In this work, the physical dimensions and the actual position of germanium crystal within a detector housing, the homogeneity of the crystal surface and outer dead layer thickness for a p-type HPGe detector were confirmed by the scan method using the collimated low energy photon beams combined with Monte Carlo simulation. The length and the diameter of the crystal were found to match with the values supplied by the manufacturer in discrepancy of about 3%. Only one mounting strap (Typical) for holding the crystal inside the mounting cup instead of two which is indicated in the detector drawing supplied by manufacturer was revealed by scanning along the lateral face of detector. Scanning on the front surface and around the lateral face of detector by the collimated 59.5 keV photon beam verified the outer dead layer thicknesses at the front surface and lateral face of the crystal averagely increases about 6.5% and 12% respectively. Adjusting the detector parameters for MCNP simulation by these verified values, the simulated peak efficiencies for different photon energies become being in accordance with the experimental peak efficiencies.

在这项工作中，通过准直的低能光子束的扫描方法，确定了锗晶体在探测器外壳内的物理尺寸和实际位置，p型HPGe探测器的晶体表面均匀性和外死层厚度。结合蒙特卡洛模拟。发现晶体的长度和直径与制造商提供的值相符，相差约3％。通过沿检测器侧面扫描，只露出了一条用于将晶体固定在安装杯中的固定带（典型），而不是制造商提供的检测器图中显示的两条固定带。通过准直器59在探测器的正面和侧面进行扫描。5 keV光子束验证了晶体正面和侧面的外死层厚度分别平均增加了约6.5％和12％。通过这些验证值调整用于MCNP模拟的检测器参数，针对不同光子能量的模拟峰值效率将与实验峰值效率保持一致。