140 likes | 279 Views
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
E N D
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