Measurement of the total collisional ionization rates of Ne VI, VII and VIII

Abstract

Abstract.The total collisional ionization rates of neon VI, 1/11 and VIII have been measured in a time-evolving theta-pinch plasma. The method used was to calculate the expected emission from our plasma using the measured time-and space-dependent electron density (10'6-10" cm-3 ) and temperature (120400 eV). The semi-empirical ionization rates of Kunze and Lotz were used in our calculation and were adjusted, by multiplying with a constant, so that the predicted photon emission matched the observed line emission. The multiplicative factors, with estimated errors, required for best fit are: for neon VI, 0.15 0.2; and for neon VIII. 0.7 + 0.25. Also, a comparison is made between the semi-empirical rates used in this work and the recently calculated rates of Summers. These recently calculated rates were in good agreement with our experiment for neon VII and VIII. For neon VI, however, the departure from our experimental result was even farther than for the semi-empirical rate. 0.1: for neon VI]; 0.4

Temperature diagnostics using lithium-like satellites

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Investigation of femtosecond collisional ionization rates in a solid-density aluminium plasma

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Low-energy x-ray emission from magnetic-fusion plasmas

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