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Design of the target area for the National Ignition Facility

Description: The preliminary design of the target area for the National Ignition Facility has been completed. The target area is required to meet a challenging set of engineering system design requirements and user needs. The target area must provide the appropriate conditions before, during, and after each shot. The repeated introduction of large amounts of laser energy into the chamber and subsequent target emissions represent new design challenges for ICF facility design. Prior to each shot, the target area must provide the required target illumination, target chamber vacuum, diagnostics, and optically stable structures. During the shot, the impact of the target emissions on the target chamber, diagnostics, and optical elements is minimized and the workers and public are protected from excessive prompt radiation doses. After the shot, residual radioactivation is managed to allow the required accessibility. Diagnostic data is retrieved, operations and maintenance activities are conducted, and the facility is ready for the next shot. The target area subsystems include the target chamber, target positioner, structural systems, target diagnostics, environmental systems, and the final optics assembly. The engineering design of the major elements of the target area requires a unique combination of precision engineering, structural analysis, opto-mechanical design, random vibration suppression, thermal stability, materials engineering, robotics, and optical cleanliness. The facility has been designed to conduct both x- ray driven targets and to be converted at a later date for direct drive experiments. The NIF has been configured to provide a wide range of experimental environments for the anticipated user groups of the facility. The design status of the major elements of the target area is described.
Date: January 1, 1997
Creator: Foley, R.J.; Karpenko, V.P. & Adams, C.H.
Partner: UNT Libraries Government Documents Department

Use of Lasers to Study the Impact of Fractionation and Condensation on the Toxicity of Nuclear Weapon Fallout

Description: An experimental concept has been developed to collect data to aid in the refinement of simulation programs designed to predict the fallout effects arising from surface and shallowly buried nuclear weapon detonations. These experiments, called the Condensation Debris Experiments (CDE), are intended to study the condensation/fractionation of material that is liberated following an initial deposition of laser energy onto a small, characterized target. The CDE effort also encompasses target development and material studies as well as supporting computational efforts studying radiation hydrodynamics, computational fluid dynamics, and relevant neutron activation processes (not discussed here).
Date: April 1, 2005
Creator: Vidnovic III, T; Bradley, K S; Debonnel, C S; Dipeso, G; Fournier, K; Karpenko, V P et al.
Partner: UNT Libraries Government Documents Department

The Beam Line X NdFe-steel hybrid wiggler for SSRL

Description: A wiggler magnet with 15 periods, each 12.85 cm long, which achieves 1.40 T at a 2.1 cm gap (2.26T at 0.8 cm) has been designed and is now in fabrication at LBL. This wiggler will be the radiation source of the high intensity synchrotron radiation beam line for the Beam Line X PRT facility at SSRL. The magnet utilizes Neodymium-Iron (NdFe) material and Vanadium Permendur (steel) in the hybrid configuration to achieve simultaneously a high magnetic field and short period. Magnetic field adjustment is with a driven chain and ball screw drive system. The magnetic structure is external to an s.s. vacuum chamber which has thin walls, 0.76 mm thickness, at each pole tip for higher field operation. Magnetic design, construction details and magnetic measurements are presented.
Date: March 10, 1987
Creator: Hoyer, E.; Halbach, K.; Humphries, D.; Marks, S.; Plate, D.; Shuman, D. et al.
Partner: UNT Libraries Government Documents Department

National Ignition Facility system design requirements Laser System SDR002

Description: This System Design Requirement document establishes the performance, design, development, and test requirements for the NIP Laser System. The Laser System generates and delivers high-power optical pulses to the target chamber, and is composed of all optical puke creating and transport elements from Puke Generation through Final Optics as well as the special equipment that supports, energizes and controls them. The Laser System consists of the following WBS elements: 1.3 Laser System 1.4 Beam Transport System 1.6 Optical Components 1.7 Laser Control 1.8.7 Final Optics.
Date: August 20, 1996
Creator: Larson, D.W.; Bowers, J.M.; Bliss, E.S.; Karpenko, V.P. & English, E.
Partner: UNT Libraries Government Documents Department

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

Description: New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs.
Date: August 1, 1987
Creator: Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P. et al.
Partner: UNT Libraries Government Documents Department

Thermal damage study of beryllium windows used as vacuum barriers in synchrotron radiation beamlines

Description: An experimental study to investigate thermal-induced damage to SSRL-designed beryllium foil windows was performed at LLNL's Laser Welding Research Facility. The primary goal of this study was to determine the threshold at which thermal-stress-induced damage occurs in these commonly used vacuum barriers. An Nd:Yag pulsed laser with cylindrical optics and a carefully designed test cell provided a test environment that closely resembles the actual beamline conditions at SSRL. Tests performed on two beryllium window geometries, with different vertical aperture dimensions but equal foil thicknesses of 0.254 mm, resulted in two focused total-power thresholds at which incipient damage was determined. For a beam spot size similar to that of the Beamline-X Wiggler Line, onset of surface damage for a 5-mm by 25-mm aperture window was observed at 170 W after 174,000 laser pulses (1.2-ms pulse at 100 pps). A second window with double the vertical aperture dimension (10 mm by 25 mm) was observed to have surface cracking after 180,000 laser pulses with 85 W impinging its front surface. It failed after approximately 1,000,000 pulses. Another window of the same type (10 mm by 25 mm) received 2,160,000 laser pulses at 74.4 W, and subsequent metallographic sectioning revealed no signs of through-thickness damage. Comparison of windows with equal foil thicknesses and aperture dimensions has effectively identified the heat flux limit for incipient failure. The data show that halving the aperture's vertical dimension allows doubling the total incident power for equivalent onsets of thermal-induced damage.
Date: September 17, 1987
Creator: Holdener, F.R.; Johnson, G.L.; Karpenko, V.P.; Wiggins, R.K.; Cerino, J.A.; Dormiani, M.T. et al.
Partner: UNT Libraries Government Documents Department

Thermal loading considerations for synchrotron radiation mirrors

Description: Grazing incidence mirrors used to focus synchrotron radiation beams through small distant apertures have severe optical requirements. The surface distortion due to heat loading of the first mirror in a bending magnet beam line is of particular concern when a large fraction of the incident beam is absorbed. In this paper we discuss mirror design considerations involved in minimizing the thermal/mechanical loading on vertically deflecting first surface mirrors required for SPEAR synchrotron radiation beam lines. Topics include selection of mirror material and cooling method, the choice of SiC for the substrate, optimization of the thickness, and the design of the mirror holder and cooling mechanism. Results obtained using two-dimensional, finite-element thermal/mechanical distortion analysis are presented for the case of a 6/sup 0/ grazing incidence SiC mirror absorbing up to 260 W at Beam Line VIII on the SPEAR ring. Test descriptions and results are given for the material used to thermally couple this SiC mirror to a water-cooled block. The interface material is limited to applications for which the equivalent normal heat load is less than 20 W/cm/sup 2/.
Date: March 26, 1986
Creator: Holdener, F.R.; Berglin, E.J.; Fuchs, B.A.; Humpal, H.H.; Karpenko, V.P.; Martin, R.W. et al.
Partner: UNT Libraries Government Documents Department

A New 500-kV Ion Source Test Stand for HIF

Description: One of the most challenging aspects of ion beam driven inertial fusion energy is the reliable and efficient generation of low emittance, high current ion beams. The primary ion source requirements include a rise time of order 1-msec, a pulse width of at least 20-msec, a flattop ripple of less than 0.1% and a repetition rate of at least 5-Hz. Naturally, at such a repetition rate, the duty cycle of the source must be greater than 108 pulses. Although these specifications do not appear to exceed the state-of-the-art for pulsed power, considerable effort remains to develop a suitable high current ion source. Therefore, we are constructing a 500-kV test stand specifically for studying various ion source concepts including surface, plasma and metal vapor arc. This paper will describe the test stand design specifications as well as the details of the various subsystems and components.
Date: October 5, 2000
Creator: Sangster, T.C.; Ahle, L.E.; Halaxa, E.F.; Karpenko, V.P.; Oldaker, M. E.; Mitchell, J.W. et al.
Partner: UNT Libraries Government Documents Department

Engineering development for a small-scale recirculator experiment

Description: Lawrence Livermore National Laboratory (LLNL) is evaluating the physics and technology of recirculating induction accelerators for heavy-ion inertial-fusion drivers. As part of this evaluation, the authors are building a small-scale recirculator to demonstrate the concept and to use as a test bed for the development of recirculator technologies. System designs have been completed and components are presently being designed and developed for the small-scale recirculator. This paper discusses results of the design and development activities that are presently being conducted to implement the small-scale recirculator experiments. An, overview of the system design is presented along with a discussion of the implications of this design on the mechanical and electrical hardware. The paper focuses primarily on discussions of the development and design of the half-lattice period hardware and the advanced solid-state modulator.
Date: September 4, 1995
Creator: Newton, M.A.; Deadrick, F.J.; Hanks, R.L.; Hawkins, S.A.; Holm, K.A.; Kirbie, H.C. et al.
Partner: UNT Libraries Government Documents Department

New 500-kV Ion Source Test Strand for HIF

Description: One of the most challenging aspects of ion beam driven inertial fusion energy is the reliable and efficient generation of low emittance, high current ion beams. The primary ion source requirements include a rise time of order 1-{micro}sec, a pulse width of at least 20-{micro}sec, a flattop ripple of less than 0.1% and a repetition rate of at least 5-HZ. Naturally, at such a repetition rate, the duty cycle of the source must be greater than 10{sup 8} pulses. Although these specifications do not appear to exceed the state-of-the-art for pulsed power, considerable effort remains to develop a suitable high current ion source. Therefore, we are constructing a 500-kV test stand specifically for studying various ion source concepts including surface, plasma and metal vapor arc. This paper will describe the test stand design specifications as well as the details of the various subsystems and components.
Date: March 9, 2000
Creator: Sangster, T.C.; Ahle, L.E.; Halaxa, E.F.; Karpenko, V.P.; Oldaker, M.E.; Mitchell, J.W. et al.
Partner: UNT Libraries Government Documents Department

LBNL report of the vetting review of the GRETINA project

Description: GRETINA is a gamma-ray detector array capable of reconstructing the energy and spatial positions of gamma-ray interactions within the germanium crystals. It will be used to study the structure and stability of nuclei under various conditions. The new capabilities provided by gamma-ray tracking will give large gains in sensitivity for a large number of experiments, particularly those aimed at nuclei far from beta stability. A proposal for GRETINA was submitted to DOE in June 2003. It presented the scientific case, the readiness of technical development, the design, the suggested management organizations, and a proposed cost and schedule. The GRETINA proposal received its CD0 approval in August 2003. The CD-1 review will be held on December 3 and 4, 2003, and will be handled by the DOE-N. This report presents the charge to the GRETINA vetting review committee, and the findings, comments and recommendations of this committee. The purpose of this project vetting review was to assure that the GRETINA project is on track to provide DOE and the nuclear physics community with the agreed upon deliverables within the agreed upon budget and schedule. The vetting review committee was asked to cover both technical and management aspects of the GRETINA Project. Reviewers offer expert knowledge in relevant areas and provide recommendations and findings to the project's management team. Upon successful completion, the Laboratory's Integrated Project Management Office (IPMO) will recommend signoff of the project to the Laboratory Directorate. The GRETINA vetting review committee was asked to consider all relevant aspects of the project's management, project execution plan (PEP), technical approach and status, cost estimate, resources, schedule and risk and, in doing so, to advise as to whether the GRETINA Project was likely to successfully provide the agreed upon deliverables within the agreed upon budget and schedule. The review committee was asked ...
Date: March 29, 2004
Creator: Robinson, K.E.; Bercovitz, J.H.; Bieser, F.S.; Jared, R.C.; Karpenko, V.P.; Klein, S.R. et al.
Partner: UNT Libraries Government Documents Department

Planning for an integrated research experiment

Description: We describe the goals and research program leading to the Heavy Ion Integrated Research Experiment (IRE). We review the basic constraints which lead to a design and give examples of parameters and capabilities of an IRE. We also show design tradeoffs generated by the systems code IBEAM.
Date: March 25, 2001
Creator: Barnard, J.J.; Ahle, L.E.; Bangerter, R.O.; Bieniosek, F.M.; Celata, C.M.; Faltens, A. et al.
Partner: UNT Libraries Government Documents Department

Planning for an Integrated Research Experiment

Description: The authors describe the goals and research program leading to the Heavy Ion Integrated Research Experiment (IRE). They review the basic constraints which lead to a design and give examples of parameters and capabilities of an IRE. We also show design tradeoffs generated by the systems code IBEAM. A multi-pronged Phase 1 research effort is laying the groundwork for the Integrated Research Experiment. Experiment, technology development, theory, simulation, and systems studies are all playing major roles in this Phase I research. The key research areas are: (1) Source and injector (for investigation of a high brightness, multiple beam, low cost injector); (2) High current transport (to examine effects at full driver-scale line charge density, including the maximization of the beam filling-factor and control of electrons); (3) Enabling technology development (low cost and high performance magnetic core material, superconducting magnetic quadrupole arrays, insulators, and pulsers); and (4) Beam simulations and theory (for investigations of beam matching, specification of accelerator errors, studies of emittance growth, halo, and bunch compression, in the accelerator, and neutralization methods, stripping effects, spot size minimization in the chamber); and (5) Systems optimization (minimization of cost and maximization of pulse energy and beam intensity). They have begun the process of designing, simulating, and optimizing the next major heavy-ion induction accelerator, the IRE. This accelerator facility will, in turn, help provide the basis to proceed to the next step in the development of IFE as an attractive source of fusion energy.
Date: September 15, 2000
Creator: Barnard, J.J.; Ahle, L.E.; Bangerter, R.O.; Bieniosek, F.M.; Celata, C.M.; Faltens, A. et al.
Partner: UNT Libraries Government Documents Department

Progress in heavy ion drivers inertial fusion energy: From scaled experiments to the integrated research experiment

Description: The promise of inertial fusion energy driven by heavy ion beams requires the development of accelerators that produce ion currents ({approx}100's Amperes/beam) and ion energies ({approx}1-10 GeV) that have not been achieved simultaneously in any existing accelerator. The high currents imply high generalized perveances, large tune depressions, and high space charge potentials of the beam center relative to the beam pipe. Many of the scientific issues associated with ion beams of high perveance and large tune depression have been addressed over the last two decades on scaled experiments at Lawrence Berkeley and Lawrence Livermore National Laboratories, the University of Maryland, and elsewhere. The additional requirement of high space charge potential (or equivalently high line charge density) gives rise to effects (particularly the role of electrons in beam transport) which must be understood before proceeding to a large scale accelerator. The first phase of a new series of experiments in Heavy Ion Fusion Virtual National Laboratory (HIF VNL), the High Current Experiments (HCX), is now being constructed at LBNL. The mission of the HCX will be to transport beams with driver line charge density so as to investigate the physics of this regime, including constraints on the maximum radial filling factor of the beam through the pipe. This factor is important for determining both cost and reliability of a driver scale accelerator. The HCX will provide data for design of the next steps in the sequence of experiments leading to an inertial fusion energy power plant. The focus of the program after the HCX will be on integration of all of the manipulations required for a driver. In the near term following HCX, an Integrated Beam Experiment (IBX) of the same general scale as the HCX is envisioned. The step which bridges the gap between the IBX and an engineering test ...
Date: March 1, 2001
Creator: Barnard, J.J.; Ahle, L.E.; Baca, D.; Bangerter, R.O.; Bieniosek, F.M.; Celata, C.M. et al.
Partner: UNT Libraries Government Documents Department

Progress in heavy ion driven inertial fusion energy: From scaledexperiments to the integrated research experiment

Description: The promise of inertial fusion energy driven by heavy ion beams requires the development of accelerators that produce ion currents ({approx}100s Amperesheam) and ion energies ({approx}1-10 GeV) that have not been achieved simultaneously in any existing accelerator. The high currents imply high generalized perveances, large tune depressions. and high space charge potentials of the beam center relative to the beam pipe. Many of the scientific issues associated with ion beams of high perveance and large tune depression have been addressed over the last two decades on scaled experiments at Lawrence Berkeley and Lawrence Livermore National Laboratories, the University of Maryland, and elsewhere. The additional requirement of high space charge potential (or equivalently high line charge density) gives rise to effects (particularly the role of electrons in beam transport) which must be understood before proceeding to a large scale accelerator. The first phase of a new series of experiments in Heavy Ion Fusion Virtual National Laboratory (HIF VNL), the High Current Experiments (HCX), is now being constructed at LBNL. The mission of the HCX will be to transport beams with driver line charge density so as to investigate the physics of this regime, including constraints on the maximum radial filling factor of the beam through the pipe. This factor is important for determining both cost and reliability of a driver scale accelerator. The HCX will provide data for design of the next steps in the sequence of experiments leading to an inertial Fusion energy power plant. The focus of the program after the HCX will be on integration of all of the manipulations required for a driver. In the near term following HCX, an Integrated Beam Experiment (IBX) of the same general scale as the HCX is envisioned.
Date: June 22, 2001
Creator: Barnard, J.J.; Ahle, L.E.; Baca, D.; Bangerter, R.O.; Bieniosek,F.M.; Celata, C.M. et al.
Partner: UNT Libraries Government Documents Department