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Title: Streaked extreme ultraviolet imaging of the motion of low-Z foam buffered indirectly driven intermediate and high-Z payloads

Abstract

Results of experiments conducted at the Central Laser Facility (Rutherford Appleton Laboratory), illustrating the efficacy of utilizing a combination of transonic and subsonic ablation to increase the impulse delivered to an indirectly driven payload, are reported. Extreme ultraviolet imaging has been utilized to map the trajectory of the rear surface of an accelerating payload driven by a hohlraum with a peak energy-density-equivalent radiation temperature of around 130 eV. Payloads comprising an approximately 30-{mu}m-thick solid-density plastic foil doped with chlorine, both with and without a gold flashing on the driver-facing surface, were accelerated by a combination of subsonic x-ray ablation of the rear surface of the payload and either subsonic, transonic, or supersonic ablation in a hohlraum facing low-density foam layer in intimate contact with the payload. Two different thicknesses of foam layer were incorporated in the experiment -- 150 and 200 {mu}m -- in addition to a range of different foam densities from 30 to 100 mg/cc. It was observed that the maximum impulse was delivered in the case where the ablation wave propagation was approximately transonic in the foam layer. In such cases the impulse delivered to the payload was significantly greater than that achieved by direct (subsonic) ablationmore » of the payload.« less

Authors:
; ; ; ; ; ; ; ;  [1];  [2];  [2];  [3]
  1. Plasma Physics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London, SW7 2BZ (United Kingdom)
  2. (United Kingdom)
  3. (Germany)
Publication Date:
OSTI Identifier:
20782562
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 3; Other Information: DOI: 10.1063/1.2183749; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABLATION; CHLORINE; DENSITY; DOPED MATERIALS; ELECTRON TEMPERATURE; ENERGY DENSITY; EXTREME ULTRAVIOLET RADIATION; FOAMS; ION TEMPERATURE; LASER-PRODUCED PLASMA; LASERS; LAYERS; LIGHT TRANSMISSION; PLASMA DIAGNOSTICS; PLASMA HEATING; PLASTICS; PULSES; SURFACES; WAVE PROPAGATION; X RADIATION; X-RAY SOURCES

Citation Formats

Pasley, J., Nilson, P., Willingale, L., Haines, M.G., Notley, M., Tolley, M., Neely, D., Nazarov, W., Willi, O., Central Laser Facility, CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, University of St. Andrews, School of Chemistry, St. Andrews, KY16 9AJ, and University of Dusseldorf, Dusseldorf. Streaked extreme ultraviolet imaging of the motion of low-Z foam buffered indirectly driven intermediate and high-Z payloads. United States: N. p., 2006. Web. doi:10.1063/1.2183749.
Pasley, J., Nilson, P., Willingale, L., Haines, M.G., Notley, M., Tolley, M., Neely, D., Nazarov, W., Willi, O., Central Laser Facility, CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, University of St. Andrews, School of Chemistry, St. Andrews, KY16 9AJ, & University of Dusseldorf, Dusseldorf. Streaked extreme ultraviolet imaging of the motion of low-Z foam buffered indirectly driven intermediate and high-Z payloads. United States. doi:10.1063/1.2183749.
Pasley, J., Nilson, P., Willingale, L., Haines, M.G., Notley, M., Tolley, M., Neely, D., Nazarov, W., Willi, O., Central Laser Facility, CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, University of St. Andrews, School of Chemistry, St. Andrews, KY16 9AJ, and University of Dusseldorf, Dusseldorf. Wed . "Streaked extreme ultraviolet imaging of the motion of low-Z foam buffered indirectly driven intermediate and high-Z payloads". United States. doi:10.1063/1.2183749.
@article{osti_20782562,
title = {Streaked extreme ultraviolet imaging of the motion of low-Z foam buffered indirectly driven intermediate and high-Z payloads},
author = {Pasley, J. and Nilson, P. and Willingale, L. and Haines, M.G. and Notley, M. and Tolley, M. and Neely, D. and Nazarov, W. and Willi, O. and Central Laser Facility, CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX and University of St. Andrews, School of Chemistry, St. Andrews, KY16 9AJ and University of Dusseldorf, Dusseldorf},
abstractNote = {Results of experiments conducted at the Central Laser Facility (Rutherford Appleton Laboratory), illustrating the efficacy of utilizing a combination of transonic and subsonic ablation to increase the impulse delivered to an indirectly driven payload, are reported. Extreme ultraviolet imaging has been utilized to map the trajectory of the rear surface of an accelerating payload driven by a hohlraum with a peak energy-density-equivalent radiation temperature of around 130 eV. Payloads comprising an approximately 30-{mu}m-thick solid-density plastic foil doped with chlorine, both with and without a gold flashing on the driver-facing surface, were accelerated by a combination of subsonic x-ray ablation of the rear surface of the payload and either subsonic, transonic, or supersonic ablation in a hohlraum facing low-density foam layer in intimate contact with the payload. Two different thicknesses of foam layer were incorporated in the experiment -- 150 and 200 {mu}m -- in addition to a range of different foam densities from 30 to 100 mg/cc. It was observed that the maximum impulse was delivered in the case where the ablation wave propagation was approximately transonic in the foam layer. In such cases the impulse delivered to the payload was significantly greater than that achieved by direct (subsonic) ablation of the payload.},
doi = {10.1063/1.2183749},
journal = {Physics of Plasmas},
number = 3,
volume = 13,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
  • Low-density plastic foam filled with liquid deuterium is one of the candidates for inertial fusion target. Density profile and trajectory of 527 nm laser-irradiated planer foam-deuterium target in the acceleration phase were observed with streaked side-on x-ray backlighting. An x-ray imager employing twin slits coupled to an x-ray streak camera was used to simultaneously observe three images of the target: self-emission from the target, x-ray backlighter profile, and the backlit target. The experimentally obtained density profile and trajectory were in good agreement with predictions by one-dimensional hydrodynamic simulation code ILESTA-1D.
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