The Trailmaster/Pioneer 1 series of imploding plasma experiments are aimed at using an inductive storage driver to implode an ultrathin aluminum foil with a multimegampere, submicrosecond electrical pulse. The power pulse is produced by an explosive flux compression generator and a fast plasma compression opening switch. The goal is to obtain an intense source of soft x rays from the thermalization of the plasma kinetic energy when pinch occurs on axis. An important target diagnostic is a fast camera which measures the dynamics of foil runhyphen;in and implosion symmetry. These measurements are made in the visible, UV, and xhyphen;ray portions of the electromagnetic spectrum. UV/xhyphen;ray images are first converted to visible light, then transmitted by visible light optics to a framing camera, which is located at a safe distance. For UV/soft xhyphen;ray imaging, we mount a disposable pinhole camera with aphyphen;terphenylhyphen;coated converter screen on the target chamber. For soft/hard xhyphen;ray imaging, a microchannel plate is used in front of thephyphen;terphenylhyphen;coated screen to boost quantum detection efficiency and signal gain. For faster temporal response thephyphen;terphenyl can be replaced by NEhyphen;111 or other fast fluors. Image transmission is accomplished by means of two large mirrors (150ndash;250 mm diam) and a large catadioptric telescope. The framing camera consists of four gated microchannel plates with adjustable gate and interframe times. The framing camera is a versatile and rugged instrument, it has performed satisfactorily for each and every Pioneer shot. Experimental data indicate that this camera, which uses individual gated microchannel plates, is far superior to commercial streak/framing cameras, because it has a dynamic range which is orders of magnitude larger than commercial cameras, each channel can be attenuated separately, further increasing the dynamic range of the imaging system. This makes our framing camera especially suitable for recording sequences of events where the brightness changes by many orders of magnitude. This work was performed under the auspices of U.S. DOE.
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