A Large Area Picosecond Photodetector for Neutron Transmission Measurements at DICER at LANSCE

Journal Article · 09 June 2023 · IEEE Transactions on Nuclear Science

DOI: https://doi.org/10.1109/tns.2023.3285068 · OSTI ID:1998127

Stamatopoulos, Athanasios  ^[1]; Couture, A.  ^[1]; DiGiovine, B.  ^[1]; Koehler, P. ^[1]; Rusev, G. ^[1]

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1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

The Device for Indirect Capture Experiments on Radionuclides (DICER) is a new instrument that is being developed at the Los Alamos Neutron Science Center (LANSCE) to study neutron capture reactions on short-lived radionuclides. To achieve that, DICER is using an indirect technique based on measuring the neutron transmission through very small samples (0.12–1.2 mm in diameter, $$\mu \text{g}$$ -mg in mass). The main detection system of DICER consists of two dual photomultiplier (PMT)-based detectors which are sensitive to the scintillation light produced when neutrons interact with ⁶ Li glass disks. DICER is developing a new collimation system that includes a 0.1-mm collimator. In such small sizes, the need for neutron beam imaging is crucial and necessary to confirm the appropriate alignment between the irradiated sample and the neutron detectors. The large area picosecond photodetector (LAPPD) is a multichannel plate (MCP)-based photodetector, with picosecond-level timing, single-photon detection capabilities, and spatial resolution of the order of 1 mm. Coupling the LAPPD with a ⁶ Li glass scintillator results in a neutron imaging detector. The first irradiation of the LAPPD at DICER indicated that apart from imaging the beam, the LAPPD can be used as the main neutron detection system. Furthermore, these results were proof of principle measurements demonstrating the capabilities of the beamline, and the challenge with small samples will be addressed in the future. The first efforts and developments, including irradiations of the LAPPD and the first beam images, will be presented.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: 89233218CNA000001; 20200108DR
• OSTI ID: 1998127
• Report Number(s): LA-UR-22-31612; TRN: US2405357
• Journal Information: IEEE Transactions on Nuclear Science, Vol. 70, Issue 7; ISSN 0018-9499
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English