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NNSA Perspective on Scientific Opportunities in High Energy Density Laboratory Plasma Physics. Mike Donovan Acting Director, ICF Program. August 25, 2008. Why does NNSA care about HEDLP?. NNSA Interests: Possessing validated predictive nuclear weapons codes Stockpile confidence
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NNSA Perspective on Scientific Opportunities in High Energy Density Laboratory Plasma Physics Mike Donovan Acting Director, ICF Program August 25, 2008
Why does NNSA care about HEDLP? • NNSA Interests: • Possessing validated predictive nuclear weapons codes • Stockpile confidence • Stockpile maintenance costs • Without nuclear explosive tests • Understanding the science to build those codes • Material properties • Shock physics • Equations of State • Transport coefficients • Collective effects in mixing • . . . • High quality scientists in NNSA laboratories for classified and applied weapons work NNSA needs advances in fundamental and applied high energy density science
Why academic and private researchers? • Have an institutional focus on creative discovery science • Are independent of the NNSA methods and conclusions • Live in a world of open, vigorous peer review • Make NNSA laboratory scientists better by competing • Develop the knowledge to provide peer reviews to nuclear weapons scientists Some will become the next generation of lab scientists Lab and non-Lab researchers are complementary
NNSA agrees with HEDSA* positions • Intermediate and small scale facility research provides the greatest benefit at this time • Large facility research could be appealing in a collaborative mode in the future with the maturation of HEDLP • Access to computational hardware and software would assist in the progress of this research • The best proposals should be funded over a broad range of HEDLP topics For academic and private research in the HEDLP Joint Program: *HEDSA: High Energy Density Science Association
Examples of recent HEDLP research that is valuable to NNSA objectives
Precompression of materials extends the phase space that can be explored • The Equation of State of compressed H and He are explored in R. Jeanloz (UCBerkeley) NLUF program • These results are important to understand the interiors of the giant gas planets • NNSA is interested in extending its understanding of materials properties under extreme conditions Diamond Anvil Cell Target Shock compression of He with different initial densities* * J. Eggert, PRL 100, 124503 (2008)
Dynamic properties of shocked crystals are important to NNSA’s mission • M. A. Myers (UCSD) is PI for an NLUF grant to study dynamic materials properties – in collaboration with U.C. Davis, LLNL, Oxford, LANL, LLE
Multiview tomographic diagnostics are being developed on OMEGA • R. Mancini (UNR), with LLNL and LLE, is developing tomographic diagnostics through NLUF • This work promises further understanding of ICF implosions Reconstructed images
Monoenergetic proton radiography – a versatile diagnostic tool for ICF and HED experiments • R. Petrasso et al. (MIT) is developing monoenergetic proton radiography on OMEGA with a NLUF grant Measurements of transient electromagnetic fields on OMEGA Charged particles from nuclear reactions probe the fields in a target
Cornell’s Pulsed-power-drivenHED Laboratory Plasma Studies Center • Mission • Advance understanding of HED plasma physics • Develop new HED diagnostics, e.g., X-ray backlighting, time-gated imaging, magnetic fields • Be available as a user facility • Help develop intense x-ray sources • Investigate novel HED plasma configurations • Train the next generation of HED scientists Cylindrical Wire Arrays Three of 4 X-pinch x-ray backlighter images (from a single wire-array z-pinch pulse), and a current trace with the x-ray signals showing X-pinch timing Radial Wire Array
5ns Efficient X-ray conversion with wire-arrays is being studied on small Z-pinches Results from star-like arrays from the Nevada Terawatt Facility (2 TW Z Pinch) • Star-like arrays produce powerful short x-ray pulses • Implosion in star-like arrays cascades from wire to wire 3-ray star 8-ray star • Star-like arrays have small shot-to-shot variations Star 16 / 12 / 8 / 6 mm, 12 x12µm • Nested quadruple array 0 50 100 150 200 V.V. Ivanov at al., Phys. Rev. Lett. 100, 025004 (2008)
Montgomery LANL CH 697 nm He 600 nm N2 / H2 KEEN waves constitute a new form of plasma self-organization driven by optical mixing and detected on Trident
Summary NNSA needs advances in fundamental and applied high energy density science