神光Ⅱ各级放大器小信号增益的在线测量

神光Ⅱ装置精密化功率平衡要求8路子光束的输出能量平衡和脉冲波形一致，即每条放大链的增益和透过率相同。但装置因日常打靶工作需要，8路子光束放大链中同级放大器的增益能力差异较大。针对该问题，利用一种精度优于1％的小能量测量系统，对神光Ⅱ装置8路四级放大器的小信号增益进行在线测量，分别得到了40，70棒状放大器，100片状放大器和200双层片状放大器在正常工作电压下的小信号增益值，掌握了每路各级放大器的增益特性，精确量化了各路同级放大器的差异，为神光Ⅱ精密化功率平衡调试提供了宝贵的实验数据。

Research of Small Signal Gain Online Measurement in Amplifiers of SG-Ⅱ

For precision SG-Ⅱ power balance, there must have same output energy and output pulse waveform in the 8 beams, it means that the gain and transmissivity in every amplifier chain are same. But the gain abilities of the same type amplifiers in 8 beams are different for needing of daily operation. It was a first time that small signal gain of different amplifiers in SG-Ⅱ were measured online by using a small energy measurement system which has superior 1% precision. The small signal gain values of 40 and 70 rod amplifiers, 100 slab amplifiers and 200 double slab amplifiers are got in the regular working voltages. The differences of the same type amplifiers are quantized and that provides valuable experimental data to power balance in SG-Ⅱ precision.