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Nevada Terawatt Facility College of Science University of Nevada, Reno HEDLP FESAC Subpanel Workshop August, 2008 Nevada Terawatt Facility, University of Nevada Reno Joseph M. Kindel Nevada Terawatt Facility College of Science University of Nevada, Reno Outline • Issues for HEDLP Subpanel • Nevada Terawatt Facility • HEDLP Science at the Nevada Terawatt Facility (NTF) • Conclusions Nevada Terawatt Facility College of Science University of Nevada, Reno Some HEDLP Issues: Small Facilities such as The Nevada Terawatt Facility impact several HEDLP focus areas -As a Staging Facility for the Testing of Novel Physics Ideas and New Diagnostics -Fusion especially in Pinches -Fast Ignition e.g. absorption and transport -The Evolution of Compressible Nonlinear Flows into Turbulence -Plasmas with Embedded Magnetic Fields -The Underlying Physics of High-β Plasmas - Experimental Testbed for Validation of Complex Codes Nevada Terawatt Facility College of Science University of Nevada, Reno Facilities • Zebra 2TW, 100ns pulsed power z pinch • Leopard 50TW, 350fs short pulse laser • Cheetah 10TW, 30fs, 10Hz short pulse laser • Computer Cluster 86 nodes 18.6 TBytes Nevada Terawatt Facility College of Science University of Nevada, Reno 2007: 390 shots on Zebra Nevada Terawatt Facility College of Science University of Nevada, Reno Science at the Nevada Terawatt Facility • Wire array experiments • Planar arrays • The mystery of enhanced x-ray emission • Flute instability and its possible role in changing energy composition • Star-like wire arrays • Laser z-pinch experiments • Magnetized isochoric heating to create extreme conditions of matter • Astrophysical jet formation •Material research Nevada Terawatt Facility College of Science University of Nevada, Reno Planar array Nested quadruple array V. Kantsyrev V. Ivanov Nested quadruple, 24wires, Ø16/12/8/6mm Nevada Terawatt Facility College of Science University of Nevada, Reno Current in the wire array ~ 1 MA z Precursor Wires r Plasma parameters in a precursor plasma 2.0x1019 cm-3, 2.0x1018 noe = noi = Ti~Te = 100eV, Bo = 0.3MG cm-3, b=0.55 WcAl = 1.1x1010s-1 WpAl = 1.4x1013 s-1 Bo(r) jz Nevada Terawatt Facility College of Science University of Nevada, Reno Numerical results Density in linear stage Wi t 0 Wi t 1400 Density in nonlinear stage Wi t 4600 Formation of zonal flow on the nonlinear stage 2D density spectrum 2D density spectrum at the early atkthe linear stage nonlinear stage 30 ky y 150 row row 20 100 10 50 0 0 0 50 50 100 col 150 100 150 200 log_spec_denskxky_1004_t iff 0 kx 10 20 30 col 250 -17.5 -15.0 -12.5 -10.0 -7.5 -5.0 log_spec_denskxky_1014_xy_0 kx -2.5 2D density spectrum at the late nonlinear stage ky 30 row 20 10 0 0 10 20 30 col -20 -15 -10 -5 log_spec_denskxky_1024_xy_0 kx Spectral cascade to short scales Evolution of the density spectrum (kx) in time spec.denskx.1004 1 dens(kx) 1004 dens(kx) 1014 dens(kx) 1024 dens(kx) 1004 0.01 0.0001 10-6 10-8 kx 10-10 1 10 100 1000 kx Evolution of the potential spectrum (kx) in time spec.potkx.1004 pot(kx ) 1004 pot(kx ) 1014 pot(kx ) 1024 100 1 pot(kx) 1004 0.01 0.0001 10-6 10-8 10-10 1 10 100 kx kx 1000 Nevada Terawatt Facility College of Science University of Nevada, Reno Instability of flute modes in a precursor z-pinch plasma can explain experimentally observed properties of excited perturbations • Characteristic wavelengths of excited waves ~ 0.1 - 1 mm • Typical rise time of excited waves ~ 20 ns • Development of large scale cells on nonlinear stage • Wave spectrum cascading towards short scales Axis Axis 2 mm a b Sotnikov, Ivanov et al., IEEE TPS, 2005; Sotnikov, Ivanov et al., CiCP 2008, to be published Nevada Terawatt Facility Leopard Zebra experiment: collimated plasma flow across a magnetic field College of Science University of Nevada, Reno Leopard laser parameters: 60 T Bө I = 1 MA EL ≤ 15 J tFWHM ≈ 350 fs Ф ≥ 50 µm Laser Plasma R. Presura Nevada Terawatt Facility College of Science University of Nevada, Reno Summary • Mature Z-Pinch Facility Ready to Become a User Facility • One Micron Sub-Picosecond 50 TW Laser being Coupled to 2 TW Z-Pinch Small Facilities such as NTF Impact Several HEDLP Focus Areas - As a Staging Facility for the Testing of Novel Physics Ideas and New Diagnostics -Fusion Especially in Pinches -Fast Ignition e.g. absorption and transport - Evolution of Compressible Nonlinear Flows into Turbulence - Plasmas with Embedded Magnetic Fields - Study of Underlying Physics in High-β Plasmas - Experimental Testbed for Validation of Complex Codes