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On “S-300” generator (700 kV, 4MA, 70 ns) at the Kurchatov Institute, the experimental studies with multi-material wire array units are carried on aimed at creating the powerful X-ray source. The development of new diagnostic methods would definitely contribute to attain new data, which could help in explanation of X-ray emission mechanism of imploding multi-wire arrays that has not well understood yet. The experimental study of soft X-ray emission of different wire sets, different in both mass and composition, has been carried on in the same geometry. One of the purposes of these experiments was investigation of the wire array chemical composition influence on the implosion dynamics and stability.

A new type of surface flashover switch, suitable for multiplex pulse generation, is studied. The switch is composed of several parallel rail gaps (PRGs). Each multistage PRG is composed of several serial subgroup gaps (SSG) formed by intermediate electrodes. The trigger electrode of the switch is a common electrode isolated from the main discharge circuit and located parallel to the central line of PRGs. The multistage scheme of PRG is helpful to multi-channel discharge. The switch has some advantages, such as a low jitter, low conduct inductance and short switching time. These advantages and the multiplex scheme make the switch suitable for short frontal rising time pulse formation and accurate synchronization for a multi-module parallel operation device. In a primary test, the jitter of the switch is about 3.3 ns. It has been applied in a linear transformer device successfully.

On "S-300" generator (700 kV, 4 MA, 70 ns) at the Kurchatov Institute, the experimental studies with multi-material wire array units are carried on aimed at creating the powerful X-ray source. The development of new diagnostic methods would definitely contribute to attain new data, which could help in explanation of X-ray emission mechanism of imploding multi-wire arrays that has not well understood yet. The experimental study of soft X-ray emission of different wire sets, different in both mass and composition, has been carried on in the same geometry. One of the purposes of these experiments was investigation of the wire array chemical composition influence on the implosion dynamics and stability.

Magnetically driven loading technology is to load the large pulse current to the test area through the pulsed power, which forms a smooth magnetic pressure rising over time to achieve a quasi-isentropic compression of sample and hyper-velocity flyer launch. Based on the output characteristics and parameters of PTS accelerator, two types of hyper-velocity flyer launch experiments with different load configurations, such as the load, flyer plates size, current waveform and diagnostic systems etc, are designed and tested. LY12 aluminum flyer plates with dimensions of 10 mm0.725 mm was launched by single-sided stripline load configuration to 11.5 km/s while the magnetic drive load pressure is near 0.9 10^5 MPa. Simulation and experimental results agrees well with those of in the flyer launch process and the ultimate velocity. Further simulation shows that the launch velocity of aluminum flyer plates with dimensions of 8.5 mm1 mm is expected to exceed 15 km/s under the program of optimizing the structural parameters and regulation. The design and experiment technology of hyper-velocity flyer launch based on multi-branch pulsed power generator has been mastered during the designs and experiments.

In this paper, we represent the radiation characteristics of electromagnetic pulse generated by Z pinch implosion. Magnetic energy which couples with motions of metallic wire arrays or solid liners driven by Z pinch can radiate away. Theoretical results indicate that the radiation power of electromagnetic pulse is determined by both load current and implosion trace. Experiments are carried on primary test stand facility at Institute of Fluid Physics where a current rising to 7 MA in (10%–90%) 65 ns is used to drive a wire array Z pinch. The measured load current and implosion trace show that the Z pinch can deliver about 1 GW, 10 ns full width, 20–70 MHz central frequency, broadband electromagnetic pulse with an energy conversion efficiency of 10-7. Parameters of electromagnetic pulse are much smaller than those of X-ray with a power of 50 TW and an energy of 0.5 MJ. In the approximation of weak relativistic case, the power of electromagnetic pulse which is proportional to sixth power of load current, dramatically increases with current increasing. Soft X-ray radiation is an important channel for dissipating a considerable fraction of energy provided by facility. The results presented here demonstrate that electromagnetic pulse emission in the case of higher load current can cause significant damage to diagnostic devices. Moreover, intense electromagnetic pulse produced by this method may have many potential applications.

In the form of joint experiment between China and Russia, the experimental studies of Zpinches of mixed wire array of aluminum (A1) and tungsten (W) were carried out on S-300 generator,which was located on Kurchatov Institute of Russia. The experimental results were compared with those of single A1 array and single W array, respectively. There are obvious difference between mixed one and single one in their photon spectral distributions. The intensity of K-series emission lines from the mixed wire array Z-pinch is lower than that from single A1 array. The radiated lines with wavelengths less than 1.6nm were not found in single W array Z-pinches. In the Z-pinch processes, the area radiating x-arys in mixed wire array is smaller than that of single A1 array, but is larger than that of single W array. The radiated energy from mixed wire array Z-pinch is higher than that from single A1 array, but is slightly lower than that from single W array. The FWHM of x-ray pulse with a maximal power 0.3—0.5TW and total energy 10—20kJ is about 25ns, which radiated from Z-pinches with a radial convergence of 4—5 on S-300 generator. The shadow photograph of the mixed wire-array Z-pinch plasma by laser probe shows that the core-corona configuration was formed and the corona was moving toward the center axis during the wire-array plasma formation, that the interface of the plasma is not clear, and that therer are a number of structures inside. They also suggests that there was an obvious development of Magneto Rayleigh-Taylor instability in the Z-pinch process as well.