Time-resolved optical spectroscopy measurements of pre-pulse plasma formation on Z
The compression of annular wire arrays in z-pinch experiments produces large radiation pulses which are useful for high energy density research. The initial transformation of the wire array into a plasma shell impacts the subsequent implosion of the shell because it affects the current distribution, possibly seeding instabilities. On the Z accelerator the initial plasma is created when a {approximately}300 kA prepulse current flows through the 240--300 wire array during a {approximately}50 nsec period prior to the arrival of the main power pulse, approximately 100 nsec prior to the pinch. Ideally, the authors would like to measure the pre-pulse plasma density and temperature with nsec time resolution and sub {approximately}100 micron two-dimensional spatial resolution. Such measurements are difficult at large accelerators, such as Z, because of limited line of sight access and low experiment rates. Nevertheless, the unique conditions produced on Z discharges imply that it is important to measure the plasma formation characteristics on Z. The strategy is to perform an initial set of limited measurements at Z and interpret the results with the aid of models based on more detailed bench top experiments performed elsewhere. Subsequent more-detailed measurements at Z can then be pursued. The principle diagnostic for the pre-pulse plasma is time-resolved optical spectroscopy.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (US)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 20067646
- Resource Relation:
- Conference: 1999 IEEE International Conference on Plasma Science, Monterey, CA (US), 06/20/1999--06/24/1999; Other Information: PBD: 1999; Related Information: In: The 26th IEEE international conference on plasma science, 342 pages.
- Country of Publication:
- United States
- Language:
- English
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