X-Ray Imaging Measurements of Capsule Implosions Driven by aZ-Pinch Dynamic Hohlraum

Abstract

The radiation and shock generated by impact of an annular tungsten Z-pinch plasma on a 10-mm diam 5-mg/cc CH(2) foam are diagnosed with x-ray imaging and power measurements. The radiative shock was virtually unaffected by Z-pinch plasma instabilities. The 5-ns-duration approximately 135-eV radiation field imploded a 2.1-mm-diam CH capsule. The measured radiation temperature, shock radius, and capsule radius agreed well with computer simulations, indicating understanding of the main features of a Z-pinch dynamic-hohlraum-driven capsule implosion.

Soft X-ray laser diagnostics of exploding aluminum wire plasmas

“…The dynamics of thin exploding metal wire plasmas is of significant interest for the efficient generation of incoherent X-ray pulses of extremely high energy [10][11][12]. Fast Z-pinch implosions of cylindrical wire arrays have been shown to generate high energy density plasmas that emit very intense bursts of incoherent X-ray radiation capable of driving inertial confinement fusion targets [11].…”

“…Extremely compact capillary discharge soft-X-ray lasers [8,9], which are portable and have spectral brightness similar to or higher than that of their laboratory-size predecessors, produce laser pulses of about 1 ns duration that are particularly well suited for the diagnostics of dense pulse-power driven plasmas. Herein we report the results of the study of the evolution of current-induced u Fax: +1-970/491-8671, E-mail: rocca@engr.colostate.edu explosions of thin wires using a capillary discharge 46.9 nm laser in combination with a Mach-Zehnder interferometer in which diffraction gratings are used as beam splitters.The dynamics of thin exploding metal wire plasmas is of significant interest for the efficient generation of incoherent X-ray pulses of extremely high energy [10][11][12]. Fast Z-pinch implosions of cylindrical wire arrays have been shown to generate high energy density plasmas that emit very intense bursts of incoherent X-ray radiation capable of driving inertial confinement fusion targets [11].…”

Diagnostics development plan for ZR.

“…Example applications include x-ray imaging and microscopy of ICF targets in z-pinch-driven hohlraums (ZPDH) [9][10][11] and dynamic hohlraums (DH) [12,13], backlighting of radiation-driven and magnetically-driven experiments, and spectroscopy. ZBL was designed to produce > 2 kJ of 2ω energy in up to four pulses of < 2 ns total duration in a 20 ns interval.…”

“…Possible diagnostic applications for ZBL on ZR include: (1) High-spatial-resolution PP radiography backlighting (25-50 µm resolution) or BCI radiography (5-10 µm resolution) of ICF implosion capsules in ZPDH [9][10][11] and DH [12,13] configurations. A side-on backlighting capability with the monochromatic BCI technique may be important for the DH configuration to measure polar symmetry of pellet implosions in secondary hohlraums where spherical convergence is not present.…”

Shock compression of hydrocarbon polymer foam using molecular dynamics

“…Polymer foam is a crucial part of the dynamic hohlraum platform used to generate intense x-ray radiation at Sandia's Z-machine [1,2,3] and designs for Inertial Confined Fusion (ICF) often involve foams. As experimental designs are being refined -primarily as a result of an interplay between radiation-hydrodynamics modeling, improved diagnostics, and improved drivers -the importance of having accurate material models based on a fundamental understanding of the material's behavior is becoming increasingly clear.…”