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DOE OSTI · 2008250

Dose-Weighted Radiographic Source-Spot Size

Ekdahl, Jr., Carl August
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Abstract

The spatial resolution of a flash radiograph is determined by the time-integrated size of the radiation source. Since the radiation pulse includes the beam head and tail, which may be substantially larger than the beam body, the radiation source is larger than the focused flattop of the electron beam pulse. Moreover, the radiation dose rate is weighted by both beam current and electron energy, and it is the radiation dose that forms the radiograph image. Therefore, in order to estimate radiographic resolution from computer simulations of a focused electron beam, one should use a dose weighted moment analysis of the radiation source distribution. This approach is used to show that, in the absence of beam effects other than space-charge and emittance, radiographic resolution for Scorpius exceeds requirements, regardless of reasonable timing options for current and gap-voltage pulses.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Ekdahl, Jr., Carl August. 2023-10-09. Dose-Weighted Radiographic Source-Spot Size. https://doi.org/10.2172/2008250

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