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arXiv · 2605.25301

Commissioning of the large-scale lead tungstate scintillating calorimeter

A. Somov·V. V. Berdnikov·L. Gan·P. V. Laveen·A. Smith·S. Taylor·H. Voskanyan
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Abstract

This article reports on the installation and initial commissioning of a large-scale lead tungstate (PbWO4) scintillating crystal calorimeter developed for high-rate photon detection and precise energy measurement. The calorimeter comprises 1,596 high-granularity, high-resolution scintillating crystals optimized for electromagnetic-shower detection over a wide energy range. Scintillation light from each crystal is read out by Hamamatsu R4125 photomultiplier tubes equipped with a custom voltage divider and front-end amplifier to ensure stable gain at high rates. All calorimeter modules were fabricated and characterized using an LED-based optical test system prior to installation to verify uniformity and photodetector performance. After installation, the ECAL was fully integrated into the experiment data acquisition and energy-based trigger systems. The optical response of the modules was equalized using the light-monitoring system, cosmic-ray muons, and photons from Compton-scattering events. Commissioning results demonstrate a reliably calibrated optical response and stable detector performance during the first run. These results validate the calorimeter design and commissioning methodology for large-scale scintillator-based photonic instrumentation.

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A. Somov, V. V. Berdnikov, L. Gan, P. V. Laveen, A. Smith, S. Taylor, H. Voskanyan. 2026-05-24. Commissioning of the large-scale lead tungstate scintillating calorimeter. https://doi.org/10.1117/1.oe.65.5.054107

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