GRANDProto35 is the first stage of the GRAND project. It will be composed of an array of 35 radio antennas and 24 scintillation detectors in which the radio and scintillating subarrays will be triggered independently. The scintillation detector array allows to cross-check the radio array, thus quantitatively determine its detection efficiency. The photomultiplier of Hamamatsu R7725 is a candidate for the scintillation detector. The characteristics of the PMT will directly affect the resolution of the time and energy measurements and the dynamic detection range of a scintillation detector. A voltage divider circuit featured with dual-readout was designed for the PMT to cover a larger linear dynamic range (LDR). Some characteristics of the PMT were calibrated and investigated: the absolute gain, single photoelectron (SPE) energy resolution, transit time spread (TTS), linear dynamic range, and temperature dependence of the PMT gain. In this paper, details about the system setup, measurement methods, and results will be described.

GRANDProto35 是 GRAND 项目的第一阶段。它将由 35 个无线电天线和 24 个闪烁探测器组成，其中无线电和闪烁子阵列将独立触发。闪烁探测器阵列允许交叉检查无线电阵列，从而定量确定其探测效率。Hamamatsu R7725 的光电倍增管是闪烁探测器的候选者。PMT 的特性将直接影响时间和能量测量的分辨率以及闪烁探测器的动态探测范围。为 PMT 设计了具有双读出功能的分压器电路，以覆盖更大的线性动态范围 (LDR)。校准和研究了 PMT 的一些特性：绝对增益、单光电子 (SPE) 能量分辨率、传输时间扩展 (TTS)、线性动态范围和 PMT 增益的温度依赖性。本文将详细介绍系统设置、测量方法和结果。