Performance of an electromagnetically driven fast shutter system for plasma debris

A radiation simulator utilizing plasma radiation sources will generate large amount of undesirable debris which can potentially damage the frangible diagnosing detectors and the objects under test. An electromagnetically driven fast shutter for purpose of debris mitigation is developed, which erects a physical barrier to slow down the moving debris after allowing the passage of X-ray photons. The shutter system consists of a pair of thin metallic foils twisting the parallel axes, which is imploded by an outer magnetic field generated by a fast capacitor discharging into a single turn loop. Typical capacitor bank charging voltage is 20 kV, with a corresponding current of 80 kA and a discharging current period of 18 microseconds. A closure time as fast as 180 microseconds is observed with the effective cross-sectional area of 40 mm50 mm. The design and operation of the shutter system are described along with the measured results of closure times.