Axial and temporal gradients in Mo wire array Z pinches
- Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)
Three nested molybdenum wire arrays with initial outer diameters of 45, 50, and 55 mm were imploded by the {approx}20 MA, 90 ns rise-time current pulse of Sandia's Z accelerator. The implosions generated Mo plasmas with {approx_equal}10% of the array's initial mass reaching Ne-like and nearby ionization stages. These ions emitted 2-4 keV L-shell x rays with radiative powers approaching 10 TW. Mo L-shell spectra with axial and temporal resolution were captured and have been analyzed using a collisional-radiative model. The measured spectra indicate significant axial variation in the electron density, which increases from a few times 10{sup 20} cm{sup -3} at the cathode up to {approx}3x10{sup 21} cm{sup -3} near the middle of the 20 mm plasma column (8 mm from the anode). Time-resolved spectra indicate that the peak electron density is reached before the peak of the L-shell emission and decreases with time, while the electron temperature remains within 10% of 1.7 keV over the 20-30 ns L-shell radiation pulse. Finally, while the total yield, peak total power, and peak L-shell power all tended to decrease with increasing initial wire array diameters, the L-shell yield and the average plasma conditions varied little with the initial wire array diameter.
- OSTI ID:
- 20698380
- Journal Information:
- Physics of Plasmas, Vol. 12, Issue 3; Other Information: DOI: 10.1063/1.1840666; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Axial and temporal gradients in Mo wire array Z pinches.
Theoretical z-pinch scaling relations for thermonuclear-fusion experiments