributed to Bourgeois, C..

5 records

DOE OSTI2026

Muon tracking in a LiquidO opaque scintillator detector

LiquidO is an innovative radiation detector concept. The core idea is to exploit stochastic light confinement in a highly scattering medium to self-segment the detector volume. In this paper, we demonstrate event-by-event muon tracking in a LiquidO opaque scintillator detector prototype. The detector consists of a 30 mm cubic scintillator volume instrumented with 64 wavelength-shifting fibres arranged in an 8 × 8 grid with a 3.2 mm pitch and read out by silicon photomultipliers. A wax-based opaque scintillator with a scattering length of approximately 0.5 mm is used. The tracking performance of this LiquidO detector is characterised with cosmic-ray muons and the position resolution is demonstrated to be 450 μm per row of fibres. These results highlight the potential of LiquidO opaque scintillator detectors to achieve fine spatial resolution, enabling precise particle tracking and imaging.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2025

COCOA: A compact Compton camera for astrophysical observation of MeV-scale gamma rays

COCOA (COmpact COmpton cAmera) is a next-generation gamma-ray telescope designed for astrophysical observations in the MeV energy range. The detector comprises a scatterer volume employing the LiquidO detection technology and an array of scintillating crystals acting as absorber. Surrounding plastic scintillator panels serve as a veto system for charged particles. The detector's compact, scalable design enables flexible deployment on microsatellites or high-altitude balloons. Gamma rays at MeV energies have not been well explored historically (the so-called "MeV gap") and COCOA has the potential to improve the sensitivity in this energy band.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2024

The DAMIC-M Low Background Chamber

The DArk Matter In CCDs at Modane (DAMIC-M) experiment isdesigned to search for light dark matter (m$_{χ}$ < 10 GeV/c$^{2}$)at the Laboratoire Souterrain de Modane (LSM) in France. DAMIC-Mwill use skipper charge-coupled devices (CCDs) as a kg-scale activedetector target. Its single-electron resolution will enable eV-scaleenergy thresholds and thus world-leading sensitivity to a range ofhidden sector dark matter candidates. A DAMIC-M prototype, the LowBackground Chamber (LBC), has been taking data at LSM since2022. The LBC provides a low-background environment, which has beenused to characterize skipper CCDs, study dark current, and measureradiopurity of materials planned for DAMIC-M. It also allows testingof various subsystems like readout electronics, data acquisitionsoftware, and slow control. This paper describes the technicaldesign and performance of the LBC.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2024

Characterization of a radiation detector based on opaque water-based liquid scintillator

Here, we present the characterization of a novel radiation detector based on an opaque water-based liquid scintillator. Opaque scintillators, also known as LiquidO, are made to be highly scattering, such that the scintillation light is effectively confined, and read out through wavelength-shifting fibers. The 1-liter, 32-channel prototype demonstrates the capability for both spectroscopy and topological reconstruction of point-like events. The design, construction, and evaluation of the detector are described, including modeling of the scintillation liquid optical properties and the detector’s response to gamma rays of several energies. A mean position reconstruction error of 4.4 mm for 1.6 MeV-equivalent events and 7.4 mm for 0.8 MeV-equivalent events is demonstrated using a simple reconstruction approach analogous to center-of-mass.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Gulf ribbed mussels increase plant growth, primary production, and soil nitrogen cycling potential in salt marshes

Smooth cordgrass Spartina alterniflora and Atlantic ribbed mussels Geukensia demissa have a mutualism whereby S. alterniflora provides substrate and shade for G. demissa while G. demissa enhances S. alterniflora growth and drought tolerance. Together, these species improve salt marsh stability and function. To better understand if a similar relationship exists between S. alterniflora and Gulf ribbed mussels G. granosissima in salt marshes of the Gulf of Mexico, we conducted a manipulative experiment with identical starting plant density and varying densities of G. granosissima and monitored plant and soil responses over a growing season. We found that S. alterniflora stem and leaf density was 1.5 and 1.9 times greater for the highest mussel biomass compared to the lowest mussel biomass treatments. Similarly, above- and below-ground biomass were 2.6 and 3.2 times greater for the highest mussel biomass compared to the lowest mussel biomass treatments. More and larger S. alterniflora at higher G. granosissima densities resulted in 2 and 4 times the S. alterniflora gross CO 2 uptake and respiration rate, respectively. Methane fluxes were highest when G. granosissima were present, likely driven by the positive relationship between methane flux and belowground biomass. Net potential nitrification was 5 times higher for the highest mussel biomass compared to the lowest mussel biomass treatments, and denitrification rates were 1.8 times higher. Ultimately, our results suggest that G. granosissima increases S. alterniflora growth and productivity, much like the positive relationship between G. demissa and S. alterniflora , which in turn influences salt marsh stability and function.

Environmental Sciences & Ecology↗