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Experimental Studies of ICF Indirect-Drive Be and High Density C Candidate Ablators

Description: To validate our modeling of the macroscopic and microscopic hydrodynamic and equation of state response of these candidate ablators to NIC-relevant x-ray drive, a multi-lab experimental program has been verifying the behavior of these new ablators. First, the pressures for onset and termination of melt for both Be and HDC under single or double shock drive has been measured at the Z and Omega facilities. Second, the level and effect of hard x-ray preheat has been quantified in scaled experiment… more
Date: September 5, 2007
Creator: Landen, O. L.; Bradley, D. K.; Braun, D. G.; Smalyuk, V. A.; Hicks, D. G.; Celliers, P. M. et al.
Partner: UNT Libraries Government Documents Department
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Soft X-ray Imaging

Description: The contents of this report cover the following: (1) design of the soft x-ray telescope; (2) fabrication and characterization of the soft x-ray telescope; and (3) experimental implementation at the OMEGA laser facility.
Date: May 20, 1999
Creator: Seely, John
Partner: UNT Libraries Government Documents Department
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Indirect-Drive Time Dependent Symmetry Diagnosis at NIF-Scale

Description: The scaling to NIF of current techniques used to infer the time-dependent flux asymmetries for indirectly-driven capsules is reviewed. We calculate that the projected accuracy for detecting the lowest mode asymmetries by a variety of techniques now meet the requirements for symmetry tuning for ignition. The scaling to NIF has also motivated the implementation of new, more efficient and hence less perturbative backlighting techniques which have recently provided high quality symmetry data during… more
Date: October 27, 1999
Creator: Landen, O. L.; Bradley, D. K.; Pollaine, S. M.; Amendt, P. A.; Glendinning, S. G.; Suter, L. J. et al.
Partner: UNT Libraries Government Documents Department
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Cryogneic-Target Performance and Implosion Physics Studies on OMEGA

Description: Recent progress in direct-drive cryogenic implosions on the OMEGA Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] is reviewed. Ignition-relevant areal densities of ~200 mg/cm^2 in cryogenic D2 implosions with peak laser-drive intensities of ~5 x 10^14 W/cm^2 were previously reported [T. C. Sangster et al., Phys. Rev. Lett. 100, 185006 (2008)]. The laser intensity is increased to ~10^15 W/cm^2 to demonstrate ignition-relevant implosion velocities of 3–4 x 10^7 cm/ s, providing… more
Date: March 6, 2009
Creator: Smalyuk, V. A.; Betti, R.; Boehly, T. R.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H. et al.
Partner: UNT Libraries Government Documents Department
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Precision Manufacturing of Inertial Confinement Fusion Double Shell Laser Targets for OMEGA

Description: Double shell targets have been built by Lawrence Livermore National Laboratory (LLNL) for inertial confinement fusion (ICF) experiments on the Omega laser at the University of Rochester and as a prelude to similar experiments on NIF. Of particular interest to ICF studies are high-precision double shell implosion targets for demonstrating thermonuclear ignition without the need for cryogenic preparation. Because the ignition tolerance to interface instabilities is rather low, the manufacturing r… more
Date: November 21, 2003
Creator: Amendt, P. A.; Bono, M. J.; Hibbard, R. L.; Castro, C. & Bennett, D. W.
Partner: UNT Libraries Government Documents Department
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Electric field measurements from satellites to forbidden line ratios in an Omega-Upgrade laser-produced plasma. Second semi-annual report, June 1, 1996--November 30, 1996

Description: During this reporting period we conducted experiments both on the Omega Upgrade 60 beam laser at the University of Rochester Laboratory for Laser Energetics (LLE) and on the Trident laser at Los Alamos National Laboratory (LANL). 3 figs.
Date: December 16, 1996
Creator: Griem, H. R.; Elton, R. C. & Welch, B. L.
Partner: UNT Libraries Government Documents Department
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Direct Drive Cylindrical Implosions on the Omega Laser at the Laboratory for Laser Energetics of the University of Rochester

Description: The primary goals of this report are to (1) understand experimental radiography better (radiograph known static targets); and (2) to better understand the sources and effects of short wavelength perturbations on the long wavelength RT growth. Some secondary goals are to initiate Richtmyer-Meshkov mix targets; test beryllium cylinder implosions (if available); and observe emission spectroscopy from chlorinated foam to study implosions. To achieve these goals the authors: (1) shot mix targets wit… more
Date: May 10, 1999
Creator: Barnes, C.W.
Partner: UNT Libraries Government Documents Department
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LLE 1995 annual report, October 1994--September 1995

Description: The fiscal year ending September 1995 (FY95) concluded the third year of the cooperative agreement (DE-FC03-92SF19460) with the U.S. Department of Energy (DOE). This report summarizes research at the Laboratory for Laser Energetics (LLE) and reports on the successful completion of the OMEGA Upgrade. Previous annual reports describe the OMEGA Upgrade design. The preliminary design for the system was complete in October 1989 and the detailed design started in October 1990. The original 24-beam OM… more
Date: January 1, 1996
Partner: UNT Libraries Government Documents Department
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Pinhole aperture point backlighter development experiments on Trident, 9-13, 2001

Description: Pinhole aperture point backlighter (PAPBL) imaging has been used on experiments on Omega, but results have been compromised by large backgrounds. This technique has advantages over traditional area backlighting/pinhole imaging, and the Omega experiments could benefit from this capability, but Omega time is expensive and not the place for developing diagnostic techniques if they can be developed on Trident instead. PAPBL, shot from Direct Drive Cylinder Mix experiments on Omega (DDCYLMIX 00-1, J… more
Date: January 1, 2001
Creator: Lanier, N. E. (Nicholas E.) & Murphy, Thomas J.
Partner: UNT Libraries Government Documents Department
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FABRICATION AND PROPERTIES OF OER COATED RESORCINOL-FORMALDEHYDE SHELLS FOR OMEGA EXPERIMENTS

Description: OAK-B135 New high gain designs for direct drive ignition on NIF require foam shells. Scaled down versions of these designs are needed for near term experiments on the OMEGA laser facility at the Laboratory Laser Energetics (LLE). These shells need to be about 1 mm in diameter and 50-100 {micro}m wall thickness and densities of 100-250 mg/cc. In addition, a full density permeation seal needs to be deposited for retention of the fill gas at room temperature or the ice at cryogenic temperatures. T… more
Date: June 1, 2003
Creator: Nikroo, A.; Czechowicz, D.; Paguio, R.; Greenwood, A. L. & Takagi, M.
Partner: UNT Libraries Government Documents Department
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MECHANICAL PROPERTIES OF THIN GDP SHELLS USED AS CRYOGENIC DIRECT DRIVE TARGETS AT OMEGA

Description: OAK-B135 Thin glow discharge polymer (GDP) shells are currently used as the targets for cryogenic direct drive laser fusion experiments. These shells need to be filled with nearly 1000 atm of D{sub 2} and cooled to cryogenic temperatures without failing due to buckling and bursting pressures they experience in this process. Therefore, the mechanical and permeation properties of these shells are of utmost importance in successful and rapid filling with D{sub 2}. In this paper, they present an ov… more
Date: June 1, 2003
Creator: Nikroo, A.; Czechowicz, D.; Chen, K.C; Dicken, M.; Morris, C.; Andrews, R. et al.
Partner: UNT Libraries Government Documents Department
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Measurements of Wall Stagnation in Gas-Filled ICF Hohlraums

Description: For ICF hohlraums driven by long pulses, such as will be needed for ignition on the NIF, the high-Z wall must be held back to avoid excessive laser spot motion and time-dependent symmetry swings. One means of accomplishing this is to fill the hohlraum with a low density, low-Z gas. We report on gas-wall interface characterization by axial x-ray backlighting and self-emission, on gas filled hohlraums fielded at the Omega facility. Up to 30 drive beams are fired, forming a single ring of illumina… more
Date: August 22, 2003
Creator: Turner, R. E.; Eder, D. C.; Dewald, E. L.; Wallace, R. J.; Amendt, P. A.; Pollaine, S. M. et al.
Partner: UNT Libraries Government Documents Department
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PIN diode array x-ray imaging. Final Technical report

Description: We have completed constructing an x-ray camera based on a solid state imaging device and have obtained images of Omega laser targets. A Si PIN diode array is used. Objective of this project is to investigate the use of a PIN diode array readout device for obtaining images of 1-20 keV x-ray emission from laser targets. The PIN array detector was successfully used for obtaining hard x-ray images in the high powered laser environment and real time images of the x-ray emission from laser targets.
Date: September 1, 1996
Creator: Jernigan, J.G.
Partner: UNT Libraries Government Documents Department
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All Solid State Optical Pulse Shaper for the OMEGA Laser Fusion Facility

Description: OAK-B135 All Solid State Optical Pulse Shaper for the OMEGA Laser Fusion Facility. The authors have developed an all-solid-state, compact, computer-controlled, flexible optical pulse shaper for the OMEGA laser facility. This pulse shaper produces high bandwidth, temporally shaped laser pulses that meet OMEGA requirements. The design is a significant simplification over existing technology with improved performance capabilities.
Date: July 24, 2000
Partner: UNT Libraries Government Documents Department
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Early-time measurements of laser-plasma conditions in omega-upgrade ICF targets. Semi-annual report, October 1, 1997--March 31, 1998

Description: Since arrival of FY-98 funding under this grant in December, we have been preparing for our first series of experiments under this grant at the University of Rochester Laboratory for Laser Energetics (LLE) on the Omega laser facility, now scheduled the week beginning May 4, 1998. We will again be fielding our flat-field, grazing-incidence extreme-ultraviolet (euv) spectrograph with a four-channel gated-stripline microchannel plate (MCP) detector, which is mounted on the outside of the vacuum ch… more
Date: April 4, 1998
Creator: Griem, H. R. & Elton, R. C.
Partner: UNT Libraries Government Documents Department
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A multipurpose TIM-based optical telescope for Omega and the Trident laser facilities

Description: The authors have recently designed and are building a telescope which acts as an imaging light collector relaying the image to an optical table for experiment dependent analysis and recording. The expected primary use of this instrument is a streaked optical pyrometer for witness plate measurements of Hohlraum drive temperature. The telescope is based on University of Rochester`s Ten-Inch Manipulator (TIM) which allows compatibility between Omega, Trident, and the NIF lasers. The optics capture… more
Date: December 31, 1998
Creator: Oertel, J. A.; Murphy, T. J. & Berggren, R. R.
Partner: UNT Libraries Government Documents Department
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LLE 1994 annual report, October 1993--September 1994

Description: This is the 1994 annual report for the University of Rochester, Laboratory for Laser Energetics. The report is presented as a series of research type reports. The titles emphasize the breadth of work carried out. They are: stability analysis of unsteady ablation fronts; characterization of laser-produced plasma density profiles using grid image refractometry; transport and sound waves in plasmas with light and heavy ions; three-halves-harmonic radiation from long-scale-length plasmas revisited;… more
Date: January 1, 1995
Partner: UNT Libraries Government Documents Department
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LLE 1997. Annual report, October 1996--September 1997

Description: The fiscal year ending September 1997 (FY97) concluded the fifth year of the cooperative agreement (DE-FC03-92SF19460) with the U.S. Department of Energy (DOE). This report summarizes research at the Laboratory for Laser Energetics (LLE) and is the final report for the first five years of the cooperative agreement. In September 1997, the cooperative agreement was renewed for an additional five years. We summarize our research during FY97, the operation of the National Laser Users` Facility (NLU… more
Date: January 1, 1998
Partner: UNT Libraries Government Documents Department
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Hohlraum-Driven Ignition-Like Double-Shell Implosion Experiments on Omega: Analysis and Interpretation

Description: An experimental campaign to study hohlraum-driven ignition-like double-shell target performance using the Omega laser facility has begun. These targets are intended to incorporate as many ignition-like properties of the proposed National Ignition Facility (NIF) double-shell ignition design [1,2] as possible, given the energy constraints of the Omega laser. In particular, this latest generation of Omega double-shells is nominally predicted to produce over 99% of the (clean) DD neutron yield from… more
Date: August 22, 2003
Creator: Amendt, P.; Robey, H. F.; Park, H. S.; Tipton, R. E.; Turner, R. E.; Milovich, J. et al.
Partner: UNT Libraries Government Documents Department
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Development of Compton Radiography Diagnostics for Inertial Confinement Fusion Implosions

Description: An important diagnostic tool for inertial confinement fusion will be time-resolved radiographic imaging of the dense cold fuel surrounding the hot spot. The measurement technique is based on point-projection radiography at photon energies from 60-200 keV where the Compton effect is the dominant contributor to the opacity of the fuel or pusher. We have successfully applied this novel Compton Radiography technique to the study of the final compression of directly driven plastic capsules at the OM… more
Date: November 16, 2010
Creator: Tommasini, R.; Hatchett, S. P.; Hey, D. S.; Izumi, N.; Koch, J. A.; Landen, O. L. et al.
Partner: UNT Libraries Government Documents Department
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