Soft X-Ray Imaging System Used for Z-pinch Experiments

As an important imaging diagnostic manner in Z-pinch experiments, an X-ray streak camera can record a continuous time evolution of X-ray emission and has a better temporal resolution of about several picoseconds. Unfortunately, during experiment the transient strong electromagnetic noise produced by the device interferes with sensitive electronic components of the X-ray streak camera, making it unworkable frequently. In addition, the camera's position is close to the load chamber so that the photocathode and metallic grid of the camera may suffer the risk of being broken by high speed charged particles and exploding debris. In order to solve this problem, a novel soft X-ray streak imaging system based on the conversion of fast scintillator and an optical streak camera is designed. In the streak camera system, the plastic scintillator foil and fiber bundles are used to convert X-ray image into optical image and transmit it into an optical streak camera which is placed in a shielding cabinet far from the target chamber. The camera system proves efficient in avoiding the damage caused by high speed particles and suppressing the electromagnetic interference. The scope of response spectrum of the camera system is given by theoretical calculation and roughly from 0.2 to 10 keV. The spatial resolution of the camera system is designed to be less than 120 microns and the temporal resolution of the camera system is calibrated to be about 1 ns in X-pinch experiments. The camera system is used in aluminum wire-array experiments to capture the time-resolved and 1D space-resolved images of imploding plasmas. The spatiotemporal distribution information about the X-ray emission is presented. On the other hand, because of the transmission of the filter in sub-kilo-electron-volt emission, the spectral response of the camera system in the sub-kilo-electron-volt photon energy range decreases obviously, which affects the physical analysis of the image. In addition, because of the slow response time of the scintillator to Xrays, the temporal resolution of the camera system decreases obviously and is about1 ns. How to solve these problems will be carried out in the future work.