团簇尺度的瑞利散射测量中光电倍增管信号刻度与归一化处理

Calibration and Process of Singal of Photomultiplier Tube in Rayleigh Scattering of Supersonic Jet Clusters

利用光电倍增管测量团簇的瑞利散射,信号幅度与团簇源背压有关,也与光源强度和光电倍增管工作电压有关。当团簇源背压变化范围较大时,散射信号幅度变化可能导致光电倍增管信号超出线性范围。为此,在不同的光源强度、不同的工作电压下对光电倍增管输出信号进行了刻度,得到了输出信号幅度随光源强度、工作电压之间的关系。用此关系,对不同条件下的实验数据进行归一化处理,得到了团簇散射因子随团簇源背压的关系曲线,与同类实验和理论结果相符。

In the experiments of Rayleigh scattering of gas-jet clusters, the singal amplitude of PMT is not only affected by cluster itsself,but also by the intensity of light source and work voltage of PMT. When the back pressure of cluster source varies from 10 atm to about 100atm,the singal amplitude of PMT may be from linear to nonlinear. In order to solve the problem, signal calibration of PMT under different intensifies of light and voltage of PMT has been done. The relationship between the amplitude of signal and intensities of light as well as voltage of PMT has been obatained. The function of seater faeter of Ar clusters with the back pressure of cluster source is gotten experimentally, and agrees with related experimental and theoretical results.