短语词组短语bremsstrahlung thick -target 厚靶制动辐射thick -target yield measurement 厚靶实验方法thick TiDx target TiDx 厚靶thick Be target 厚铍靶Thick -target Yield 厚靶产额infinitely thick target 无限厚靶thick target model 厚靶模型 返回 thick target