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Experimental investigation of high mach number 3D hydrodynamic jets at the National Ignition Facility

Description: The first hydrodynamics experiments were performed on the National Ignition Facility. A supersonic jet was formed via the interaction of a laser driven shock ({approx}40 Mbars) with 2D and 3D density perturbations. The temporal evolution of the jet's spatial scales and ejected mass were measured with point projection x-ray radiography. Measurements of the large-scale features and mass are in good agreement with 2D and 3D numerical simulations. These experiments are the first quantitative measur… more
Date: September 24, 2004
Creator: Blue, B. E.; Weber, S.; Glendinning, S.; Lanier, N.; Woods, D.; Bono, M. et al.
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Partner: UNT Libraries Government Documents Department
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Analysis of the National Ignition Facility Ignition Hohlraum Energetics Experiments

Description: A series of forty experiments on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] to study energy balance and implosion symmetry in reduced- and full-scale ignition hohlraums was shot at energies up to 1.3 MJ. This paper reports the findings of the analysis of the ensemble of experimental data obtained that has produced an improved model for simulating ignition hohlraums. Last year the first observation in a NIF hohlraum of energy transfer between cones… more
Date: November 22, 2010
Creator: Town, R. J.; Rosen, M. D.; Michel, P. A.; Divol, L.; Moody, J. D.; Kyrala, G. A. et al.
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Partner: UNT Libraries Government Documents Department
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Observations and Modeling of Debris and Shrapnel Impacts on Optics and Diagnostics at the National Ignition Facility

Description: A wide range of targets with laser energies spanning two orders of magnitude have been shot at the National Ignition Facility (NIF). The National Ignition Campaign (NIC) targets are cryogenic with Si supports and cooling rings attached to an Al thermo-mechanical package (TMP) with a thin (30 micron) Au hohlraum inside. Particular attention is placed on the low-energy shots where the TMP is not completely vaporized. In addition to NIC targets, a range of other targets has also been fielded on NI… more
Date: November 4, 2011
Creator: Eder, D.; Bailey, D.; Chamgers, F.; Darnell, I.; Nicola, P. D.; Dixit, S. et al.
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Partner: UNT Libraries Government Documents Department
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A Programmable Beam Shaping System for Tailoring the Profile of High Fluence Laser Beams

Description: Customized spatial light modulators have been designed and fabricated for use as precision beam shaping devices in fusion class laser systems. By inserting this device in a low-fluence relay plane upstream of the amplifier chain, 'blocker' obscurations can be programmed into the beam profile to shadow small isolated flaws on downstream optical components that might otherwise limit the system operating energy. In this two stage system, 1920 x 1080 bitmap images are first imprinted on incoherent,… more
Date: November 10, 2010
Creator: Heebner, J.; Borden, M.; Miller, P.; Stolz, C.; Suratwala, T.; Wegner, P. et al.
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Partner: UNT Libraries Government Documents Department
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The First Experiments on the National Ignition Facility

Description: A first set of laser-plasma interaction, hohlraum energetics and hydrodynamic experiments have been performed using the first 4 beams of the National Ignition Facility (NIF), in support of indirect drive Inertial Confinement Fusion (ICF) and High Energy Density Physics (HEDP). In parallel, a robust set of optical and x-ray spectrometers, interferometer, calorimeters and imagers have been activated. The experiments have been undertaken with laser powers and energies of up to 8 TW and 17 kJ in fl… more
Date: November 11, 2005
Creator: Landen, O. L.; Glenzer, S.; Froula, D.; Dewald, E.; Suter, L. J.; Schneider, M. et al.
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Partner: UNT Libraries Government Documents Department
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A Study of Laser System Requirements for Application in Beam Diagnostics And Polarimetry at the ILC

Description: Advanced laser systems will be essential for a range of diagnostics devices and polarimetry at the ILC. High average power, high beam quality, excellent stability and reliability will be crucial in order to deliver the information required to attain the necessary ILC luminosity as well as for efficient polarimetry. The key parameters are listed together with the R & D required to achieve the necessary laser system performance.
Date: February 12, 2007
Creator: Dixit, S.; Delerue, N.; Foster, B.; Howell, D. F.; Peach, K.; Quelch, G. et al.
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Partner: UNT Libraries Government Documents Department
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3w Transmitted Beam Diagnostic at the Omega Laser Facility

Description: A 3{omega} transmitted beam diagnostic has been commissioned on the Omega Laser at the Laboratory for Laser Energetics, University of Rochester [Soures et.al., Laser Part. Beams 11 (1993)]. Transmitted light from one beam is collected by a large focusing mirror and directed onto a diagnostic platform. The near field of the transmitted light is imaged; the system collects information from twice the original f-cone of the beam. Two gated optical cameras capture the near field image of the transmi… more
Date: April 24, 2006
Creator: Froula, D. H.; Rekow, V.; Sorce, C.; Piston, K.; Knight, R.; Alvarez, S. et al.
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Partner: UNT Libraries Government Documents Department
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High-Power Laser Source Evaluation

Description: Robust Nuclear-Weapons-Effects Testing (NWET) capability will be needed for the foreseeable future to ensure the performance and reliability, in nuclear environments, of the evolving U.S. stockpile of weapons and other assets. Ongoing research on the use of high-energy lasers to generate environments of utility in nuclear weapon radiation effects simulations is addressed in the work described in this report. Laser-driven hohlraums and a variety of other targets have been considered in an effort… more
Date: July 1, 1998
Creator: Back, C. A.; Davis, J. F.; Decker, C. D.; Dixit, S.; Grun, J.; Managan, R. A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Three-Dimensional Hydrodynamics Experiments on the National Ignition Facility

Description: The production of supersonic jets of material via the interaction of a strong shock wave with a spatially localized density perturbation is a common feature of inertial confinement fusion and astrophysics. The behavior of two-dimensional (2D) supersonic jets has previously been investigated in detail [J. M. Foster et. al, Phys. Plasmas 9, 2251 (2002)]. In three-dimensions (3D), however, there are new aspects to the behavior of supersonic jets in compressible media. In this paper, the commission… more
Date: November 12, 2004
Creator: Blue, B. E.; Weber, S. V.; Glendinning, S.; Lanier, N.; Woods, D.; Bono, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Programmable Beam Spatial Shaping System for the National Ignition Facility

Description: A system of customized spatial light modulators has been installed onto the front end of the laser system at the National Ignition Facility (NIF). The devices are capable of shaping the beam profile at a low-fluence relay plane upstream of the amplifier chain. Their primary function is to introduce 'blocker' obscurations at programmed locations within the beam profile. These obscurations are positioned to shadow small, isolated flaws on downstream optical components that might otherwise limit t… more
Date: January 21, 2011
Creator: Heebner, J.; Borden, M.; Miller, P.; Hunter, S.; Christensen, K.; Scanlan, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress in Long Scale Length Laser-Plasma Interactions

Description: The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 mm and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3{omega}) with a total intensity of 2 x 10{sup 15} W cm{sup -2}. The targets were filled with 1 atm of CO{sub 2} producing of up to 7 mm long homogeneous… more
Date: November 11, 2003
Creator: Glenzer, S. H.; Arnold, P.; Bardsley, G.; Berger, R. L.; Bonanno, G.; Borger, T. et al.
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Partner: UNT Libraries Government Documents Department
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Performance of Thin Borosilicate Glass Sheets at 351-nm

Description: Commercial thin borosilicate glass sheets have been evaluated for use as a single-shot optic ''debris shield'' to separate the radiation and contamination produced by the inertial confinement fusion (ICF) experiment from the expensive precision laser optics which focus and shape the 351-nm laser beam which irradiates the target. The goal of this work is identification of low cost materials that can deliver acceptable beam energy and focal spots to the target. The two parameters that dominate th… more
Date: November 1, 2001
Creator: Whitman, P. K.; Staggs, M.; Carr, W.; Dixit, S.; Sell, W. & Milam, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser Coupling to Reduced-Scale Targets at the Early Light Program of the National Ignition Facility

Description: A platform for analysis of material properties under extreme conditions, where a sample is bathed in radiation with a high temperature, is under development. This hot environment is produced with a laser by depositing maximum energy into a small, high-Z can. Such targets were recently included in an experimental campaign using the first four of the 192 beams of the National Ignition Facility, under construction at the University of California Lawrence Livermore National Laboratory. These target… more
Date: November 18, 2004
Creator: Hinkel, D. E.; Schneider, M. B.; Baldis, H. A.; Bower, D.; Campbell, K. M.; Celeste, J. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Shock timing on the National Ignition Facility: First Experiments

Description: An experimental campaign to tune the initial shock compression sequence of capsule implosions on the National Ignition Facility (NIF) was initiated in late 2010. The experiments use a NIF ignition-scale hohlraum and capsule that employs a reentrant cone to provide optical access to the shocks as they propagate in the liquid deuterium-filled capsule interior. The strength and timing of the shock sequence is diagnosed with velocity interferometry that provides target performance data used to set … more
Date: October 24, 2011
Creator: Celliers, P. M.; Robey, H. F.; Boehly, T. R.; Alger, E.; Azevedo, S.; Berzins, L. V. et al.
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Partner: UNT Libraries Government Documents Department
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X-ray flux and x-ray burnthrough experiments on reduced-scale targets at the NIF and OMEGA lasers

Description: An experimental campaign to maximize radiation drive in small-scale hohlraums has been carried out at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (Livermore, CA USA) and at the OMEGA laser at the Laboratory for Laser Energetics (Rochester, NY USA). The small-scale hohlraums, laser energy, laser pulse, and diagnostics were similar at both facilities but the geometries were very different. The NIF experiments used on-axis laser beams whereas the OMEGA experi… more
Date: August 24, 2005
Creator: Schneider, M.; Hinkel, D.; Young, B.; Holder, J.; Langdon, A.; Baldis, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The National Ignition Facility Performance Status

Description: The National Ignition Facility (NIF) laser has been designed to support high energy density science (HEDS), including the demonstration of fusion ignition through Inertial Confinement. NIF operated a single ''quad'' of 4 beams from December 2002 through October 2004 in order to gain laser operations experience, support target experiments, and demonstrate laser performance consistent with NIF's design requirement. During this two-year period, over 400 Main Laser shots were delivered at 1{omega} … more
Date: August 30, 2005
Creator: Haynam, C.; Auerbach, J.; Nicola, J. D.; Dixit, S.; Heestand, G.; Henesian, M. et al.
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Partner: UNT Libraries Government Documents Department
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NIF Final Optics System: Frequency Conversion and Beam Conditioning

Description: Installation and commissioning of the first of forty-eight Final Optics Assemblies on the National Ignition Facility was completed this past year. This activity culminated in the delivery of first light to a target. The final optics design is described and selected results from first-article commissioning and performance tests are presented.
Date: January 28, 2004
Creator: Wegner, P.; Auerbach, J.; Biesiada, T.; Dixit, S.; Lawson, J.; Menapace, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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