On the transparency of foam in low-density foam Z-pinch experiments
- Prism Computational Sciences, Inc., Madison, WI (United States)
- Sandia National Labs., Albuquerque, NM (United States)
- Los Alamos National Lab., NM (United States)
Foam Z-pinch experiments have been performed on the SATURN and Z machines at Sandia National Laboratories to study physics issues related to x-ray radiation generation and inertial confinement fusion. A significant issue for foam Z-pinch experiments is the transparency of the heated foam as a function of time and wavelength. Foam transparency will be important in future foam Z-pinch experiments both because it influences the time-dependent radiation field seen by an ICF capsule embedded in the foam, and because it is an important factor in making high-resolution spectral measurements of a capsule or tracers embedded in the foam. In this paper, the authors describe results from simulations and experiments which address the issue of foam transparency. They discuss imaging data from one Z experiment in which x-ray emission from a half-Au/half-CH disk located at the bottom of a 1 cm-tall, 14 mg/cc TPX foam is observed. Simulation results predicting CH foam optical depths as a function of plasma conditions are presented. In addition, the authors present results from spectral calculations which utilize 2-D MHD simulation predictions for the time-dependent foam conditions. The results indicate that the observed x-ray framing camera images are consistent with early-time (several ns prior to stagnation) foam electron temperatures of {approx_gt} 30 eV, which is somewhat hotter than the foam electron temperatures predicted from the 2-D MHD simulations at early times.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 307955
- Report Number(s):
- LA-UR-98-2709; CONF-980605-; ON: DE99001667; TRN: 99:003214
- Resource Relation:
- Conference: 12. topical conference on high-temperature plasma diagnostics, Princeton, NJ (United States), 7-11 Jun 1998; Other Information: PBD: [1998]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Amplitude reduction of nonuniformities induced by magnetic Rayleigh-Taylor instabilities in Z-pinch dynamic hohlraums
Amplitude reduction of nonuniformities induced by magnetic Rayleigh Taylor instabilities in z-pinch dynamic hohlraums.