The PADME experiment at the LNF Beam Test Facility searches for dark photons produced in the annihilation of positrons with the electrons of a fix target. The strategy is to look for the reaction $e^{+}+e^{-}\rightarrow \gamma+A'$, where $A'$ is the dark photon, which cannot be observed directly or via its decay products. The electromagnetic calorimeter plays a key role in the experiment by measuring the energy and position of the final-state $\gamma$. The missing four-momentum carried away by the $A'$ can be evaluated from this information and the particle mass inferred. This paper presents the design, construction, and calibration of the PADME's electromagnetic calorimeter. The results achieved in terms of equalisation, detection efficiency and energy resolution during the first phase of the experiment demonstrate the effectiveness of the various tools used to improve the calorimeter performance with respect to earlier prototypes.

中文翻译：

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PADME 电磁量热仪的表征和性能

LNF 光束测试设施的 PADME 实验搜索在正电子与固定目标的电子湮灭时产生的暗光子。策略是寻找反应 $e^{+}+e^{-}\rightarrow \gamma+A'$，其中 $A'$ 是暗光子，不能直接或通过其衰变产物观察到。电磁量热仪通过测量终态$\gamma$的能量和位置，在实验中起到关键作用。由 $A'$ 带走的缺失的四动量可以从这些信息中进行评估，并推断出粒子质量。本文介绍了 PADME 电磁热量计的设计、构造和校准。在均衡方面取得的成果，