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arXiv · 2409.14691

Measurements of a LYSO crystal array from threshold to 100 MeV

O. Beesley·J. Carlton·B. Davis-Purcell·D. Ding·S. Foster·K. Frahm·L. Gibbons·T. Gorringe·D. W. Hertzog·S. Hochrein·J. Hui·P. Kammel·J. LaBounty·J. Liu·R. Roehnelt·P. Schwendimann·A. Soter·E. Swanson·B. Taylor
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Abstract

We report measurements of ten custom-made high-homogeneity LYSO crystals. The investigation is motivated by the need for a compact, high-resolution, and fast electromagnetic calorimeter for a new rare pion decay experiment. Each $2.5\times 2.5 \times 18$ cm$^3$ crystal was first characterized for general light yield properties and then its longitudinal response uniformity and energy resolution were measured using low-energy gamma sources. The ten crystals were assembled as an array and subjected to a 30 - 100 MeV positron beam with excellent momentum definition. The energy and timing resolutions were measured as a function of energy, and the spatial resolution was determined at 70 MeV. An additional measurement using monoenergetic 17.6 MeV gammas produced through a p-Li resonance was later made after the photosensors used in positron testing were improved. As an example of the results, the energy resolution at 70 MeV of 1.52 $\pm$ 0.03% is more than two times better than reported results using previous generation LYSO crystals.

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O. Beesley, J. Carlton, B. Davis-Purcell, D. Ding, S. Foster, K. Frahm, L. Gibbons, T. Gorringe, D. W. Hertzog, S. Hochrein, J. Hui, P. Kammel, J. LaBounty, J. Liu, R. Roehnelt, P. Schwendimann, A. Soter, E. Swanson, B. Taylor. 2024-09-23. Measurements of a LYSO crystal array from threshold to 100 MeV. https://arxiv.org/abs/2409.14691

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