A divergent gas-puff Z pinch has been devised for the realization of an efficient soft x-ray point source. In this device, a divergent hollow annular gas puff is ejected outward from the surface of the inner electrode, and the plasma is compressed three-dimensionally to generate a soft x-ray point source. In the SHOTGUN III-U device at Nihon University, the power supply was enhanced, and experiments were conducted over a larger current range. The peak current at the charging voltage of −25 kV was −190 kA. Ar was used as the discharge gas. The self-contraction process of the plasma was investigated in detail using a gated camera. Near the peak current, local contraction occurred in front of the inner electrode. The contraction velocity of the plasma was 5.5 × 104 m/s. As the plasma contracted, the discharge current decreased. The energy input was analyzed by induction acceleration. The net input energy was found to be 750 J, which corresponded to 13.3% of the stored energy of the capacitor, 5630 J. The soft x-ray source was observed using a soft x-ray CCD camera. A point source was observed 7 mm in front of the inner electrode. The size of the source was 35 µm in the axial direction and 14 µm in the radial direction.

中文翻译：

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SHOTGUN III-U发散式喷气Z夹点中的自收缩过程和热点形成

为了实现高效的软 X 射线点源，设计了一个发散的喷气 Z 夹点。在该装置中，从内电极表面向外喷出发散的中空环状气体，等离子体被三维压缩，产生软X射线点源。在日本大学的 SHOTGUN III-U 设备中，增强了电源，并在更大的电流范围内进行了实验。-25 kV 充电电压下的峰值电流为 -190 kA。Ar用作放电气体。使用门控相机详细研究了等离子体的自收缩过程。在峰值电流附近，内部电极前发生局部收缩。等离子体的收缩速度为 5.5 × 104 m/s。随着等离子体收缩，放电电流减小。通过感应加速度分析能量输入。发现净输入能量为 750 J，相当于电容器储存能量 5630 J 的 13.3%。使用软 x 射线 CCD 相机观察软 x 射线源。在内电极前 7 毫米处观察到点源。源的尺寸在轴向为 35 µm，在径向为 14 µm。