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Register a new userA new compact, portable 2-LTD-brick x-pinch driver at the Idaho Accelerator Center: design, fabrication, testing and x-ray performance
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Authors
Roman V. Shapovalov
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We propose to construct a compact and portable x-pinch driver with x-ray radiation performance, comparable to standard x-pinch drivers. Such a new x-pinch driver was recently designed, fabricated and tested at the Idaho Accelerator Center. The generator is based on two slow LTD bricks combined into one solid unit, and can be described by a simple RLC circuit with four fast 140-nF, 100-kV capacitors that store up to 2.8 kJ. The test data reveals that when charged to 80 kV, the driver supplies 185-kA peak-current into a short Ni-wire load with 220-ns, 10-90%, rise time. The total internal inductance of our driver was measured to be about 60 nH. The revised driver model shows that when fully charged to 100 kV, the driver will supply 180-kA peak-current with 150-ns rise-time into the x-pinch load. The corresponding current rise rate is about 1.2 kA/ns. To prove the driver x-pinch efficiency and to estimate the x-ray radiation performance, we could, for example, image an exploding wires, placed in a separate HV pulser, with our x-pinch x-ray radiation source. The study of exploding wires helps to understand the behavior of a warm dense matter, and our x-pinch driver can be part of the diagnostics needed for this study which is currently under progress at the IAC. Our driver contains no oil inside, is very compact and portable, and can be easily relocated to practically anywhere, which makes it an ideal backlighting diagnostic tool in many areas of plasma physics, biology, and industry where a bright, fast, and small x-pinch radiation source is required.
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Almost all well-known x-pinch x-ray radiation machines are large, based on a conventional Marx generator, and lack portability. The literature suggests that a current rate of rise of 1 kA/ns or more is required for good x-pinch radiation performance, which, for reasonable current rise times, translates to a current requirement of 100 kA or more. Those requirements are difficult to achieve in a limited volume, if one wants to build a compact machine without the use of traditional Marx generators, pulse-forming lines, and transmission lines. In this work we describe a new, compact and portable x-pinch driver based on two slow LTD bricks combined into one solid unit. The short-circuit tests demonstrated the required 1-kA/ns current rate-of-rise and x-pinch shots confirmed good x-pinch radiation performance and revealed the potential for many x-pinch applications.
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