We report on the application of well-balanced Ross-filter systems for the diagnostics of x-ray emission from a Z-pinch plasma. The composition and thicknesses of the filter layers were so selected to yield the intensities of neon Hand He-like emission lines separately with relatively good accuracy. The systems provide convenient absolute and time-dependent measurements of the emission intensities, and they are particularly useful for relatively low source-light intensities. The applicability of the systems is examined with the aid of time-dependent modeling of the stagnating plasma, using collisional-radiative and radiation transport calculations. The data and modeling are used to yield information on time evolution of the plasma density and temperature at stagnation.
Experiments have been conducted at Sandia National Laboratories' RITS-6 accelerator facility (operating at 7.5 MV and 180 kA) investigating plasma formation and propagation in relativistic electron beam diodes used for flash x-ray radiography. High resolution, visible and ultraviolet spectra were collected in the A-K gap of the Self-Magnetic Pinch (SMP) diode 1 . Time and space resolved spectra are compared with time-dependent, collisional-radiative (CR) calculations and Lsp, hybrid particle-in-cell code simulations. Results indicate the presence of a dense (1x10 17 cm -3 ), low temperature (few eV), on-axis plasma, composed primarily of protons from electrode surface contaminants, which rapidly expands (10-30cm/μs) from the anode to the cathode. In addition, a cathode plasma sheath is observed which extends several millimeters into the A-K gap. It is believed that the interaction of these electrode plasmas causes a premature impedance collapse of the diode and subsequent reduction in radiation output.Diagnostics include high speed imaging and spectroscopy using nanosecond gated ICCD cameras, streak cameras, and photodiode arrays.1.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.