The Belle II experiment at the SuperKEKB accelerator is the new-generation intensity frontier electron-positron colliding beam experiment. The electromagnetic calorimeter consisting of 8736 CsI(Tl) crystals with their PIN-photodiode readout, has been inherited from the Belle experiment. In order to achieve high rate capability and immunity against beam background, the electronics has been upgraded to feature waveform sampling readout to provide not only energy deposition but also timing for each crystal hit. Design and construction of the upgraded electronics are reviewed and the performance in the early Belle II physics runs is reported. We also present the first application of calorimeter pulse shape discrimination at a B-Factory experiment. This novel technique, enabled by the new waveform sampling electronics, allows for discrimination between electromagnetic and hadronic showers, leading to significant improvements in kaon-long vs. photon separ...

中文翻译：

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Belle II电磁热量计及其在SuperKEKB早期运行期间的性能

SuperKEKB加速器上的Belle II实验是新一代强度前沿电子-正电子碰撞束实验。电磁热量计由8736个CsI（Tl）晶体组成，其PIN光电二极管读数已从Belle实验继承而来。为了实现高倍率性能和对光束背景的抵抗力，电子设备已升级为具有波形采样读数功能，不仅可以提供能量沉积，而且还可以为每个晶体命中提供定时。审查了升级后的电子设备的设计和构造，并报告了Belle II早期物理实验的性能。我们还在B工厂实验中展示了量热仪脉冲形状判别的首次应用。这项新技术由新的波形采样电子设备实现，