WorldWideScience

Sample records for national magnetic fusion

  1. A National Collaboratory to Advance the Science of High Temperature Plasma Physics for Magnetic Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Schissel, David P. [Princeton Plasma Physics Lab., NJ (United States); Abla, G. [Princeton Plasma Physics Lab., NJ (United States); Burruss, J. R. [Princeton Plasma Physics Lab., NJ (United States); Feibush, E. [Princeton Plasma Physics Lab., NJ (United States); Fredian, T. W. [Massachusetts Institute of Technology, Cambridge, MA (United States); Goode, M. M. [Lawrence Berkeley National Lab., CA (United States); Greenwald, M. J. [Massachusetts Institute of Technology, Cambridge, MA (United States); Keahey, K. [Argonne National Lab., IL (United States); Leggett, T. [Argonne National Lab., IL (United States); Li, K. [Princeton Univ., NJ (United States); McCune, D. C. [Princeton Plasma Physics Lab., NJ (United States); Papka, M. E. [Argonne National Lab., IL (United States); Randerson, L. [Princeton Plasma Physics Lab., NJ (United States); Sanderson, A. [Univ. of Utah, Salt Lake City, UT (United States); Stillerman, J. [Massachusetts Institute of Technology, Cambridge, MA (United States); Thompson, M. R. [Lawrence Berkeley National Lab., CA (United States); Uram, T. [Argonne National Lab., IL (United States); Wallace, G. [Princeton Univ., NJ (United States)

    2012-12-20

    This report summarizes the work of the National Fusion Collaboratory (NFC) Project to develop a persistent infrastructure to enable scientific collaboration for magnetic fusion research. The original objective of the NFC project was to develop and deploy a national FES Grid (FusionGrid) that would be a system for secure sharing of computation, visualization, and data resources over the Internet. The goal of FusionGrid was to allow scientists at remote sites to participate as fully in experiments and computational activities as if they were working on site thereby creating a unified virtual organization of the geographically dispersed U.S. fusion community. The vision for FusionGrid was that experimental and simulation data, computer codes, analysis routines, visualization tools, and remote collaboration tools are to be thought of as network services. In this model, an application service provider (ASP provides and maintains software resources as well as the necessary hardware resources. The project would create a robust, user-friendly collaborative software environment and make it available to the US FES community. This Grid's resources would be protected by a shared security infrastructure including strong authentication to identify users and authorization to allow stakeholders to control their own resources. In this environment, access to services is stressed rather than data or software portability.

  2. A NATIONAL COLLABORATORY TO ADVANCE THE SCIENCE OF HIGH TEMPERATURE PLASMA PHYSICS FOR MAGNETIC FUSION

    Energy Technology Data Exchange (ETDEWEB)

    Allen R. Sanderson; Christopher R. Johnson

    2006-08-01

    This report summarizes the work of the University of Utah, which was a member of the National Fusion Collaboratory (NFC) Project funded by the United States Department of Energy (DOE) under the Scientific Discovery through Advanced Computing Program (SciDAC) to develop a persistent infrastructure to enable scientific collaboration for magnetic fusion research. A five year project that was initiated in 2001, it the NFC built on the past collaborative work performed within the U.S. fusion community and added the component of computer science research done with the USDOE Office of Science, Office of Advanced Scientific Computer Research. The project was itself a collaboration, itself uniting fusion scientists from General Atomics, MIT, and PPPL and computer scientists from ANL, LBNL, and Princeton University, and the University of Utah to form a coordinated team. The group leveraged existing computer science technology where possible and extended or created new capabilities where required. The complete finial report is attached as an addendum. The In the collaboration, the primary technical responsibility of the University of Utah in the collaboration was to develop and deploy an advanced scientific visualization service. To achieve this goal, the SCIRun Problem Solving Environment (PSE) is used on FusionGrid for an advanced scientific visualization service. SCIRun is open source software that gives the user the ability to create complex 3D visualizations and 2D graphics. This capability allows for the exploration of complex simulation results and the comparison of simulation and experimental data. SCIRun on FusionGrid gives the scientist a no-license-cost visualization capability that rivals present day commercial visualization packages. To accelerate the usage of SCIRun within the fusion community, a stand-alone application built on top of SCIRun was developed and deployed. This application, FusionViewer, allows users who are unfamiliar with SCIRun to quickly create

  3. Magnetic fusion technology

    CERN Document Server

    Dolan, Thomas J

    2014-01-01

    Magnetic Fusion Technology describes the technologies that are required for successful development of nuclear fusion power plants using strong magnetic fields. These technologies include: ? magnet systems, ? plasma heating systems, ? control systems, ? energy conversion systems, ? advanced materials development, ? vacuum systems, ? cryogenic systems, ? plasma diagnostics, ? safety systems, and ? power plant design studies. Magnetic Fusion Technology will be useful to students and to specialists working in energy research.

  4. Magnetic-confinement fusion

    Science.gov (United States)

    Ongena, J.; Koch, R.; Wolf, R.; Zohm, H.

    2016-05-01

    Our modern society requires environmentally friendly solutions for energy production. Energy can be released not only from the fission of heavy nuclei but also from the fusion of light nuclei. Nuclear fusion is an important option for a clean and safe solution for our long-term energy needs. The extremely high temperatures required for the fusion reaction are routinely realized in several magnetic-fusion machines. Since the early 1990s, up to 16 MW of fusion power has been released in pulses of a few seconds, corresponding to a power multiplication close to break-even. Our understanding of the very complex behaviour of a magnetized plasma at temperatures between 150 and 200 million °C surrounded by cold walls has also advanced substantially. This steady progress has resulted in the construction of ITER, a fusion device with a planned fusion power output of 500 MW in pulses of 400 s. ITER should provide answers to remaining important questions on the integration of physics and technology, through a full-size demonstration of a tenfold power multiplication, and on nuclear safety aspects. Here we review the basic physics underlying magnetic fusion: past achievements, present efforts and the prospects for future production of electrical energy. We also discuss questions related to the safety, waste management and decommissioning of a future fusion power plant.

  5. Magnetic fusion; La fusion magnetique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document is a detailed lecture on thermonuclear fusion. The basic physics principles are recalled and the technological choices that have led to tokamaks or stellarators are exposed. Different aspects concerning thermonuclear reactors such as safety, economy and feasibility are discussed. Tore-supra is described in details as well as the ITER project.

  6. Magnetic fusion reactor economics

    Energy Technology Data Exchange (ETDEWEB)

    Krakowski, R.A.

    1995-12-01

    An almost primordial trend in the conversion and use of energy is an increased complexity and cost of conversion systems designed to utilize cheaper and more-abundant fuels; this trend is exemplified by the progression fossil fission {yields} fusion. The present projections of the latter indicate that capital costs of the fusion ``burner`` far exceed any commensurate savings associated with the cheapest and most-abundant of fuels. These projections suggest competitive fusion power only if internal costs associate with the use of fossil or fission fuels emerge to make them either uneconomic, unacceptable, or both with respect to expensive fusion systems. This ``implementation-by-default`` plan for fusion is re-examined by identifying in general terms fusion power-plant embodiments that might compete favorably under conditions where internal costs (both economic and environmental) of fossil and/or fission are not as great as is needed to justify the contemporary vision for fusion power. Competitive fusion power in this context will require a significant broadening of an overly focused program to explore the physics and simbiotic technologies leading to more compact, simplified, and efficient plasma-confinement configurations that reside at the heart of an attractive fusion power plant.

  7. Guide to making time-lapse graphics using the facilities of the National Magnetic Fusion Energy Computing Center

    Energy Technology Data Exchange (ETDEWEB)

    Munro, J.K. Jr.

    1980-05-01

    The advent of large, fast computers has opened the way to modeling more complex physical processes and to handling very large quantities of experimental data. The amount of information that can be processed in a short period of time is so great that use of graphical displays assumes greater importance as a means of displaying this information. Information from dynamical processes can be displayed conveniently by use of animated graphics. This guide presents the basic techniques for generating black and white animated graphics, with consideration of aesthetic, mechanical, and computational problems. The guide is intended for use by someone who wants to make movies on the National Magnetic Fusion Energy Computing Center (NMFECC) CDC-7600. Problems encountered by a geographically remote user are given particular attention. Detailed information is given that will allow a remote user to do some file checking and diagnosis before giving graphics files to the system for processing into film in order to spot problems without having to wait for film to be delivered. Source listings of some useful software are given in appendices along with descriptions of how to use it. 3 figures, 5 tables.

  8. Magnetic fusion 1985: what next

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, T.K.

    1985-03-01

    Recent budget reductions for magnetic fusion have led to a re-examination of program schedules and objectives. Faced with delays and postponement of major facilities as previously planned, some have called for a near-term focus on science, others have stressed technology. This talk will suggest a different focus as the keynote for this conference, namely, the applications of fusion. There is no doubt that plasma science is by now mature and fusion technology is at the forefront. This has and will continue to benefit many fields of endeavor, both in actual new discoveries and techniques and in attracting and training scientists and engineers who move on to make significant contributions in science, defense and industry. Nonetheless, however superb the science or how challenging the technology, these are means, not ends. To maintain its support, the magnetic fusion program must also offer the promise of power reactors that could be competitive in the future. At this conference, several new reactor designs will be described that claim to be smaller and economically competitive with fission reactors while retaining the environmental and safety characteristics that are the hallmark of fusion. The American Nuclear Society is an appropriate forum in which to examine these new designs critically, and to stimulate better ideas and improvements. As a preview, this talk will include brief discussions of new tokamak, tandem mirror and reversed field pinch reactor designs to be presented in later sessions. Finally, as a preview of the session on fusion breeders, the talk will explore once again the economic implications of a new nuclear age, beginning with improved fission reactors fueled by fusion breeders, then ultimately evolving to reactors based solely on fusion.

  9. Magnetic fusion: progress -> stagnation -> degradation

    Science.gov (United States)

    Zakharov, Leonid

    2012-10-01

    ``The theory of the failure of magnetic fusion,'' created in 2004 and presented to APS-2007 introduced the notion of the ``difficult'' and ``complicated'' stages of the program and described them details. At the first phase the emerging fusion science was created under strong leadership. Progress was visible on year to year basis, and the program was easy to manage. The complicated phase started in the late 1980s, when the plasma physics appeared to be incapable to implement the mission of ITER to test nuclear components of a fusion reactor. Then, the failure of TFTR (PPPL, USA) and JET (Culham, UK) in the mid 1990 to demonstrate QDT=1 and the blindness of their leaders to already visible means to resolve the problem, were a clear indication of an irreversible stagnation. In fact, right after 2007, it became clear that in the case of a large system of human ``particles'' (scientists) two phases have a continuation. The internal degrees of freedom, otherwise protected from external perturbations by a strong dedication to the scientific method, are now eroding and collapsing. The loss of science in addressing confinement, stability, power extraction, fueling, stationary regimes issues makes the current program irrelevant to fusion energy. A fresh approach should be taken.

  10. SciDAC Fusiongrid Project--A National Collaboratory to Advance the Science of High Temperature Plasma Physics for Magnetic Fusion

    Energy Technology Data Exchange (ETDEWEB)

    SCHISSEL, D.P.; ABLA, G.; BURRUSS, J.R.; FEIBUSH, E.; FREDIAN, T.W.; GOODE, M.M.; GREENWALD, M.J.; KEAHEY, K.; LEGGETT, T.; LI, K.; McCUNE, D.C.; PAPKA, M.E.; RANDERSON, L.; SANDERSON, A.; STILLERMAN, J.; THOMPSON, M.R.; URAM, T.; WALLACE, G.

    2006-08-31

    This report summarizes the work of the National Fusion Collaboratory (NFC) Project funded by the United States Department of Energy (DOE) under the Scientific Discovery through Advanced Computing Program (SciDAC) to develop a persistent infrastructure to enable scientific collaboration for magnetic fusion research. A five year project that was initiated in 2001, it built on the past collaborative work performed within the U.S. fusion community and added the component of computer science research done with the USDOE Office of Science, Office of Advanced Scientific Computer Research. The project was a collaboration itself uniting fusion scientists from General Atomics, MIT, and PPPL and computer scientists from ANL, LBNL, Princeton University, and the University of Utah to form a coordinated team. The group leveraged existing computer science technology where possible and extended or created new capabilities where required. Developing a reliable energy system that is economically and environmentally sustainable is the long-term goal of Fusion Energy Science (FES) research. In the U.S., FES experimental research is centered at three large facilities with a replacement value of over $1B. As these experiments have increased in size and complexity, there has been a concurrent growth in the number and importance of collaborations among large groups at the experimental sites and smaller groups located nationwide. Teaming with the experimental community is a theoretical and simulation community whose efforts range from applied analysis of experimental data to fundamental theory (e.g., realistic nonlinear 3D plasma models) that run on massively parallel computers. Looking toward the future, the large-scale experiments needed for FES research are staffed by correspondingly large, globally dispersed teams. The fusion program will be increasingly oriented toward the International Thermonuclear Experimental Reactor (ITER) where even now, a decade before operation begins, a large

  11. Ion Rings for Magnetic Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Greenly, John, B.

    2005-07-31

    This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation

  12. Magnetized Plasma Compression for Fusion Energy

    Science.gov (United States)

    Degnan, James; Grabowski, Christopher; Domonkos, Matthew; Amdahl, David

    2013-10-01

    Magnetized Plasma Compression (MPC) uses magnetic inhibition of thermal conduction and enhancement of charge particle product capture to greatly reduce the temporal and spatial compression required relative to un-magnetized inertial fusion (IFE)--to microseconds, centimeters vs nanoseconds, sub-millimeter. MPC greatly reduces the required confinement time relative to MFE--to microseconds vs minutes. Proof of principle can be demonstrated or refuted using high current pulsed power driven compression of magnetized plasmas using magnetic pressure driven implosions of metal shells, known as imploding liners. This can be done at a cost of a few tens of millions of dollars. If demonstrated, it becomes worthwhile to develop repetitive implosion drivers. One approach is to use arrays of heavy ion beams for energy production, though with much less temporal and spatial compression than that envisioned for un-magnetized IFE, with larger compression targets, and with much less ambitious compression ratios. A less expensive, repetitive pulsed power driver, if feasible, would require engineering development for transient, rapidly replaceable transmission lines such as envisioned by Sandia National Laboratories. Supported by DOE-OFES.

  13. Magnetic confinement fusion energy research

    Energy Technology Data Exchange (ETDEWEB)

    Grad, H

    1977-03-01

    Controlled Thermonuclear Fusion offers probably the only relatively clean energy solution with completely inexhaustible fuel and unlimited power capacity. The scientific and technological problem consists in magnetically confining a hot, dense plasma (pressure several to hundreds of atmospheres, temperature 10/sup 8/ degrees or more) for an appreciable fraction of a second. The scientific and mathematical problem is to describe the behavior, such as confinement, stability, flow, compression, heating, energy transfer and diffusion of this medium in the presence of electromagnetic fields just as we now can for air or steam. Some of the extant theory consists of applications, routine or ingenious, of known mathematical structures in the theory of differential equations and in traditional analysis. Other applications of known mathematical structures offer surprises and new insights: the coordination between sub-supersonic and elliptic-hyperbolic is fractured; supersonic propagation goes upstream; etc. Other completely nonstandard mathematical structures with significant theory are being rapidly uncovered (and somewhat less rapidly understood) such as non-elliptic variational equations and new types of weak solutions. It is these new mathematical structures which one should expect to supply the foundation for the next generation's pure mathematics, if history is a guide. Despite the substantial effort over a period of some twenty years, there are still basic and important scintific and mathematical discoveries to be made, lying just beneath the surface.

  14. Generic Magnetic Fusion Reactor Revisited

    Science.gov (United States)

    Sheffield, John; Milora, Stanley

    2015-11-01

    The original Generic Magnetic Fusion Reactor paper was published in 1986. This update describes what has changed in 30 years. Notably, the construction of ITER is providing important benchmark numbers for technologies and costs. In addition, we use a more conservative neutron wall flux and fluence. But these cost-increasing factors are offset by greater optimism on the thermal-electric conversion efficiency and potential availability. The main examples show the cost of electricity (COE) as a function of aspect ratio and neutron flux to the first wall. The dependence of the COE on availability, thermo-electric efficiency, electrical power output, and the present day's low interest rates is also discussed. Interestingly, at fixed aspect ratio there is a shallow minimum in the COE at neutron flux around 2.5 MW/m2. The possibility of operating with only a small COE penalty at even lower wall loadings (to 1.0 MW/m2 at larger plant size) and the use of niobium-titanium coils are also investigated. J. Sheffield was supported by ORNL subcontract 4000088999 with the University of Tennessee.

  15. Magnet operating experience review for fusion applications

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, L.C.

    1991-11-01

    This report presents a review of magnet operating experiences for normal-conducting and superconducting magnets from fusion, particle accelerator, medical technology, and magnetohydrodynamics research areas. Safety relevant magnet operating experiences are presented to provide feedback on field performance of existing designs and to point out the operational safety concerns. Quantitative estimates of magnet component failure rates and accident event frequencies are also presented, based on field experience and on performance of similar components in other industries.

  16. Magnet operating experience review for fusion applications

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, L.C.

    1991-11-01

    This report presents a review of magnet operating experiences for normal-conducting and superconducting magnets from fusion, particle accelerator, medical technology, and magnetohydrodynamics research areas. Safety relevant magnet operating experiences are presented to provide feedback on field performance of existing designs and to point out the operational safety concerns. Quantitative estimates of magnet component failure rates and accident event frequencies are also presented, based on field experience and on performance of similar components in other industries.

  17. Reactor potential for magnetized target fusion

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, J.E

    2001-06-01

    Magnetized Target Fusion (MTF) is a possible pathway to thermonuclear fusion different from both magnetic fusion and inertial confinement fusion. An imploding cylindrical metal liner compresses a preheated and magnetized plasma configuration until thermonuclear conditions are achieved. In this report the Magnetized Target Fusion concept is evaluated and a zero-dimensional computer model of the plasma, liner and circuit as a connected system is designed. The results of running this code are that thermonuclear conditions are achieved indeed, but only during a very short time. At peak compression the pressure from the compressed plasma and magnetic field is so large reversing the liner implosion into an explosion. The time period of liner motion reversal is termed the dwell time and is crucial to the performance of the fusion system. Parameters as liner thickness and plasma density are certainly of significant importance to the dwell time, but it seems like a reactor based on the MTF principle hardly can become economic if not innovative solutions are introduced. In the report two such solutions are presented as well.

  18. Safety of magnetic fusion facilities: Guidance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This document provides guidance for the implementation of the requirements identified in DOE-STD-6002-96, Safety of Magnetic Fusion Facilities: Requirements. This guidance is intended for the managers, designers, operators, and other personnel with safety responsibilities for facilities designated as magnetic fusion facilities. While the requirements in DOE-STD-6002-96 are generally applicable to a wide range of fusion facilities, this Standard, DOE-STD-6003-96, is concerned mainly with the implementation of those requirements in large facilities such as the International Thermonuclear Experimental Reactor (ITER). Using a risk-based prioritization, the concepts presented here may also be applied to other magnetic fusion facilities. This Standard is oriented toward regulation in the Department of Energy (DOE) environment as opposed to regulation by other regulatory agencies. As the need for guidance involving other types of fusion facilities or other regulatory environments emerges, additional guidance volumes should be prepared. The concepts, processes, and recommendations set forth here are for guidance only. They will contribute to safety at magnetic fusion facilities.

  19. High-Gain Magnetized Inertial Fusion

    Science.gov (United States)

    Slutz, Stephen A.; Vesey, Roger A.

    2012-01-01

    Magnetized inertial fusion (MIF) could substantially ease the difficulty of reaching plasma conditions required for significant fusion yields, but it has been widely accepted that the gain is not sufficient for fusion energy. Numerical simulations are presented showing that high-gain MIF is possible in cylindrical liner implosions based on the MagLIF concept [S. A. Slutz et al Phys. Plasmas 17, 056303 (2010)PHPAEN1070-664X10.1063/1.3333505] with the addition of a cryogenic layer of deuterium-tritium (DT). These simulations show that a burn wave propagates radially from the magnetized hot spot into the surrounding much denser cold DT given sufficient hot-spot areal density. For a drive current of 60 MA the simulated gain exceeds 100, which is more than adequate for fusion energy applications. The simulated gain exceeds 1000 for a drive current of 70 MA.

  20. Perspectives on Magnetized Target Fusion Power Plants

    Science.gov (United States)

    Miller, R. L.

    2007-06-01

    One approach to Magnetized Target Fusion (MTF) builds upon the ongoing experimental effort (FRX-L) to generate a Field Reversed Configuration (FRC) target plasma suitable for translation and cylindrical-liner (i.e., converging flux conserver) implosion. Numerical modeling is underway to elucidate key performance drivers for possible future power-plant extrapolations. The fusion gain, Q (ratio of DT fusion yield to the sum of initial liner kinetic energy plus plasma formation energy), sets the power-plant duty cycle for a nominal design electric power [ e.g. 1,000 MWe(net)]. A pulsed MTF power plant of this type derives from the historic Fast Liner Reactor (FLR) concept and shares attributes with the recent Inertial Fusion Energy (IFE) Z-pinch and laser-driven pellet HYLIFE-II conceptual designs.

  1. Acoustically Driven Magnetized Target Fusion At General Fusion: An Overview

    Science.gov (United States)

    O'Shea, Peter; Laberge, M.; Donaldson, M.; Delage, M.; the Fusion Team, General

    2016-10-01

    Magnetized Target Fusion (MTF) involves compressing an initial magnetically confined plasma of about 1e23 m-3, 100eV, 7 Tesla, 20 cm radius, >100 μsec life with a 1000x volume compression in 100 microseconds. If near adiabatic compression is achieved, the final plasma of 1e26 m-3, 10keV, 700 Tesla, 2 cm radius, confined for 10 μsec would produce interesting fusion energy gain. General Fusion (GF) is developing an acoustic compression system using pneumatic pistons focusing a shock wave on the CT plasma in the center of a 3 m diameter sphere filled with liquid lead-lithium. Low cost driver, straightforward heat extraction, good tritium breeding ratio and excellent neutron protection could lead to a practical power plant. GF (65 employees) has an active plasma R&D program including both full scale and reduced scale plasma experiments and simulation of both. Although acoustic driven compression of full scale plasmas is the end goal, present compression studies use reduced scale plasmas and chemically accelerated Aluminum liners. We will review results from our plasma target development, motivate and review the results of dynamic compression field tests and briefly describe the work to date on the acoustic driver front.

  2. Integrated simulation and modeling capability for alternate magnetic fusion concepts

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B. I.; Hooper, E.B.; Jarboe, T. R.; LoDestro, L. L.; Pearlstein, L. D.; Prager, S. C.; Sarff, J. S.

    1998-11-03

    This document summarizes a strategic study addressing the development of a comprehensive modeling and simulation capability for magnetic fusion experiments with particular emphasis on devices that are alternatives to the mainline tokamak device. A code development project in this area supports two defined strategic thrust areas in the Magnetic Fusion Energy Program: (1) comprehensive simulation and modeling of magnetic fusion experiments and (2) development, operation, and modeling of magnetic fusion alternate- concept experiment

  3. Nonlinear laser-plasma interaction in magnetized liner inertial fusion

    Science.gov (United States)

    Geissel, Matthias; Awe, T. J.; Bliss, D. E.; Campbell, M. E.; Gomez, M. R.; Harding, E.; Harvey-Thompson, A. J.; Hansen, S. B.; Jennings, C.; Kimmel, M. W.; Knapp, P.; Lewis, S. M.; McBride, R. D.; Peterson, K.; Schollmeier, M.; Scoglietti, D. J.; Sefkow, A. B.; Shores, J. E.; Sinars, D. B.; Slutz, S. A.; Smith, I. C.; Speas, C. S.; Vesey, R. A.; Porter, J. L.

    2016-03-01

    Sandia National Laboratories is pursuing a variation of Magneto-Inertial Fusion called Magnetized Liner Inertial Fusion, or MagLIF. The MagLIF approach requires magnetization of the deuterium fuel, which is accomplished by an initial external B-Field and laser-driven pre-heat. While magnetization is crucial to the concept, it is challenging to couple sufficient energy to the fuel, since laser-plasma instabilities exist, and a compromise between laser spot size, laser entrance window thickness, and fuel density must be found. Nonlinear processes in laser plasma interaction, or laser-plasma instabilities (LPI), complicate the deposition of laser energy by enhanced absorption, backscatter, filamentation and beam-spray. Key LPI processes are determined, and mitigation methods are discussed. Results with and without improvement measures are presented.

  4. Impact of target modifications on Magnetized Liner Inertial Fusion performance

    Science.gov (United States)

    Gomez, Matthew; Knapp, Patrick; Sefkow, Adam; Slutz, Stephen; Awe, Thomas; Hansen, Stephanie; Hahn, Kelly; Harding, Eric; Jennings, Christopher; McBride, Ryan; Sinars, Daniel; Rochau, Gregory; Peterson, Kyle

    2015-11-01

    Magnetized Liner Inertial Fusion (MagLIF) is a magnetically-driven fusion concept in which an axial magnetic field and laser heating are used to relax the implosion requirements of inertial confinement fusion. Initial experiments demonstrated the promise of the concept with relatively high yields (primary DD = 2e12), ion temperatures (2.5 keV), and magnetic field-radius products (>0.3 MG-cm). In order to better understand the portions of parameter space in which MagLIF can operate effectively, a series of experiments are being conducted to test the impact of various changes (e.g., laser-entrance-hole window thickness, imploding height of the target, endcap material, laser energy, laser spot size, initial fuel density). The impact of these changes on target performance (primary neutron yield, ion temperature, stagnation volume, etc.) will be discussed. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  5. Realizing Technologies for Magnetized Target Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Wurden, Glen A. [Los Alamos National Laboratory

    2012-08-24

    Researchers are making progress with a range of magneto-inertial fusion (MIF) concepts. All of these approaches use the addition of a magnetic field to a target plasma, and then compress the plasma to fusion conditions. The beauty of MIF is that driver power requirements are reduced, compared to classical inertial fusion approaches, and simultaneously the compression timescales can be longer, and required implosion velocities are slower. The presence of a sufficiently large Bfield expands the accessibility to ignition, even at lower values of the density-radius product, and can confine fusion alphas. A key constraint is that the lifetime of the MIF target plasma has to be matched to the timescale of the driver technology (whether liners, heavy ions, or lasers). To achieve sufficient burn-up fraction, scaling suggests that larger yields are more effective. To handle the larger yields (GJ level), thick liquid wall chambers are certainly desired (no plasma/neutron damage materials problem) and probably required. With larger yields, slower repetition rates ({approx}0.1-1 Hz) for this intrinsically pulsed approach to fusion are possible, which means that chamber clearing between pulses can be accomplished on timescales that are compatible with simple clearing techniques (flowing liquid droplet curtains). However, demonstration of the required reliable delivery of hundreds of MJ of energy, for millions of pulses per year, is an ongoing pulsed power technical challenge.

  6. Laser-Driven Magnetized Liner Inertial Fusion on OMEGA

    Science.gov (United States)

    Barnak, D. H.

    2016-10-01

    Magneto-inertial fusion (MIF) is an approach that combines the implosion and compression of fusion fuel (a hallmark of inertial fusion) with strongly magnetized plasmas that suppress electron heat losses (a hallmark of magnetic fusion). It is of interest because it could potentially reduce some of the traditional velocity, pressure, and convergence ratio requirements of inertial confinement fusion (ICF). The magnetized liner inertial fusion (MagLIF) concept being studied at the Z Pulsed-Power Facility is a key target concept in the U.S. ICF Program. Laser-driven MagLIF is being developed to enable a test of the scaling of MagLIF over a range of absorbed energy from of the order of 20 kJ (on OMEGA) to 500 kJ (on Z). It is also valuable as a platform for studying the key physics of MIF. An energy-scaled point design has been developed for the Omega Laser Facility that is roughly 10 × smaller in linear dimensions than Z MagLIF targets. A 0.6-mm-outer-diam plastic cylinder filled with 2.4 mg/cm3 of D2 is placed in a 10-T axial magnetic field, generated by MIFEDS (magneto-inertial fusion electrical discharge system), the cylinder is compressed by 40 OMEGA beams, and the gas fill is preheated by a single OMEGA beam propagating along the axis. Preheating to >100 eV and axially uniform compression over a 0.7-mm height have been demonstrated, separately, in a series of preparatory experiments that meet our initial expectations. Preliminary results from the first integrated experiments combining magnetization, compression, and preheat will be reported for the first time. The scaling of laser-driven MagLIF from OMEGA up to the 1800 kJ available on the NIF (National Ignition Facility) will also be described briefly. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  7. Gorgon simulations of Magnetized Liner Inertial Fusion

    Science.gov (United States)

    Roeltgen, Jonathan; Jennings, Christopher; Sefkow, Adam; Slutz, Stephen

    2012-10-01

    Substantial fusion yields are predicted with pulsed power machines driving cylindrical liner implosions with preheated and magnetized deuterium-tritium [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)]. The Rayleigh-Taylor instability is the most likely mechanism that could degrade the fusion yield of this concept which we call Magnetized Liner Inertial Fusion (MagLIF). Gorgon is a 3D magnetohydrodynamics code that is well suited to simulating the effects of 3D Magneto-Rayleigh-Taylor instabilities. It has successfully simulated wire array z-pinches in 3D. We plan to use Gorgon to simulate the MagLIF concept in 3D, but first we are performing 1D simulations to test the essential physics necessary to simulate the MagLIF concept, for example bremsstrahlung losses from the fuel and the inhibition of transport by the magnetic field. We will present 1D Gorgon results of optimized MagLIF yields as a function of drive current.

  8. Pressure measurements in magnetic-fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Dylla, H.F.

    1981-11-01

    Accurate pressure measurements are important in magnetic fusion devices for: (1) plasma diagnostic measurements of particle balance and ion temperature; (2) discharge cleaning optimization; (3) vacuum system performance; and (4) tritium accountability. This paper reviews the application, required accuracy, and suitable instrumentation for these measurements. Demonstrated uses of ionization-type and capacitance-diaphragm gauges for various pressure and gas-flow measurements in tokamaks are presented, with specific reference to the effects of magnetic fields on gauge performance and the problems associated with gauge calibration.

  9. Effects of magnetization on fusion product trapping and secondary neutron spectra

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, P. F.; Schmit, P. F.; Hansen, S. B.; Gomez, M. R.; Hahn, K. D.; Sinars, D. B.; Peterson, K. J.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Harding, E.; Jennings, C. A.; Desjarlais, M. P.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Geissel, M.; Harvey-Thompson, A. J.; Porter, J. L.; Rochau, G. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); and others

    2015-05-15

    By magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used to infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner Inertial Fusion experiments conducted on the Z machine at Sandia National Laboratories. We show that in these experiments BR ≈ 0.34(+0.14/−0.06) MG · cm, a ∼ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. This is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux.

  10. Magnetized Target Fusion Collaboration. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Slough, John

    2012-04-18

    Nuclear fusion has the potential to satisfy the prodigious power that the world will demand in the future, but it has yet to be harnessed as a practical energy source. The entry of fusion as a viable, competitive source of power has been stymied by the challenge of finding an economical way to provide for the confinement and heating of the plasma fuel. It is the contention here that a simpler path to fusion can be achieved by creating fusion conditions in a different regime at small scale (~ a few cm). One such program now under study, referred to as Magnetized Target Fusion (MTF), is directed at obtaining fusion in this high energy density regime by rapidly compressing a compact toroidal plasmoid commonly referred to as a Field Reversed Configuration (FRC). To make fusion practical at this smaller scale, an efficient method for compressing the FRC to fusion gain conditions is required. In one variant of MTF a conducting metal shell is imploded electrically. This radially compresses and heats the FRC plasmoid to fusion conditions. The closed magnetic field in the target plasmoid suppresses the thermal transport to the confining shell, thus lowering the imploding power needed to compress the target. The undertaking described in this report was to provide a suitable target FRC, as well as a simple and robust method for inserting and stopping the FRC within the imploding liner. The FRC must also survive during the time it takes for the metal liner to compress the FRC target. The initial work at the UW was focused on developing adequate preionization and flux trapping that were found to be essential in past experiments for obtaining the density, flux and most critically, FRC lifetime required for MTF. The timescale for testing and development of such a source can be rapidly accelerated by taking advantage of a new facility funded by the Department of Energy. At this facility, two inductive plasma accelerators (IPA) were constructed and tested. Recent experiments with

  11. Magnetic compression/magnetized target fusion (MAGO/MTF), an update

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, R.C.; Lindemuth, I.R.

    1998-03-01

    Magnetized Target Fusion (MTF) was reported in two papers at the First Symposium on Current Trends in International Fusion Research. MTF is intermediate between two very different mainline approaches to fusion: Inertial Confinement Fusion (ICF) and magnetic confinement fusion (MCF). The only US MTF experiments in which a target plasma was compressed were the Sandia National Laboratory ``Phi targets``. Despite the very interesting results from that series of experiments, the research was not pursued, and other embodiments of MTF concept such as the Fast Liner were unable to attract the financial support needed for a firm proof of principle. A mapping of the parameter space for MTF showed the significant features of this approach. The All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) has an on-going interest in this approach to thermonuclear fusion, and Los Alamos National Laboratory (LANL) and VNIIEF have done joint target plasma generation experiments relevant to MTF referred to as MAGO (transliteration of the Russian acronym for magnetic compression). The MAGO II experiment appears to have achieved on the order of 200 eV and over 100 KG, so that adiabatic compression with a relatively small convergence could bring the plasma to fusion temperatures. In addition, there are other experiments being pursued for target plasma generation and proof of principle. This paper summarizes the previous reports on MTF and MAGO and presents the progress that has been made over the past three years in creating a target plasma that is suitable for compression to provide a scientific proof of principle experiment for MAGO/MTF.

  12. Magnetic Compression Experiment at General Fusion

    Science.gov (United States)

    Dunlea, Carl; Howard, Stephen; Epp, Kelly; Zawalski, Wade; Kim, Charlson; Fusion Team, General

    2016-10-01

    The magnetic compression experiment at General Fusion was designed as a repetitive non-destructive test to study plasma physics applicable to Magnetic Target Fusion compression. A spheromak compact torus (CT) is formed with a co-axial gun into a containment region with an hour-glass shaped inner flux conserver, and an insulating outer wall. The experiment has external coils to keep the CT off the outer wall (levitation) and then rapidly compress it inwards. Experiments used a variety of levitation/compression field profiles. The optimal configuration was seen to improve levitated CT lifetime by around 50% over that with the original design field. Suppression of impurity influx to the plasma is thought to be a significant factor in the improvement, as supported by spectrometer data. Improved levitation field may reduce the amount of edge plasma and current that intersects the insulating outer wall during the formation process. Higher formation current and stuffing field, and correspondingly higher CT flux, was possible with the improved configuration. Significant field and density compression factors were routinely observed. The level of MHD activity was reduced, and lifetime was increased further by matching the decay rate of the levitation field to that of the CT fields. Details of experimental results and comparisons to equilibrium models and MHD simulations will be presented.

  13. Auto-magnetizing liners for magnetized inertial fusion

    Science.gov (United States)

    Slutz, S. A.; Jennings, C. A.; Awe, T. J.; Shipley, G. A.; Hutsel, B. T.; Lamppa, D. C.

    2017-01-01

    The MagLIF (Magnetized Liner Inertial Fusion) concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)] has demonstrated fusion-relevant plasma conditions [Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z accelerator using external field coils to magnetize the fuel before compression. We present a novel concept (AutoMag), which uses a composite liner with helical conduction paths separated by insulating material to provide fuel magnetization from the early part of the drive current, which by design rises slowly enough to avoid electrical breakdown of the insulators. Once the magnetization field is established, the drive current rises more quickly, which causes the insulators to break down allowing the drive current to follow an axial path and implode the liner in the conventional z-pinch manner. There are two important advantages to AutoMag over external field coils for the operation of MagLIF. Low inductance magnetically insulated power feeds can be used to increase the drive current, and AutoMag does not interfere with diagnostic access. Also, AutoMag enables a pathway to energy applications for MagLIF, since expensive field coils will not be damaged each shot. Finally, it should be possible to generate Field Reversed Configurations (FRC) by using both external field coils and AutoMag in opposite polarities. This would provide a means to studying FRC liner implosions on the 100 ns time scale.

  14. Magnetized Target Fusion (MTF): Principles, Status, and International Collaboration

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, R.C.

    1998-11-16

    Magnetized target fusion (MTF) is an approach to thermonuclear fusion that is intermediate between the two extremes of inertial and magnetic confinement. Target plasma preparation is followed by compression to fusion conditions. The use of a magnetic field to reduce electron thermal conduction and potentially enhance DT alpha energy deposition allows the compression rate to be drastically reduced relative to that for inertial confinement fusion. This leads to compact systems with target driver power and intensity requirements that are orders of magnitude lower than for ICF. A liner on plasma experiment has been proposed to provide a firm proof of principle for MTF.

  15. Magnetized Target Fusion Driven by Plasma Liners

    Science.gov (United States)

    Thio, Y. C. Francis; Cassibry, Jason; Eskridge, Richard; Kirkpatrick, Ronald C.; Knapp, Charles E.; Lee, Michael; Martin, Adam; Smith, James; Wu, S. T.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    For practical applications of magnetized target fusion, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Quasi-spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a quasi-spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). Theoretical analysis and computer modeling of the concept are presented. It is shown that, with the appropriate choice of the flow parameters in the liner and the target, the impact between the liner and the target plasma can be made to be shockless in the liner or to generate at most a very weak shock in the liner. Additional information is contained in the original extended abstract.

  16. Fusion-neutron measurements for magnetized liner inertial fusion experiments on the Z accelerator

    Science.gov (United States)

    Hahn, K. D.; Chandler, G. A.; Ruiz, C. L.; Cooper, G. W.; Gomez, M. R.; Slutz, S.; Sefkow, A. B.; Sinars, D. B.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Harding, E.; Jennings, C. A.; Awe, T. J.; Geissel, M.; Rovang, D. C.; Torres, J. A.; Bur, J. A.; Cuneo, M. E.; Glebov, V. Yu; Harvey-Thompson, A. J.; Herrman, M. C.; Hess, M. H.; Johns, O.; Jones, B.; Lamppa, D. C.; Lash, J. S.; Martin, M. R.; McBride, R. D.; Peterson, K. J.; Porter, J. L.; Reneker, J.; Robertson, G. K.; Rochau, G. A.; Savage, M. E.; Smith, I. C.; Styron, J. D.; Vesey, R. A.

    2016-05-01

    Several magnetized liner inertial fusion (MagLIF) experiments have been conducted on the Z accelerator at Sandia National Laboratories since late 2013. Measurements of the primary DD (2.45 MeV) neutrons for these experiments suggest that the neutron production is thermonuclear. Primary DD yields up to 3e12 with ion temperatures ∼2-3 keV have been achieved. Measurements of the secondary DT (14 MeV) neutrons indicate that the fuel is significantly magnetized. Measurements of down-scattered neutrons from the beryllium liner suggest ρRliner∼1g/cm2. Neutron bang times, estimated from neutron time-of-flight (nTOF) measurements, coincide with peak x-ray production. Plans to improve and expand the Z neutron diagnostic suite include neutron burn-history diagnostics, increased sensitivity and higher precision nTOF detectors, and neutron recoil-based yield and spectral measurements.

  17. Experimental progress toward magnetized liner inertial fusion on Z

    Science.gov (United States)

    Sinars, Daniel; Herrmann, Mark; Cuneo, Michael; Lamppa, Derek; Lopez, Andrew; McBride, Ryan; Rovang, Dean; Hanson, David; Harding, Eric; Nakhleh, Charles; Slutz, Stephen; Vesey, Roger; Sefkow, Adam; Peterson, Kyle

    2011-10-01

    Yields exceeding 100 kJ may be possible on the 25 MA Z facility at Sandia using the implosion of cylindrical metal liners onto magnetized (>10 T) and preheated (100-500 eV) deuterium-tritium fuel [S.A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. The fusion fuel in such targets absorbs about 100 kJ, so a 100 kJ yield would be `scientific breakeven.' Suitable liner targets (Al and Be) have been fabricated and used in experiments on the magneto-Rayleigh-Taylor instability. Magnetic field coil prototypes for >10 T axial fields are being tested. Preheat experiments using the multi-kJ Z-Beamlet laser are planned. Cryogenic deuterium fuel systems have been developed. Integrated magnetized liner inertial fusion (MagLIF) tests using deuterium fuel are expected in 2013. Sandia is a multiprogram laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  18. Magnetic field considerations in fusion power plant environs

    Energy Technology Data Exchange (ETDEWEB)

    Liemohn, H.B.; Lessor, D.L.; Duane, B.H.

    1976-09-01

    A summary of magnetic field production mechanisms and effects is given. Discussions are included on the following areas: (1) stray magnetic and electric fields from tokamaks, (2) methods for reducing magnetic fields, (3) economics of magnetic field reductions, (4) forces on magnetizable objects near magnetic confinement fusion reactors, (5) electric field transients in tokamaks, (6) attenuation and decay of electromagnetic fields, and (7) magnetic field transients from tokamak malfunctions.

  19. High temperature superconductor cable concepts for fusion magnets

    CERN Document Server

    AUTHOR|(CDS)2078397

    2013-01-01

    Three concepts of high temperature superconductor cables carrying kA currents (RACC, CORC and TSTC) are investigated, optimized and evaluated in the scope of their applicability as conductor in fusion magnets. The magnetic field and temperature dependence of the cables is measured; the thermal expansion and conductivity of structure, insulation and filling materials are investigated. High temperature superconductor winding packs for fusion magnets are calculated and compared with corresponding low temperature superconductor cases.

  20. Demonstration of thermonuclear conditions in Magnetized Liner Inertial Fusion experiments

    Science.gov (United States)

    Gomez, Matthew

    2014-10-01

    The Magnetized Liner Inertial Fusion concept utilizes a magnetic field and laser heating to relax the implosion requirements to achieve inertial confinement fusion. The first experiments to test the concept were recently conducted utilizing the 19 MA, 100 ns Z machine, the 2.5 kJ, 1 TW Z Beamlet laser, and the 10 T Applied B-field on Z coils. Despite the relatively slow implosion velocity (70 km/s) in these experiments, electron and ion temperatures at stagnation were approximately 3 keV, and thermonuclear DD neutron yields up to 2e12 have been produced. X-ray emission from the fuel at stagnation had a width ranging from 60-120 microns over a roughly 6 mm height and lasted approximately 2 ns. X-ray spectra from these experiments are consistent with a stagnation density of the hot fuel equal to 0.4 g/cm3 . In these experiments 1-5e10 secondary DT neutrons were produced. Given that the areal density of the plasma was approximately 2 mg/cm2, this indicates the stagnation plasma was significantly magnetized. This is consistent with the anisotropy observed in the DT neutron time of flight spectra. Control experiments where the laser and/or magnetic field were not utilized failed to produce stagnation temperatures greater than 1 keV and DD yields greater than 1e10. An additional control experiment where the fuel contained a sufficient dopant fraction to radiate away the laser energy deposited in the fuel also failed to produce a relevant stagnation temperature. The results of these experiments are consistent with a thermonuclear neutron source. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  1. Compact magnetic confinement fusion: Spherical torus and compact torus

    Directory of Open Access Journals (Sweden)

    Zhe Gao

    2016-05-01

    Full Text Available The spherical torus (ST and compact torus (CT are two kinds of alternative magnetic confinement fusion concepts with compact geometry. The ST is actually a sub-category of tokamak with a low aspect ratio; while the CT is a toroidal magnetic configuration with a simply-connected geometry including spheromak and field reversed pinch. The ST and CT have potential advantages for ultimate fusion reactor; while at present they can also provide unique fusion science and technology contributions for mainstream fusion research. However, some critical scientific and technology issues should be extensively investigated.

  2. Axisymmetric Magnetic Mirror Fusion-Fission Hybrid

    Energy Technology Data Exchange (ETDEWEB)

    Moir, R. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martovetsky, N. N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Molvik, A. W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ryutov, D. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Simonen, T. C. [Univ. of California, Berkeley, CA (United States)

    2011-05-13

    The achieved performance of the gas dynamic trap version of magnetic mirrors and today’s technology we believe are sufficient with modest further efforts for a neutron source for material testing (Q=Pfusion/Pinput~0.1). The performance needed for commercial power production requires considerable further advances to achieve the necessary high Q>>10. An early application of the mirror, requiring intermediate performance and intermediate values of Q~1 are the hybrid applications. The Axisymmetric Mirror has a number of attractive features as a driver for a fusion-fission hybrid system: geometrical simplicity, inherently steady-state operation, and the presence of the natural divertors in the form of end tanks. This level of physics performance has the virtue of low risk and only modest R&D needed and its simplicity promises economy advantages. Operation at Q~1 allows for relatively low electron temperatures, in the range of 4 keV, for the DT injection energy ~ 80 keV. A simple mirror with the plasma diameter of 1 m and mirror-to-mirror length of 35 m is discussed. Simple circular superconducting coils are based on today’s technology. The positive ion neutral beams are similar to existing units but designed for steady state. A brief qualitative discussion of three groups of physics issues is presented: axial heat loss, MHD stability in the axisymmetric geometry, microstability of sloshing ions. Burning fission reactor wastes by fissioning actinides (transuranics: Pu, Np, Am, Cm, .. or just minor actinides: Np, Am, Cm, …) in the hybrid will multiply fusion’s energy by a factor of ~10 or more and diminish the Q needed to less than 1 to overcome the cost of recirculating power for good economics. The economic value of destroying actinides by fissioning is rather low based on either the cost of long-term storage or even deep geologic disposal so most of the revenues of hybrids will come from electrical power. Hybrids that obtain revenues from

  3. Computational modeling of joint U.S.-Russian experiments relevant to magnetic compression/magnetized target fusion (MAGO/MTF)

    Energy Technology Data Exchange (ETDEWEB)

    Sheehey, P.T.; Faehl, R.J.; Kirkpatrick, R.C.; Lindemuth, I.R. [Los Alamos National Lab., NM (United States)

    1997-12-31

    Magnetized Target Fusion (MTF) experiments, in which a preheated and magnetized target plasma is hydrodynamically compressed to fusion conditions, present some challenging computational modeling problems. Recently, joint experiments relevant to MTF (Russian acronym MAGO, for Magnitnoye Obzhatiye, or magnetic compression) have been performed by Los Alamos National Laboratory and the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF). Modeling of target plasmas must accurately predict plasma densities, temperatures, fields, and lifetime; dense plasma interactions with wall materials must be characterized. Modeling of magnetically driven imploding solid liners, for compression of target plasmas, must address issues such as Rayleigh-Taylor instability growth in the presence of material strength, and glide plane-liner interactions. Proposed experiments involving liner-on-plasma compressions to fusion conditions will require integrated target plasma and liner calculations. Detailed comparison of the modeling results with experiment will be presented.

  4. BOOK REVIEW: Advanced Diagnostics for Magnetic and Inertial Confinement Fusion

    Science.gov (United States)

    Stott, PE; Wootton, A.; Gorini, G.; Sindoni, E.; Batani, D.

    2003-02-01

    diagnostics. The resulting collection of papers is comprehensive and wide-ranging and all of the major laboratories in Europe, the US, and Japan are represented. There is important discussion on the development of diagnostics for the National Ignition Facility, LMJ, and future ultra-high intensity laser experiments as well as papers on wire array z-pinch experiments. It is especially useful to have the contributions from inertial confinement fusion experiments intermingled with those from magnetic confinement fusion. The separation between these two approaches to fusion is often unfortunately large, so one of the pleasing things about this book is that it is very easy for readers familiar with experimental research in one area to compare `state of the art' plasma diagnostics in the other area. Hopefully this will facilitate the development of new ideas in both areas. This book is a conference proceedings and as such, almost all of the papers included are quite brief and are highly technical. Consequently, the book is not particularly pedagogical and would be most useful to researchers already working in this area of physics. For these readers, however, Advanced Diagnostics for Magnetic and Inertial Confinement Fusion is an excellent overview of the present status of fusion plasma diagnostics. K Krushelnick

  5. Preliminary analysis of patent trends for magnetic fusion technology

    Energy Technology Data Exchange (ETDEWEB)

    Levine, L.O.; Ashton, W.B.; Campbell, R.S.

    1984-02-01

    This study presents a preliminary analysis of development trends in magnetic fusion technology based on data from US patents. The research is limited to identification and description of general patent activity and ownership characteristics for 373 patents. The results suggest that more detailed studies of fusion patents could provide useful R and D planning information.

  6. Fusion Materials Research at Oak Ridge National Laboratory in Fiscal Year 2015

    Energy Technology Data Exchange (ETDEWEB)

    Wiffen, F. W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Melton, Stephanie G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-12-01

    The realization of fusion energy is a formidable challenge with significant achievements resulting from close integration of the plasma physics and applied technology disciplines. Presently, the most significant technological challenge for the near-term experiments such as ITER, and next generation fusion power systems, is the inability of current materials and components to withstand the harsh fusion nuclear environment. The overarching goal of the Oak Ridge National Laboratory (ORNL) fusion materials program is to provide the applied materials science support and understanding to underpin the ongoing Department of Energy (DOE) Office of Science fusion energy program while developing materials for fusion power systems. In doing so the program continues to be integrated both with the larger United States (US) and international fusion materials communities, and with the international fusion design and technology communities.This document provides a summary of Fiscal Year (FY) 2015 activities supporting the Office of Science, Office of Fusion Energy Sciences Materials Research for Magnetic Fusion Energy (AT-60-20-10-0) carried out by ORNL. The organization of this report is mainly by material type, with sections on specific technical activities. Four projects selected in the Funding Opportunity Announcement (FOA) solicitation of late 2011 and funded in FY2012-FY2014 are identified by “FOA” in the titles. This report includes the final funded work of these projects, although ORNL plans to continue some of this work within the base program.

  7. Safety of magnetic fusion facilities: Volume 2, Guidance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This document provides guidance for the implementation of the requirements identified in Vol. 1 of this Standard. This guidance is intended for the managers, designers, operators, and other personnel with safety responsibilities for facilities designated as magnetic fusion facilities. While Vol. 1 is generally applicable in that requirements there apply to a wide range of fusion facilities, this volume is concerned mainly with large facilities such as the International Thermonuclear Experimental Reactor (ITER). Using a risk-based prioritization, the concepts presented here may also be applied to other magnetic fusion facilities. This volume is oriented toward regulation in the Department of Energy (DOE) environment.

  8. The Parameter Space of Magnetized Target Fusion (aka Magneto-Inertial Fusion)

    Science.gov (United States)

    Lindemuth, Irvin

    2016-10-01

    Magnetized Target Fusion (MTF), aka Magneto-Inertial Fusion (MIF), is an approach to fusion that compresses a preformed, magnetized (but not necessarily magnetically confined) plasma with an imploding liner or pusher. MTF/MIF operates in a density regime in between the eleven orders of magnitude (1011) in density that separate inertial confinement fusion (ICF) from magnetic confinement fusion MCF. Compared to MCF, the higher density, shorter confinement times, and compressional heating as the dominant heating mechanism potentially reduce the impact of magnetic instabilities. Compared to ICF, the magnetically reduced thermal transport and lower density leads to orders-of-magnitude reduction in the difficult-to-achieve areal-density parameter and a significant reduction in required implosion velocity and radial convergence, potentially reducing the deleterious effects of implosion hydrodynamic instabilities. This tutorial presents fundamental analysis and simple time-dependent modeling to show where significant fusion gain might be achieved in the intermediate-density regime. The analysis shows that the fusion design space is potentially a continuum between ICF and MCF but practical considerations limit the space in which ignition might be obtained. Generic time-dependent modeling addresses the key physics requirements and defines ``ball-park'' values needed for target-plasma initial density, temperature, and magnetic field and implosion system size, energy, and velocity. The modeling shows energy gains greater than 30 can potentially be achieved and that high gain may be obtained at low convergence ratios, e.g., less than 15. A non-exhaustive review of past and present MTF/MIF efforts is presented and the renewed interest in MTF/MIF within the US (e.g., ARPA-E's ALPHA program) and abroad is noted.

  9. Magnetic charge lattices, moduli spaces and fusion rules

    NARCIS (Netherlands)

    Kampmeijer, L.; Slingerland, J.K.; Schroers, B.J.; Bais, F.A.

    2009-01-01

    We analyze the labelling and fusion properties of magnetic charge sectors consisting of smooth BPS monopoles in Yang-Mills-Higgs theory with arbitrary gauge group G spontaneously broken to a subgroup H. The magnetic charges are restricted by a generalized Dirac quantization condition and by an inequ

  10. Inertial Confinement Fusion and the National Ignition Facility (NIF)

    Energy Technology Data Exchange (ETDEWEB)

    Ross, P.

    2012-08-29

    Inertial confinement fusion (ICF) seeks to provide sustainable fusion energy by compressing frozen deuterium and tritium fuel to extremely high densities. The advantages of fusion vs. fission are discussed, including total energy per reaction and energy per nucleon. The Lawson Criterion, defining the requirements for ignition, is derived and explained. Different confinement methods and their implications are discussed. The feasibility of creating a power plant using ICF is analyzed using realistic and feasible numbers. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is shown as a significant step forward toward making a fusion power plant based on ICF. NIF is the world’s largest laser, delivering 1.8 MJ of energy, with a peak power greater than 500 TW. NIF is actively striving toward the goal of fusion energy. Other uses for NIF are discussed.

  11. A semi-analytic model of magnetized liner inertial fusion

    OpenAIRE

    McBride, Ryan D.; Slutz, Stephen A.

    2015-01-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression...

  12. Computational problems in magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Killeen, J.

    1981-08-31

    Numerical calculations have had an important role in fusion research since its beginning, but the application of computers to plasma physics has advanced rapidly in the last few years. One reason for this is the increasing sophistication of the mathematical models of plasma behavior, and another is the increased speed and memory of the computers which made it reasonable to consider numerical simulation of fusion devices. The behavior of a plasma is simulated by a variety of numerical models. Some models used for short times give detailed knowledge of the plasma on a microscopic scale, while other models used for much longer times compute macroscopic properties of the plasma dynamics. The computer models used in fusion research are surveyed. One of the most active areas of research is in time-dependent, three-dimensional, resistive magnetohydrodynamic models. These codes are reviewed briefly.

  13. Fission and fusion scenarios for magnetic microswimmer clusters

    CERN Document Server

    Guzmán-Lastra, Francisca; Löwen, Hartmut

    2016-01-01

    Fission and fusion processes of particles clusters occur in many areas of physics and chemistry from subnuclear to astronomic length scales. Here we study fission and fusion of magnetic microswimmer clusters as governed by their hydrodynamic and dipolar interactions. Rich scenarios are found which depend crucially on whether the swimmer is a pusher or a puller. In particular a linear magnetic chain of pullers is stable while a pusher chain shows a cascade of fission (or disassembly) processes as the self-propulsion velocity is increased. Contrarily, magnetic ring clusters show fission for any type of swimmer. Moreover, we find a plethora of possible fusion (or assembly) scenarios if a single swimmer collides with a ringlike cluster and two rings spontaneously collide. Our predictions are obtained by computer simulations and verifiable in experiments on active colloidal Janus particles and magnetotactic bacteria.

  14. Diagnosing Magnetized Liner Inertial Fusion experiments on Z

    Science.gov (United States)

    Hansen, Stephanie

    2014-10-01

    Recent Magnetized Liner Inertial Fusion (MagLIF) experiments performed at Sandia's Z facility have demonstrated DD fusion neutron yields above 1012 and effective confinement of charged fusion products by the flux-compressed magnetic field signaled by >1010 secondary DT neutrons. The neutron diagnostics are complemented by an extensive suite of visible and x-ray diagnostics providing power, imaging, and spectroscopic data. This talk will present analyses of emission and absorption features from the imploding and stagnating plasma that provide a consistent picture of the magnetic drive and the temperatures, densities, mix, and gradients in the fuel and liner at stagnation. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  15. A semi-analytic model of magnetized liner inertial fusion

    CERN Document Server

    McBride, Ryan D

    2015-01-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized alpha-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original Ma...

  16. National Center for Multisource Information Fusion

    Science.gov (United States)

    2009-04-01

    situation, threat, and impact assessment ( JDL levels 2 and 3) as well as sensor management ( JDL level 4) and visualization. While much of the research...Situation Awareness, JDL , Modeling and Simulation, Visualization 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF...appropriate sections.      3    2 Information Fusion Research and Development (4.1.1)    The  Joint Director’s  Laboratory  ( JDL )  fusion model

  17. Cost assessment of a generic magnetic fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, J.; Dory, R.A.; Cohn, S.M.; Delene, J.G.; Parsly, L.F.; Ashby, D.E.T.F.; Reiersen, W.T.

    1986-03-01

    A generic reactor model is used to examine the economic viability of generating electricity by magnetic fusion. The simple model uses components that are representative of those used in previous reactor studies of deuterium-tritium-burning tokamaks, stellarators, bumpy tori, reversed-field pinches (RFPs), and tandem mirrors. Conservative costing assumptions are made. The generic reactor is not a tokamak; rather, it is intended to emphasize what is common to all magnetic fusion rectors. The reactor uses a superconducting toroidal coil set to produce the dominant magnetic field. To this extent, it is not as good an approximation to systems such as the RFP in which the main field is produced by a plasma current. The main output of the study is the cost of electricity as a function of the weight and size of the fusion core - blanket, shield, structure, and coils. The model shows that a 1200-MW(e) power plant with a fusion core weight of about 10,000 tonnes should be competitive in the future with fission and fossil plants. Studies of the sensitivity of the model to variations in the assumptions show that this result is not sensitively dependent on any given assumption. Of particular importance is the result that a fusion reactor of this scale may be realized with only moderate advances in physics and technology capabilities.

  18. Magnet Design Considerations for Fusion Nuclear Science Facility

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Y. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Kessel, C. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); El-Guebaly, L. [Univ. of Wisconsin, Madison, WI (United States) Fusion Technology Institute; Titus, P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2016-06-01

    The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility that provides a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between the International Thermonuclear Experimental Reactor (ITER) and the demonstration power plant (DEMO). Compared with ITER, the FNSF is smaller in size but generates much higher magnetic field, i.e., 30 times higher neutron fluence with three orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5 T at the plasma center with a plasma major radius of 4.8 m and a minor radius of 1.2 m and a peak field of 15.5 T on the toroidal field (TF) coils for the FNSF. Both low-temperature superconductors (LTS) and high-temperature superconductors (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high-performance ternary restacked-rod process Nb3Sn strands for TF magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high-aspect-ratio rectangular CICC design are evaluated for FNSF magnets, but low-activation-jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. The material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.

  19. Diagnosing magnetized liner inertial fusion experiments on Z

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, S. B., E-mail: sbhanse@sandia.gov; Gomez, M. R.; Sefkow, A. B.; Slutz, S. A.; Sinars, D. B.; Hahn, K. D.; Harding, E. C.; Knapp, P. F.; Schmit, P. F.; Awe, T. J.; McBride, R. D.; Jennings, C. A.; Geissel, M.; Harvey-Thompson, A. J.; Peterson, K. J.; Rovang, D. C.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Hess, M. H. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); and others

    2015-05-15

    Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (∼10{sup 12} DD neutrons) from multi-keV deuterium plasmas inertially confined by slow (∼10 cm/μs), stable, cylindrical implosions. Effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10{sup 10}. Analysis of extensive power, imaging, and spectroscopic x-ray measurements provides a detailed picture of ∼3 keV temperatures, 0.3 g/cm{sup 3} densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  20. Mirror Fusion Test Facility: Superconducting magnet system cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    1977-07-01

    At the request of Victor Karpenko, Project manager for LLL`s Mirror Fusion Test Facility, EG&G has prepared this independent cost analysis for the proposed MFTF Superconducting Magnet System. The analysis has attempted to show sufficient detail to provide adequate definition for a basis of estimating costs.

  1. Materials studies for magnetic fusion energy applications at low temperatures, volume 12

    Science.gov (United States)

    Reed, R. P.; Tobler, R. L.

    1989-11-01

    The results are given of a research program to determine the properties of materials that may be used in cryogenic structures for the superconducting magnets of fusion energy power plants and prototypes. The program was developed jointly by the staffs of the National Institute of Standards and Technology and the Office of Fusion Energy of the Department of Energy. Research results for 1988 are presented in technical papers under four headings that reflect the main program areas: Structural Alloys; Welding; Technology Transfer; and United States-Japan Development of Test Standards. Objectives and research highlights are summarized in the introduction to each program area.

  2. Design of force-cooled conductors for large fusion magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dresner, L.; Lue, J.W.

    1977-01-01

    Conductors cooled by supercritical helium in forced convection are under active consideration for large toroidal fusion magnets. One of the central problems in designing such force cooled conductors is to maintain an adequate stability margin while keeping the pumping power tolerably low. A method has been developed for minimizing the pumping power for fixed stability by optimally choosing the matrix-to-superconductor and the metal-to-helium ratios. Such optimized conductors reduce pumping power requirements for fusion size magnets to acceptable limits. Furthermore, the mass flow and hence pumping losses can be varied through a magnet according to the local magnetic field and magnitude of desired stability margin. Force cooled conductors give flexibility in operation, permitting, for example, higher fields to be obtained than originally intended by lowering the bath temperature or increasing the pumping power or both. This flexibility is only available if the pumping power is low to begin with. Scaling laws for the pumping requirement and stability margin as functions of operating current density, number of strands and such physical parameters as stabilizer resistivity and critical current density, have been proved. Numerical examples will be given for design of conductors intended for use in large toroidal fusion magnet systems.

  3. Personnel Safety for Future Magnetic Fusion Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee Cadwallader

    2009-07-01

    The safety of personnel at existing fusion experiments is an important concern that requires diligence. Looking to the future, fusion experiments will continue to increase in power and operating time until steady state power plants are achieved; this causes increased concern for personnel safety. This paper addresses four important aspects of personnel safety in the present and extrapolates these aspects to future power plants. The four aspects are personnel exposure to ionizing radiation, chemicals, magnetic fields, and radiofrequency (RF) energy. Ionizing radiation safety is treated well for present and near-term experiments by the use of proven techniques from other nuclear endeavors. There is documentation that suggests decreasing the annual ionizing radiation exposure limits that have remained constant for several decades. Many chemicals are used in fusion research, for parts cleaning, as use as coolants, cooling water cleanliness control, lubrication, and other needs. In present fusion experiments, a typical chemical laboratory safety program, such as those instituted in most industrialized countries, is effective in protecting personnel from chemical exposures. As fusion facilities grow in complexity, the chemical safety program must transition from a laboratory scale to an industrial scale program that addresses chemical use in larger quantity. It is also noted that allowable chemical exposure concentrations for workers have decreased over time and, in some cases, now pose more stringent exposure limits than those for ionizing radiation. Allowable chemical exposure concentrations have been the fastest changing occupational exposure values in the last thirty years. The trend of more restrictive chemical exposure regulations is expected to continue into the future. Other issues of safety importance are magnetic field exposure and RF energy exposure. Magnetic field exposure limits are consensus values adopted as best practices for worker safety; a typical

  4. The ignition design space of magnetized target fusion

    Energy Technology Data Exchange (ETDEWEB)

    Lindemuth, Irvin R. [2490 North Grannen Road, Tucson, Arizona 85745 (United States)

    2015-12-15

    The simple magnetized target implosion model of Lindemuth and Kirkpatrick [Nucl. Fusion 23, 263 (1983)] has been extended to survey the potential parameter space in which three types of magnetized targets—cylindrical with axial magnetic field, cylindrical with azimuthal magnetic field, and spherical with azimuthal magnetic field—might achieve ignition and produce large gain at achievable radial convergence ratios. The model has been used to compute the dynamic, time-dependent behavior of many initial parameter sets that have been based upon projected ignition conditions using the quasi-adiabatic and quasi-flux-conserving properties of magnetized target implosions. The time-dependent calculations have shown that energy gains greater than 30 can potentially be achieved for each type of target. By example, it is shown that high gain may be obtained at extremely low convergence ratios, e.g., less than 15, for appropriate initial conditions. It is also shown that reaching the ignition condition, i.e., when fusion deposition rates equal total loss rates, does not necessarily lead to high gain and high fuel burn-up. At the lower densities whereby fusion temperatures can be reached in magnetized targets, the fusion burn rate may be only comparable with the hydrodynamic heating/cooling rates. On the other hand, when the fusion burn rates significantly exceed the hydrodynamic rates, the calculations show a characteristic rapid increase in temperature due to alpha particle deposition with a subsequent increased burn rate and high gain. A major result of this paper is that each type of target operates in a different initial density-energy-velocity range. The results of this paper provide initial target plasma parameters and driver parameters that can be used to guide plasma formation and driver development for magnetized targets. The results indicate that plasmas for spherical, cylindrical with azimuthal field, and cylindrical with axial field targets must have an initial

  5. Magnetic charge lattices, moduli spaces and fusion rules

    Energy Technology Data Exchange (ETDEWEB)

    Kampmeijer, L. [Institute for Theoretical Physics, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)], E-mail: leo.kampmeijer@uva.nl; Slingerland, J.K. [Dublin Institute for Advanced Studies, School for Theoretical Physics, 10 Burlington Rd, Dublin (Ireland)], E-mail: slingerland@stp.dias.ie; Schroers, B.J. [Department of Mathematics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS (United Kingdom)], E-mail: bernd@ma.hw.ac.uk; Bais, F.A. [Institute for Theoretical Physics, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)], E-mail: bais@science.uva.nl

    2009-01-01

    We analyze the labelling and fusion properties of magnetic charge sectors consisting of smooth BPS monopoles in Yang-Mills-Higgs theory with arbitrary gauge group G spontaneously broken to a subgroup H. The magnetic charges are restricted by a generalized Dirac quantization condition and by an inequality due to Murray. Geometrically, the set of allowed charges is a solid cone in the coroot lattice of G, which we call the Murray cone. We argue that magnetic charge sectors correspond to points in this cone divided by the Weyl group of H so that magnetic charge sectors are labelled by dominant integral weights of the dual group H*. We define generators of the Murray cone modulo Weyl group, and interpret the monopoles in the associated magnetic charge sectors as basic; monopoles in sectors with decomposable charges are interpreted as composite configurations. This interpretation is supported by the dimensionality of the moduli spaces associated to the magnetic charges and by classical fusion properties for smooth monopoles in particular cases. Throughout the paper we compare our findings with corresponding results for singular monopoles recently obtained by Kapustin and Witten.

  6. Measurements of fusion neutrons from Magnetized Liner Inertial Fusion Experiments on the Z accelerator

    Science.gov (United States)

    Hahn, K. D.; Chandler, G. A.; Ruiz, C. L.; Gomez, M. R.; Slutz, S. A.; Sefkow, A. B.; Sinars, D. B.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Harding, E. C.; Awe, T. J.; Torres, J. A.; Jones, B.; Bur, J. A.; Cooper, G. W.; Styron, J. D.; Glebov, V. Yu.

    2015-11-01

    Strong evidence of thermonuclear neutron production has been observed during Magnetized Liner Inertial Fusion (MagLIF) experiments on the Z accelerator. So far, these experiments have utilized deuterium fuel and produced primary DD fusion neutron yields up to 2e12 with electron and ion stagnation temperatures in the 2-3 keV range. We present MagLIF neutron measurements and compare to other data and implosion simulations. In addition to primary DD and secondary DT yields and ion temperatures, other complex physics regarding the degree of fuel magnetization and liner density are elucidated by the neutron measurements. Neutron diagnostic development for deuterium and future deuterium-tritium fuel experiments are also discussed. Sandia is sponsored by the U.S. DOE's NNSA under contract DE-AC04-94AL85000.

  7. Magnetic stochasticity in magnetically confined fusion plasmas chaos of field lines and charged particle dynamics

    CERN Document Server

    Abdullaev, Sadrilla

    2014-01-01

    This is the first book to systematically consider the modern aspects of chaotic dynamics of magnetic field lines and charged particles in magnetically confined fusion plasmas.  The analytical models describing the generic features of equilibrium magnetic fields and  magnetic perturbations in modern fusion devices are presented. It describes mathematical and physical aspects of onset of chaos, generic properties of the structure of stochastic magnetic fields, transport of charged particles in tokamaks induced by magnetic perturbations, new aspects of particle turbulent transport, etc. The presentation is based on the classical and new unique mathematical tools of Hamiltonian dynamics, like the action--angle formalism, classical perturbation theory, canonical transformations of variables, symplectic mappings, the Poincaré-Melnikov integrals. They are extensively used for analytical studies as well as for numerical simulations of magnetic field lines, particle dynamics, their spatial structures and  statisti...

  8. The Quest for Fusion at the National Ignition Facility

    Science.gov (United States)

    Hartouni, Edward

    2017-01-01

    Arthur Eddington speculated in 1920 on the internal constitution of stars and described the possibility of nuclear fusion based on the then new results from special relativity and measurements of light nuclei masses. By 1929 Atkinson and Houtermans worked out the calculations for nuclear fusion in stars and initiating nuclear astrophysics. All of these sciences were pressed into service during the World War II, and the applications developed, particularly under the auspices of the Manhattan Project provided both weapons with which to wage and win that conflict, but also the possibilities to harness these applications of the nuclear processes of fission and fusion for peaceful purposes. 32 years after Eddington's speculation the United States demonstrated the application of fusion in a famous nuclear weapons test. In the following years many ideas for producing ``controlled'' fusion through inertial confinement were pursued. The invention of the laser opened up new avenues which have culminated in the National Ignition Facility, NIF. I will attempt to cover the ground between Eddington, through the Manhattan Project and provide a current status of this quest at NIF. LLNL-ABS-704367-DRAFT. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  9. Image fusion for dynamic contrast enhanced magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Leach Martin O

    2004-10-01

    Full Text Available Abstract Background Multivariate imaging techniques such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI have been shown to provide valuable information for medical diagnosis. Even though these techniques provide new information, integrating and evaluating the much wider range of information is a challenging task for the human observer. This task may be assisted with the use of image fusion algorithms. Methods In this paper, image fusion based on Kernel Principal Component Analysis (KPCA is proposed for the first time. It is demonstrated that a priori knowledge about the data domain can be easily incorporated into the parametrisation of the KPCA, leading to task-oriented visualisations of the multivariate data. The results of the fusion process are compared with those of the well-known and established standard linear Principal Component Analysis (PCA by means of temporal sequences of 3D MRI volumes from six patients who took part in a breast cancer screening study. Results The PCA and KPCA algorithms are able to integrate information from a sequence of MRI volumes into informative gray value or colour images. By incorporating a priori knowledge, the fusion process can be automated and optimised in order to visualise suspicious lesions with high contrast to normal tissue. Conclusion Our machine learning based image fusion approach maps the full signal space of a temporal DCE-MRI sequence to a single meaningful visualisation with good tissue/lesion contrast and thus supports the radiologist during manual image evaluation.

  10. The theory of the failure of magnetic fusion

    Science.gov (United States)

    Zakharov, Leonid E.

    2007-11-01

    In the physics of the 20th century, fusion represents an extraordinary failure which eroded expectations of society on an ``unexhaustible'' energy source. The question is if these 50 years of research did really prove that fusion will be forever a ``carrot'' on a stick and always 35 years from its implementation. When a person is asking fusion people why this program is full of broken promises, he (besides conventional complaints on the lack of funding) is typically getting the answer that the problem itself is the most difficult one that physics ever faced. In the FSU, such characterizations were done as early as in the 60s by Lev Artsimovich, the leader in the field. This view is only partially applicable in the 21st century. Since the times of Artsimovich, fusion, as a ``difficult'' problem, has been converted into the ``complicated'' one. The presented theory makes a clear distinction between these two kinds of problems, which require significantly different management approaches, and explains the current stagnation in magnetic fusion by the lack of understanding this crucial difference.

  11. Magnetized Target Fusion Propulsion: Plasma Injectors for MTF Guns

    Science.gov (United States)

    Griffin, Steven T.

    2003-01-01

    To achieve increased payload size and decreased trip time for interplanetary travel, a low mass, high specific impulse, high thrust propulsion system is required. This suggests the need for research into fusion as a source of power and high temperature plasma. The plasma would be deflected by magnetic fields to provide thrust. Magnetized Target Fusion (MTF) research consists of several related investigations into these topics. These include the orientation and timing of the plasma guns and the convergence and interface development of the "pusher" plasma. Computer simulations of the gun as it relates to plasma initiation and repeatability are under investigation. One of the items under development is the plasma injector. This is a surface breakdown driven plasma generator designed to function at very low pressures. The performance, operating conditions and limitations of these injectors need to be determined.

  12. Ignition and Inertial Confinement Fusion at The National Ignition Facility

    Science.gov (United States)

    Moses, Edward I.

    2016-10-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and for studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF is now conducting experiments to commission the laser drive, the hohlraum and the capsule and to develop the infrastructure needed to begin the first ignition experiments in FY 2010. Demonstration of ignition and thermonuclear bum in the laboratory is a major NIF goal. NIF will achieve this by concentrating the energy from the 192 beams into a mm3-sized target and igniting a deuterium-tritium mix, liberating more energy than is required to initiate the fusion reaction. NIP's ignition program is a national effort managed via the National Ignition Campaign (NIC). The NIC has two major goals: execution of DT ignition experiments starting in FY20l0 with the goal of demonstrating ignition and a reliable, repeatable ignition platform by the conclusion of the NIC at the end of FY2012. The NIC will also develop the infrastructure and the processes required to operate NIF as a national user facility. The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on laser fusion as a viable energy option. A laser fusion-based energy concept that builds on NIF, known as LIFE (Laser Inertial Fusion Energy), is currently under development. LIFE is inherently safe and can provide a global carbon-free energy generation solution in the 21st century. This paper describes recent progress on NIF, NIC, and the LIFE concept.

  13. Failure modes and effects analysis of fusion magnet systems

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, M; Kazimi, M S; Siu, N O; Thome, R J

    1988-12-01

    A failure modes and consequence analysis of fusion magnet system is an important contributor towards enhancing the design by improving the reliability and reducing the risk associated with the operation of magnet systems. In the first part of this study, a failure mode analysis of a superconducting magnet system is performed. Building on the functional breakdown and the fault tree analysis of the Toroidal Field (TF) coils of the Next European Torus (NET), several subsystem levels are added and an overview of potential sources of failures in a magnet system is provided. The failure analysis is extended to the Poloidal Field (PF) magnet system. Furthermore, an extensive analysis of interactions within the fusion device caused by the operation of the PF magnets is presented in the form of an Interaction Matrix. A number of these interactions may have significant consequences for the TF magnet system particularly interactions triggered by electrical failures in the PF magnet system. In the second part of this study, two basic categories of electrical failures in the PF magnet system are examined: short circuits between the terminals of external PF coils, and faults with a constant voltage applied at external PF coil terminals. An electromagnetic model of the Compact Ignition Tokamak (CIT) is used to examine the mechanical load conditions for the PF and the TF coils resulting from these fault scenarios. It is found that shorts do not pose large threats to the PF coils. Also, the type of plasma disruption has little impact on the net forces on the PF and the TF coils. 39 refs., 30 figs., 12 tabs.

  14. Multi sensor national cyber security data fusion

    CSIR Research Space (South Africa)

    Swart, I

    2015-03-01

    Full Text Available information security posture and to improve on it. The potential attack surface of a nation is extremely large however and no single source of cyber security data provides all the required information to accurately describe the cyber security readiness of a...

  15. A semi-analytic model of magnetized liner inertial fusion

    Science.gov (United States)

    McBride, Ryan D.; Slutz, Stephen A.

    2015-05-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  16. A semi-analytic model of magnetized liner inertial fusion

    Energy Technology Data Exchange (ETDEWEB)

    McBride, Ryan D.; Slutz, Stephen A. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2015-05-15

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  17. Semi-analytic modeling and simulation of magnetized liner inertial fusion

    Science.gov (United States)

    McBride, R. D.; Slutz, S. A.; Hansen, S. B.

    2013-10-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) pre-heat of the fuel; (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, and internal magnetic pressure and heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) deuterium-deuterium and deuterium-tritium primary fusion reactions; and (9) magnetized alpha-particle heating. We will first show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper. We will then use this model to illustrate the MagLIF parameter space, energetics, and efficiencies, and to show the experimental challenges that we will likely be facing as we begin testing MagLIF using the infrastructure presently available at the Z facility. Finally, we will demonstrate how this scenario could likely change as various facility upgrades are made over the next three to five years and beyond. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  18. Magnet safety and reliability in magnetic fusion energy systems. A summary report

    Energy Technology Data Exchange (ETDEWEB)

    Powell, J; Hsieh, D; Lehner, J; Reich, M; Yu, W Y

    1977-02-01

    The results of a two year study on magnet safety as it applies to Magnetic Fusion Energy Reactors and influences current program planning and experimental magnet design are presented in this summary report. Existing experience with superconducting magnet design and operation has been reviewed with the help of many active workers in this field and related to general reactor safety studies and techniques using the vast body of work generated in fission reactor safety programs as an illustrative reference base. A principal conclusion is that the inclusion of safety planning and design as a program component even at this early stage in Magnetic Fusion Reactor Development will save a great deal of money, time and design readjustment in the total thirty year program now envisaged.

  19. Preliminary results from the first integrated Magnetized Liner Inertial Fusion (MagLIF) experiments on the Z accelerator

    Science.gov (United States)

    Gomez, M. R.; Slutz, S. A.; Sefkow, A. B.; Harvey-Thompson, A. J.; Awe, T. J.; Cuneo, M. E.; Geissel, M.; Herrmann, M.; Jennings, C.; Lamppa, D.; Martin, M.; McBride, R. D.; Rovang, D. C.; Sinars, D.; Smith, I. C.

    2013-10-01

    Sandia National Laboratories' Z Machine provides a drive current of up to 27 MA with 100 ns risetime to a magnetically-driven load. Magnetized Liner Inertial Fusion (MagLIF) is the main focus of the inertial confinement fusion program on Z. The MagLIF concept uses an imploding metallic cylindrical liner to compress magnetized, pre-heated fusion fuel. Simulations indicate that fusion yields on the order of 100 kJ (5e16 DT neutrons) are achievable with a drive current of 27 MA in 100 ns, a laser preheat of 8 kJ in 8 ns, an applied axial B-field of 30 T, and deuterium-tritium fusion fuel. The first fully integrated MagLIF experiments are scheduled to be conducted on Z late summer 2013. These tests will utilize a drive current of 16 MA, a laser preheat of 2 kJ in 2 ns, an applied B-field of 10 T, and deuterium fuel. With these reduced parameters, simulations predict yields greater than 1e10 DD neutrons. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  20. Final report on the Magnetized Target Fusion Collaboration

    Energy Technology Data Exchange (ETDEWEB)

    John Slough

    2009-09-08

    Nuclear fusion has the potential to satisfy the prodigious power that the world will demand in the future, but it has yet to be harnessed as a practical energy source. The entry of fusion as a viable, competitive source of power has been stymied by the challenge of finding an economical way to provide for the confinement and heating of the plasma fuel. It is the contention here that a simpler path to fusion can be achieved by creating fusion conditions in a different regime at small scale (~ a few cm). One such program now under study, referred to as Magnetized Target Fusion (MTF), is directed at obtaining fusion in this high energy density regime by rapidly compressing a compact toroidal plasmoid commonly referred to as a Field Reversed Configuration (FRC). To make fusion practical at this smaller scale, an efficient method for compressing the FRC to fusion gain conditions is required. In one variant of MTF a conducting metal shell is imploded electrically. This radially compresses and heats the FRC plasmoid to fusion conditions. The closed magnetic field in the target plasmoid suppresses the thermal transport to the confining shell, thus lowering the imploding power needed to compress the target. The undertaking to be described in this proposal is to provide a suitable target FRC, as well as a simple and robust method for inserting and stopping the FRC within the imploding liner. The timescale for testing and development can be rapidly accelerated by taking advantage of a new facility funded by the Department of Energy. At this facility, two inductive plasma accelerators (IPA) were constructed and tested. Recent experiments with these IPAs have demonstrated the ability to rapidly form, accelerate and merge two hypervelocity FRCs into a compression chamber. The resultant FRC that was formed was hot (T&ion ~ 400 eV), stationary, and stable with a configuration lifetime several times that necessary for the MTF liner experiments. The accelerator length was less than

  1. Prospects for x-ray polarimetry measurements of magnetic fields in magnetized liner inertial fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Lynn, Alan G., E-mail: lynn@ece.unm.edu; Gilmore, Mark [Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2014-11-15

    Magnetized Liner Inertial Fusion (MagLIF) experiments, where a metal liner is imploded to compress a magnetized seed plasma may generate peak magnetic fields ∼10{sup 4} T (100 Megagauss) over small volumes (∼10{sup −10}m{sup 3}) at high plasma densities (∼10{sup 28}m{sup −3}) on 100 ns time scales. Such conditions are extremely challenging to diagnose. We discuss the possibility of, and issues involved in, using polarimetry techniques at x-ray wavelengths to measure magnetic fields under these extreme conditions.

  2. Prospects for x-ray polarimetry measurements of magnetic fields in magnetized liner inertial fusion plasmas

    Science.gov (United States)

    Lynn, Alan G.; Gilmore, Mark

    2014-11-01

    Magnetized Liner Inertial Fusion (MagLIF) experiments, where a metal liner is imploded to compress a magnetized seed plasma may generate peak magnetic fields ˜104 T (100 Megagauss) over small volumes (˜10-10m3) at high plasma densities (˜1028m-3) on 100 ns time scales. Such conditions are extremely challenging to diagnose. We discuss the possibility of, and issues involved in, using polarimetry techniques at x-ray wavelengths to measure magnetic fields under these extreme conditions.

  3. Prospects for x-ray polarimetry measurements of magnetic fields in magnetized liner inertial fusion plasmas.

    Science.gov (United States)

    Lynn, Alan G; Gilmore, Mark

    2014-11-01

    Magnetized Liner Inertial Fusion (MagLIF) experiments, where a metal liner is imploded to compress a magnetized seed plasma may generate peak magnetic fields ∼10(4) T (100 Megagauss) over small volumes (∼10(-10)m(3)) at high plasma densities (∼10(28)m(-3)) on 100 ns time scales. Such conditions are extremely challenging to diagnose. We discuss the possibility of, and issues involved in, using polarimetry techniques at x-ray wavelengths to measure magnetic fields under these extreme conditions.

  4. Understanding of Edge Plasmas in Magnetic Fusion Energy Devices

    Energy Technology Data Exchange (ETDEWEB)

    Rognlien, T

    2004-11-01

    A limited overview is given of the theoretical understanding of edge plasmas in fusion devices. This plasma occupies the thin region between the hot core plasma and material walls in magnetically confinement configurations. The region is often formed by a change in magnetic topology from close magnetic field lines (i.e., the core region) and open field lines that contact material surfaces (i.e., the scrape-off layer [SOL]), with the most common example being magnetically diverted tokamaks. The physics of this region is determined by the interaction of plasma with neutral gas in the presence of plasma turbulence, with impurity radiation being an important component. Recent advances in modeling strong, intermittent micro-turbulent edge-plasma transport is given, and the closely coupled self-consistent evolution of the edge-plasma profiles in tokamaks. In addition, selected new results are given for the characterization of edge-plasmas behavior in the areas of edge-pedestal relaxation and SOL transport via Edge-Localize Modes (ELMs), impurity formation including dust, and magnetic field-line stochasticity in tokamaks.

  5. Fusion ignition via a magnetically-assisted fast ignition approach

    CERN Document Server

    Wang, W -M; Sheng, Z -M; Li, Y T; Zhang, J

    2016-01-01

    Significant progress has been made towards laser-driven fusion ignition via different schemes, including direct and indirect central ignition, fast ignition, shock ignition, and impact ignition schemes. However, to reach ignition conditions, there are still various technical and physical challenges to be solved for all these schemes. Here, our multi-dimensional integrated simulation shows that the fast-ignition conditions could be achieved when two 2.8 petawatt heating laser pulses counter-propagate along a 3.5 kilotesla external magnetic field. Within a period of 5 picoseconds, the laser pulses heat a nuclear fuel to reach the ignition conditions. Furthermore, we present the parameter windows of lasers and magnetic fields required for ignition for experimental test.

  6. Optimal Liner Material for Near Term Magnetized Liner Fusion Experiments

    Science.gov (United States)

    Slutz, Stephen

    2012-10-01

    Substantial fusion yields are predicted with existing pulsed power machines driving cylindrical liner implosions with preheated and magnetized deuterium-tritium [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)]. Experiments are planned using the Z accelerator to drive these implosions. However, the peak current, the laser heating energy, and the applied magnetic field will be less than optimal. We present simulations which show, that under these conditions, the yield can be improved significantly by decreasing the density of the liner material, e.g. Lithium substituted for Beryllium. Furthermore, the simulations show that decreasing the liner density allows the use of very low aspect ratio (R/δR) liners, while still obtaining interesting yields. Low aspect ratio liners should be more robust to the Rayleigh-Taylor instability.

  7. Comparison between initial Magnetized Liner Inertial Fusion experiments and integrated simulations

    Science.gov (United States)

    Sefkow, A. B.; Gomez, M. R.; Geissel, M.; Hahn, K. D.; Hansen, S. B.; Harding, E. C.; Peterson, K. J.; Slutz, S. A.; Koning, J. M.; Marinak, M. M.

    2014-10-01

    The Magnetized Liner Inertial Fusion (MagLIF) approach to ICF has obtained thermonuclear fusion yields using the Z facility. Integrated magnetohydrodynamic simulations provided the design for the first neutron-producing experiments using capabilities that presently exist, and the initial experiments measured stagnation radii rstag < 75 μm, temperatures around 3 keV, and isotropic neutron yields up to YnDD = 2 ×1012 from imploded liners reaching peak velocities around 70 km/s over an implosion time of about 60 ns. We present comparisons between the experimental observables and post-shot degraded integrated simulations. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  8. Aspects of safety and reliability for fusion magnet systems first annual report

    Energy Technology Data Exchange (ETDEWEB)

    Powell, J. (ed.)

    1976-01-15

    General systems aspects of fusion magnet safety are examined first, followed by specific detailed analyses covering structural, thermal, electrical, and other aspects of fusion magnet safety. The design examples chosen for analysis are illustrative and are not intended to be definitive, since fusion magnet designs are rapidly evolving. Included is a comprehensive collection of design and operating data relating to the safety of existing superconducting magnet systems. The remainder of the overview lists the main conclusions developed from the work to date. These should be regarded as initial steps. Since this study has concentrated on examining potential safety concerns, it may tend to overemphasize the problems of fusion magnets. In fact, many aspects of fusion magnets are well developed and are consistent with good safety practice. A short summary of the findings of this study is given.

  9. Numerical studies of liners for magnetized target fusion (MTF)

    CERN Document Server

    Faehl, R J; Sheehey, P T; Lindemuth, I R

    1999-01-01

    Summary form only given. Magnetized target fusion (MTF) requires the fast compression of hot, dense plasmas by a conducting liner. We have used two-dimensional MHD calculations to study the electromagnetic implosion of metallic liners driven by realistic current waveforms. Parametric studies have indicated that the liner should reach velocities of 3-20 km/s, depending on the magnetic field configuration, and reach convergence ratios (initial radius divided by final radius) of at least 10. These parameters are accessible with large capacitor bank power supplies such as SHIVA or ATLAS, or with magnetic flux compression generators. One issue with the high currents that are required to implode the liner is that Ohmic heating will melt or vaporize the outer part of the liner. Calculations have shown that this is a realistic concern. We are currently addressing questions of liner instability and flux diffusion under MTF conditions. Another issue is that the magnetic fields needed to inhibit thermal losses to the wa...

  10. Generation and compression of a target plasma for magnetized target fusion

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, R.C.; Lindemuth, I.R.; Sheehey, P.T. [and others

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Magnetized target fusion (MTF) is intermediate between the two very different approaches to fusion: inertial and magnetic confinement fusion (ICF and MCF). Results from collaboration with a Russian MTF team on their MAGO experiments suggest they have a target plasma suitable for compression to provide an MTF proof of principle. This LDRD project had tow main objectives: first, to provide a computational basis for experimental investigation of an alternative MTF plasma, and second to explore the physics and computational needs for a continuing program. Secondary objectives included analytic and computational support for MTF experiments. The first objective was fulfilled. The second main objective has several facets to be described in the body of this report. Finally, the authors have developed tools for analyzing data collected on the MAGO a nd LDRD experiments, and have tested them on limited MAGO data.

  11. The influence of combined magnetic field on the fusion of plant protoplasts.

    Science.gov (United States)

    Nedukha, O; Kordyum, E; Bogatina, N; Sobol, M; Vorobyeva, T; Ovcharenko, Yu

    2007-07-01

    The study of the influence of weak, alternating magnetic field, which was adjusted to the cyclotron frequency of Ca2+ and K+ ions, on the fusion of tobacco and soya protoplasts was carried out using the extra apparatus with ferromagnetic shield. An increase in the frequency of protoplasts fusion in 2-3 times and participation of calcium ions in the induction of protoplast fusion in weak alternating magnetic field have been established.

  12. Magnetized Inertial Fusion (MIF) Research at the Shiva Star Facility

    Science.gov (United States)

    Degnan, James; Grabowski, C.; Domonkos, M.; Ruden, E. L.; Amdahl, D. J.; White, W. M.; Frese, M. H.; Frese, S. D.; Wurden, G. A.; Weber, T. E.

    2015-11-01

    The AFRL Shiva Star capacitor bank (1300 μF, up to 120 kV) used typically at 4 to 5 MJ stored energy, 10 to 15 MA current, 10 μs current rise time, has been used to drive metal shell (solid liner) implosions for compression of axial magnetic fields to multi-megagauss levels, suitable for compressing magnetized plasmas to MIF conditions. MIF approaches use magnetic field to reduce thermal conduction relative to inertial confinement fusion (ICF). MIF substantially reduces required implosion speed and convergence. Using profiled thickness liner enables large electrode apertures and field-reversed configuration (FRC) injection. Using a longer capture region, FRC trapped flux lifetime was made comparable to implosion time and an integrated compression test was conducted. The FRC was radially compressed a factor of ten, to 100x density >1018 cm-3 (a world FRC record), but temperatures were only 300-400 eV, compared to intended several keV. Compression to megabar pressures was inferred by the observed liner rebound, but the heating rate during the first half of the compression was less than the normal FRC decay rate. Principal diagnostics were soft x-ray imaging, soft x-ray diodes, and neutron measurements. This work has been supported by DOE-OFES.

  13. Soft X-ray measurements in magnetic fusion plasma physics

    Science.gov (United States)

    Botrugno, A.; Gabellieri, L.; Mazon, D.; Pacella, D.; Romano, A.

    2010-11-01

    Soft X-ray diagnostic systems and their successful application in the field of magnetic fusion plasma physics are discussed. Radiation with wavelength in the region of Soft X-Ray (1-30 keV) is largely produced by high temperature plasmas, carrying important information on many processes during a plasma discharge. Soft X-ray diagnostics are largely used in various fusion devices all over the world. These diagnostic systems are able to obtain information on electron temperature, electron density, impurity transport, Magneto Hydro Dynamic instabilities. We will discuss the SXR diagnostic installed on FTU in Frascati (Italy) and on Tore Supra in Cadarache (France), with special emphasis on diagnostic performances. Moreover, we will discuss the two different inversion methods for tomographic reconstruction used in Frascati and in Cadarache, the first one is relied on a guessed topology of iso-emissivity surfaces, the second one on regularization techniques, like minimum Fisher or maximum entropy. Finally, a new and very fast 2D imaging system with energy discrimination and high time resolution will be summarized as an alternative approach of SXR detection system.

  14. Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stratton, B. C.; Biter, M.; Hill, K. W.; Hillis, D. L.; Hogan, J. T.

    2007-07-18

    Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

  15. Vibration of fusion reactor components with magnetic damping

    Energy Technology Data Exchange (ETDEWEB)

    D’Amico, Gabriele; Portone, Alfredo [Fusion for Energy – Torres Diagonal Litoral B3 – c/Josep Plá n.2, Barcelona (Spain); Rubinacci, Guglielmo [Department of Electrical Eng. and Information Technologies, Università di Napoli Federico II, Via Claudio, 21, 80125 Napoli (Italy); Testoni, Pietro, E-mail: pietro.testoni@f4e.europa.eu [Fusion for Energy – Torres Diagonal Litoral B3 – c/Josep Plá n.2, Barcelona (Spain)

    2016-11-01

    The aim of this paper is to assess the importance of the magnetic damping in the dynamic response of the main plasma facing components of fusion machines, under the strong Lorentz forces due to Vertical Displacement Events. The additional eddy currents due to the vibration of the conducting structures give rise to volume loads acting as damping forces, a kind of viscous damping, being these additional loads proportional to the vibration speed. This effect could play an important role when assessing, for instance, the inertial loads associated to VV movements in case of VDEs. In this paper, we present the results of a novel numerical formulation, in which the field equations are solved by adopting a very effective fully 3D integral formulation, not limited to the analysis of thin shell structures, as already successfully done in several approaches previously published.

  16. The materials production and processing facility at the Spanish National Centre for fusion technologies (TechnoFusion)

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, A., E-mail: rpp@fis.uc3m.es [Departamento de Fisica, UC3M, Avda de la Universidad 30, 28911 Leganes, Madrid (Spain); Monge, M.A.; Pareja, R. [Departamento de Fisica, UC3M, Avda de la Universidad 30, 28911 Leganes, Madrid (Spain); Hernandez, M.T. [LNF-CIEMAT, Avda, Complutense, 22, 28040 Madrid (Spain); Jimenez-Rey, D. [CMAM, UAM, C/Faraday 3, 28049, Madrid (Spain); Roman, R.; Gonzalez, M.; Garcia-Cortes, I. [LNF-CIEMAT, Avda, Complutense, 22, 28040 Madrid (Spain); Perlado, M. [IFN, ETSII, UPM, C/Jose Gutierrez Abascal, 2, 28006 Madrid (Spain); Ibarra, A. [LNF-CIEMAT, Avda, Complutense, 22, 28040 Madrid (Spain)

    2011-10-15

    In response to the urgent request from the EU Fusion Program, a new facility (TechnoFusion) for research and development of fusion materials has been planned with support from the Regional Government of Madrid and the Ministry of Science and Innovation of Spain. TechnoFusion, the National Centre for Fusion Technologies, aims screening different technologies relevant for ITER and DEMO environments while promoting the contribution of international companies and research groups into the Fusion Programme. For this purpose, the centre will be provided with a large number of unique facilities for the manufacture, testing (a triple-beam multi-ion irradiation, a plasma-wall interaction device, a remote handling for under ionizing radiation testing) and analysis of critical fusion materials. Particularly, the objectives, semi-industrial scale capabilities and present status of the TechnoFusion Materials Production and Processing (MPP) facility are presented. Previous studies revealed that the MPP facility will be a very promising infrastructure for the development of new materials and prototypes demanded by the fusion technology and therefore some of them will be here briefly summarized.

  17. Demonstration of thermonuclear conditions in magnetized liner inertial fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M. R.; Slutz, S. A.; Sefkow, A. B.; Hahn, K. D.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Ruiz, C. L.; Sinars, D. B.; Harding, E. C.; Jennings, C. A.; Awe, T. J.; Geissel, M.; Rovang, D. C.; Smith, I. C.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Harvey-Thompson, A. J.; Hess, M. H. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); and others

    2015-05-15

    The magnetized liner inertial fusion concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] utilizes a magnetic field and laser heating to relax the pressure requirements of inertial confinement fusion. The first experiments to test the concept [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] were conducted utilizing the 19 MA, 100 ns Z machine, the 2.5 kJ, 1 TW Z Beamlet laser, and the 10 T Applied B-field on Z system. Despite an estimated implosion velocity of only 70 km/s in these experiments, electron and ion temperatures at stagnation were as high as 3 keV, and thermonuclear deuterium-deuterium neutron yields up to 2 × 10{sup 12} have been produced. X-ray emission from the fuel at stagnation had widths ranging from 50 to 110 μm over a roughly 80% of the axial extent of the target (6–8 mm) and lasted approximately 2 ns. X-ray yields from these experiments are consistent with a stagnation density of the hot fuel equal to 0.2–0.4 g/cm{sup 3}. In these experiments, up to 5 × 10{sup 10} secondary deuterium-tritium neutrons were produced. Given that the areal density of the plasma was approximately 1–2 mg/cm{sup 2}, this indicates the stagnation plasma was significantly magnetized, which is consistent with the anisotropy observed in the deuterium-tritium neutron spectra. Control experiments where the laser and/or magnetic field were not utilized failed to produce stagnation temperatures greater than 1 keV and primary deuterium-deuterium yields greater than 10{sup 10}. An additional control experiment where the fuel contained a sufficient dopant fraction to substantially increase radiative losses also failed to produce a relevant stagnation temperature. The results of these experiments are consistent with a thermonuclear neutron source.

  18. Exploring magnetized liner inertial fusion with a semi-analytic model

    CERN Document Server

    McBride, R D; Vesey, R A; Gomez, M R; Sefkow, A B; Hansen, S B; Knapp, P F; Schmit, P F; Geissel, M; Harvey-Thompson, A J; Jennings, C A; Harding, E C; Awe, T J; Rovang, D C; Hahn, K D; Martin, M R; Cochrane, K R; Peterson, K J; Rochau, G A; Porter, J L; Stygar, W A; Campbell, E M; Nakhleh, C W; Herrmann, M C; Cuneo, M E; Sinars, D B

    2016-01-01

    In this paper, we explore magnetized liner inertial fusion (MagLIF) [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] using a semi-analytic model [R. D. McBride and S. A. Slutz, Phys. Plasmas 22, 052708 (2015)]. Specifically, we present simulation results from this model that: (a) illustrate the parameter space, energetics, and overall system efficiencies of MagLIF; (b) demonstrate the dependence of radiative loss rates on the radial fraction of the fuel that is preheated; (c) explore some of the recent experimental results of the MagLIF program at Sandia National Laboratories [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)]; (d) highlight the experimental challenges presently facing the MagLIF program; and (e) demonstrate how increases to the preheat energy, fuel density, axial magnetic field, and drive current could affect future MagLIF performance.

  19. Exploring magnetized liner inertial fusion with a semi-analytic model

    Energy Technology Data Exchange (ETDEWEB)

    McBride, R. D.; Slutz, S. A.; Vesey, R. A.; Gomez, M. R.; Sefkow, A. B.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Geissel, M.; Harvey-Thompson, A. J.; Jennings, C. A.; Harding, E. C.; Awe, T. J.; Rovang, D. C.; Hahn, K. D.; Martin, M. R.; Cochrane, K. R.; Peterson, K. J.; Rochau, G. A.; Porter, J. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); and others

    2016-01-15

    In this paper, we explore magnetized liner inertial fusion (MagLIF) [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] using a semi-analytic model [R. D. McBride and S. A. Slutz, Phys. Plasmas 22, 052708 (2015)]. Specifically, we present simulation results from this model that: (a) illustrate the parameter space, energetics, and overall system efficiencies of MagLIF; (b) demonstrate the dependence of radiative loss rates on the radial fraction of the fuel that is preheated; (c) explore some of the recent experimental results of the MagLIF program at Sandia National Laboratories [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)]; (d) highlight the experimental challenges presently facing the MagLIF program; and (e) demonstrate how increases to the preheat energy, fuel density, axial magnetic field, and drive current could affect future MagLIF performance.

  20. Report of the Fusion Energy Sciences Advisory Committee. Panel on Integrated Simulation and Optimization of Magnetic Fusion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dahlburg, Jill [General Atomics, San Diego, CA (United States); Corones, James [Krell Inst., Ames, IA (United States); Batchelor, Donald [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bramley, Randall [Indiana Univ., Bloomington, IN (United States); Greenwald, Martin [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Jardin, Stephen [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Krasheninnikov, Sergei [Univ. of California, San Diego, CA (United States); Laub, Alan [Univ. of California, Davis, CA (United States); Leboeuf, Jean-Noel [Univ. of California, Los Angeles, CA (United States); Lindl, John [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lokke, William [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rosenbluth, Marshall [Univ. of California, San Diego, CA (United States); Ross, David [Univ. of Texas, Austin, TX (United States); Schnack, Dalton [Science Applications International Corporation, Oak Ridge, TN (United States)

    2002-11-01

    Fusion is potentially an inexhaustible energy source whose exploitation requires a basic understanding of high-temperature plasmas. The development of a science-based predictive capability for fusion-relevant plasmas is a challenge central to fusion energy science, in which numerical modeling has played a vital role for more than four decades. A combination of the very wide range in temporal and spatial scales, extreme anisotropy, the importance of geometric detail, and the requirement of causality which makes it impossible to parallelize over time, makes this problem one of the most challenging in computational physics. Sophisticated computational models are under development for many individual features of magnetically confined plasmas and increases in the scope and reliability of feasible simulations have been enabled by increased scientific understanding and improvements in computer technology. However, full predictive modeling of fusion plasmas will require qualitative improvements and innovations to enable cross coupling of a wider variety of physical processes and to allow solution over a larger range of space and time scales. The exponential growth of computer speed, coupled with the high cost of large-scale experimental facilities, makes an integrated fusion simulation initiative a timely and cost-effective opportunity. Worldwide progress in laboratory fusion experiments provides the basis for a recent FESAC recommendation to proceed with a burning plasma experiment (see FESAC Review of Burning Plasma Physics Report, September 2001). Such an experiment, at the frontier of the physics of complex systems, would be a huge step in establishing the potential of magnetic fusion energy to contribute to the world’s energy security. An integrated simulation capability would dramatically enhance the utilization of such a facility and lead to optimization of toroidal fusion plasmas in general. This science-based predictive capability, which was cited in the FESAC

  1. The potential of imposed magnetic fields for enhancing ignition probability and fusion energy yield in indirect-drive inertial confinement fusion

    Science.gov (United States)

    Perkins, L. J.; Ho, D. D.-M.; Logan, B. G.; Zimmerman, G. B.; Rhodes, M. A.; Strozzi, D. J.; Blackfield, D. T.; Hawkins, S. A.

    2017-06-01

    We examine the potential that imposed magnetic fields of tens of Tesla that increase to greater than 10 kT (100 MGauss) under implosion compression may relax the conditions required for ignition and propagating burn in indirect-drive inertial confinement fusion (ICF) targets. This may allow the attainment of ignition, or at least significant fusion energy yields, in presently performing ICF targets on the National Ignition Facility (NIF) that today are sub-marginal for thermonuclear burn through adverse hydrodynamic conditions at stagnation [Doeppner et al., Phys. Rev. Lett. 115, 055001 (2015)]. Results of detailed two-dimensional radiation-hydrodynamic-burn simulations applied to NIF capsule implosions with low-mode shape perturbations and residual kinetic energy loss indicate that such compressed fields may increase the probability for ignition through range reduction of fusion alpha particles, suppression of electron heat conduction, and potential stabilization of higher-mode Rayleigh-Taylor instabilities. Optimum initial applied fields are found to be around 50 T. Given that the full plasma structure at capsule stagnation may be governed by three-dimensional resistive magneto-hydrodynamics, the formation of closed magnetic field lines might further augment ignition prospects. Experiments are now required to further assess the potential of applied magnetic fields to ICF ignition and burn on NIF.

  2. Understanding plasma facing surfaces in magnetic fusion devices

    Science.gov (United States)

    Skinner, C. H.; Capece, A. M.; Koel, B. E.; Roszell, J. P.

    2013-09-01

    The plasma-material interface is recognized to be the most critical challenge in the realization of fusion energy. Liquid metals offer a self-healing, renewable interface that bypasses present issues with solid, neutron-damaged materials such as tungsten. Lithium in particular has dramatically improved plasma performance in many tokamaks through a reduction of hydrogen recycling. However the detailed chemical composition and properties of the top few nm that interact with the plasma are often obscure. Surface analysis has proven to be a key tool in semiconductor processing and a new laboratory has been established at PPPL to apply surface science techniques to plasma facing materials. We have shown that lithiated PFC surfaces in tokamaks will likely be oxidized during the intershot interval. Present work is focused on deuterium uptake of solid and liquid metals for plasma density control and sub-micron scale wetting of liquid metals on their substrates. The long-term goal is to provide a material database for designing liquid metal plasma facing components for tokamaks such as National Spherical Torus Experiment-Upgrade (NSTX-U) and Fusion Nuclear Science Facility-ST (FNSF-ST). Support was provided through DOE-PPPL Contract Number is DE-AC02-09CH11466.

  3. Development of a cryogenically cooled platform for the Magnetized Liner Inertial Fusion (MagLIF) Program

    Science.gov (United States)

    Awe, T. J.; Shelton, K. P.; Sefkow, A. B.; Lamppa, D. C.; Baker, J. L.; Rovang, D. C.; Robertson, G. K.

    2017-09-01

    A cryogenically cooled hardware platform has been developed and commissioned on the Z Facility at Sandia National Laboratories in support of the Magnetized Liner Inertial Fusion (MagLIF) Program. MagLIF is a magneto-inertial fusion concept that employs a magnetically imploded metallic tube (liner) to compress and inertially confine premagnetized and preheated fusion fuel. The fuel is preheated using a ˜2 kJ laser that must pass through a ˜1.5-3.5-μm-thick polyimide "window" at the target's laser entrance hole (LEH). As the terawatt-class laser interacts with the dense window, laser plasma instabilities (LPIs) can develop, which reduce the preheat energy delivered to the fuel, initiate fuel contamination, and degrade target performance. Cryogenically cooled targets increase the parameter space accessible to MagLIF target designs by allowing nearly 10 times thinner windows to be used for any accessible gas density. Thinner LEH windows reduce the deleterious effects of difficult to model LPIs. The Z Facility's cryogenic infrastructure has been significantly altered to enable compatibility with the premagnetization and fuel preheat stages of MagLIF. The MagLIF cryostat brings the liquid helium coolant directly to the target via an electrically resistive conduit. This design maximizes cooling power while allowing rapid diffusion of the axial magnetic field supplied by external Helmholtz-like coils. A variety of techniques have been developed to mitigate the accumulation of ice from vacuum chamber contaminants on the cooled LEH window, as even a few hundred nanometers of ice would impact laser energy coupling to the fuel region. The MagLIF cryostat has demonstrated compatibility with the premagnetization and preheat stages of MagLIF and the ability to cool targets to liquid deuterium temperatures in approximately 5 min.

  4. Computational challenges in magnetic-confinement fusion physics

    Science.gov (United States)

    Fasoli, A.; Brunner, S.; Cooper, W. A.; Graves, J. P.; Ricci, P.; Sauter, O.; Villard, L.

    2016-05-01

    Magnetic-fusion plasmas are complex self-organized systems with an extremely wide range of spatial and temporal scales, from the electron-orbit scales (~10-11 s, ~ 10-5 m) to the diffusion time of electrical current through the plasma (~102 s) and the distance along the magnetic field between two solid surfaces in the region that determines the plasma-wall interactions (~100 m). The description of the individual phenomena and of the nonlinear coupling between them involves a hierarchy of models, which, when applied to realistic configurations, require the most advanced numerical techniques and algorithms and the use of state-of-the-art high-performance computers. The common thread of such models resides in the fact that the plasma components are at the same time sources of electromagnetic fields, via the charge and current densities that they generate, and subject to the action of electromagnetic fields. This leads to a wide variety of plasma modes of oscillations that resonate with the particle or fluid motion and makes the plasma dynamics much richer than that of conventional, neutral fluids.

  5. Assessment of contemporary mathematical methods for magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Treve, Y. M.

    1978-03-01

    The mathematical techniques reviewed have been selected on the basis of their relevance to at least four outstanding theoretical problems of magnetic fusion research, namely: (a) ion heating; (b) particle-wave interactions; (c) stability of magnetic surfaces in real tokamaks; and (d) strong plasma turbulence. These problems have a common feature: they all involve chaotic motions in spite of the perfectly deterministic nature of the mathematical models used for their description. In the first section devoted to Hamiltonian systems we briefly review the essentials of the Hamilton-Jacobi theory and discuss the Kolmogorov-Arnold-Moser theorem and its implications. In section 2 we review the difficulties of the problem of turbulence and present the Ruelle-Takens picture. An example of a dynamical system with a strange attractor is constructed and the Hopf bifurcation theory is discussed. Finally we review the properties of the Lorenz model for the convective instability of an atmospheric layer which is known to have a strange attractor for sufficiently high Rayleigh numbers.

  6. Flyer-Plate-Based Current Diagnostic for Magnetized Liner Inertial Fusion Experiments

    Science.gov (United States)

    Reneker, Joseph; Gomez, Matthew; Hess, Mark; Jennings, Christopher

    2015-11-01

    Accurate measurements of the current delivered to Magnetized Liner Inertial Fusion (MagLIF) loads on the Z machine are important for understanding the dynamics of liner implosions. Difficulty acquiring a reliable load current measurement with the standard Z load B-dots has spurred the development of alternative load current diagnostics. Velocimetry of an electromagnetically-accelerated flyer plate can be used to infer the drive current on a flyer surface. A load current diagnostic design is proposed using a cylindrical flyer plate in series with the MagLIF target. Aspects of the flyer plate design were optimized using magnetohydrodynamic simulations. Design and preliminary results will be presented. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  7. Diagnosing laser-preheated magnetized plasmas relevant to magnetized liner inertial fusion

    Science.gov (United States)

    Harvey-Thompson, A. J.; Sefkow, A. B.; Nagayama, T. N.; Wei, M. S.; Campbell, E. M.; Fiksel, G.; Chang, P.-Y.; Davies, J. R.; Barnak, D. H.; Glebov, V. Y.; Fitzsimmons, P.; Fooks, J.; Blue, B. E.

    2015-12-01

    We present a platform on the OMEGA EP Laser Facility that creates and diagnoses the conditions present during the preheat stage of the MAGnetized Liner Inertial Fusion (MagLIF) concept. Experiments were conducted using 9 kJ of 3ω (355 nm) light to heat an underdense deuterium gas (electron density: 2.5 ×1020 cm-3=0.025 of critical density) magnetized with a 10 T axial field. Results show that the deuterium plasma reached a peak electron temperature of 670 ± 140 eV, diagnosed using streaked spectroscopy of an argon dopant. The results demonstrate that plasmas relevant to the preheat stage of MagLIF can be produced at multiple laser facilities, thereby enabling more rapid progress in understanding magnetized preheat. Results are compared with magneto-radiation-hydrodynamics simulations, and plans for future experiments are described.

  8. The effects of magnetic field topology on secondary neutron spectra in Magnetized Liner Inertial Fusion

    Science.gov (United States)

    Appelbe, B.; Pecover, J.; Chittenden, J.

    2017-03-01

    The Magnetized Liner Inertial Fusion (MagLIF) concept involves the compression of a magnetized fuel such that the stagnated fuel contains a magnetic field that can suppress heat flow losses and confine α particles. Magnetic confinement of α particles reduces the fuel ρR required for ignition. Recent work [1,2] has demonstrated that the magnitude of the magnetic field in deuterium fuel can be inferred from the yields and spectra of secondary DT neutrons. In this work we investigate the potential for using the shape of the secondary neutron spectra to diagnose the magnetic field topology in the stagnated fuel. Three different field topologies that could possibly occur in MagLIF experiments are studied: (1) a cylindrical fuel column containing axial and azimuthal magnetic field components, (2) a fuel column which is pinched at the ends to form a magnetic mirror and (3) a fuel column that has a helical tube shape with magnetic field lines following the helical path of the tube's axis. Each topology is motivated by observations from experimental or simulated MagLIF data. For each topology we use a multi-physics model to investigate the shapes of the secondary neutron spectra emitted from a steady-state stagnated fuel column. It is found that the azimuthal and helical topologies are more suitable than the mirror topology for reproducing an asymmetry in the axial spectra that was observed in experiments. Gorgon MHD simulations of the MagLIF implosion in 1D are also carried out. These show that sufficient azimuthal magnetic field can penetrate from the liner into the fuel to qualitatively reproduce the observed spectral asymmetry.

  9. Magnetic fusion energy annual report, July 1975--September 1976

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, M.A.; McGregor, C.K.; Gottlieb, L. (eds.)

    1976-12-02

    Supporting research activities continued to provide the technical basis for future mirror-confinement experiments. The industrial development of a high-current, high-field, high-current-density Nb/sub 3/Sn conductor was the main goal of the superconducting magnet program. Beam direct conversion was being developed as a means of raising the efficiency of neutral-beam production, and plasma direct conversion was shown to work as predicted. Conceptual designs were completed for various types of power reactors. The neutral-beam program progressed in three areas: experimental work, facility construction, and conceptual design. Experiments on the 14-MeV Rotating Target Neutron Source (RTNS-II) included participation by experimenters from many different institutions. Methods for processing tritium-contaminated wastes were pursued, as were studies of tritiated methane in stainless-steel vessels, the control of tritium in mirror fusion reactors, and the development of titanium tritide targets for the RTNS. The report period witnessed a rapid maturation in ability to describe theoretically the behavior of ion-cyclotron noise in the 2XIIB and the influence of that noise on the confined plasma. The high beta values achieved in 2XIIB prompted much theoretical analysis of the properties of high-beta equilibria and stability, including those of a field-reversed state. Excellent progress was made on the development of computer codes applicable to magnetic-mirror problems, with emphasis on three-dimensional, finite-beta, guiding-center equilibria, field-reversal, and Fokker-Planck codes.

  10. Modification of stagnation conditions in Magnetized Liner Inertial Fusion via thick dielectric coating

    Science.gov (United States)

    Gomez, M. R.; Harding, E. C.; Peterson, K. J.; Awe, T. J.; Ampleford, D. J.; Hansen, S. B.; Jennings, C. A.; Weis, M. R.; Chandler, G. A.; Hahn, K. D.; Knapp, P. F.; Martin, M. R.; McBride, R. D.; Rochau, G. A.; Sefkow, A. B.; Sinars, D. B.; Yu, E. P.

    2016-10-01

    Magnetized Liner Inertial Fusion (MagLIF) experiments on the Z facility at Sandia National Laboratories use approximately 20 MA of current to implode a metal cylinder, which contains axially-magnetized, laser-heated deuterium fuel. MagLIF experiments have demonstrated primary DD neutron yields up to 3e12 with burn averaged ion temperatures of 2.5 keV. X-ray emission at stagnation, recorded with a spherically-bent crystal imager, shows a weakly-helical structure with axial variations in intensity. Previously, the application of a thick dielectric coating to the exterior of an imploding cylinder has shown improved stability of the cylinder throughout the implosion. We recently demonstrated that adding a dielectric coating to a MagLIF target produces a cylindrical, rather than helical, stagnation column with reduced axial variations in intensity. There are also indications of decreased late-time mix in the x-ray spectra. This is consistent with a more uniform, stable stagnation column. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  11. Fusion

    CERN Document Server

    Mahaffey, James A

    2012-01-01

    As energy problems of the world grow, work toward fusion power continues at a greater pace than ever before. The topic of fusion is one that is often met with the most recognition and interest in the nuclear power arena. Written in clear and jargon-free prose, Fusion explores the big bang of creation to the blackout death of worn-out stars. A brief history of fusion research, beginning with the first tentative theories in the early 20th century, is also discussed, as well as the race for fusion power. This brand-new, full-color resource examines the various programs currently being funded or p

  12. Issues in the commercialization of magnetic fusion power

    Energy Technology Data Exchange (ETDEWEB)

    Rockwood, A.D.; Willke, T.L.

    1979-12-01

    This study identifies and outlines the issues that must be considered if fusion is to be put into commercial practice. The issues are put into perspective around a consistent framework and a program of study and research is recommended to anticipate and handle the issues for a successful fusion commercialization program. (MOW)

  13. Magnetized target fusion: An ultra high energy approach in an unexplored parameter space

    Energy Technology Data Exchange (ETDEWEB)

    Lindemuth, I.R.

    1994-12-31

    Magnetized target fusion is a concept that may lead to practical fusion applications in a variety of settings. However, the crucial first step is to demonstrate that it works as advertised. Among the possibilities for doing this is an ultrahigh energy approach to magnetized target fusion, one powered by explosive pulsed power generators that have become available for application to thermonuclear fusion research. In a collaborative effort between Los Alamos and the All-Russian Scientific Institute for Experimental Physics (VNIIEF) a very powerful helical generator with explosive power switching has been used to produce an energetic magnetized plasma. Several diagnostics have been fielded to ascertain the properties of this plasma. We are intensively studying the results of the experiments and calculationally analyzing the performance of this experiment.

  14. AI/Simulation Fusion Project at Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, S.A.

    1984-04-25

    This presentation first discusses the motivation for the AI Simulation Fusion project. After discussing very briefly what expert systems are in general, what object oriented languages are in general, and some observed features of typical combat simulations, it discusses why putting together artificial intelligence and combat simulation makes sense. We then talk about the first demonstration goal for this fusion project.

  15. Fusion energy in an inertial electrostatic confinement device using a magnetically shielded grid

    Energy Technology Data Exchange (ETDEWEB)

    Hedditch, John, E-mail: john.hedditch@sydney.edu.au; Bowden-Reid, Richard, E-mail: rbow3948@physics.usyd.edu.au; Khachan, Joe, E-mail: joe.khachan@sydney.edu.au [School of Physics, The University of Sydney, Sydney, New South Whales 2006 (Australia)

    2015-10-15

    Theory for a gridded inertial electrostatic confinement (IEC) fusion system is presented, which shows a net energy gain is possible if the grid is magnetically shielded from ion impact. A simplified grid geometry is studied, consisting of two negatively biased coaxial current-carrying rings, oriented such that their opposing magnetic fields produce a spindle cusp. Our analysis indicates that better than break-even performance is possible even in a deuterium-deuterium system at bench-top scales. The proposed device has the unusual property that it can avoid both the cusp losses of traditional magnetic fusion systems and the grid losses of traditional IEC configurations.

  16. Fusion in a magnetically-shielded-grid inertial electrostatic confinement device

    CERN Document Server

    Hedditch, John; Khachan, Joe

    2015-01-01

    Theory for a gridded inertial electrostatic confinement (IEC) fusion system is presented that shows a net energy gain is possible if the grid is magnetically shielded from ion impact. A simplified grid geometry is studied, consisting of two negatively-biased coaxial current-carrying rings, oriented such that their opposing magnetic fields produce a spindle cusp. Our analysis indicates that better than break-even performance is possible even in a deuterium-deuterium system at bench-top scales. The proposed device has the unusual property that it can avoid both the cusp losses of traditional magnetic fusion systems and the grid losses of traditional IEC configurations.

  17. Controlled Nuclear Fusion by Magnetic Confinement and ITER

    CERN Document Server

    CERN. Geneva. Audiovisual Unit; Alvarez-Gaumé, Luís

    2005-01-01

    For may years harnessing fusion energy was considered the final solution to the world's energy crisis. ITER is the last step in the elusive quest. This presentation will provide in its various acientific, technological and political aspects.

  18. The role of the National Ignition Facility in the development of inertial fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    Logan, B.G.

    1996-06-01

    The authors have completed a conceptual design for a 1.8-MJ, 500-TW, 0.35-{mu}m solid-state laser system for the National Ignition Facility (NIF), which will demonstrate inertial fusion ignition and gain for national security, energy, and science applications. The technical goal of the U.S. Inertial Confinement Fusion (ICF) Program as stated in the current ICF Five-Year Program Plan is {open_quotes}to produce pure fusion ignition and burn in the laboratory, with fusion yields of 200 to 1000 MJ, in support of three missions: (1) to play an essential role in accessing physics regimes of interest in nuclear weapon design...; (2) to provide an above-ground simulation capability for nuclear weapon effects...; and (3) to develop inertial fusion energy for civilian power production.{close_quotes} This article addresses the third goal-- the development of inertial fusion energy (IFE). This article reports a variety of potential contributions the NIF could make to the development of IFE, drawn from a nationally attended workshop held at the University of California at Berkeley in Feb, 1994. In addition to demonstrating fusion ignition as a fundamental basis for IFE, the findings of the workshop, are that the NIF could also provide important data for target physics and fabrication technology, for IFE target chamber phenomena such as materials responses to target emissions, and for fusion power technology-relevant tests.

  19. Exploring magnetized liner inertial fusion with a semi-analytic model

    Science.gov (United States)

    McBride, R. D.; Slutz, S. A.; Sinars, D. B.; Vesey, R. A.; Gomez, M. R.; Sefkow, A. B.; Hansen, S. B.; Cochrane, K. R.; Schmit, P. F.; Knapp, P. F.; Geissel, M.; Harvey-Thompson, A. J.; Jennings, C. A.; Martin, M. R.; Awe, T. J.; Rovang, D. C.; Lamppa, D. C.; Peterson, K. J.; Rochau, G. A.; Porter, J. L.; Stygar, W. A.; Cuneo, M. E.

    2015-11-01

    In this presentation, we explore magnetized liner inertial fusion (MagLIF) using a semi-analytic model. Specifically, we present simulation results from this model that: (a) illustrate the parameter space, energetics, and overall system efficiencies of MagLIF; (b) demonstrate the dependence of radiative loss rates on the radial fraction of the fuel that is preheated; (c) explore some of the recent experimental results of the MagLIF program at Sandia National Laboratories; (d) highlight the experimental challenges presently facing the MagLIF program (as MagLIF is first being tested using the infrastructure presently available at the Z pulsed-power facility); and (e) demonstrate how these challenges could change as various system upgrades are made to the Z facility over the next three to five years and beyond. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  20. Research Needs for Magnetic Fusion Energy Sciences. Report of the Research Needs Workshop (ReNeW) Bethesda, Maryland, June 8-12, 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-06-08

    Nuclear fusion - the process that powers the sun - offers an environmentally benign, intrinsically safe energy source with an abundant supply of low-cost fuel. It is the focus of an international research program, including the ITE R fusion collaboration, which involves seven parties representing half the world's population. The realization of fusion power would change the economics and ecology of energy production as profoundly as petroleum exploitation did two centuries ago. The 21st century finds fusion research in a transformed landscape. The worldwide fusion community broadly agrees that the science has advanced to the point where an aggressive action plan, aimed at the remaining barriers to practical fusion energy, is warranted. At the same time, and largely because of its scientific advance, the program faces new challenges; above all it is challenged to demonstrate the timeliness of its promised benefits. In response to this changed landscape, the Office of Fusion Energy Sciences (OFES ) in the US Department of Energy commissioned a number of community-based studies of the key scientific and technical foci of magnetic fusion research. The Research Needs Workshop (ReNeW) for Magnetic Fusion Energy Sciences is a capstone to these studies. In the context of magnetic fusion energy, ReNeW surveyed the issues identified in previous studies, and used them as a starting point to define and characterize the research activities that the advance of fusion as a practical energy source will require. Thus, ReNeW's task was to identify (1) the scientific and technological research frontiers of the fusion program, and, especially, (2) a set of activities that will most effectively advance those frontiers. (Note that ReNeW was not charged with developing a strategic plan or timeline for the implementation of fusion power.) This Report presents a portfolio of research activities for US research in magnetic fusion for the next two decades. It is intended to provide

  1. Prospects of steady state magnetic diagnostic of fusion reactors based on metallic Hall sensors

    Science.gov (United States)

    Ďuran, I.; Sentkerestiová, J.; Kovařík, K.; Viererbl, L.

    2012-06-01

    Employment of sensors based on Hall effect (Hall sensors) is one of the candidate approaches to detection of almost steady state magnetic fields in future fusion reactors based on magnetic confinement (tokamaks, stellarators etc.), and also in possible fusion-fission hybrid systems having these fusion reactors as a neutron source and driver. This contribution reviews the initial considerations concerning application of metallic Hall sensors in fusion reactor harsh environment that include high neutron loads (>1018 cm-2) and elevated temperatures (>200°C). In particular, the candidate sensing materials, candidate technologies for sensors production, initial analysis of activation and transmutation of sensors under reactor relevant neutron loads and the tests of the the first samples of copper Hall sensors are presented.

  2. Development of 2D/3D equilibrium codes for magnetically confined fusion experiments

    OpenAIRE

    2013-01-01

    The present work is the result of a three-year Ph.D. research project carried out at Consorzio RFX on magnetically confined plasmas. Research on controlled thermonuclear fusion is currently being pursued by many countries throughout the world, thanks to its promise of a relatively clean and abundant energy source. The next steps for the international community are the construction and operation of a large device, ITER, considered as the last fusion physics experiment with respect to the tokam...

  3. Fusion an introduction to the physics and technology of magnetic confinement fusion

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    This second edition of a popular textbook is thoroughly revised with around 25% new and updated content.It provides an introduction to both plasma physics and fusion technology at a level that can be understood by advanced undergraduates and graduate students in the physical sciences and related engineering disciplines.As such, the contents cover various plasma confinement concepts, the support technologies needed to confine the plasma, and the designs of ITER as well as future fusion reactors.With end of chapter problems for use in courses.

  4. Demountable Toroidal Field Magnets for Use in a Compact Modular Fusion Reactor

    Science.gov (United States)

    Mangiarotti, F. J.; Goh, J.; Takayasu, M.; Bromberg, L.; Minervini, J. V.; Whyte, D.

    2014-05-01

    A concept of demountable toroidal field magnets for a compact fusion reactor is discussed. The magnets generate a magnetic field of 9.2 T on axis, in a 3.3 m major radius tokamak. Subcooled YBCO conductors have a critical current density adequate to provide this large magnetic field, while operating at 20 K reduces thermodynamic cooling cost of the resistive electrical joints. Demountable magnets allow for vertical replacement and maintenance of internal components, potentially reducing cost and time of maintenance when compared to traditional sector maintenance. Preliminary measurements of contact resistance of a demountable YBCO electrical joint between are presented.

  5. Inertial confinement fusion with direct electric generation by magnetic flux comparession

    Energy Technology Data Exchange (ETDEWEB)

    Lasche, G.P.

    1983-01-01

    A high-power-density laser-fusion-reactor concept in investigated in which directed kinetic enery imparted to a large mass of liquid lithium--in which the fusion target is centrally located--is maximized. In turn, this kinetic energy is converted directly to electricity with, potentially, very high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the concept maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall can be many orders of magnitude less than is typical of D-T fusion reactor concepts.

  6. Study of laser preheat in magnetic liner inertial fusion using the AMR code FLASH

    Science.gov (United States)

    Adams, Marissa; Jennings, Christopher; Slutz, Stephen; Peterson, Kyle; Gourdain, Pierre-Alexandre; University of Rochester; Sandia National Laboratories Collaboration

    2016-10-01

    Magnetic Liner Inertial Fusion (MagLIF) on the Z Pulsed Power Accelerator involves three processes: magnetization, preheat, and compression. An issue with this scheme is the development of instabilities during laser preheat, where the Z-Beamlet laser system may not deposit energy into deuterium fuel uniformly. This study explores potential mixing between liner and fuel, and inner imprinting of seeds on a beryllium liner that may generate late instability growth and shear, using the Eulerian AMR code FLASH. We further investigate potential instability implications of an additional layer of deuterium-tritium ice, as has been proposed and assess the sensitivity of MagLIF implosions to axial variations in fuel preheat; meanwhile testing the expediency of FLASH for these scenarios. FLASH was developed in part by the DOE NNSA ASC and DOE Office of Science ASCR-supported Flash Center at the University of Chicago. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin comapny, for the U.S. Department of Energy's National Nuclear Security Administration under contract No. DE-AC04-94AL85000.

  7. FED-R: a fusion engineering device utilizing resistive magnets

    Energy Technology Data Exchange (ETDEWEB)

    Jassby, D.L.; Kalsi, S.S. (eds.)

    1983-04-01

    The principal purpose of the FED-R tokamak facility is to provide a substantial quasi-steady flux of fusion neutrons irradiating a large test area in order to carry out thermal, neutronic, and radiation effects testing of experimental blanket assemblies having a variety of configurations, compositions, and purposes. The design of the FED-R device also suggests potential for an upgrade that could be employed as a full-scale demonstration reactor for some specific fusion-neutron application when required.

  8. Fusion

    Science.gov (United States)

    Herman, Robin

    1990-10-01

    The book abounds with fascinating anecdotes about fusion's rocky path: the spurious claim by Argentine dictator Juan Peron in 1951 that his country had built a working fusion reactor, the rush by the United States to drop secrecy and publicize its fusion work as a propaganda offensive after the Russian success with Sputnik; the fortune Penthouse magazine publisher Bob Guccione sank into an unconventional fusion device, the skepticism that met an assertion by two University of Utah chemists in 1989 that they had created "cold fusion" in a bottle. Aimed at a general audience, the book describes the scientific basis of controlled fusion--the fusing of atomic nuclei, under conditions hotter than the sun, to release energy. Using personal recollections of scientists involved, it traces the history of this little-known international race that began during the Cold War in secret laboratories in the United States, Great Britain and the Soviet Union, and evolved into an astonishingly open collaboration between East and West.

  9. Contribution to the study of superconducting magnetic systems in the frame of fusion projects

    Energy Technology Data Exchange (ETDEWEB)

    Duchateau, J.L.; Artiguelongue, H.; Bej, Z.; Ciazynski, D.; Cloez, H.; Decool, P.; Hertout, P.; Libeyre, P.; Martinez, A.; Nicollet, S.; Rubino, M.; Schild, T.; Verger, J.M. [Association Euratom-CEA, CEA/Cadarache, Dept. de Recherches sur la Fusion Controlee DRFC, 13 - Saint-Paul-lez-Durance (France)

    2000-02-01

    This report is a presentation of all the 55 publications made by the Magnet Group of the 'Departement de Recherche sur la Fusion Controlee' during the 94-99 period. These publications have been made mainly in the frame of EURATOM contracts and task for ITER. This collection deals with most of the dimensioning aspects of large superconducting magnets and hence the field interest is wider than the restricted field of magnets for fusion by magnetic confinement. Whenever it is possible, simple expressions and criteria are given for dimensioning superconducting strands, assembling them to build cables and cooling them by an adapted forced flow cooling. This is hence a major for the understanding of the behaviour of large modern superconducting magnets and provides many tools for design and construction. (author)

  10. The economic effect of using magnetic resonance imaging and magnetic resonance ultrasound fusion biopsy for prostate cancer diagnosis.

    Science.gov (United States)

    Hutchinson, Ryan C; Costa, Daniel N; Lotan, Yair

    2016-07-01

    Prostate magnetic resonance imaging (MRI) is a maturing imaging modality that has been used to improve detection and staging of prostate cancer. The goal of this review is to evaluate the economic effect of the use of MRI and MRI fusion in the diagnosis of prostate cancer. A literature review was used to identify articles regarding efficacy and cost of MRI and MRI-guided biopsies. There are currently a limited number of studies evaluating cost of incorporating MRI into clinical practice. These studies are primarily models projecting cost estimates based on meta-analyses of the literature. There is considerable variance in the effectiveness of MRI-guided biopsies, both cognitive and fusion, based on user experience, type of MRI (3T vs. 1.5T), use of endorectal coil and type of scoring system for abnormalities such that there is still potential for improvement in accuracy. There is also variability in assumed costs of incorporating MRI into clinical practice. The addition of MRI to the diagnostic algorithm for prostate cancer has caused a shift in how we understand the disease and in what tumors are found on initial and repeat biopsies. Further risk stratification may allow more men to pursue noncurative therapy, which in and of itself is cost-effective in properly selected men. As prostate cancer care comes under increasing scrutiny on a national level, there is pressure on providers to be more accurate in their diagnoses. This in turn can lead to additional testing including Multiparametric MRI, which adds upfront cost. Whether the additional cost of prostate MRI is warranted in detection of prostate cancer is an area of intense research. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. The National Network of Fusion Centers: Perception and Reality

    Science.gov (United States)

    2014-12-01

    11. U.S. Department of Homeland Security, “Fusion Center Success Stories,” accessed March 15, 2014, http:// ipv6 .dhs.gov/files/programs...collaboration with federal partners, the NFCA should mobilize the cadre of the Governors Homeland Security Advisors Council

  12. Calculation of fusion gain in fast ignition with magnetic target by relativistic electrons and protons

    Directory of Open Access Journals (Sweden)

    A Parvazian

    2010-12-01

    Full Text Available Fast ignition is a new method for inertial confinement fusion (ICF in which the compression and ignition steps are separated. In the first stage, fuel is compressed by laser or ion beams. In the second phase, relativistic electrons are generated by pettawat laser in the fuel. Also, in the second phase 5-35 MeV protons can be generated in the fuel. Electrons or protons can penetrate in to the ultra-dense fuel and deposit their energy in the fuel . More recently, cylindrical rather than spherical fuel chambers with magnetic control in the plasma domain have been also considered. This is called magnetized target fusion (MTF. Magnetic field has effects on relativistic electrons energy deposition rate in fuel. In this work, fast ignition method in cylindrical fuel chambers is investigated and transportation of the relativistic electrons and protons is calculated using MCNPX and FLUKA codes with 0. 25 and 0. 5 tesla magnetic field in single and dual hot spot. Furthermore, the transfer rate of relativistic electrons and high energy protons to the fuel and fusion gain are calculated. The results show that the presence of external magnetic field guarantees higher fusion gain, and relativistic electrons are much more appropriate objects for ignition. MTF in dual hot spot can be considered as an appropriate substitution for the current ICF techniques.

  13. Understanding fuel magnetization and mix using secondary nuclear reactions in magneto-inertial fusion.

    Science.gov (United States)

    Schmit, P F; Knapp, P F; Hansen, S B; Gomez, M R; Hahn, K D; Sinars, D B; Peterson, K J; Slutz, S A; Sefkow, A B; Awe, T J; Harding, E; Jennings, C A; Chandler, G A; Cooper, G W; Cuneo, M E; Geissel, M; Harvey-Thompson, A J; Herrmann, M C; Hess, M H; Johns, O; Lamppa, D C; Martin, M R; McBride, R D; Porter, J L; Robertson, G K; Rochau, G A; Rovang, D C; Ruiz, C L; Savage, M E; Smith, I C; Stygar, W A; Vesey, R A

    2014-10-10

    Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs.

  14. Cable-in-conduit superconductors for fusion magnets: electro-magnetic modelling for understanding and optimizing their transport properties

    NARCIS (Netherlands)

    Rolando, Gabriella

    2013-01-01

    Cable-In-Conduit conductors feature large current-carrying capacity and stability against local and transient heat deposition. As such they are suitable for application in superconducting magnets for nuclear fusion, as the ones of the International Thermonuclear Experimental Reactor (ITER). Due to

  15. Cable-in-conduit superconductors for fusion magnets: electro-magnetic modelling for understanding and optimizing their transport properties

    NARCIS (Netherlands)

    Rolando, G.

    2013-01-01

    Cable-In-Conduit conductors feature large current-carrying capacity and stability against local and transient heat deposition. As such they are suitable for application in superconducting magnets for nuclear fusion, as the ones of the International Thermonuclear Experimental Reactor (ITER). Due to t

  16. Magnetic Probe to Study Plasma Jets for Magneto-Inertial Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Martens, Daniel [Los Alamos National Laboratory; Hsu, Scott C. [Los Alamos National Laboratory

    2012-08-16

    A probe has been constructed to measure the magnetic field of a plasma jet generated by a pulsed plasma rail-gun. The probe consists of two sets of three orthogonally-oriented commercial chip inductors to measure the three-dimensional magnetic field vector at two separate positions in order to give information about the magnetic field evolution within the jet. The strength and evolution of the magnetic field is one of many factors important in evaluating the use of supersonic plasma jets for forming imploding spherical plasma liners as a standoff driver for magneto-inertial fusion.

  17. Computed tomography and magnetic resonance fusion imaging in cholesteatoma preoperative assessment.

    Science.gov (United States)

    Campos, Agustín; Mata, Federico; Reboll, Rosa; Peris, María Luisa; Basterra, Jorge

    2017-03-01

    The purpose of this study is to describe a method for developing fusion imaging for the preoperative evaluation of cholesteatoma. In 33 patients diagnosed with cholesteatoma, a high-resolution temporal bone computed tomography (CT) scan without intravenous contrast and propeller diffusion-weighted magnetic resonance imaging (MRI) were performed. Both studies were then sent to the BrainLAB work station, where the images were fused to obtain a morphological and color map. Intraoperative findings coincided with fusion CT-MRI imaging in all but two patients. In addition, one false positive and one false negative case were observed. CT and diffusion-weighted MRI are complementary techniques that should be employed to assess a cholesteatoma prior to surgery in many cases. Hence, to combine the advantages of each technique, we developed a fusion image technique similar to those that are routinely employed for radiotherapy planning and positron emission tomography-CT imaging. Fusion images can prove useful in selected cases.

  18. Magnetic flux and heat losses by diffusive, advective, and Nernst effects in magnetized liner inertial fusion-like plasma

    Energy Technology Data Exchange (ETDEWEB)

    Velikovich, A. L.; Giuliani, J. L. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Zalesak, S. T. [Berkeley Research Associates, Beltsville, Maryland 20705 (United States)

    2015-04-15

    The magnetized liner inertial fusion (MagLIF) approach to inertial confinement fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010); Cuneo et al., IEEE Trans. Plasma Sci. 40, 3222 (2012)] involves subsonic/isobaric compression and heating of a deuterium-tritium plasma with frozen-in magnetic flux by a heavy cylindrical liner. The losses of heat and magnetic flux from the plasma to the liner are thereby determined by plasma advection and gradient-driven transport processes, such as thermal conductivity, magnetic field diffusion, and thermomagnetic effects. Theoretical analysis based on obtaining exact self-similar solutions of the classical collisional Braginskii's plasma transport equations in one dimension demonstrates that the heat loss from the hot compressed magnetized plasma to the cold liner is dominated by transverse heat conduction and advection, and the corresponding loss of magnetic flux is dominated by advection and the Nernst effect. For a large electron Hall parameter (ω{sub e}τ{sub e}≫1), the effective diffusion coefficients determining the losses of heat and magnetic flux to the liner wall are both shown to decrease with ω{sub e}τ{sub e} as does the Bohm diffusion coefficient cT/(16eB), which is commonly associated with low collisionality and two-dimensional transport. We demonstrate how this family of exact solutions can be used for verification of codes that model the MagLIF plasma dynamics.

  19. Magnetic flux and heat losses by diffusive, advective, and Nernst effects in magnetized liner inertial fusion-like plasma

    Science.gov (United States)

    Velikovich, A. L.; Giuliani, J. L.; Zalesak, S. T.

    2015-04-01

    The magnetized liner inertial fusion (MagLIF) approach to inertial confinement fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010); Cuneo et al., IEEE Trans. Plasma Sci. 40, 3222 (2012)] involves subsonic/isobaric compression and heating of a deuterium-tritium plasma with frozen-in magnetic flux by a heavy cylindrical liner. The losses of heat and magnetic flux from the plasma to the liner are thereby determined by plasma advection and gradient-driven transport processes, such as thermal conductivity, magnetic field diffusion, and thermomagnetic effects. Theoretical analysis based on obtaining exact self-similar solutions of the classical collisional Braginskii's plasma transport equations in one dimension demonstrates that the heat loss from the hot compressed magnetized plasma to the cold liner is dominated by transverse heat conduction and advection, and the corresponding loss of magnetic flux is dominated by advection and the Nernst effect. For a large electron Hall parameter ( ωeτe≫1 ), the effective diffusion coefficients determining the losses of heat and magnetic flux to the liner wall are both shown to decrease with ωeτe as does the Bohm diffusion coefficient c T /(16 e B ) , which is commonly associated with low collisionality and two-dimensional transport. We demonstrate how this family of exact solutions can be used for verification of codes that model the MagLIF plasma dynamics.

  20. LDRD final report on confinement of cluster fusion plasmas with magnetic fields.

    Energy Technology Data Exchange (ETDEWEB)

    Argo, Jeffrey W.; Kellogg, Jeffrey W.; Headley, Daniel Ignacio; Stoltzfus, Brian Scott; Waugh, Caleb J.; Lewis, Sean M.; Porter, John Larry, Jr.; Wisher, Matthew; Struve, Kenneth William; Savage, Mark Edward; Quevedo, Hernan J.; Bengtson, Roger

    2011-11-01

    Two versions of a current driver for single-turn, single-use 1-cm diameter magnetic field coils have been built and tested at the Sandia National Laboratories for use with cluster fusion experiments at the University of Texas in Austin. These coils are used to provide axial magnetic fields to slow radial loss of electrons from laser-produced deuterium plasmas. Typical peak field strength achievable for the two-capacitor system is 50 T, and 200 T for the ten-capacitor system. Current rise time for both systems is about 1.7 {mu}s, with peak current of 500 kA and 2 MA, respectively. Because the coil must be brought to the laser, the driver needs to be portable and drive currents in vacuum. The drivers are complete but laser-plasma experiments are still in progress. Therefore, in this report, we focus on system design, initial tests, and performance characteristics of the two-capacitor and ten-capacitors systems. The questions of whether a 200 T magnetic field can retard the breakup of a cluster-fusion plasma, and whether this field can enhance neutron production have not yet been answered. However, tools have been developed that will enable producing the magnetic fields needed to answer these questions. These are a two-capacitor, 400-kA system that was delivered to the University of Texas in 2010, and a 2-MA ten-capacitor system delivered this year. The first system allowed initial testing, and the second system will be able to produce the 200 T magnetic fields needed for cluster fusion experiments with a petawatt laser. The prototype 400-kA magnetic field driver system was designed and built to test the design concept for the system, and to verify that a portable driver system could be built that delivers current to a magnetic field coil in vacuum. This system was built copying a design from a fixed-facility, high-field machine at LANL, but made to be portable and to use a Z-machine-like vacuum insulator and vacuum transmission line. This system was sent to the

  1. Low-energy nuclear fusion data and their relation to magnetic and laser fusion

    Energy Technology Data Exchange (ETDEWEB)

    Jarmie, N.

    1980-04-01

    The accuracy of the basic fusion data for the T(d,n)/sup 4/He, /sup 3/He(d,p)/sup 4/He, T(t,2n)/sup 4/He, D(d,n)/sup 3/He, and D(d,p)T reactions was investigated in the 10- to 100-keV bombarding energy region, and the effects of inaccuracies on the design of fusion reactors were assessed. The data base for these reactions (particularly, the most critical T(d,n)/sup 4/He reaction) rests on 25-year-old experiments the accuracy (often assumed to be +- 5%) of which has rarely been questioned: yet, in all except the d + d reactions, there are significant differences among data sets. The errors in the basic data sets may be considerably larger than previously expected, and the effect on design calculations should be significant. Much of the trouble apparently lies in the accuracy of the energy measurements, which are difficult at low energies. Systematic errors of up to 50% are possible in the reactivity values of the present T(d,n)/sup 4/He data base. The errors in the reactivity will propagate proportionately into the errors in fusion probabilities in reactor calculations. /sup 3/He(d,p)/sup 4/He reaction cross sections could be in error by as much as 50% in the low-energy region. The D(d,n)/sup 3/He and D(d,p)T cross sections appear to be well known and consistent. The T(t,2n)/sup 4/He cross section is poorly known and may be subject to large systematic errors. Improved absolute measurements for all the reactions in the low bombarding energy region (10 to 100 keV) are needed, but until they are done, the data sets should be left as they are (except for T(t,2n)/sup 4/He data, which could be lowered by about 50%). The apparent uncertainties of these data sets should be kept in mind. 14 figures.

  2. Integrated simulation of magnetic-field-assist fast ignition laser fusion

    Science.gov (United States)

    Johzaki, T.; Nagatomo, H.; Sunahara, A.; Sentoku, Y.; Sakagami, H.; Hata, M.; Taguchi, T.; Mima, K.; Kai, Y.; Ajimi, D.; Isoda, T.; Endo, T.; Yogo, A.; Arikawa, Y.; Fujioka, S.; Shiraga, H.; Azechi, H.

    2017-01-01

    To enhance the core heating efficiency in fast ignition laser fusion, the concept of relativistic electron beam guiding by external magnetic fields was evaluated by integrated simulations for FIREX class targets. For the cone-attached shell target case, the core heating performance deteriorates by applying magnetic fields since the core is considerably deformed and most of the fast electrons are reflected due to the magnetic mirror formed through the implosion. On the other hand, in the case of a cone-attached solid ball target, the implosion is more stable under the kilo-tesla-class magnetic field. In addition, feasible magnetic field configuration is formed through the implosion. As a result, the core heating efficiency doubles by magnetic guiding. The dependence of core heating properties on the heating pulse shot timing was also investigated for the solid ball target.

  3. Integrated simulation of magnetic-field-assist fast ignition laser fusion

    CERN Document Server

    Johzaki, T; Sunahara, A; Sakagami, Y Sentoku H; Hata, M; Taguchi, T; Mima, K; Kai, Y; Ajimi, D; Endo, T; Yogo, A; Arikawa, Y; Fujioka, S; Shiraga, H; Azechi, H

    2016-01-01

    To enhance the core heating efficiency in fast ignition laser fusion, the concept of relativistic electron beam guiding by external magnetic fields was evaluated by integrated simulations for FIREX class targets. For the cone-attached shell target case, the core heating performance is deteriorated by applying magnetic fields since the core is considerably deformed and the most of the fast electrons are reflected due to the magnetic mirror formed through the implosion. On the other hand, in the case of cone-attached solid ball target, the implosion is more stable under the kilo-tesla-class magnetic field. In addition, feasible magnetic field configuration is formed through the implosion. As the results, the core heating efficiency becomes double by magnetic guiding. The dependence of core heating properties on the heating pulse shot timing was also investigated for the solid ball target.

  4. Magnetic monitoring in Saguaro National Park

    Science.gov (United States)

    Love, Jeffrey J.; Finn, Carol A.; Gamez Valdez, Yesenia C.; Swann, Don

    2017-06-02

    On a sandy, arid plain, near the Rincon Moun­tain Visitor Center of Saguaro National Park, tucked in among brittlebush, creosote, and other hardy desert plants, is an unusual type of observatory—a small unmanned station that is used for monitor­ing the Earth’s variable magnetic field. Named for the nearby city of Tucson, Arizona, the observatory is 1 of 14 that the Geomagnetism Program of the U.S. Geological Survey operates at various locations across the United States and Ter­ritories.Data from USGS magnetic observatories, including the Tucson observatory, as well as observatories operated by institutions in other countries, record a variety of signals related to a wide diversity of physical phenomena in the Earth’s interior and its surrounding outer-space environment. The data are used for geomagnetic mapping and surveying, for fundamental scientific research, and for assessment of magnetic storms, which can be hazardous for the activities and infra­structure of our modern, technologically based society. The U.S. Geological Survey observatory service is an integral part of a U.S. national project for monitoring and assessing space weather hazards.

  5. Assessment of liquid hydrogen cooled MgB2 conductors for magnetically confined fusion

    Science.gov (United States)

    Glowacki, B. A.; Nuttall, W. J.

    2008-02-01

    Importantly environmental factors are not the only policy-driver for the hydrogen economy. Over the timescale of the development of fusion energy systems, energy security issues are likely to motivate a shift towards both hydrogen production and fusion as an energy source. These technologies combine local control of the system with the collaborative research interests of the major energy users in the global economy. A concept Fusion Island Reactor that might be used to generate H2 (rather than electricity) is presented. Exploitation of produced hydrogen as a coolant and as a fuel is proposed in conjunction with MgB2 conductors for the tokomak magnets windings, and electrotechnical devices for Fusion Island's infrastructure. The benefits of using MgB2 over the Nb-based conductors during construction, operation and decommissioning of the Fusion Island Reactor are presented. The comparison of Nb3Sn strands for ITER fusion magnet with newly developed high field composite MgB2 PIT conductors has shown that at 14 Tesla MgB2 possesses better properties than any of the Nb3Sn conductors produced. In this paper the potential of MgB2 conductors is examined for tokamaks of both the conventional ITER type and a Spherical Tokamak geometry. In each case MgB2 is considered as a conductor for a range of field coil applications and the potential for operation at both liquid helium and liquid hydrogen temperatures is considered. Further research plans concerning the application of MgB2 conductors for Fusion Island are also considered.

  6. Mechanical behavior of the mirror fusion test Facility superconducting magnet coils

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, J.A.

    1980-01-01

    The mechanical response to winding and electromagnetic loads of the Mirror Fusion Test Facility (MFTF) superconducting coil pack is presented. The 375-ton (3300 N) MFTF Yin-Yang magnet, presently the world's largest superconducting magnet, is scheduled for acceptance cold-testing in May of 1981. The assembly is made up of two identical coils which together contain over 15 miles (24 km) of superconductor wound in 58 consecutive layers of 24 turns each. Topics associated with mechanical behavior include physical properties of the coil pack and its components, winding pre-load effects, finite element analysis, magnetic load redistribution, and the design impact of predicted conductor motion.

  7. A Study on Establishing National Technology Strategy of Fusion Energy Development: Combining PEST-SWOT Methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Han Soo; Choi, Won Jae; Tho, Hyun Soo; Kang, Dong Yup; Kim, In Chung [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Nuclear fusion, the joining of light nuclei of hydrogen into heavier nuclei of helium, has potential environmental, safety and proliferation characteristics as an energy source. It can also, provide an adequate amount of fuel to power civilization for a long time compared to human history. It is, however, more challenging to convert to an energy source than nuclear fission. To overcome this, Korea enacted a law to promote the development of fusion as an energy source in 2007. In accordance with this law, the government will establish a promotion plan to develop fusion energy, including policy goals, a framework, strategies, infrastructure, funding, human resources, international cooperation and etc. This will be reviewed every five years. This paper is focused on the combining PEST (political, economic, social and technological) method with SWOT (strength, weakness, opportunity and threat) analysis, which is a prerequisite to form national fusion energy technology strategy

  8. Magnetic Resonance Imaging-Ultrasound Fusion-Guided Prostate Biopsy: Review of Technology, Techniques, and Outcomes.

    Science.gov (United States)

    Kongnyuy, Michael; George, Arvin K; Rastinehad, Ardeshir R; Pinto, Peter A

    2016-04-01

    Transrectal ultrasound (TRUS)-guided (12-14 core) systematic biopsy of the prostate is the recommended standard for patients with suspicion of prostate cancer (PCa). Advances in imaging have led to the application of magnetic resonance imaging (MRI) for the detection of PCa with subsequent development of software-based co-registration allowing for the integration of MRI with real-time TRUS during prostate biopsy. A number of fusion-guided methods and platforms are now commercially available with common elements in image and analysis and planning. Implementation of fusion-guided prostate biopsy has now been proven to improve the detection of clinically significant PCa in appropriately selected patients.

  9. Stimulated emission of fast Alfv\\'en waves within magnetically confined fusion plasmas

    CERN Document Server

    Cook, J W S; Chapman, S C

    2016-01-01

    A fast Alfv\\'en wave with finite amplitude is shown to grow by a stimulated emission process that we propose for exploitation in toroidal magnetically confined fusion plasmas. Stimulated emission occurs while the wave propagates inward through the outer mid-plane plasma, where a population inversion of the energy distribution of fusion-born ions is observed to arise naturally. Fully nonlinear first principles simulations, which self-consistently evolve particles and fields under the Maxwell-Lorentz system, demonstrate this novel "alpha-particle channelling" scenario for the first time.

  10. Stimulated Emission of Fast Alfvén Waves within Magnetically Confined Fusion Plasmas

    Science.gov (United States)

    Cook, J. W. S.; Dendy, R. O.; Chapman, S. C.

    2017-05-01

    A fast Alfvén wave with a finite amplitude is shown to grow by a stimulated emission process that we propose for exploitation in toroidal magnetically confined fusion plasmas. Stimulated emission occurs while the wave propagates inward through the outer midplane plasma, where a population inversion of the energy distribution of fusion-born ions is observed to arise naturally. Fully nonlinear first-principles simulations, which self-consistently evolve particles and fields under the Maxwell-Lorentz system, demonstrate this novel "α -particle channeling" scenario for the first time.

  11. Mirror fusion test facility magnet system. Final design report

    Energy Technology Data Exchange (ETDEWEB)

    Henning, C.D.; Hodges, A.J.; VanSant, J.H.; Dalder, E.N.; Hinkle, R.E.; Horvath, J.A.; Scanlan, R.M.; Shimer, D.W.; Baldi, R.W.; Tatro, R.E.

    1980-09-03

    Information is given on each of the following topics: (1) magnet description, (2) superconducting manufacture, (3) mechanical behavior of conductor winding, (4) coil winding, (5) thermal analysis, (6) cryogenic system, (7) power supply system, (8) structural analysis, (9) structural finite element analysis refinement, (10) structural case fault analysis, and (11) structural metallurgy. (MOW)

  12. Spin-off from Euratom-CEA association in fusion magnetic research

    Energy Technology Data Exchange (ETDEWEB)

    Rey, Guy E-mail: guy.rey@cea.fr; Magaud, P.; Libeyre, P.; Garin, P.; Agarici, G.; Beaumont, B.; Berger-by, G.; Bibet, P.; Chappuis, P.; Cordier, J.J.; Couturier, B.; Duchateau, J.L.; Durocher, A.; Escourbiac, F.; Gravil, B.; Kazarian, F.; Lipa, M.; Magne, R.; Portafaix, C.; Schlosser, J

    2003-09-01

    Significant spin-off from magnetic fusion research in Euratom-CEA association, over the last 40 years, has been induced and developed through a continuous process of exchange of scientific, technology and managerial expertise between the fusion scientists and manufacturing engineers. The growth in shared expertise, associated innovative applications and cooperative efforts with industry can be clearly identified (i) in the frame of the European Fusion Development Agreement (EFDA) and underlying technology programme, (ii) by the industrial applications induced from Tore Supra programme and the associated joint development of large test bed facilities for control and acceptance test, (iii) by the appreciation of the expected impacts of ITER from the companies involved in the Tore Supra construction.

  13. Avalanche boron fusion by laser picosecond block ignition with magnetic trapping for clean and economic reactor

    CERN Document Server

    Hora, H; Eliezer, S; Lalousis, N Nissim P; Giuffrida, L; Margarone, D; Picciotto, A; Miley, G H; Moustaizis, S; Martinez-Val, J -M; Barty, C P J; Kirchhoff, G J

    2016-01-01

    After the very long consideration of the ideal energy source by fusion of the protons of light hydrogen with the boron isotope 11 (boron fusion HB11) the very first two independent measurements of very high reaction gains by lasers basically opens a fundamental breakthrough. The non-thermal plasma block ignition with extremely high power laser pulses above petawatt of picosecond duration in combination with up to ten kilotesla magnetic fields for trapping has to be combined to use the measured high gains as proof of an avalanche reaction for an environmentally clean, low cost and lasting energy source as potential option against global warming. The unique HB11 avalanche reaction is are now based on elastic collisions of helium nuclei (alpha particles) limited only to a reactor for controlled fusion energy during a very short time within a very small volume.

  14. Review of heat transfer problems associated with magnetically-confined fusion reactor concepts

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, M.A.; Werner, R.W.; Carlson, G.A.; Cornish, D.N.

    1976-04-01

    Conceptual design studies of possible fusion reactor configurations have revealed a host of interesting and sometimes extremely difficult heat transfer problems. The general requirements imposed on the coolant system for heat removal of the thermonuclear power from the reactor are discussed. In particular, the constraints imposed by the fusion plasma, neutronics, structure and magnetic field environment are described with emphasis on those aspects which are unusual or unique to fusion reactors. Then the particular heat transfer characteristics of various possible coolants including lithium, flibe, boiling alkali metals, and helium are discussed in the context of these general fusion reactor requirements. Some specific areas where further experimental and/or theoretical work is necessary are listed for each coolant along with references to the pertinent research already accomplished. Specialized heat transfer problems of the plasma injection and removal systems are also described. Finally, the challenging heat transfer problems associated with the superconducting magnets are reviewed, and once again some of the key unsolved heat transfer problems are enumerated.

  15. Dust dynamics and diagnostic applications in quasi-neutral plasmas and magnetic fusion

    Science.gov (United States)

    Wang, Zhehui; Ticos, Catalin M.; Si, Jiahe; Delzanno, Gian Luca; Lapenta, Gianni; Wurden, Glen

    2007-11-01

    Little is known about dust dynamics in highly ionized quasi-neutral plasmas with ca. 1.0 e+20 per cubic meter density and ion temperature at a few eV and above, including in magnetic fusion. For example, dust motion in fusion, better known as UFO's, has been observed since 1980's but not explained. Solid understanding of dust dynamics is also important to International Thermonuclear Experimental Reactor (ITER) because of concerns about safety and dust contamination of fusion core. Compared with well studied strongly-coupled dusty plasma regime, new physics may arise in the higher density quasi-neutral plasma regime because of at least four orders of magnitude higher density and two orders of magnitude hotter ion temperature. Our recent laboratory experiments showed that plasma-flow drag force dominates over other forces in a quasi-neutral flowing plasma. In contrast, delicate balance among different forces in dusty plasma has led to many unique phenomena, in particular, the formation of dust crystal. Based on our experiments, we argue that 1) dust crystal will not form in the highly ionized plasmas with flows; 2) the UFO's are moving dust dragged by plasma flows; 3) dust can be used to measure plasma flow. Two diagnostic applications using dust for laboratory quasi-neutral plasmas and magnetic fusion will also be presented.

  16. Picosecond-petawatt laser-block ignition of avalanche boron fusion by ultrahigh acceleration and ultrahigh magnetic fields

    CERN Document Server

    Hora, Heinrich

    2015-01-01

    In contrast to the thermal laser-plasma interaction for fusion by nanosecond pulses, picosecond pulses offer a fundamentally different non-thermal direct conversion of laser energy into ultrahigh acceleration of plasma blocks. This allows to ignite boron fusion which otherwise is most difficult. Trapping by kilotesla magnetic fields and avalanche ignition leads to environmentally clean and economic energy generation.

  17. Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z. X.; Huang, C. J. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR (China); Li, L. F. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, C (China); Li, J. W. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and University of Chinese Academy of Sciences, Beijing 100049, PR (China); Tan, R.; Tu, Y. P. [North China Electric Power University, Beijing 102206, PR (China)

    2014-01-27

    In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical properties of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.

  18. Analyzing large data sets from XGC1 magnetic fusion simulations using apache spark

    Energy Technology Data Exchange (ETDEWEB)

    Churchill, R. Michael [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2016-11-21

    Apache Spark is explored as a tool for analyzing large data sets from the magnetic fusion simulation code XGCI. Implementation details of Apache Spark on the NERSC Edison supercomputer are discussed, including binary file reading, and parameter setup. Here, an unsupervised machine learning algorithm, k-means clustering, is applied to XGCI particle distribution function data, showing that highly turbulent spatial regions do not have common coherent structures, but rather broad, ring-like structures in velocity space.

  19. Soldered joints—an essential component of demountable high temperature superconducting fusion magnets

    Science.gov (United States)

    Tsui, Yeekin; Surrey, Elizabeth; Hampshire, Damian

    2016-07-01

    Demountable superconducting magnet coils would offer significant benefits to commercial nuclear fusion power plants. Whether large pressed joints or large soldered joints provide the solution for demountable fusion magnets, a critical component or building block for both will be the many, smaller-scale joints that enable the supercurrent to leave the superconducting layer, cross the superconducting tape and pass into the solder that lies between the tape and the conductor that eventually provides one of the demountable surfaces. This paper considers the electrical and thermal properties of this essential component part of demountable high temperature superconducting (HTS) joints by considering the fabrication and properties of jointed HTSs consisting of a thin layer of solder (In52Sn48 or Pb38Sn62) sandwiched between two rare-earth-Ba2Cu3O7 (REBCO) second generation HTS coated conductors (CCs). The HTS joints are analysed using numerical modelling, critical current and resistivity measurements on the joints from 300 to 4.2 K in applied magnetic fields up to 12 T, as well as scanning electron microscopy studies. Our results show that the copper/silver layers significantly reduce the heating in the joints to less than a few hundred mK. When the REBCO alone is superconducting, the joint resistivity (R J) predominantly has two sources, the solder layer and an interfacial resistivity at the REBCO/silver interface (∼25 nΩ cm2) in the as-supplied CCs which together have a very weak magnetoresistance in fields up to 12 T. We achieved excellent reproducibility in the R J of the In52Sn48 soldered joints of better than 10% at temperatures below T c of the REBCO layer which can be compared to variations of more than two orders of magnitude in the literature. We also show that demountable joints in fusion energy magnets are viable and need only add a few percent to the total cryogenic cost for a fusion tokamak.

  20. Theoretical Study of Radiation from a Broad Range of Impurity Ions for Magnetic Fusion Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Safronova, Alla [Univ. of Nevada, Reno, NV (United States)

    2014-03-14

    Spectroscopy of radiation emitted by impurities plays an important role in the study of magnetically confined fusion plasmas. The measurements of these impurities are crucial for the control of the general machine conditions, for the monitoring of the impurity levels, and for the detection of various possible fault conditions. Low-Z impurities, typically present in concentrations of 1%, are lithium, beryllium, boron, carbon, and oxygen. Some of the common medium-Z impurities are metals such as iron, nickel, and copper, and high-Z impurities, such as tungsten, are present in smaller concentrations of 0.1% or less. Despite the relatively small concentration numbers, the aforementioned impurities might make a substantial contribution to radiated power, and also influence both plasma conditions and instruments. A detailed theoretical study of line radiation from impurities that covers a very broad spectral range from less than 1 Å to more than 1000 Å has been accomplished and the results were applied to the LLNL Electron Beam Ion Trap (EBIT) and the Sustained Spheromak Physics Experiment (SSPX) and to the National Spherical Torus Experiment (NSTX) at Princeton. Though low- and medium-Z impurities were also studied, the main emphasis was made on the comprehensive theoretical study of radiation from tungsten using different state-of-the-art atomic structure codes such as Relativistic Many-Body Perturbation Theory (RMBPT). The important component of this research was a comparison of the results from the RMBPT code with other codes such as the Multiconfigurational Hartree–Fock developed by Cowan (COWAN code) and the Multiconfiguration Relativistic Hebrew University Lawrence Atomic Code (HULLAC code), and estimation of accuracy of calculations. We also have studied dielectronic recombination, an important recombination process for fusion plasma, for variety of highly and low charged tungsten ions using COWAN and HULLAC codes. Accurate DR rate coefficients are needed for

  1. Proceedings of Brookhaven National Laboratory's fusion/synfuel workshop

    Energy Technology Data Exchange (ETDEWEB)

    Fillo, J.A.; Powell, J.R. (eds.)

    1979-01-01

    The fusion synfuels workshop held at Brookhaven National Laboratory (BNL) on August 27-29, 1979 examined the current status of candidate synfuel processes and the R and D required to develop the capability for fusion synfuel production. Participants divided into five working groups, covering the following areas: (1) economics and applications; (2) high-temperature electrolysis; (3) thermochemical processes (including hybrid thermo-electrochemical); (4) blanket and materials; and (5) high-efficiency power cycles. Each working group presented a summary of their conclusions and recommendations to all participants during the third day of the Workshop. These summaries are given.

  2. Thermal photon production from gluon fusion induced by magnetic fields in relativistic heavy-ion collisions

    CERN Document Server

    Ayala, Alejandro; Dominguez, C A; Hernandez, L A

    2016-01-01

    We compute the production of thermal photons in relativistic heavy-ion collisions by gluon fusion in the presence of an intense magnetic field, and during the early stages of the reaction. This photon yield is an excess over calculations that do not consider magnetic field effects. We add this excess to recent hydrodynamic calculations that are close to describing the experimental transverse momentum distribution in RHIC and LHC. We then show that with reasonable values for the temperature, magnetic field strength, and strong coupling constant, our results provide a very good description of such excess. These results support the idea that the origin of at least some of the photon excess observed in heavy-ion experiments may arise from magnetic field induced processes.

  3. First downscattered neutron images from Inertial Confinement Fusion experiments at the National Ignition Facility

    Directory of Open Access Journals (Sweden)

    Guler Nevzat

    2013-11-01

    Full Text Available Inertial Confinement Fusion experiments at the National Ignition Facility (NIF are designed to understand and test the basic principles of self-sustaining fusion reactions by laser driven compression of deuterium-tritium (DT filled cryogenic plastic (CH capsules. The experimental campaign is ongoing to tune the implosions and characterize the burning plasma conditions. Nuclear diagnostics play an important role in measuring the characteristics of these burning plasmas, providing feedback to improve the implosion dynamics. The Neutron Imaging (NI diagnostic provides information on the distribution of the central fusion reaction region and the surrounding DT fuel by collecting images at two different energy bands for primary (13–15 MeV and downscattered (10–12 MeV neutrons. From these distributions, the final shape and size of the compressed capsule can be estimated and the symmetry of the compression can be inferred. The first downscattered neutron images from imploding ICF capsules are shown in this paper.

  4. Beryllium liner implosion experiments on the Z accelerator in preparation for Magnetized Liner Inertial Fusion (MagLIF)*

    Science.gov (United States)

    McBride, Ryan D.

    2012-10-01

    Magnetized Liner Inertial Fusion (MagLIF) [1] is a concept that involves using a pulsed electrical current to implode an initially-solid, cylindrical metal tube (liner) filled with preheated and magnetized fusion fuel. One- and two-dimensional simulations predict that if sufficient liner integrity can be maintained throughout the implosion, then significant fusion yield (>100 kJ) is possible on the 25-MA, 100-ns Z accelerator. The greatest threat to the liner integrity is the Magneto-Rayleigh-Taylor (MRT) instability, which first develops on the outer liner surface, and then works its way inward toward the inner surface throughout the implosion. Two-dimensional simulations predict that a thick liner, with Router/δR=6, should be robust enough to keep the MRT instability from overly disrupting the fusion burn at stagnation. This talk will present the first experiments designed to study a thick, MagLIF-relevant liner implosion through to stagnation on Z [2]. The use of beryllium for the liner material enabled us to obtain penetrating monochromatic (6151±0.5 eV) radiographs that reveal information about the entire volume of the imploding liner. This talk will also discuss experiments that investigated Z's pulse-shaping capabilities to either shock- or shocklessly-compress the imploding liners [3], as well as our most recent experiments that used 2-micron-thick aluminum sleeves to provide high-contrast tracers for the positions and states of the inner surfaces of the imploding beryllium liners. The radiography data to be presented provide stringent constraints on the simulation tools used by the broader high energy density physics and inertial confinement fusion communities, where quantitative areal density measurements, particularly of convergent fusion targets, are relatively scarce. We will also present power-flow tests of the MagLIF load hardware as well as new micro-B-dot measurements of the azimuthal drive magnetic field that penetrates the initially vacuum

  5. Progress in safety and environmental aspects of inertial fusion energy at Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Latkowski, J F; Reyes, S; Meier, W R

    2000-06-01

    Lawrence Livermore National Laboratory (LLNL) is making significant progress in several areas related to the safety and environmental (S and E) aspects of inertial fusion energy (IFE). A detailed accident analysis has been completed for the HYLIFE-II power plant design. Additional accident analyses are underway for both the HYLIFE-II and Sombrero designs. Other S and E work at LLNL has addressed the issue of the driver-chamber interface and its importance for both heavy-ion and laser-driven IFE. Radiation doses and fluences have been calculated for final focusing mirrors and magnets and shielding optimization is underway to extend the anticipated lifetimes for key components. Target designers/fabrication specialists have been provided with ranking information related to the S and E characteristics of candidate target materials (e.g., ability to recycle, accident consequences, and waste management). Ongoing work in this area will help guide research directions and the selection of target materials. Published and continuing work on fast ignition has demonstrated some of the potentially attractive S and E features of such designs. In addition to reducing total driver energies, fast ignition may ease target fabrication requirements, reduce radiation damage rates, and enable the practical use of advanced (e.g., tritium-lean) labels with significantly reduced neutron production rates, the possibility of self-breeding targets, and dramatically increased flexibility in blanket design. Domestic and international collaborations are key to success in the above areas. A brief summary of each area is given and plans for future work are outlined.

  6. Fifty Years of Magnetic Fusion Research (1958–2008: Brief Historical Overview and Discussion of Future Trends

    Directory of Open Access Journals (Sweden)

    Laila A. El-Guebaly

    2010-06-01

    Full Text Available Fifty years ago, the secrecy surrounding magnetically controlled thermonuclear fusion had been lifted allowing researchers to freely share technical results and discuss the challenges of harnessing fusion power. There were only four magnetic confinement fusion concepts pursued internationally: tokamak, stellarator, pinch, and mirror. Since the early 1970s, numerous fusion designs have been developed for the four original and three new approaches: spherical torus, field-reversed configuration, and spheromak. At present, the tokamak is regarded worldwide as the most viable candidate to demonstrate fusion energy generation. Numerous power plant studies (>50, extensive R&D programs, more than 100 operating experiments, and an impressive international collaboration led to the current wealth of fusion information and understanding. As a result, fusion promises to be a major part of the energy mix in the 21st century. The fusion roadmaps developed to date take different approaches, depending on the anticipated power plant concept and the degree of extrapolation beyond ITER. Several Demos with differing approaches will be built in the US, EU, Japan, China, Russia, Korea, India, and other countries to cover the wide range of near-term and advanced fusion systems.

  7. Summary of the report of the Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy

    Energy Technology Data Exchange (ETDEWEB)

    Holdren, J.P.; Berwald, D.H.; Budnitz, R.J.; Crocker, J.G.; Delene, J.G.; Endicott, R.D.; Kazimi, M.S.; Krakowski, R.A.; Logan, B.G.; Schultz, K.R.

    1987-09-10

    The Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (ESECOM) has assessed magnetic fusion energy's prospects for providing energy with economic, environmental, and safety characteristics that would be attractive compared with other energy sources (mainly fission) available in the year 2015 and beyond. ESECOM gives particular attention to the interaction of environmental, safety, and economic characteristics of a variety of magnetic fusion reactors, and compares them with a variety of fission cases. Eight fusion cases, two fusion-fission hybrid cases, and four fission cases are examined, using consistent economic and safety models. These models permit exploration of the environmental, safety, and economic potential of fusion concepts using a wide range of possible materials choices, power densities, power conversion schemes, and fuel cycles. The ESECOM analysis indicates that magnetic fusion energy systems have the potential to achieve costs-of-electricity comparable to those of present and future fission systems, coupled with significant safety and environmental advantages. 75 refs., 2 figs., 24 tabs.

  8. Assessing the Performance of Sensor Fusion Methods: Application to Magnetic-Inertial-Based Human Body Tracking

    Directory of Open Access Journals (Sweden)

    Gabriele Ligorio

    2016-01-01

    Full Text Available Information from complementary and redundant sensors are often combined within sensor fusion algorithms to obtain a single accurate observation of the system at hand. However, measurements from each sensor are characterized by uncertainties. When multiple data are fused, it is often unclear how all these uncertainties interact and influence the overall performance of the sensor fusion algorithm. To address this issue, a benchmarking procedure is presented, where simulated and real data are combined in different scenarios in order to quantify how each sensor’s uncertainties influence the accuracy of the final result. The proposed procedure was applied to the estimation of the pelvis orientation using a waist-worn magnetic-inertial measurement unit. Ground-truth data were obtained from a stereophotogrammetric system and used to obtain simulated data. Two Kalman-based sensor fusion algorithms were submitted to the proposed benchmarking procedure. For the considered application, gyroscope uncertainties proved to be the main error source in orientation estimation accuracy for both tested algorithms. Moreover, although different performances were obtained using simulated data, these differences became negligible when real data were considered. The outcome of this evaluation may be useful both to improve the design of new sensor fusion methods and to drive the algorithm tuning process.

  9. Assessing the Performance of Sensor Fusion Methods: Application to Magnetic-Inertial-Based Human Body Tracking.

    Science.gov (United States)

    Ligorio, Gabriele; Bergamini, Elena; Pasciuto, Ilaria; Vannozzi, Giuseppe; Cappozzo, Aurelio; Sabatini, Angelo Maria

    2016-01-26

    Information from complementary and redundant sensors are often combined within sensor fusion algorithms to obtain a single accurate observation of the system at hand. However, measurements from each sensor are characterized by uncertainties. When multiple data are fused, it is often unclear how all these uncertainties interact and influence the overall performance of the sensor fusion algorithm. To address this issue, a benchmarking procedure is presented, where simulated and real data are combined in different scenarios in order to quantify how each sensor's uncertainties influence the accuracy of the final result. The proposed procedure was applied to the estimation of the pelvis orientation using a waist-worn magnetic-inertial measurement unit. Ground-truth data were obtained from a stereophotogrammetric system and used to obtain simulated data. Two Kalman-based sensor fusion algorithms were submitted to the proposed benchmarking procedure. For the considered application, gyroscope uncertainties proved to be the main error source in orientation estimation accuracy for both tested algorithms. Moreover, although different performances were obtained using simulated data, these differences became negligible when real data were considered. The outcome of this evaluation may be useful both to improve the design of new sensor fusion methods and to drive the algorithm tuning process.

  10. The Science and Technology Challenges of the Plasma-Material Interface for Magnetic Fusion Energy

    Science.gov (United States)

    Whyte, Dennis

    2013-09-01

    The boundary plasma and plasma-material interactions of magnetic fusion devices are reviewed. The boundary of magnetic confinement devices, from the high-temperature, collisionless pedestal through to the surrounding surfaces and the nearby cold high-density collisional plasmas, encompasses an enormous range of plasma and material physics, and their integrated coupling. Due to fundamental limits of material response the boundary will largely define the viability of future large MFE experiments (ITER) and reactors (e.g. ARIES designs). The fusion community faces an enormous knowledge deficit in stepping from present devices, and even ITER, towards fusion devices typical of that required for efficient energy production. This deficit will be bridged by improving our fundamental science understanding of this complex interface region. The research activities and gaps are reviewed and organized to three major axes of challenges: power density, plasma duration, and material temperature. The boundary can also be considered a multi-scale system of coupled plasma and material science regulated through the non-linear interface of the sheath. Measurement, theory and modeling across these scales are reviewed, with a particular emphasis on establishing the use dimensionless parameters to understand this complex system. Proposed technology and science innovations towards solving the PMI/boundary challenges will be examined. Supported by US DOE award DE-SC00-02060 and cooperative agreement DE-FC02-99ER54512.

  11. Magnet design with 100-kA HTS STARS conductors for the helical fusion reactor

    Science.gov (United States)

    Yanagi, N.; Terazaki, Y.; Ito, S.; Tamura, H.; Hamaguchi, S.; Mito, T.; Hashizume, H.; Sagara, A.

    2016-12-01

    The high-temperature superconducting (HTS) option is employed for the conceptual design of the LHD-type helical fusion reactor FFHR-d1. The 100-kA-class STARS (Stacked Tapes Assembled in Rigid Structure) conductor is used for the magnet system including the continuously wound helical coils. Protection of the magnet system in case of a quench is a crucial issue and the hot-spot temperature during an emergency discharge is estimated based on the zero-dimensional and one-dimensional analyses. The number of division of the coil winding package is examined to limit the voltage generation. For cooling the HTS magnet, helium gas flow is considered and its feasibility is examined by simple analysis as a first step.

  12. Fusion of structural and functional cardiac magnetic resonance imaging data for studying ventricular fibrillation.

    Science.gov (United States)

    Magtibay, K; Beheshti, M; Foomany, F H; Balasundaram, K; Masse, S; Lai, P; Asta, J; Zamiri, N; Jaffray, D A; Nanthakumar, K; Krishnan, S; Umapathy, K

    2014-01-01

    Magnetic Resonance Imaging (MRI) techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) provide a complementing set of imaging data that can describe both the functional and structural states of biological tissues. This paper presents a Joint Independent Component Analysis (jICA) based fusion approach which can be utilized to fuse CDI and DTI data to quantify the differences between two cardiac states: Ventricular Fibrillation (VF) and Asystolic/Normal (AS/NM). Such an approach could lead to a better insight on the mechanism of VF. Fusing CDI and DTI data from 8 data sets from 6 beating porcine hearts, in effect, detects the differences between two cardiac states, qualitatively and quantitatively. This initial study demonstrates the applicability of MRI-based imaging techniques and jICA-based fusion approach in studying cardiac arrhythmias.

  13. The Potential Use of Ultrasound-Magnetic Resonance Imaging Fusion Applications in Musculoskeletal Intervention.

    Science.gov (United States)

    Burke, Christopher J; Bencardino, Jenny; Adler, Ronald

    2017-01-01

    We sought to assess the potential use of an application allowing real-time ultrasound spatial registration with previously acquired magnetic resonance imaging in musculoskeletal procedures. The ultrasound fusion application was used to perform a range of outpatient procedures including piriformis, sacroiliac joint, pudendal and intercostal nerve perineurial injections, hamstring-origin calcific tendonopathy barbotage, and 2 soft tissue biopsies at our institution in 2015. The application was used in a total of 7 procedures in 7 patients, all of which were technically successful. The ages of patients ranged from 19 to 86 years. Particular use of the fusion application compared to sonography alone was noted in the biopsy of certain soft tissue lesions and in perineurial therapeutic injections. © 2016 by the American Institute of Ultrasound in Medicine.

  14. Existing and new applications of micropellet injection (MPI) in magnetic fusion

    Science.gov (United States)

    Wang, Zhehui; Lunsford, Robert; Mansfield, Dennis K.; Nichols, Jacob H.

    2016-04-01

    > The intense heat and energetic particle fluxes expected in ITER and future magnetic fusion reactors pose prohibitive problems to the design, selection and maintenance of the first wall and divertor. Micropellet injection (MPI) technologies can offer some innovative solutions to the material and extreme heat challenges. Basic physics of micropellet motion, ablation and interactions with high-temperature plasmas and energetic particles are presented first. We then discuss MPI technology options and applications. In addition to plasma diagnostic applications, controlled injection of micropellets of different sizes, velocities and injection frequencies will offer several possibilities: (1) better assessment of the core plasma cooling due to dust produced in situ; (2) better understanding of the plasma-material interaction physics near the wall; (3) new methods for plasma fuelling and impurity control; and (4) techniques for edge cooling with minimal impact on the plasma core. Dedicated small-scale laboratory experiments will complement major fusion experiments in development and applications of MPI.

  15. Study of Plasma Liner Driven Magnetized Target Fusion Via Advanced Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Samulyak, Roman V. [State Univ. of New York (SUNY), Stony Brook, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States); Parks, Paul [General Atomics, San Diego, CA (United States)

    2013-08-31

    The feasibility of the plasma liner driven Magnetized Target Fusion (MTF) via terascale numerical simulations will be assessed. In the MTF concept, a plasma liner, formed by merging of a number (60 or more) of radial, highly supersonic plasma jets, implodes on the target in the form of two compact plasma toroids, and compresses it to conditions of the fusion ignition. By avoiding major difficulties associated with both the traditional laser driven inertial confinement fusion and solid liner driven MTF, the plasma liner driven MTF potentially provides a low-cost and fast R&D path towards the demonstration of practical fusion energy. High fidelity numerical simulations of full nonlinear models associated with the plasma liner MTF using state-of-art numerical algorithms and terascale computing are necessary in order to resolve uncertainties and provide guidance for future experiments. At Stony Brook University, we have developed unique computational capabilities that ideally suite the MTF problem. The FronTier code, developed in collaboration with BNL and LANL under DOE funding including SciDAC for the simulation of 3D multi-material hydro and MHD flows, has beenbenchmarked and used for fundamental and engineering problems in energy science applications. We have performed 3D simulations of converging supersonic plasma jets, their merger and the formation of the plasma liner, and a study of the corresponding oblique shock problem. We have studied the implosion of the plasma liner on the magnetized plasma target by resolving Rayleigh-Taylor instabilities in 2D and 3D and other relevant physics and estimate thermodynamic conditions of the target at the moment of maximum compression and the hydrodynamic efficiency of the method.

  16. The in-situ diagnosis of plasma-wall interactions on magnetic fusion devices with accelerators

    Science.gov (United States)

    Hartwig, Zachary

    2013-10-01

    We present the first in-situ, time-resolved measurements of low-Z isotope composition and deuterium retention over a large plasma-facing component (PFC) surface area in a magnetic fusion device. These critical measurements were made using a novel diagnostic technique based on the analysis of induced nuclear reactions from PFC surfaces on the Alcator C-Mod tokamak. Achieving an integrated understanding of plasma physics and materials science in magnetic fusion devices is severely hindered by a dearth of in-situ PFC surface diagnosis. Plasma-wall interactions, such as the erosion/redeposition of PFC material, the evolution of PFC surface isotope composition, and fusion fuel retention present significant plasma physics and materials science challenges for long pulse or steady-state devices. Our diagnostic uses a compact (~1 meter), high-current (~1 milliamp) radio-frequency quadrupole accelerator to inject ~1 MeV deuterons into the vacuum vessel. We control the tokamak's magnetic fields - in between plasma shots - to steer the deuterons to PFC surfaces, where they induce high-Q nuclear reactions with low-Z isotopes in the first ~10 microns of material. Analysis of the induced gamma and neutron energy spectra provides quantitative reconstruction of PFC surface conditions. This nondestructive, in-situ technique achieves PFC surface composition measurements with plasma shot-to-shot time resolution and 1 centimeter spatial resolution over large PFC areas. Work supported by U.S. DOE Grant DE-FG02-94ER54235 and Cooperative Agreement DE-FC02-99ER54512.

  17. Helium mass flow measurement in the International Fusion Superconducting Magnet Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Baylor, L.R.

    1986-08-01

    The measurement of helium mass flow in the International Fusion Superconducting Magnet Test Facility (IFSMTF) is an important aspect in the operation of the facility's cryogenic system. Data interpretation methods that lead to inaccurate results can cause severe difficulty in controlling the experimental superconducting coils being tested in the facility. This technical memorandum documents the methods of helium mass flow measurement used in the IFSMTF for all participants of the Large Coil Program and for other cryogenic experimentalists needing information on mass flow measurements. Examples of experimental data taken and calculations made are included to illustrate the applicability of the methods used.

  18. Exploring magnetized liner inertial fusion with a semi-analytic model

    OpenAIRE

    R. D. McBride; Slutz, S. A.; Vesey, R. A.; Gomez, M. R.; Sefkow, A.B.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Geissel, M.; Harvey-Thompson, A. J.; Jennings, C. A.; Harding, E. C.; Awe, T. J.; Rovang, D. C.; Hahn, K D

    2015-01-01

    In this paper, we explore magnetized liner inertial fusion (MagLIF) [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] using a semi-analytic model [R. D. McBride and S. A. Slutz, Phys. Plasmas 22, 052708 (2015)]. Specifically, we present simulation results from this model that: (a) illustrate the parameter space, energetics, and overall system efficiencies of MagLIF; (b) demonstrate the dependence of radiative loss rates on the radial fraction of the fuel that is preheated; (c) explore som...

  19. Adaptability of optimization concept in the context of cryogenic distribution for superconducting magnets of fusion machine

    Science.gov (United States)

    Sarkar, Biswanath; Bhattacharya, Ritendra Nath; Vaghela, Hitensinh; Shah, Nitin Dineshkumar; Choukekar, Ketan; Badgujar, Satish

    2012-06-01

    Cryogenic distribution system (CDS) plays a vital role for reliable operation of largescale fusion machines in a Tokamak configuration. Managing dynamic heat loads from the superconducting magnets, namely, toroidal field, poloidal field, central solenoid and supporting structure is the most important function of the CDS along with the static heat loads. Two concepts are foreseen for the configuration of the CDS: singular distribution and collective distribution. In the first concept, each magnet is assigned with one distribution box having its own sub-cooler bath. In the collective concept, it is possible to share one common bath for more than one magnet system. The case study has been performed with an identical dynamic heat load profile applied to both concepts in the same time domain. The choices of a combined system from the magnets are also part of the study without compromising the system functionality. Process modeling and detailed simulations have been performed for both the options using Aspen HYSYS®. Multiple plasma pulses per day have been considered to verify the residual energy deposited in the superconducting magnets at the end of the plasma pulse. Preliminary 3D modeling using CATIA® has been performed along with the first level of component sizing.

  20. Position control of active magnetic levitation using sphere-shaped HTS bulk for inertial nuclear fusion

    Science.gov (United States)

    Suga, K.; Riku, K.; Agatsuma, K.; Ueda, H.; Ishiyama, A.

    2008-02-01

    We have developed an active magnetic levitation system that comprises a field-cooled disk-shaped or sphere-shaped HTS bulk and multiple ring-shaped electromagnets. In this system, the levitation height of HTS bulk can be controlled by adjusting the operating current of each electromagnet individually. Further, the application of the vertical noncontact levitation system is expected due to its levitation stability without mechanical supports. We assume that this system is applied to inertial nuclear fusion. However, one of the important issues is to achieve position control with high accuracy of the fusion fuel in order to illuminate the target evenly over the entire surface. Therefore, this system is applied to the levitation and position control of a sphere-shaped superconducting capsule containing nuclear fusion fuel. In this study, we designed and constructed a position control system for the sphere-shaped HTS bulk with a diameter of 5 mm by using numerical simulation based on hybrid finite element and boundary element analysis. We then carried out the experiment of levitation height and position control characteristics of the HTS bulk in this system. With regard to position control, accuracies within 59 ?m are obtained.

  1. Characterization of high temperature superconductor cables for magnet toroidal field coils of the DEMO fusion power plant

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, Christoph M.

    2017-05-01

    Nuclear fusion is a key technology to satisfy the basic demand for electric energy sustainably. The official EUROfusion schedule foresees a first industrial DEMOnstration Fusion Power Plant for 2050. In this work several high temperature superconductor sub-size cables are investigated for their applicability in large scale DEMO toroidal field coils. Main focus lies on the electromechanical stability under the influence of high Lorentz forces at peak magnetic fields of up to 12 T.

  2. Need for development of higher strength cryogenic structural materials for fusion magnet

    Science.gov (United States)

    Nishimura, Arata

    2014-01-01

    A prototype fusion reactor is targeted as a beyond ITER project which is so called DEMO. Several conceptual designs have been carried out. Recently, in order to recognize practical aspects on maintenance of the prototype reactor, the replacement procedure of in-vessel components was focused and "sector process" was proposed. The process is that the reactor consists of sectors and all sectors will be drowned and replaced in a short time. The slim coil which generated higher magnetic field is required to realize the sector process. From the point of coil design, the occupancy of the structural material on the cross section of the coil increases with an increase of magnetic field. To realize the slim coil, the cryogenic structural material with higher yield strength and the proper toughness is desired.

  3. The National Ignition Facility: Enabling Fusion Ignition for the 21st Century

    Energy Technology Data Exchange (ETDEWEB)

    Moses, E I; Miller, G H; Wuest, C R

    2004-09-17

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, when completed in 2008, will contain a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter-diameter target chamber and room for 100 diagnostics. NIF is housed in a 26,000 square meter environmentally controlled building and is the world's largest and most energetic laser experimental system. NIF provides a scientific center for the study of inertial confinement fusion and the physics of matter at extreme energy densities and pressures. NIF's energetic laser beams will compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. Other NIF experiments will study physical processes at temperatures approaching 10{sup 8} K and 10{sup 11} bar; conditions that exist naturally only in the interior of stars and planets. NIF is currently configured with four laser beams activated in late 2002. These beams are being regularly used for laser performance and physics experiments and to date nearly 250 system shots have been conducted. NIF's laser beams have generated 106 kilojoules in 23-ns pulses of infrared light and over 16 kJ in 3.5-ns pulses at the third harmonic (351 nm). A number of target experimental systems are being commissioned in support of experimental campaigns. This paper provides a detailed look the NIF laser systems, laser and optical performance, and results from laser commissioning shots. We also discuss NIF's high -energy density and inertial fusion experimental capabilities, the first experiments on NIF, and plans for future capabilities of this unique facility.

  4. The National Ignition Facility and the Promise of Inertial Fusion Energy

    Energy Technology Data Exchange (ETDEWEB)

    Moses, E I

    2010-12-13

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is now operational. The NIF is the world's most energetic laser system capable of producing 1.8 MJ and 500 TW of ultraviolet light. By concentrating the energy from its 192 extremely energetic laser beams into a mm{sup 3}-sized target, NIF can produce temperatures above 100 million K, densities of 1,000 g/cm{sup 3}, and pressures 100 billion times atmospheric pressure - conditions that have never been created in a laboratory and emulate those in planetary interiors and stellar environments. On September 29, 2010, the first integrated ignition experiment was conducted, demonstrating the successful coordination of the laser, cryogenic target system, array of diagnostics and infrastructure required for ignition demonstration. In light of this strong progress, the U.S. and international communities are examining the implication of NIF ignition for inertial fusion energy (IFE). A laser-based IFE power plant will require a repetition rate of 10-20 Hz and a laser with 10% electrical-optical efficiency, as well as further development and advances in large-scale target fabrication, target injection, and other supporting technologies. These capabilities could lead to a prototype IFE demonstration plant in the 10- to 15-year time frame. LLNL, in partnership with other institutions, is developing a Laser Inertial Fusion Engine (LIFE) concept and examining in detail various technology choices, as well as the advantages of both pure fusion and fusion-fission schemes. This paper will describe the unprecedented experimental capabilities of the NIF and the results achieved so far on the path toward ignition. The paper will conclude with a discussion about the need to build on the progress on NIF to develop an implementable and effective plan to achieve the promise of LIFE as a source of carbon-free energy.

  5. Variability in Standard Outcomes of Posterior Lumbar Fusion Determined by National Databases.

    Science.gov (United States)

    Joseph, Jacob R; Smith, Brandon W; Park, Paul

    2017-01-01

    National databases are used with increasing frequency in spine surgery literature to evaluate patient outcomes. The differences between individual databases in relationship to outcomes of lumbar fusion are not known. We evaluated the variability in standard outcomes of posterior lumbar fusion between the University HealthSystem Consortium (UHC) database and the Healthcare Cost and Utilization Project National Inpatient Sample (NIS). NIS and UHC databases were queried for all posterior lumbar fusions (International Classification of Diseases, Ninth Revision code 81.07) performed in 2012. Patient demographics, comorbidities (including obesity), length of stay (LOS), in-hospital mortality, and complications such as urinary tract infection, deep venous thrombosis, pulmonary embolism, myocardial infarction, durotomy, and surgical site infection were collected using specific International Classification of Diseases, Ninth Revision codes. Analysis included 21,470 patients from the NIS database and 14,898 patients from the UHC database. Demographic data were not significantly different between databases. Obesity was more prevalent in UHC (P = 0.001). Mean LOS was 3.8 days in NIS and 4.55 in UHC (P databases. NIS and UHC databases had similar demographic patient populations undergoing posterior lumbar fusion. However, the UHC database reported significantly higher complication rate and longer LOS. This difference may reflect academic institutions treating higher-risk patients; however, a definitive reason for the variability between databases is unknown. The inability to precisely determine the basis of the variability between databases highlights the limitations of using administrative databases for spinal outcome analysis. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Solid-State Nuclear Magnetic Resonance Investigation of the Structural Topology and Lipid Interactions of a Viral Fusion Protein Chimera Containing the Fusion Peptide and Transmembrane Domain.

    Science.gov (United States)

    Yao, Hongwei; Lee, Myungwoon; Liao, Shu-Yu; Hong, Mei

    2016-12-13

    The fusion peptide (FP) and transmembrane domain (TMD) of viral fusion proteins play important roles during virus-cell membrane fusion, by inducing membrane curvature and transient dehydration. The structure of the water-soluble ectodomain of viral fusion proteins has been extensively studied crystallographically, but the structures of the FP and TMD bound to phospholipid membranes are not well understood. We recently investigated the conformations and lipid interactions of the separate FP and TMD peptides of parainfluenza virus 5 (PIV5) fusion protein F using solid-state nuclear magnetic resonance. These studies provide structural information about the two domains when they are spatially well separated in the fusion process. To investigate how these two domains are structured relative to each other in the postfusion state, when the ectodomain forms a six-helix bundle that is thought to force the FP and TMD together in the membrane, we have now expressed and purified a chimera of the FP and TMD, connected by a Gly-Lys linker, and measured the chemical shifts and interdomain contacts of the protein in several lipid membranes. The FP-TMD chimera exhibits α-helical chemical shifts in all the membranes examined and does not cause strong curvature of lamellar membranes or membranes with negative spontaneous curvature. These properties differ qualitatively from those of the separate peptides, indicating that the FP and TMD interact with each other in the lipid membrane. However, no (13)C-(13)C cross peaks are observed in two-dimensional correlation spectra, suggesting that the two helices are not tightly associated. These results suggest that the ectodomain six-helix bundle does not propagate into the membrane to the two hydrophobic termini. However, the loosely associated FP and TMD helices are found to generate significant negative Gaussian curvature to membranes that possess spontaneous positive curvature, consistent with the notion that the FP-TMD assembly may

  7. Considerations of the high magnetic field tokamak path on the approach to fusion energy

    Science.gov (United States)

    Marmar, Earl

    2015-11-01

    This tutorial will review the physics basis, and its applications, for high magnetic field, compact visions of steady-state pilot plants and fusion reactors. This includes: energy and particle confinement; transport barriers; heating and current drive; scrape-off layer and divertor physics including implications for power handling, and ash/impurity control. The development of new technologies, particularly high-temperature, high critical magnetic field superconducting materials opens a new opportunity to consider the leverage of on-axis magnetic fields of 10T or more, enabling the feasibility of smaller sized devices on the path to fusion energy, including a pilot plant which could produce hundreds of megawatts of net electricity in a 10T tokamak with major radius of order 3 meter. Incorporating jointed magnetic coils, also made feasible by the high temperature superconductors, can dramatically improve flexibility of experimental superconducting facilities, and ultimately maintainability for reactor systems. Steady-state requires high bootstrap fraction, combined with efficient off-axis current drive, and existing and new approaches for RF sustainment will be covered, including Lower Hybrid Current Drive (both from the low- and high-field side), ECCD, and fast-wave techniques. External torque drive from neutral beams, routinely used in most present-day experiments to enhance confinement and suppress instabilities, will be weak or absent in reactors. Alternative, RF-based flow drive, using mode-converted ICRF waves will be discussed. All reactor concepts have extraordinary power handling requirements, combined with stringent limits on PFC erosion and impurity sources; the current state of the art in divertor configurations will be compared with emerging and new concepts, including snowflake, x-point, x-divertor and liquid metals, to meet these challenges. Supported by USDOE.

  8. Nonperturbative measurement of the local magnetic field using pulsed polarimetry for fusion reactor conditions (invited).

    Science.gov (United States)

    Smith, Roger J

    2008-10-01

    A novel diagnostic technique for the remote and nonperturbative sensing of the local magnetic field in reactor relevant plasmas is presented. Pulsed polarimetry [Patent No. 12/150,169 (pending)] combines optical scattering with the Faraday effect. The polarimetric light detection and ranging (LIDAR)-like diagnostic has the potential to be a local B(pol) diagnostic on ITER and can achieve spatial resolutions of millimeters on high energy density (HED) plasmas using existing lasers. The pulsed polarimetry method is based on nonlocal measurements and subtle effects are introduced that are not present in either cw polarimetry or Thomson scattering LIDAR. Important features include the capability of simultaneously measuring local T(e), n(e), and B(parallel) along the line of sight, a resiliency to refractive effects, a short measurement duration providing near instantaneous data in time, and location for real-time feedback and control of magnetohydrodynamic (MHD) instabilities and the realization of a widely applicable internal magnetic field diagnostic for the magnetic fusion energy program. The technique improves for higher n(e)B(parallel) product and higher n(e) and is well suited for diagnosing the transient plasmas in the HED program. Larger devices such as ITER and DEMO are also better suited to the technique, allowing longer pulse lengths and thereby relaxing key technology constraints making pulsed polarimetry a valuable asset for next step devices. The pulsed polarimetry technique is clarified by way of illustration on the ITER tokamak and plasmas within the magnetized target fusion program within present technological means.

  9. Scaling magnetized liner inertial fusion on Z and future pulsed-power accelerators

    Science.gov (United States)

    Slutz, S. A.; Stygar, W. A.; Gomez, M. R.; Peterson, K. J.; Sefkow, A. B.; Sinars, D. B.; Vesey, R. A.; Campbell, E. M.; Betti, R.

    2016-02-01

    The MagLIF (Magnetized Liner Inertial Fusion) concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] has demonstrated fusion-relevant plasma conditions [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z accelerator with a peak drive current of about 18 MA. We present 2D numerical simulations of the scaling of MagLIF on Z as a function of drive current, preheat energy, and applied magnetic field. The results indicate that deuterium-tritium (DT) fusion yields greater than 100 kJ could be possible on Z when all of these parameters are at the optimum values: i.e., peak current = 25 MA, deposited preheat energy = 5 kJ, and Bz = 30 T. Much higher yields have been predicted [S. A. Slutz and R. A. Vesey, Phys. Rev. Lett. 108, 025003 (2012)] for MagLIF driven with larger peak currents. Two high performance pulsed-power accelerators (Z300 and Z800) based on linear-transformer-driver technology have been designed [W. A. Stygar et al., Phys. Rev. ST Accel. Beams 18, 110401 (2015)]. The Z300 design would provide 48 MA to a MagLIF load, while Z800 would provide 65 MA. Parameterized Thevenin-equivalent circuits were used to drive a series of 1D and 2D numerical MagLIF simulations with currents ranging from what Z can deliver now to what could be achieved by these conceptual future pulsed-power accelerators. 2D simulations of simple MagLIF targets containing just gaseous DT have yields of 18 MJ for Z300 and 440 MJ for Z800. The 2D simulated yield for Z800 is increased to 7 GJ by adding a layer of frozen DT ice to the inside of the liner.

  10. Prompt photon yield and elliptic flow from gluon fusion induced by magnetic fields in relativistic heavy-ion collisions

    Science.gov (United States)

    Ayala, Alejandro; Castaño-Yepes, Jorge David; Dominguez, C. A.; Hernández, L. A.; Hernández-Ortiz, Saúl; Tejeda-Yeomans, María Elena

    2017-07-01

    We compute photon production at early times in semicentral relativistic heavy-ion collisions from nonequilibrium gluon fusion induced by a magnetic field. The calculation accounts for the main features of the collision at these early times, namely, the intense magnetic field and the high gluon occupation number. The gluon fusion channel is made possible by the magnetic field and would otherwise be forbidden due to charge conjugation invariance. Thus, the photon yield from this process is an excess over calculations without magnetic field effects. We compare this excess to the difference between PHENIX data and recent hydrodynamic calculations for the photon transverse momentum distribution and elliptic flow coefficient v2 . We show that with reasonable values for the saturation scale and magnetic field strength, the calculation helps us better describe the experimental results obtained at RHIC energies for the lowest part of the transverse photon momentum.

  11. High field magnet program at Brookhaven National Laboratory

    CERN Document Server

    Ghosh, A; Muratore, J; Parker, B; Sampson, W; Wanderer, P J; Willen, E

    2000-01-01

    The magnet program at Brookhaven National Laboratory (BNL) is focussed on superconducting magnets for particle accelerators. The effort includes magnet production at the laboratory and in industry, magnet R&D, and test facilities for magnets and superconductors. Nearly 2000 magnets-dipoles, quadrupoles, sextupoles and correctors for the arc and insertion regions-were produced for the Relativistic Heavy Ion Collider (RHIC), which is being commissioned. Currently, production of helical dipoles for the polarized proton program at RHIC, insertion region dipoles for the Large Hadron Collider (LHC) at CERN, and an insertion magnet system for the Hadron-Elektron-Ring- Analage (HERA) collider at Deutsches Elektronen-Synchrotron (DESY) is underway. The R&D effort is exploring dipoles with fields above 10 T for use in post-LHC colliders. Brittle superconductors-Nb/sub 3/Sn or HTS-are being used for these magnets. The superconductor test facility measures short-sample currents and other characteristics of sample...

  12. High-power-density approaches to magnetic fusion energy: Problems and promise of compact reversed-field pinch reactors (CRFPR)

    Science.gov (United States)

    Hagenson, Randy L.; Krakowski, Robert A.; Dreicer, Harry

    1983-03-01

    If the costing assumptions upon which the positive assessment of conventional large superconducting fusion reactors are based proves overly optimistic, approaches that promise considerably increased system power density and reduced mass utilization will be required. These more compact reactor embodiments generally must operate with reduced shield thickness and resistive magnets. Because of the unique magnetic topology associated with the Reversed-Field Pinch (RFP), the compact reactor embodiment for this approach is particularly attractive from the viewpoint of low-field resistive coils operating with ohmic losses that can be made small relative to the fusion power. The RFP, therefore, is used as one example of a high-power-density (HPD) approach to magnetic fusion energy. A comprehensive system model is described and applied to select a unique, cost-optimized design point that will be used for a subsequent conceptual engineering design of the compact RFP Reactor (CRFPR). This cost-optimized CRFPR design serves as an example of a HPD fusion reactor that would operate with system power densities and mass utilizations that are comparable to fission power plants, these measures of system performance being an order of magnitude more favorable than the conventional approaches to magnetic fusion energy (MFE).

  13. Mutagenesis and nuclear magnetic resonance analyses of the fusion peptide of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus F protein.

    Science.gov (United States)

    Tan, Ying; Jiang, Ling; Wang, Manli; Yin, Feifei; Deng, Fei; Liu, Maili; Hu, Zhihong; Wang, Hualin

    2008-08-01

    The entry of enveloped viruses into cells is normally mediated by fusion between viral and cellular membranes, in which the fusion peptide plays a crucial role. The fusion peptides of group II nucleopolyhedrovirus (NPV) F proteins are quite conserved, with a hydrophobic region located at the N terminal of the F(1) fragment. For this report, we used mutagenesis and nuclear magnetic resonance (NMR) to study the structure and function of the fusion peptide of the Helicoverpa armigera single-nucleocapsid NPV (HearNPV) F protein (HaF). Five mutations in the fusion peptide of HaF, N(1)G, N(1)L, I(2)N, G(3)L, and D(11)L, were generated separately, and the mutated f genes were transformed into the f-null HearNPV bacmid. The mutations N(1)L, I(2)N, and D(11)L were found to completely abolish the ability of the recombinant bacmids to produce infectious budded virus, while the mutations N(1)G and G(3)L did not. The low-pH-induced envelope fusion assay demonstrated that the N(1)G substitution increased the fusogenicity of HaF, while the G(3)L substitution reduced its fusogenicity. NMR spectroscopy was used to determine the structure of a synthetic fusion peptide of HaF in the presence of sodium dodecyl sulfate micelles at pH 5.0. The fusion peptide appeared to be an amphiphilic structure composed of a flexible coil in the N terminus from N(1) to N(5), a 3(10)-helix from F(6) to G(8), a turn at S(9), and a regular alpha-helix from V(10) to D(19). The data provide the first NMR structure of a baculovirus fusion peptide and allow us to further understand the relationship of structure and function of the fusion peptide.

  14. Fusion Policy Advisory Committee (FPAC)

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This document is the final report of the Fusion Policy Advisory Committee. The report conveys the Committee's views on the matters specified by the Secretary in his charge and subsequent letters to the Committee, and also satisfies the provisions of Section 7 of the Magnetic Fusion Energy Engineering Act of 1980, Public Law 96-386, which require a triennial review of the conduct of the national Magnetic Fusion Energy program. Three sub-Committee's were established to address the large number of topics associated with fusion research and development. One considered magnetic fusion energy, a second considered inertial fusion energy, and the third considered issues common to both. For many reasons, the promise of nuclear fusion as a safe, environmentally benign, and affordable source of energy is bright. At the present state of knowledge, however, it is uncertain that this promise will become reality. Only a vigorous, well planned and well executed program of research and development will yield the needed information. The Committee recommends that the US commit to a plan that will resolve this critically important issue. It also outlines the first steps in a development process that will lead to a fusion Demonstration Power Plant by 2025. The recommended program is aggressive, but we believe the goal is reasonable and attainable. International collaboration at a significant level is an important element in the plan.

  15. Magnetic resonance imaging on disc degeneration changes after implantation of an interspinous spacer and fusion of the adjacent segment.

    Science.gov (United States)

    Liu, Xiaokang; Liu, Yingjie; Lian, Xiaofeng; Xu, Jianguang

    2015-01-01

    The aim of the study was to investigate the changes of the lumbar intervertebral disc degeneration by magnetic resonance imaging (MRI) after the implantation of interspinous device and the fusion of the adjacent segment. A total of 62 consecutive patients suffering L5/S1 lumbar disc herniation (LDH) with concomitant disc space narrowing or low-grade instability up to 5 mm translational slip in L5/S1 level were treated with lumbar interbody fusion (LIF) via posterior approach. Thirty-four of these patients (Coflex group) received an additional implantation of the interspinous spacer device (Coflex™) in the level L4/L5, while the rest of 28 patients (fusion group) underwent the fusion surgery alone. Clinical and radiographic examinations were performed at pre- and postoperative visits to compare the clinical outcomes and the changes of the L4/L5 vertebral disc degeneration on MRI in both Coflex and fusion group. Although both Coflex and fusion group showed improvements of the clinical outcomes assessed by the Oswestry Disability Index (ODI) after surgery, patients in Coflex group had more significant amelioration (P degeneration changes in Coflex group assessed by the relative signal intensity (RSI) differed from those in fusion group (P degeneration of the adjacent segment.

  16. Thin Shell, High Velocity Inertial Confinement Fusion Implosions on the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hurricane, O. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Callahan, D. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barrios, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Casey, D. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dewald, E. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dittrich, T. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Doppner, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Haan, S. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hinkel, D. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Berzak Hopkins, L. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Le Pape, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); MacPhee, A. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pak, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Park, H. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Patel, P. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Remington, B. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Robey, H. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Salmonson, J. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Springer, P. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tommasini, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Benedetti, L. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bionta, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bond, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bradley, D. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Caggiano, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Celliers, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cerjan, C. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Church, J. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dixit, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dylla-Spears, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Edgell, D. [Univ. of Rochester, NY (United States); Edwards, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Field, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fittinghoff, D. N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Frenje, J. A. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Gatu Johnson, M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Grim, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Guler, N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hatarik, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Herrmann, H. W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hsing, W. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Izumi, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jones, O. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Khan, S. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kilkenny, J. D. [General Atomics, San Diego, CA (United States); Knauer, J. [Univ. of Rochester, NY (United States); Kohut, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kozioziemski, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kritcher, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kyrala, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Landen, O. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); MacGowan, B. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mackinnon, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Meezan, N. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Merrill, F. E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Moody, J. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nagel, S. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nikroo, A. [General Atomics, San Diego, CA (United States); Parham, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ralph, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rosen, M. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rygg, J. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sater, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sayre, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Schneider, M. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shaughnessy, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Spears, B. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Town, R.P. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Volegov, P. L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wan, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Widmann, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wilde, C. H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Yeamans, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-04-06

    Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 μm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Earlier results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.

  17. Progress in theory and simulation of ion cyclotron emission from magnetic confinement fusion plasmas

    Science.gov (United States)

    Dendy, Richard; Chapman, Ben; Chapman, Sandra; Cook, James; Reman, Bernard; McClements, Ken; Carbajal, Leopoldo

    2016-10-01

    Suprathermal ion cyclotron emission (ICE) is detected from all large tokamak and stellarator plasmas. Its frequency spectrum has narrow peaks at sequential cyclotron harmonics of the energetic ion population (fusion-born or neutral beam-injected) at the outer edge of the plasma. ICE was the first collective radiative instability driven by confined fusion-born ions observed in deuterium-tritium plasmas in JET and TFTR, and the magnetoacoustic cyclotron instability is the most likely emission mechanism. Contemporary ICE measurements are taken at very high sampling rates from the LHD stellarator and from the conventional aspect ratio KSTAR tokamak. A correspondingly advanced modelling capability for the ICE emission mechanism has been developed using 1D3V PIC and hybrid-PIC codes, supplemented by analytical theory. These kinetic codes simulate the self-consistent full orbit dynamics of energetic and thermal ions, together with the electric and magnetic fields and the electrons. We report recent progress in theory and simulation that addresses: the scaling of ICE intensity with energetic particle density; the transition between super-Alfvénic and sub-Alfvénic regimes for the collectively radiating particles; and the rapid time evolution that is seen for some ICE measurements. This work was supported in part by the RCUK Energy Programme [Grant Number EP/I501045] and by Euratom.

  18. Noise temperature improvement for magnetic fusion plasma millimeter wave imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Lai, J.; Domier, C. W.; Luhmann, N. C. [Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616 (United States)

    2014-03-15

    Significant progress has been made in the imaging and visualization of magnetohydrodynamic and microturbulence phenomena in magnetic fusion plasmas [B. Tobias et al., Plasma Fusion Res. 6, 2106042 (2011)]. Of particular importance have been microwave electron cyclotron emission imaging and microwave imaging reflectometry systems for imaging T{sub e} and n{sub e} fluctuations. These instruments have employed heterodyne receiver arrays with Schottky diode mixer elements directly connected to individual antennas. Consequently, the noise temperature has been strongly determined by the conversion loss with typical noise temperatures of ∼60 000 K. However, this can be significantly improved by making use of recent advances in Monolithic Microwave Integrated Circuit chip low noise amplifiers to insert a pre-amplifier in front of the Schottky diode mixer element. In a proof-of-principle design at V-Band (50–75 GHz), significant improvement of noise temperature from the current 60 000 K to measured 4000 K has been obtained.

  19. Proceedings of the third symposium on the physics and technology of compact toroids in the magnetic fusion energy program

    Energy Technology Data Exchange (ETDEWEB)

    Siemon, R.E. (comp.)

    1981-03-01

    This document contains papers contributed by the participants of the Third Symposium on Physics and Technology of Compact Toroids in the Magnetic Fusion Energy Program. Subjects include reactor aspects of compact toroids, energetic particle rings, spheromak configurations (a mixture of toroidal and poloidal fields), and field-reversed configurations (FRC's that contain purely poloidal field).

  20. Multicharged ion-induced emission from metal- and insulator surfaces related to magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Winter, H.P. [Technische Univ., Vienna (Austria). Inst. fuer Allgemeine Physik

    1997-01-01

    The edge region of magnetically confined plasmas in thermonuclear fusion experiments couples the hot plasma core with the cold first wall. We consider the dependence of plasma-wall interaction processes on edge plasma properties, with particular emphasis on the role of slow multicharged ions (MCI). After a short survey on the physics of slow MCI-surface interaction we discuss recent extensive studies on MCI-induced electron emission from clean metal surfaces conducted at impact velocities << 1 a.u., from which generally reliable total electron yields can be obtained. We then demonstrate the essentially different role of the MCI charge for electron emission from metallic and insulator surfaces, respectively. Furthermore, we present recent results on slow MCI-induced `potential sputtering` of insulators which, in contrast to the well established kinetic sputtering, already occurs at very low ion impact energy and strongly increases with the MCI charge state. (J.P.N.). 55 refs.

  1. Damage production and accumulation in SiC structures in inertial and magnetic fusion systems

    Science.gov (United States)

    Sawan, M. E.; Ghoniem, N. M.; Snead, L.; Katoh, Y.

    2011-10-01

    Radiation damage parameters in SiC/SiC composite structures are determined in both magnetic (MFE) and inertial (IFE) confinement fusion systems. Variations in the geometry, neutron energy spectrum, and pulsed nature of neutron production result in significant differences in damage parameters between the two systems. With the same neutron wall loading, the displacement damage rate in the first wall in an IFE system is ˜10% lower than in an MFE system, while gas production and burnup rates are a factor of 2 lower. Self-cooled LiPb and Flibe blankets were analyzed. While using LiPb results in higher displacement damage, Flibe yields higher gas production and burnup rates. The effects of displacement damage and helium production on defect accumulation in SiC/SiC composites are also discussed.

  2. Geodesic least squares regression for scaling studies in magnetic confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Verdoolaege, Geert [Department of Applied Physics, Ghent University, Ghent, Belgium and Laboratory for Plasma Physics, Royal Military Academy, Brussels (Belgium)

    2015-01-13

    In regression analyses for deriving scaling laws that occur in various scientific disciplines, usually standard regression methods have been applied, of which ordinary least squares (OLS) is the most popular. However, concerns have been raised with respect to several assumptions underlying OLS in its application to scaling laws. We here discuss a new regression method that is robust in the presence of significant uncertainty on both the data and the regression model. The method, which we call geodesic least squares regression (GLS), is based on minimization of the Rao geodesic distance on a probabilistic manifold. We demonstrate the superiority of the method using synthetic data and we present an application to the scaling law for the power threshold for the transition to the high confinement regime in magnetic confinement fusion devices.

  3. Reaching High-Yield Fusion with a Slow Plasma Liner Compressing a Magnetized Target

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D D; Parks, P B

    2008-03-18

    Dynamics of the compression of a magnetized plasma target by a heavy liner made of partially ionized high high-Z material is discussed. A 'soft-landing' (shockless) mode of the liner deceleration is analyzed. Conclusion is drawn that such mode is possible for the liners whose thickness at the time of the first contact with the target is smaller than, roughly, 10% of the initial (un-compressed) target radius. A combination of the plasma liner with one or two glide cones allows for a direct access to the area near the center of the reactor chamber. One can then generate plasma target inside the plasma liner at the optimum time. The other advantage of the glide cones is that they can be used to deliver additional fuel to the center of the target near the point of a maximum compression and thereby increase the fusion yield.

  4. Efficacy of Combined Magnetic Field Treatment on Spinal Fusion: A Review of the Literature.

    Science.gov (United States)

    Phillips, Mark; Drew, Brian; Sprague, Sheila; Aleem, Ilyas

    2016-01-01

    Vertebral fractures place significant burdens on patients, caregivers, and the healthcare system at large. Nonunion is a frequent complication following vertebral fracture treatment, often resulting in significant patient pain and morbidity. Bone growth stimulators are an adjunct treatment modality proposed to increase rates of fracture healing. Combined magnetic field (CMF) bone growth stimulators have specifically been shown to increase union rates in patients with vertebral fractures. Certain populations, such as the elderly, postmenopausal women, and smokers, have demonstrated a preferentially greater response to CMF treatment. The present review focuses on the mechanism of action, efficacy, cost effectiveness, indications, contraindications, and safety of CMF treatment as an adjunct treatment for vertebral fractures. Future large high-quality investigations of adjunct CMF treatment for spine fusion patients focusing on patient-important outcomes are warranted.

  5. National High Magnetic Field Laboratory (NHMFL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Pulsed Field Program is located in Northern New Mexico at Los Alamos National Laboratory. The user program is designed to provide researchers with a balance of...

  6. National High Magnetic Field Laboratory (NHMFL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Pulsed Field Program is located in Northern New Mexico at Los Alamos National Laboratory. The user program is designed to provide researchers with a balance of...

  7. Hand Pose Estimation by Fusion of Inertial and Magnetic Sensing Aided by a Permanent Magnet.

    Science.gov (United States)

    Kortier, Henk G; Antonsson, Jacob; Schepers, H Martin; Gustafsson, Fredrik; Veltink, Peter H

    2015-09-01

    Tracking human body motions using inertial sensors has become a well-accepted method in ambulatory applications since the subject is not confined to a lab-bounded volume. However, a major drawback is the inability to estimate relative body positions over time because inertial sensor information only allows position tracking through strapdown integration, but does not provide any information about relative positions. In addition, strapdown integration inherently results in drift of the estimated position over time. We propose a novel method in which a permanent magnet combined with 3-D magnetometers and 3-D inertial sensors are used to estimate the global trunk orientation and relative pose of the hand with respect to the trunk. An Extended Kalman Filter is presented to fuse estimates obtained from inertial sensors with magnetic updates such that the position and orientation between the human hand and trunk as well as the global trunk orientation can be estimated robustly. This has been demonstrated in multiple experiments in which various hand tasks were performed. The most complex task in which simultaneous movements of both trunk and hand were performed resulted in an average rms position difference with an optical reference system of 19.7±2.2 mm whereas the relative trunk-hand and global trunk orientation error was 2.3±0.9 and 8.6±8.7 deg respectively.

  8. Estimating Orientation Using Magnetic and Inertial Sensors and Different Sensor Fusion Approaches: Accuracy Assessment in Manual and Locomotion Tasks

    Directory of Open Access Journals (Sweden)

    Elena Bergamini

    2014-10-01

    Full Text Available Magnetic and inertial measurement units are an emerging technology to obtain 3D orientation of body segments in human movement analysis. In this respect, sensor fusion is used to limit the drift errors resulting from the gyroscope data integration by exploiting accelerometer and magnetic aiding sensors. The present study aims at investigating the effectiveness of sensor fusion methods under different experimental conditions. Manual and locomotion tasks, differing in time duration, measurement volume, presence/absence of static phases, and out-of-plane movements, were performed by six subjects, and recorded by one unit located on the forearm or the lower trunk, respectively. Two sensor fusion methods, representative of the stochastic (Extended Kalman Filter and complementary (Non-linear observer filtering, were selected, and their accuracy was assessed in terms of attitude (pitch and roll angles and heading (yaw angle errors using stereophotogrammetric data as a reference. The sensor fusion approaches provided significantly more accurate results than gyroscope data integration. Accuracy improved mostly for heading and when the movement exhibited stationary phases, evenly distributed 3D rotations, it occurred in a small volume, and its duration was greater than approximately 20 s. These results were independent from the specific sensor fusion method used. Practice guidelines for improving the outcome accuracy are provided.

  9. Inference of total DT fusion neutron yield from prompt gamma-ray measurements at the National Ignition Facility

    Science.gov (United States)

    Church, J. A.; Herrmann, H. W.; Stoeffl, W.; Caggiano, J. A.; Cerjan, C.; Sayre, D.

    2014-10-01

    Prompt D-T fusion gamma-rays measured at the National Ignition Facility (NIF) with the Gamma-ray Reaction History detector (GRH) have been used recently to infer the total DT fusion neutron yield of inertial confinement fusion (ICF) implosions. DT fusion produces energetic gamma-rays (16.75 MeV) with a small branching ratio of approximately (4.2 +/- 2.0)e-5 γ/n. While the large error bar precludes use of the branching ratio for an accurate yield determination, the gamma-rays themselves provide the most unperturbed measure of fusion burn and can be used for such a purpose. A cross-calibration for the DT fusion gamma-ray to neutron signal is obtained via low areal density exploding pusher implosions which have mostly unperturbed neutron and gamma-ray signals. The calibration is then used to infer total DT neutron yield from gamma-ray measurements on high areal-density, cryogenically layered implosions in which neutrons are heavily down-scattered (up to 30%). Furthermore, the difference between the gamma-ray inferred total DT yield and the primary neutron yield (unscattered neutrons) can be used to estimate the total down-scatter fraction. Error analysis and comparison of yield values will be presented. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, LLNL-ABS-657694.

  10. The Status of Research Regarding Magnetic Mirrors as a Fusion Neutron Source or Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Simonen, T

    2008-12-23

    experiments have confirmed the physics of effluent plasma stabilization predicted by theory. The plasma had a mean ion energy of 10 keV and a density of 5e19m-3. If successful, the axisymmetric tandem mirror extension of the GDT idea could lead to a Q {approx} 10 power plant of modest size and would yield important applications at lower Q. In addition to the GDT method, there are four other ways to augment stability that have been demonstrated; including: plasma rotation (MCX), diverter coils (Tara), pondermotive (Phaedrus & Tara), and end wall funnel shape (Nizhni Novgorod). There are also 5 stabilization techniques predicted, but not yet demonstrated: expander kinetic pressure (KSTM-Post), Pulsed ECH Dynamic Stabilization (Post), wall stabilization (Berk), non-paraxial end mirrors (Ryutov), and cusp ends (Kesner). While these options should be examined further together with conceptual engineering designs. Physics issues that need further analysis include: electron confinement, MHD and trapped particle modes, analysis of micro stability, radial transport, evaluation and optimization of Q, and the plasma density needed to bridge to the expansion-region. While promising all should be examined through increased theory effort, university-scale experiments, and through increased international collaboration with the substantial facilities in Russia and Japan The conventional wisdom of magnetic mirrors was that they would never work as a fusion concept for a number of reasons. This conventional wisdom is most probably all wrong or not applicable, especially for applications such as low Q (DT Neutron Source) aimed at materials testing or for a Q {approx} 3-5 fusion neutron source applied to destroying actinides in fission waste and breeding of fissile fuel.

  11. Classification of brain disease in magnetic resonance images using two-stage local feature fusion

    Science.gov (United States)

    Li, Tao; Li, Wu; Yang, Yehui

    2017-01-01

    Background Many classification methods have been proposed based on magnetic resonance images. Most methods rely on measures such as volume, the cerebral cortical thickness and grey matter density. These measures are susceptible to the performance of registration and limited in representation of anatomical structure. This paper proposes a two-stage local feature fusion method, in which deformable registration is not desired and anatomical information is represented from moderate scale. Methods Keypoints are firstly extracted from scale-space to represent anatomical structure. Then, two kinds of local features are calculated around the keypoints, one for correspondence and the other for representation. Scores are assigned for keypoints to quantify their effect in classification. The sum of scores for all effective keypoints is used to determine which group the test subject belongs to. Results We apply this method to magnetic resonance images of Alzheimer's disease and Parkinson's disease. The advantage of local feature in correspondence and representation contributes to the final classification. With the help of local feature (Scale Invariant Feature Transform, SIFT) in correspondence, the performance becomes better. Local feature (Histogram of Oriented Gradient, HOG) extracted from 16×16 cell block obtains better results compared with 4×4 and 8×8 cell block. Discussion This paper presents a method which combines the effect of SIFT descriptor in correspondence and the representation ability of HOG descriptor in anatomical structure. This method has the potential in distinguishing patients with brain disease from controls. PMID:28207873

  12. Plasma expansion across a transverse magnetic field in a negative hydrogen ion source for fusion

    Science.gov (United States)

    Fantz, U.; Schiesko, L.; Wünderlich, D.

    2014-08-01

    High power negative hydrogen ion sources operating at 0.3 Pa are a key component of the neutral beam injection systems for the international fusion experiment ITER. To achieve the required large ion current at a tolerable number of co-extracted electrons the source is equipped with a magnetic filter field (up to 10 mT). The IPP prototype source (1/8 of the area of the ITER source) has been equipped with a flexible magnetic filter frame to perform filter field studies (position, polarity, strength). Axial profiles of the plasma parameters are measured with two Langmuir probes, positioned in the upper and the lower half of the expansion chamber. In addition to the expected decrease in electron temperature and density a vertical drift develops the direction depending on the polarity of the field. Without field no drift is observed. The drift is less pronounced in caesium seeded discharges and almost vanishes in deuterium, indicating an influence of the ion mass on the drift. A comparison with results from a half-size ITER source reveals that the plasma is much more uniform in the large source.

  13. New option for solving the climatic problems with non-thermal laser driven boron fusion and ultrahigh magnetic fields

    CERN Document Server

    Hora, Heinrich

    2014-01-01

    In contrast to the broad stream of sustainable developments on fusion energy, new aspects are developed now by applying ultra-short, ultra-powerful laser pulses in a plasma-block ignition scheme by avoiding the well known difficulties of thermal-pressure instabilities and losses through using electro-dynamic non-thermal energy conversion. A further advantage is given by the new 10 kilo-Tesla magnetic fields for fusion of uncompressed proton-boron fuel which avoids problems of dangerous nuclear radiation.

  14. The interaction of the near-field plasma with antennas used in magnetic fusion research

    Science.gov (United States)

    Caughman, John

    2015-09-01

    Plasma heating and current drive using antennas in the Ion Cyclotron Range of Frequencies (ICRF) are important elements for the success of magnetic fusion. The antennas must operate in a harsh environment, where local plasma densities can be >1018/m3, magnetic fields can range from 0.2-5 Tesla, and antenna operating voltages can be >40 kV. This environment creates operational issues due to the interaction of the near-field of the antenna with the local plasma. In addition to parasitic losses in this plasma region, voltage and current distributions on the antenna structure lead to the formation of high electric fields and RF plasma sheaths, which can lead to enhanced particle and energy fluxes on the antenna and on surfaces intersected by magnetic field lines connected to or passing near the antenna. These issues are being studied using a simple electrode structure and a single-strap antenna on the Prototype Materials Plasma EXperiment (Proto-MPEX) at ORNL, which is a linear plasma device that uses an electron Bernstein wave heated helicon plasma source to create a high-density plasma suitable for use in a plasma-material interaction test stand. Several diagnostics are being used to characterize the near-field interactions, including double-Langmuir probes, a retarding field energy analyzer, and optical emission spectroscopy. The RF electric field is being studied utilizing Dynamic Stark Effect spectroscopy and Doppler-Free Saturation Spectroscopy. Recent experimental results and future plans will be presented. ORNL is managed by UT-Battelle, LLC, for the U.S. DOE under Contract DE-AC-05-00OR22725.

  15. Scaling mechanisms of vapour/plasma shielding from laser-produced plasmas to magnetic fusion regimes

    Science.gov (United States)

    Sizyuk, Tatyana; Hassanein, Ahmed

    2014-02-01

    The plasma shielding effect is a well-known mechanism in laser-produced plasmas (LPPs) reducing laser photon transmission to the target and, as a result, significantly reducing target heating and erosion. The shielding effect is less pronounced at low laser intensities, when low evaporation rate together with vapour/plasma expansion processes prevent establishment of a dense plasma layer above the surface. Plasma shielding also loses its effectiveness at high laser intensities when the formed hot dense plasma plume causes extensive target erosion due to radiation fluxes back to the surface. The magnitude of emitted radiation fluxes from such a plasma is similar to or slightly higher than the laser photon flux in the low shielding regime. Thus, shielding efficiency in LPPs has a peak that depends on the laser beam parameters and the target material. A similar tendency is also expected in other plasma-operating devices such as tokamaks of magnetic fusion energy (MFE) reactors during transient plasma operation and disruptions on chamber walls when deposition of the high-energy transient plasma can cause severe erosion and damage to the plasma-facing and nearby components. A detailed analysis of these abnormal events and their consequences in future power reactors is limited in current tokamak reactors. Predictions for high-power future tokamaks are possible only through comprehensive, time-consuming and rigorous modelling. We developed scaling mechanisms, based on modelling of LPP devices with their typical temporal and spatial scales, to simulate tokamak abnormal operating regimes to study wall erosion, plasma shielding and radiation under MFE reactor conditions. We found an analogy in regimes and results of carbon and tungsten erosion of the divertor surface in ITER-like reactors with erosion due to laser irradiation. Such an approach will allow utilizing validated modelling combined with well-designed and well-diagnosed LPP experimental studies for predicting

  16. Enhanced Computational Infrastructure for Data Analysis at the DIII-D National Fusion Facility

    Energy Technology Data Exchange (ETDEWEB)

    Schissel, D.P.; Peng, Q.; Schachter, J.; Terpstra, T.B.; Casper, T.A.; Freeman, J.; Jong, R.; Keith, K.M.; Meyer, W.H.; Parker, C.T.

    1999-08-01

    Recently a number of enhancements to the computer hardware infrastructure have been implemented at the DIII-D National Fusion Facility. Utilizing these improvements to the hardware infrastructure, software enhancements are focusing on streamlined analysis, automation, and graphical user interface (GUI) systems to enlarge the user base. The adoption of the load balancing software package LSF Suite by Platform Computing has dramatically increased the availability of CPU cycles and the efficiency of their use. Streamlined analysis has been aided by the adoption of the MDSplus system to provide a unified interface to analyzed DIII-D data. The majority of MDSplus data is made available in between pulses giving the researcher critical information before setting up the next pulse. Work on data viewing and analysis tools focuses on efficient GUI design with object-oriented programming (OOP) for maximum code flexibility. Work to enhance the computational infrastructure at DIII-D has included a significant effort to aid the remote collaborator since the DIII-D National Team consists of scientists from 9 national laboratories, 19 foreign laboratories, 16 universities, and 5 industrial partnerships. As a result of this work, DIII-D data is available on a 24 x 7 basis from a set of viewing and analysis tools that can be run either on the collaborators' or DIII-Ds computer systems. Additionally, a Web based data and code documentation system has been created to aid the novice and expert user alike.

  17. Fully automated prostate magnetic resonance imaging and transrectal ultrasound fusion via a probabilistic registration metric

    Science.gov (United States)

    Sparks, Rachel; Bloch, B. Nicholas; Feleppa, Ernest; Barratt, Dean; Madabhushi, Anant

    2013-03-01

    In this work, we present a novel, automated, registration method to fuse magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) images of the prostate. Our methodology consists of: (1) delineating the prostate on MRI, (2) building a probabilistic model of prostate location on TRUS, and (3) aligning the MRI prostate segmentation to the TRUS probabilistic model. TRUS-guided needle biopsy is the current gold standard for prostate cancer (CaP) diagnosis. Up to 40% of CaP lesions appear isoechoic on TRUS, hence TRUS-guided biopsy cannot reliably target CaP lesions and is associated with a high false negative rate. MRI is better able to distinguish CaP from benign prostatic tissue, but requires special equipment and training. MRI-TRUS fusion, whereby MRI is acquired pre-operatively and aligned to TRUS during the biopsy procedure, allows for information from both modalities to be used to help guide the biopsy. The use of MRI and TRUS in combination to guide biopsy at least doubles the yield of positive biopsies. Previous work on MRI-TRUS fusion has involved aligning manually determined fiducials or prostate surfaces to achieve image registration. The accuracy of these methods is dependent on the reader's ability to determine fiducials or prostate surfaces with minimal error, which is a difficult and time-consuming task. Our novel, fully automated MRI-TRUS fusion method represents a significant advance over the current state-of-the-art because it does not require manual intervention after TRUS acquisition. All necessary preprocessing steps (i.e. delineation of the prostate on MRI) can be performed offline prior to the biopsy procedure. We evaluated our method on seven patient studies, with B-mode TRUS and a 1.5 T surface coil MRI. Our method has a root mean square error (RMSE) for expertly selected fiducials (consisting of the urethra, calcifications, and the centroids of CaP nodules) of 3.39 +/- 0.85 mm.

  18. Reactor for boron fusion with picosecond ultrahigh power laser pulses and ultrahigh magnetic field trapping

    CERN Document Server

    Miley, G H; Kirchhoff, G

    2015-01-01

    Compared with the deuterium tritium (DT) fusion, the environmentally clean fusion of protons with 11B is extremely difficult. When instead of nanosecond laser pulses for thermal-ablating driven ignition, picosecond pulses are used, a drastic change by nonlinearity results in ultrahigh acceleration of plasma blocks. This radically changes to economic boron fusion by a measured new avalanche ignition.

  19. Tissue identification with micro-magnetic resonance imaging in a caprine spinal fusion model

    NARCIS (Netherlands)

    M.P. Uffen; M.R. Krijnen; R.J. Hoogendoorn; G.J. Strijkers; V. Everts; P.I. Wuisman; T.H. Smit

    2008-01-01

    Nonunion is a major complication of spinal interbody fusion. Currently X-ray and computed tomography (CT) are used for evaluating the spinal fusion process. However, both imaging modalities have limitations in judgment of the early stages of this fusion process, as they only visualize mineralized bo

  20. Fusion Materials Research at Oak Ridge National Laboratory in Fiscal Year 2014

    Energy Technology Data Exchange (ETDEWEB)

    Wiffen, Frederick W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Noe, Susan P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Snead, Lance Lewis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-10-01

    The realization of fusion energy is a formidable challenge with significant achievements resulting from close integration of the plasma physics and applied technology disciplines. Presently, the most significant technological challenge for the near-term experiments such as ITER, and next generation fusion power systems, is the inability of current materials and components to withstand the harsh fusion nuclear environment. The overarching goal of the ORNL fusion materials program is to provide the applied materials science support and understanding to underpin the ongoing DOE Office of Science fusion energy program while developing materials for fusion power systems. In doing so the program continues to be integrated both with the larger U.S. and international fusion materials communities, and with the international fusion design and technology communities.

  1. Ignition and Thermonuclear Burn on the National Ignition Facility with Imposed Magnetic Fields

    Science.gov (United States)

    Perkins, L. John; Logan, B. G.; Rhodes, M. A.; Zimmerman, G. B.; Ho, D. D.; Blackfield, D. T.; Hawkins, S. A.

    2016-10-01

    We are studying the impact of highly compressed magnetic fields on enhancing the prospects for ignition and burn on the National Ignition Facility (NIF). Both magnetized room-temperature DT gas targets and cryo-ignition capsules are under study. Applied seed fields of 20-70T that compress to greater than 10000T (100MG) under implosion can reduce hotspot conditions required for ignition and propagating burn through range reduction and magnetic mirror trapping of fusion alpha particles, suppression of electron heat conduction and potential stabilization of hydrodynamic instabilities. The applied field may also reduce hohlraum laser-plasma instabilities and suppress the transport of hot electron preheat to the capsule. These combined B-field attributes may permit recovery of ignition, or at least significant alpha particle heating, in capsules that are otherwise submarginal through adverse hydrodynamic or hohlraum-drive conditions. Simulations indicate that optimum initial fields of 50T may produce multi-MJ-yields when applied to our present best experimental capsules. Proof-of-principle experiments for magnetized ignition capsules and hohlraum physics on NIF are now being designed. This work performed under auspices of U.S. DOE by LLNL under Contract DE-AC52-07NA27344.

  2. Scaling magnetized liner inertial fusion on Z and future pulsed-power accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Slutz, S. A.; Stygar, W. A.; Gomez, M. R.; Peterson, K. J.; Sefkow, A. B.; Sinars, D. B.; Vesey, R. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Campbell, E. M.; Betti, R. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 146 (United States)

    2016-02-15

    The MagLIF (Magnetized Liner Inertial Fusion) concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] has demonstrated fusion–relevant plasma conditions [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z accelerator with a peak drive current of about 18 MA. We present 2D numerical simulations of the scaling of MagLIF on Z as a function of drive current, preheat energy, and applied magnetic field. The results indicate that deuterium-tritium (DT) fusion yields greater than 100 kJ could be possible on Z when all of these parameters are at the optimum values: i.e., peak current = 25 MA, deposited preheat energy = 5 kJ, and B{sub z} = 30 T. Much higher yields have been predicted [S. A. Slutz and R. A. Vesey, Phys. Rev. Lett. 108, 025003 (2012)] for MagLIF driven with larger peak currents. Two high performance pulsed-power accelerators (Z300 and Z800) based on linear-transformer-driver technology have been designed [W. A. Stygar et al., Phys. Rev. ST Accel. Beams 18, 110401 (2015)]. The Z300 design would provide 48 MA to a MagLIF load, while Z800 would provide 65 MA. Parameterized Thevenin-equivalent circuits were used to drive a series of 1D and 2D numerical MagLIF simulations with currents ranging from what Z can deliver now to what could be achieved by these conceptual future pulsed-power accelerators. 2D simulations of simple MagLIF targets containing just gaseous DT have yields of 18 MJ for Z300 and 440 MJ for Z800. The 2D simulated yield for Z800 is increased to 7 GJ by adding a layer of frozen DT ice to the inside of the liner.

  3. LLE 1998 annual report, October 1997--September 1998. Inertial fusion program and National Laser Users` Facility program

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    This report summarizes research at the Laboratory for Laser Energetics (LLE), the operation of the National Laser Users` Facility (NLUF), and programs involving the education of high school, undergraduate, and graduate students for FY98. Research summaries cover: progress in laser fusion; diagnostic development; laser and optical technology; and advanced technology for laser targets.

  4. The Effects of Weak Combined Magnetic Field on Cell Wall Regeneration and Frequency of Plant Protoplasts Fusion

    Science.gov (United States)

    Nedukha, Olena

    The major purpose of these experiments was to investigate plant protoplast fusion frequency and regeneration of a cell wall by protoplasts at weak combined magnetic field (CMF) with the frequency resonance to the cyclotron frequency of Mg2+, Ca2+ and K+ ions. The protoplasts were isolated from Nicotiana lumbaginifolia and N. silvestris leaf mesophyll and from callus tissues (Nicotiana tabacum and Glycine max). The special extra apparatus with ferromagnetic shield was used for estimate of CMF with the frequency resonance to the cyclotron frequency of Mg2+, Ca2+ and K+ ions. The fusion of protoplasts is realized by using of parent protoplasts isolated from one plant species, as well as from various plant species. Control samples were situated near the apparatus with CMF. The laser confocal microscopy was used for study of cell wall regeneration by single and fused protoplasts. The cytochemical methods with DAPI and calcofluor dye were also applied as the detectors for protoplast fusion and regeneration of cell wall. We have been established that CMF with frequency adjusted to the cyclotron frequency Mg2+ ions have shown the most positive influence on regeneration of cell wall by protoplasts. CMF adjusted to the cyclotron frequency of K+ ions very weakly affected on the frequency of protoplast fusion. Largest frequency of protoplasts fusion is noted in the CMF adjusted to the cyclotron frequency of Ca2+ in comparison with the control samples.

  5. Seeking tools for image fusion between computed tomography, structural and functional magnetic resonance methods for applications in neurosurgery

    Directory of Open Access Journals (Sweden)

    Liana Guerra Sanches da Rocha

    2012-06-01

    Full Text Available Objective: To evaluate tools for the fusion of images generatedby tomography and structural and functional magnetic resonanceimaging. Methods: Magnetic resonance and functional magneticresonance imaging were performed while a volunteer who hadpreviously undergone cranial tomography performed motor andsomatosensory tasks in a 3-Tesla scanner. Image data were analyzedwith different programs, and the results were compared. Results:We constructed a flow chart of computational processes that allowedmeasurement of the spatial congruence between the methods. Therewas no single computational tool that contained the entire set offunctions necessary to achieve the goal. Conclusion: The fusion ofthe images from the three methods proved to be feasible with the useof four free-access software programs (OsiriX, Register, MRIcro andFSL. Our results may serve as a basis for building software that willbe useful as a virtual tool prior to neurosurgery.

  6. Spectroscopic Studies of Atomic and Molecular Processes in the Edge Region of Magnetically Confined Fusion Plasmas

    Science.gov (United States)

    Hey, J. D.; Brezinsek, S.; Mertens, Ph.; Unterberg, B.

    2006-12-01

    Edge plasma studies are of vital importance for understanding plasma-wall interactions in magnetically confined fusion devices. These interactions determine the transport of neutrals into the plasma, and the properties of the plasma discharge. This presentation deals with optical spectroscopic studies of the plasma boundary, and their rôle in elucidating the prevailing physical conditions. Recorded spectra are of four types: emission spectra of ions and atoms, produced by electron impact excitation and by charge-exchange recombination, atomic spectra arising from electron impact-induced molecular dissociation and ionisation, visible spectra of molecular hydrogen and its isotopic combinations, and laser-induced fluorescence (LIF) spectra. The atomic spectra are strongly influenced by the confining magnetic field (Zeeman and Paschen-Back effects), which produces characteristic features useful for species identification, temperature determination by Doppler broadening, and studies of chemical and physical sputtering. Detailed analysis of the Zeeman components in both optical and LIF spectra shows that atomic hydrogen is produced in various velocity classes, some related to the relevant molecular Franck-Condon energies. The latter reflect the dominant electron collision processes responsible for production of atoms from molecules. This assignment has been verified by gas-puffing experiments through special test limiters. The higher-energy flanks of hydrogen line profiles probably also show the influence of charge-exchange reactions with molecular ions accelerated in the plasma sheath (`scrape-off layer') separating limiter surfaces from the edge plasma, in analogy to acceleration in the cathode-fall region of gas discharges. While electron collisions play a vital rôle in generating the spectra, ion collisions with excited atomic radiators act through re-distribution of population among the atomic fine-structure sublevels, and momentum transfer to the atomic nuclei

  7. Damage of actively cooled plasma facing components of magnetic confinement controlled fusion machines

    Energy Technology Data Exchange (ETDEWEB)

    Chevet, G. [Association Euratom-CEA, DSM/DRFC, CEA Cadarache, Saint-Paul-Lez-Durance (France)], E-mail: gaelle.chevet@cea.fr; Schlosser, J. [Association Euratom-CEA, DSM/DRFC, CEA Cadarache, Saint-Paul-Lez-Durance (France); Martin, E.; Herb, V.; Camus, G. [Universite Bordeaux 1, UMR 5801 (CNRS-SAFRAN-CEA-UB1), Laboratoire des Composites Thermostructuraux, F-33600 Pessac (France)

    2009-03-31

    Plasma facing components (PFCs) of magnetic fusion machines have high manufactured residual stresses and have to withstand important stress ranges during operation. These actively cooled PFCs have a carbon fibre composite (CFC) armour and a copper alloy heat sink. Cracks mainly appear in the CFC near the composite/copper interface. In order to analyse damage mechanisms, it is important to well simulate the damage mechanisms both of the CFC and the CFC/Cu interface. This study focuses on the mechanical behaviour of the N11 material for which the scalar ONERA damage model was used. The damage parameters of this model were identified by similarity to a neighbour material, which was extensively analysed, according to the few characterization test results available for the N11. The finite elements calculations predict a high level of damage of the CFC at the interface zone explaining the encountered difficulties in the PFCs fabrication. These results suggest that the damage state of the CFC cells is correlated with a conductivity decrease to explain the temperature increase of the armour surface under fatigue heat load.

  8. Test of 60 kA coated conductor cable prototypes for fusion magnets

    Science.gov (United States)

    Uglietti, D.; Bykovsky, N.; Sedlak, K.; Stepanov, B.; Wesche, R.; Bruzzone, P.

    2015-12-01

    Coated conductors could be promising materials for the fabrication of the large magnet systems of future fusion devices. Two prototype conductors (flat cables in steel conduits), each about 2 m long, were manufactured using coated conductor tapes (4 mm wide) from Super Power and SuperOx, with a total tape length of 1.6 km. Each flat cable is assembled from 20 strands, each strand consisting of a stack of 16 tapes surrounded by two half circular copper profiles, twisted and soldered. The tapes were measured at 12 T and 4.2 K and the results of the measurements were used for the assessment of the conductor electromagnetic properties at low temperature and high field. The two conductors were assembled together in a sample that was tested in the European Dipole (EDIPO) facility. The current sharing temperatures of the two conductors were measured at background fields from 8 T up to 12 T and for currents from 30 kA up to 70 kA: the measured values are within a few percent of the values expected from the measurements on tapes (short samples). After electromagnetic cycling, T cs at 12 T and 50 kA decreased from about 12 K to 11 K (about 10%), corresponding to less than 3% of I c.

  9. Parallel mesh support for particle-in-cell methods in magnetic fusion simulations

    Science.gov (United States)

    Yoon, Eisung; Shephard, Mark S.; Seol, E. Seegyoung; Kalyanaraman, Kaushik; Ibanez, Daniel

    2016-10-01

    As supercomputing power continues to increase Particle-In-Cell (PIC) methods are being widely adopted for transport simulations of magnetic fusion devices. Current implementations place a copy of the entire continuum mesh and its fields used in the PIC calculations on every node. This is in general not a scalable solution as computational power continues to grow faster than node level memory. To address this scalability issue, while still maintaining sufficient mesh per node to control costly inter-node communication, a new unstructured mesh distribution methods and associated mesh based PIC calculation procedure is being developed building on the parallel unstructured mesh infrastructure (PUMI). Key components to be outlined in the presentation include (i) the mesh distribution strategy, (ii) how the particles are tracked during a push cycle taking advantage of the unstructured mesh adjacency structures and searches based on that structure, and (iii) how the field solve steps and particle migration are controlled. Performance comparisons to the current approach will also be presented.

  10. Damage of actively cooled plasma facing components of magnetic confinement controlled fusion machines

    Science.gov (United States)

    Chevet, G.; Schlosser, J.; Martin, E.; Herb, V.; Camus, G.

    2009-03-01

    Plasma facing components (PFCs) of magnetic fusion machines have high manufactured residual stresses and have to withstand important stress ranges during operation. These actively cooled PFCs have a carbon fibre composite (CFC) armour and a copper alloy heat sink. Cracks mainly appear in the CFC near the composite/copper interface. In order to analyse damage mechanisms, it is important to well simulate the damage mechanisms both of the CFC and the CFC/Cu interface. This study focuses on the mechanical behaviour of the N11 material for which the scalar ONERA damage model was used. The damage parameters of this model were identified by similarity to a neighbour material, which was extensively analysed, according to the few characterization test results available for the N11. The finite elements calculations predict a high level of damage of the CFC at the interface zone explaining the encountered difficulties in the PFCs fabrication. These results suggest that the damage state of the CFC cells is correlated with a conductivity decrease to explain the temperature increase of the armour surface under fatigue heat load.

  11. Laser propagation measurements in long-scale-length underdense plasmas relevant to magnetized liner inertial fusion

    Science.gov (United States)

    Harvey-Thompson, A. J.; Sefkow, A. B.; Wei, M. S.; Nagayama, T.; Campbell, E. M.; Blue, B. E.; Heeter, R. F.; Koning, J. M.; Peterson, K. J.; Schmitt, A.

    2016-11-01

    We report experimental results and simulations showing efficient laser energy coupling into plasmas at conditions relevant to the magnetized liner inertial fusion (MagLIF) concept. In MagLIF, to limit convergence and increase the hydrodynamic stability of the implosion, the fuel must be efficiently preheated. To determine the efficiency and physics of preheating by a laser, an Ar plasma with ne/nc r i t˜0.04 is irradiated by a multi-ns, multi-kJ, 0.35-μm, phase-plate-smoothed laser at spot-averaged intensities ranging from 1.0 ×1014 to 2.5 ×1014W /c m2 and pulse widths from 2 to 10 ns. Time-resolved x-ray images of the laser-heated plasma are compared to two-dimensional radiation-hydrodynamic simulations that show agreement with the propagating emission front, a comparison that constrains laser energy deposition to the plasma. The experiments show that long-pulse, modest-intensity (I =1.5 ×1014W /c m2 ) beams can efficiently couple energy (˜82 % of the incident energy) to MagLIF-relevant long-length (9.5 mm) underdense plasmas. The demonstrated heating efficiency is significantly higher than is thought to have been achieved in early integrated MagLIF experiments [A. B. Sefkow et al., Phys. Plasmas 21, 072711 (2014), 10.1063/1.4890298].

  12. Accuracy of postoperative computed tomography and magnetic resonance image fusion for assessing deep brain stimulation electrodes.

    Science.gov (United States)

    Thani, Nova B; Bala, Arul; Swann, Gary B; Lind, Christopher R P

    2011-07-01

    Knowledge of the anatomic location of the deep brain stimulation (DBS) electrode in the brain is essential in quality control and judicious selection of stimulation parameters. Postoperative computed tomography (CT) imaging coregistered with preoperative magnetic resonance imaging (MRI) is commonly used to document the electrode location safely. The accuracy of this method, however, depends on many factors, including the quality of the source images, the area of signal artifact created by the DBS lead, and the fusion algorithm. To calculate the accuracy of determining the location of active contacts of the DBS electrode by coregistering postoperative CT image to intraoperative MRI. Intraoperative MRI with a surrogate marker (carbothane stylette) was digitally coregistered with postoperative CT with DBS electrodes in 8 consecutive patients. The location of the active contact of the DBS electrode was calculated in the stereotactic frame space, and the discrepancy between the 2 images was assessed. The carbothane stylette significantly reduces the signal void on the MRI to a mean diameter of 1.4 ± 0.1 mm. The discrepancy between the CT and MRI coregistration in assessing the active contact location of the DBS lead is 1.6 ± 0.2 mm, P Medtronic, Minneapolis, Minnesota) software. CT/MRI coregistration is an acceptable method of identifying the anatomic location of DBS electrode and active contacts.

  13. The National Ignition Facility Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

    CERN Document Server

    Moses, E I

    2001-01-01

    The National Ignition Facility (NIF) currently under construction at the University of California Lawrence Livermore National Laboratory (LLNL) is a 192-beam, 1.8-megajoule, 500-terawatt, 351-nm laser for inertial confinement fusion (ICF) and high-energy-density experimental studies. NIF is being built by the Department of Energy and the National Nuclear Security Agency (NNSA) to provide an experimental test bed for the U.S. Stockpile Stewardship Program to ensure the country's nuclear deterrent without underground nuclear testing. The experimental program will encompass a wide range of physical phenomena from fusion energy production to materials science. Of the roughly 700 shots available per year, about 10% will be dedicated to basic science research. Laser hardware is modularized into line replaceable units (LRUs) such as deformable mirrors, amplifiers, and multi-function sensor packages that are operated by a distributed computer control system of nearly 60,000 control points. The supervisory control roo...

  14. The National Ignition Facility: The Path to Ignition, High Energy Density Science and Inertial Fusion Energy

    Energy Technology Data Exchange (ETDEWEB)

    Moses, E

    2011-03-25

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is a Nd:Glass laser facility capable of producing 1.8 MJ and 500 TW of ultraviolet light. This world's most energetic laser system is now operational with the goals of achieving thermonuclear burn in the laboratory and exploring the behavior of matter at extreme temperatures and energy densities. By concentrating the energy from its 192 extremely energetic laser beams into a mm{sup 3}-sized target, NIF can produce temperatures above 100 million K, densities of 1,000 g/cm{sup 3}, and pressures 100 billion times atmospheric pressure - conditions that have never been created in a laboratory and emulate those in the interiors of planetary and stellar environments. On September 29, 2010, NIF performed the first integrated ignition experiment which demonstrated the successful coordination of the laser, the cryogenic target system, the array of diagnostics and the infrastructure required for ignition. Many more experiments have been completed since. In light of this strong progress, the U.S. and the international communities are examining the implication of achieving ignition on NIF for inertial fusion energy (IFE). A laser-based IFE power plant will require a repetition rate of 10-20 Hz and a 10% electrical-optical efficiency laser, as well as further advances in large-scale target fabrication, target injection and tracking, and other supporting technologies. These capabilities could lead to a prototype IFE demonstration plant in 10- to 15-years. LLNL, in partnership with other institutions, is developing a Laser Inertial Fusion Energy (LIFE) baseline design and examining various technology choices for LIFE power plant This paper will describe the unprecedented experimental capabilities of the NIF, the results achieved so far on the path toward ignition, the start of fundamental science experiments and plans to transition NIF to an international user facility

  15. Multiattribute probabilistic prostate elastic registration (MAPPER): Application to fusion of ultrasound and magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sparks, Rachel, E-mail: rachel.sparks@ucl.ac.uk; Barratt, Dean [Centre for Medical Image Computing, University College London, London WC1E 6BT (United Kingdom); Nicolas Bloch, B. [Department of Radiology, Boston Medical Center and Boston University, Boston, Massachusetts 02118 (United States); Feleppa, Ernest [Lizzi Center for Biomedical Engineering, Riverside Research Institute, New York, New York 10038 (United States); Moses, Daniel [South Western Sydney Clinical School, University of New South Wales, Sydney NSW 2052 (Australia); Ponsky, Lee [Department of Urology, University Hospitals Case Medical Center, Cleveland, Ohio 44106 (United States); Madabhushi, Anant, E-mail: anantm@case.edu [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 (United States)

    2015-03-15

    Purpose: Transrectal ultrasound (TRUS)-guided needle biopsy is the current gold standard for prostate cancer diagnosis. However, up to 40% of prostate cancer lesions appears isoechoic on TRUS. Hence, TRUS-guided biopsy has a high false negative rate for prostate cancer diagnosis. Magnetic resonance imaging (MRI) is better able to distinguish prostate cancer from benign tissue. However, MRI-guided biopsy requires special equipment and training and a longer procedure time. MRI-TRUS fusion, where MRI is acquired preoperatively and then aligned to TRUS, allows for advantages of both modalities to be leveraged during biopsy. MRI-TRUS-guided biopsy increases the yield of cancer positive biopsies. In this work, the authors present multiattribute probabilistic postate elastic registration (MAPPER) to align prostate MRI and TRUS imagery. Methods: MAPPER involves (1) segmenting the prostate on MRI, (2) calculating a multiattribute probabilistic map of prostate location on TRUS, and (3) maximizing overlap between the prostate segmentation on MRI and the multiattribute probabilistic map on TRUS, thereby driving registration of MRI onto TRUS. MAPPER represents a significant advancement over the current state-of-the-art as it requires no user interaction during the biopsy procedure by leveraging texture and spatial information to determine the prostate location on TRUS. Although MAPPER requires manual interaction to segment the prostate on MRI, this step is performed prior to biopsy and will not substantially increase biopsy procedure time. Results: MAPPER was evaluated on 13 patient studies from two independent datasets—Dataset 1 has 6 studies acquired with a side-firing TRUS probe and a 1.5 T pelvic phased-array coil MRI; Dataset 2 has 7 studies acquired with a volumetric end-firing TRUS probe and a 3.0 T endorectal coil MRI. MAPPER has a root-mean-square error (RMSE) for expert selected fiducials of 3.36 ± 1.10 mm for Dataset 1 and 3.14 ± 0.75 mm for Dataset 2. State

  16. Suppressing electron turbulence and triggering internal transport barriers with reversed magnetic shear in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, J. L. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Bell, R.; Guttenfelder, W.; Hammett, G. W.; Kaye, S. M.; LeBlanc, B.; Mikkelsen, D. R. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Candy, J. [General Atomics, San Diego, California 92186 (United States); Smith, D. R. [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Yuh, H. Y. [Nova Photonics Inc., Princeton, New Jersey 08540 (United States)

    2012-05-15

    The National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 (2000)] can achieve high electron plasma confinement regimes that are super-critically unstable to the electron temperature gradient driven (ETG) instability. These plasmas, dubbed electron internal transport barriers (e-ITBs), occur when the magnetic shear becomes strongly negative. Using the gyrokinetic code GYRO [J. Candy and R. E. Waltz, J. Comput. Phys. 186, 545 (2003)], the first nonlinear ETG simulations of NSTX e-ITB plasmas reinforce this observation. Local simulations identify a strongly upshifted nonlinear critical gradient for thermal transport that depends on magnetic shear. Global simulations show e-ITB formation can occur when the magnetic shear becomes strongly negative. While the ETG-driven thermal flux at the outer edge of the barrier is large enough to be experimentally relevant, the turbulence cannot propagate past the barrier into the plasma interior.

  17. An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices

    Science.gov (United States)

    Hartwig, Zachary S.; Barnard, Harold S.; Lanza, Richard C.; Sorbom, Brandon N.; Stahle, Peter W.; Whyte, Dennis G.

    2013-12-01

    This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (˜1 m), high-current (˜1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields - in between plasma shots - to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ˜5 μm into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

  18. Interaction between sheared flows and turbulent transport in magnetized fusion-grade plasmas; Interaction entre ecoulements cisailles et transport turbulent dans les plasmas de fusion magnetique

    Energy Technology Data Exchange (ETDEWEB)

    Leconte, M.

    2008-11-15

    The H confinement regime is set when the heating power reaches a threshold value P{sub c} and is linked to the formation of a transport barrier in the edge region of the plasma. Such a barrier is characterized by a high pressure gradient and is submitted to ELM (edge localized mode) instabilities. ELM instabilities trigger violent quasi-periodical ejections of matter and heat that induce quasi-periodical relaxations of the transport barrier called relaxation oscillations. In this work we studied the interaction between sheared flows and turbulence in fusion plasmas. In particular, we studied the complex dynamics of a transport barrier and we show through a simulation that resonant magnetic perturbations could control relaxation oscillations without a significant loss of confinement

  19. The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

    Energy Technology Data Exchange (ETDEWEB)

    Moses, E I; Wuest, C R

    2002-10-16

    The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, 351-nm laser system and a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. NIF is being built by the National Nuclear Security Administration and when completed will be the world's largest laser experimental system, providing a national center to study inertial confinement fusion and the physics of matter at extreme energy densities and pressures. NIF will provide 192 energetic laser beams that will compress small fusion targets to conditions where they will ignite and burn, liberating more energy than is required to initiate the fusion reactions. NIF experiments will allow the study of physical processes at temperatures approaching 100 million K and 100 billion times atmospheric pressure. These conditions exist naturally only in the interior of stars and in nuclear weapons explosions. In the course of designing the world's most energetic laser system, a number of significant technology breakthroughs have been achieved. Research is also underway to develop a shorter pulse capability on NIF for very high power and extreme electromagnetic field research and applications. We discuss here the technology challenges and solutions that have made NIF possible, along with enhancements to NIF's design that could lead to near-exawatt power levels.

  20. The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

    Energy Technology Data Exchange (ETDEWEB)

    Moses, E I

    2002-01-11

    The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory is a $2.25B stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, 351-nm laser system. NIF is being built by the National Nuclear Security Agency and when completed will be the world's largest laser system, providing a national center to study inertial confinement fusion and the physics of extreme energy densities and pressures. In NIF up to 192 energetic laser beams will compress small fusion targets to conditions where they will ignite and burn, liberating more energy than is required to initiate the fusion reactions. NIF experiments will allow the study of physical processes at temperatures approaching 100 million K and 100 billion times atmospheric pressure. These conditions exist naturally only in the interior of stars and in nuclear weapons explosions. In the course of designing the world's most energetic laser system, a number of significant technology breakthroughs have been achieved. Research is also underway to develop a shorter pulse capability on NIF for high power applications. We discuss here the technology challenges and solutions that have made NIF possible along with enhancements to NIF's design that could lead to exawatt power levels.

  1. First Liquid Layer Inertial Confinement Fusion Implosions at the National Ignition Facility

    Science.gov (United States)

    Olson, R. E.; Leeper, R. J.; Kline, J. L.; Zylstra, A. B.; Yi, S. A.; Biener, J.; Braun, T.; Kozioziemski, B. J.; Sater, J. D.; Bradley, P. A.; Peterson, R. R.; Haines, B. M.; Yin, L.; Berzak Hopkins, L. F.; Meezan, N. B.; Walters, C.; Biener, M. M.; Kong, C.; Crippen, J. W.; Kyrala, G. A.; Shah, R. C.; Herrmann, H. W.; Wilson, D. C.; Hamza, A. V.; Nikroo, A.; Batha, S. H.

    2016-12-01

    The first cryogenic deuterium and deuterium-tritium liquid layer implosions at the National Ignition Facility (NIF) demonstrate D2 and DT layer inertial confinement fusion (ICF) implosions that can access a low-to-moderate hot-spot convergence ratio (12 NIF utilized high convergence (CR >30 ) DT ice layer implosions. Although high CR is desirable in an idealized 1D sense, it amplifies the deleterious effects of asymmetries. To date, these asymmetries prevented the achievement of ignition at the NIF and are the major cause of simulation-experiment disagreement. In the initial liquid layer experiments, high neutron yields were achieved with CRs of 12-17, and the hot-spot formation is well understood, demonstrated by a good agreement between the experimental data and the radiation hydrodynamic simulations. These initial experiments open a new NIF experimental capability that provides an opportunity to explore the relationship between hot-spot convergence ratio and the robustness of hot-spot formation during ICF implosions.

  2. ARC: A compact, high-field, fusion nuclear science facility and demonstration power plant with demountable magnets

    Energy Technology Data Exchange (ETDEWEB)

    Sorbom, B.N., E-mail: bsorbom@mit.edu; Ball, J.; Palmer, T.R.; Mangiarotti, F.J.; Sierchio, J.M.; Bonoli, P.; Kasten, C.; Sutherland, D.A.; Barnard, H.S.; Haakonsen, C.B.; Goh, J.; Sung, C.; Whyte, D.G.

    2015-11-15

    Highlights: • ARC reactor designed to have 500 MW fusion power at 3.3 m major radius. • Compact, simplified design allowed by high magnetic fields and jointed magnets. • ARC has innovative plasma physics solutions such as inboardside RF launch. • High temperature superconductors allow high magnetic fields and jointed magnets. • Liquid immersion blanket and jointed magnets greatly simplify tokamak reactor design. - Abstract: The affordable, robust, compact (ARC) reactor is the product of a conceptual design study aimed at reducing the size, cost, and complexity of a combined fusion nuclear science facility (FNSF) and demonstration fusion Pilot power plant. ARC is a ∼200–250 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has rare earth barium copper oxide (REBCO) superconducting toroidal field coils, which have joints to enable disassembly. This allows the vacuum vessel to be replaced quickly, mitigating first wall survivability concerns, and permits a single device to test many vacuum vessel designs and divertor materials. The design point has a plasma fusion gain of Q{sub p} ≈ 13.6, yet is fully non-inductive, with a modest bootstrap fraction of only ∼63%. Thus ARC offers a high power gain with relatively large external control of the current profile. This highly attractive combination is enabled by the ∼23 T peak field on coil achievable with newly available REBCO superconductor technology. External current drive is provided by two innovative inboard RF launchers using 25 MW of lower hybrid and 13.6 MW of ion cyclotron fast wave power. The resulting efficient current drive provides a robust, steady state core plasma far from disruptive limits. ARC uses an all-liquid blanket, consisting of low pressure, slowly flowing fluorine lithium beryllium (FLiBe) molten salt. The liquid blanket is low-risk technology and provides effective neutron moderation and shielding, excellent

  3. Ultrahigh field magnetic resonance and colour Doppler real-time fusion imaging of the orbit - a hybrid tool for assessment of choroidal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Uwe [University of Rostock, Department of Neurology, Rostock (Germany); Niendorf, Thoralf; Rieger, Jan [Berlin Ultrahigh Field Facility, Max-Delbrueck-Center for Molecular Medicine, Berlin (Germany); MRI.TOOLS GmbH, Berlin (Germany); Graessl, Andreas [Berlin Ultrahigh Field Facility, Max-Delbrueck-Center for Molecular Medicine, Berlin (Germany); Krueger, Paul-Christian; Langner, Soenke [University of Greifswald, Institute for Diagnostic Radiology and Neuroradiology, Greifswald (Germany); Guthoff, Rudolf F.; Stachs, Oliver [University of Rostock, Department of Ophthalmology, Rostock (Germany)

    2014-05-15

    A combination of magnetic resonance images with real-time high-resolution ultrasound known as fusion imaging may improve ophthalmologic examination. This study was undertaken to evaluate the feasibility of orbital high-field magnetic resonance and real-time colour Doppler ultrasound image fusion and navigation. This case study, performed between April and June 2013, included one healthy man (age, 47 years) and two patients (one woman, 57 years; one man, 67 years) with choroidal melanomas. All cases underwent 7.0-T magnetic resonance imaging using a custom-made ocular imaging surface coil. The Digital Imaging and Communications in Medicine volume data set was then loaded into the ultrasound system for manual registration of the live ultrasound image and fusion imaging examination. Data registration, matching and then volume navigation were feasible in all cases. Fusion imaging provided real-time imaging capabilities and high tissue contrast of choroidal tumour and optic nerve. It also allowed adding a real-time colour Doppler signal on magnetic resonance images for assessment of vasculature of tumour and retrobulbar structures. The combination of orbital high-field magnetic resonance and colour Doppler ultrasound image fusion and navigation is feasible. Multimodal fusion imaging promises to foster assessment and monitoring of choroidal melanoma and optic nerve disorders. (orig.)

  4. Cold nuclear fusion

    National Research Council Canada - National Science Library

    Huang Zhenqiang Huang Yuxiang

    2013-01-01

    ...... And with a magnetic moment of light nuclei controlled cold nuclear collide fusion, belongs to the nuclear energy research and development in the field of applied technology "cold nuclear collide fusion...

  5. Neutron Yield and Ion Temperature from DD and DT Fusion in National Ignition Facility High-Foot Implosions

    Science.gov (United States)

    Knauer, J. P.; Gatu Johnson, M.; Frenje, J. A.; Petrasso, R. D.; Caggiano, J. A.; Callahan, D. A.; Casey, D. T.; Cerjan, C. J.; Doeppner, T.; Eckart, M. J.; Grim, G. P.; Hartouni, E. P.; Hatarik, R.; Hinkel, D. E.; Hurricane, O. A.; Kritcher, A.; Le Pape, S.; Ma, T.; Munro, D. H.; Patel, P. K.; Ralph, J. E.; Sayre, D. B.; Spears, B. K.; Yeamans, C. B.; Kilkenny, J. D.

    2015-11-01

    Simultaneous measures of neutrons emitted from DT fusion implosions are postulated to provide insight into the fuel conditions during neutron emission. Neutron spectral diagnostics of National Ignition Facility ``high-foot'' implosions measure both the DT and DD fusion neutron spectra. Equivalent ion temperature is measured from the width of the DT and DD neutron emission and the respective yields from the peak areas. This work has focused on reasons for differing inferred temperatures from the DT and DD spectra and the yield ratio. Spatial and temporal averages of the DT and DD reactivities as corrections to the homogeneous and static temperature distributions are shown. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  6. A real-time algorithm for the harmonic estimation and frequency tracking of dominant components in fusion plasma magnetic diagnostics

    Science.gov (United States)

    Alves, D.; Coelho, R.; JET-EFDA Contributors

    2013-08-01

    The real-time tracking of instantaneous quantities such as frequency, amplitude, and phase of components immerse in noisy signals has been a common problem in many scientific and engineering fields such as power systems and delivery, telecommunications, and acoustics for the past decades. In magnetically confined fusion research, extracting this sort of information from magnetic signals can be of valuable assistance in, for instance, feedback control of detrimental magnetohydrodynamic modes and disruption avoidance mechanisms by monitoring instability growth or anticipating mode-locking events. This work is focused on nonlinear Kalman filter based methods for tackling this problem. Similar methods have already proven their merits and have been successfully employed in this scientific domain in applications such as amplitude demodulation for the motional Stark effect diagnostic. In the course of this work, three approaches are described, compared, and discussed using magnetic signals from the Joint European Torus tokamak plasma discharges for benchmarking purposes.

  7. Classical physics impossibility of magnetic fusion reactor with neutral beam injection at thermonuclear energies below 200 KeV

    Science.gov (United States)

    Maglich, Bogdan; Hester, Timothy; Vaucher, Alexander

    2016-10-01

    Lawson criterion was specifically derived for inertial fusion and DT gas of stable lifetime without ions and magnetic fields. It was revised with realistic parametrers. To account for the losses of unstable ions against neutralization with lifetime τ, n (t) = nτ [ 1 - exp (- t / - tτ τ) ] -> nτ for τ CT resonance regime below critical energy To, τ 10-5 , and Lawson requirement ntL 1021 i.e. not realistic. Luminosity (reaction rate for σ = 1) is that of two unstable particles each with lifetime τ: L =n2(t)v12 =n2t2v12 . In subcritical regime, L =10-10n2 forn =1014cm-3 , v 109 cms-1 = L =1027 . Which is negligible and implies a negative power flow reactor. But above T0 , atTD = 725 KeV , τ = 20 s was observed implying L =1039 i.e. massive fusion energy production.

  8. Hot Electron Propagation and Imposed Magnetic Field in Inertial Fusion Hohlraums

    CERN Document Server

    Strozzi, D J; Marinak, M M; Larson, D J; Koning, J M; Logan, B G

    2015-01-01

    Simulations with the radiation-hydrodynamics code HYDRA of a low-adiabat ignition design for the National Ignition Facility (NIF), with and without an imposed axial magnetic field, are presented. We also study superthermal, or "hot," electron dynamics with the hybrid-PIC code ZUMA, using plasma conditions from HYDRA. During the early-time laser picket, when hot electrons from the window are a concern, we find ~2E-3 of the hot electron energy in a source consistent with two-plasmon decay (80 keV temperature) in the laser entrance hole deposits in the deuterium-tritium (DT) fuel, while most of the energy deposits in the high-Z wall. A 70 Tesla field, which may improve capsule performance, magnetizes hot electrons in the hohlraum fill gas, guides them to the capsule, and increases the DT deposition 12x. Early in peak laser power, electrons with >125 keV reach the DT fuel, and those with ~185 keV deposit the largest fraction of their energy (13%) in DT. HYDRA magnetohydrodynamics (MHD) simulations with an initial...

  9. Magnetic Fields on the National Ignition Facility (MagNIF)

    Energy Technology Data Exchange (ETDEWEB)

    Mason, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Folta, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-08-12

    A magnetized target capability on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) has been investigated. Stakeholders’ needs and project feasibility analysis were considered in order to down-select from a wide variety of different potential magnetic field magnitudes and volumes. From the large range of different target platforms, laser configurations, and diagnostics configurations of interest to the stakeholders, the gas-pipe platform has been selected for the first round of magnetized target experiments. Gas pipe targets are routinely shot on the NIF and provide unique value for external collaborators. High-level project goals have been established including an experimentally relevant 20Tesla magnetic field magnitude. The field will be achieved using pulsed power-driven coils. A system architecture has been proposed. The pulsed power drive system will be located in the NIF target bay. This decision provides improved maintainability and mitigates equipment safety risks associated with explosive failure of the drive capacitor. High-level and first-level subsystem requirements have been established. Requirements have been included for two distinct coil designs – full solenoid and quasi-Helmholtz. A Failure Modes and Effects Analysis (FMEA) has been performed and documented. Additional requirements have been derived from the mitigations included in the FMEA document. A project plan is proposed. The plan includes a first phase of electromagnetic simulations to assess whether the design will meet performance requirements, then a second phase of risk mitigation projects to address the areas of highest technical risk. The duration from project kickoff to the first magnetized target shot is approximately 29 months.

  10. Recent contributions to fusion reactor design and technology development

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    The report contains a collection of 16 recent fusion technology papers on the STARFIRE Project, the study of alternate fusion fuel cycles, a maintainability study, magnet safety, neutral beam power supplies and pulsed superconducting magnets and energy transfer. This collection of papers contains contributions for Argonne National Laboratory, McDonnell Douglas Astronautics Company, General Atomic Company, The Ralph M. Parsons Company, the University of Illinois, and the University of Wisconsin. Separate abstracts are presented for each paper. (MOW)

  11. Design and fabrication of indigenous 30 kA Nb3Sn CICC for fusion relevant superconducting magnet

    Science.gov (United States)

    Raj, P.; Ghate, M.; Pradhan, S.; Singh, A.; Hussain, M. M.

    2017-02-01

    Magnet Technology Development Group” is engaged in focused research and development of indigenous fusion relevant superconducting magnet at Institute for Plasma Research in association with various R&D organizations. The fusion relevant superconducting magnet is under development using a cable in conduit conductor (CICC) with operating current of 30 kA at 12 T and 4.22 K. The 30 kA CICC has been designed in square cross-section (30 mm × 30 mm) consisting twisted Nb3Sn strands and copper strands as superconducting cable, SS316LN tubes as jacket material and SS304L foil as wrapping around the cabled strands. It has been designed on the basis of required critical design parameters, operation requirements and mechanical consideration during its fabrication. Cabling technology required for twisting of Nb3Sn and Copper strand in required configuration of cable is discussed in this paper. The effect of heat treatment on SS316LN jacket material as well as on Nb3Sn strands is mentioned in paper. 100 m long Nb3Sn based CICC is manufactured by pulled through technology on dedicated jacketing line. The manufacturing parameters and quality procedures for development of CICCs is successfully established and have been demonstrated with fabrication of 100 m Nb3Sn based CICC without any technical difficulties.

  12. Fusion Materials Research at Oak Ridge National Laboratory in Fiscal Year 2016

    Energy Technology Data Exchange (ETDEWEB)

    Wiffen, Frederick W [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Melton, Stephanie G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-12-01

    This document summarizes FY2016 activities supporting the Office of Science, Office of Fusion Energy Sciences Materials Research for MFE carried out by ORNL. The organization of the report is mainly by material type, with sections on specific technical activities.

  13. Aerial radiometric and magnetic survey: Millett National Topographic Map, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the Millett National Topographic Map NJ11-2 are presented. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets profiled data for each line are included, with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included.

  14. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    Energy Technology Data Exchange (ETDEWEB)

    L. Grisham and J.W. Kwan

    2008-08-12

    Some years ago it was suggested that halogen negative ions [1] could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons -- can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion-ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

  15. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    Energy Technology Data Exchange (ETDEWEB)

    Grisham, L.R.; Kwan, J.W.

    2008-08-01

    Some years ago it was suggested that halogen negative ions [1]could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons -- can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion-ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

  16. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy,and Related Fields

    Energy Technology Data Exchange (ETDEWEB)

    Grisham, L. R.; Kwan, J. W.

    2008-08-01

    Some years ago it was suggested that halogen negative ions could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons - can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion - ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

  17. ARC: A compact, high-field, fusion nuclear science facility and demonstration power plant with demountable magnets

    CERN Document Server

    Sorbom, B N; Palmer, T R; Mangiarotti, F J; Sierchio, J M; Bonoli, P; Kasten, C; Sutherland, D A; Barnard, H S; Haakonsen, C B; Goh, J; Sung, C; Whyte, D G

    2014-01-01

    The affordable, robust, compact (ARC) reactor conceptual design study aims to reduce the size, cost, and complexity of a combined fusion nuclear science facility (FNSF) and demonstration fusion Pilot power plant. ARC is a 270 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has rare earth barium copper oxide (REBCO) superconducting toroidal field coils, which have joints to enable disassembly. This allows the vacuum vessel to be replaced quickly, mitigating first wall survivability concerns, and permits a single device to test many vacuum vessel designs and divertor materials. The design point has a plasma fusion gain of Q_p~13.6, yet is fully non-inductive, with a modest bootstrap fraction of only ~63%. Thus ARC offers a high power gain with relatively large external control of the current profile. This highly attractive combination is enabled by the ~23 T peak field on coil with newly available REBCO superconductor technology. External cu...

  18. THE FIRST EXPERIENCE IN USING THE ULTRASOUND AND MAGNETIC RESONANCE IMAGE FUSION TECHNOLOGY IN THE DIAGNOSIS OF PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    V. V. Kapustin

    2014-07-01

    Full Text Available Objective: to study the feasibility of the image fusion technology to choose a target portion for needle biopsy in prostate cancer (PC. Subjects and methods. Ultrasound (US-magnetic resonance imaging (MRI-guided needle biopsies were made in 12 patients. All the patients underwent intravenous bolus-enhanced MRI, then MRI and US images were fused during transrectal ultrasound studies (TRUS and targets were determined to make a needle biopsy. Results. The image fusion technology allows one to concurrently assess MRI and US images in the primary diagnosis of prostate cancer and after radical prostatectomy (RPE. The MRI and transrectal images are compared with a high degree of accuracy, providing the clear positioning of the portions substantially accumulating the MRI contrast agent during real-time TRUS. Conclusion. The MRI-US image fusion procedure enables the choice of the targets to be biopsied both in the primary diagnosis of PC and in its suspected recurrence in patients after RPE. The increased accumulation of a MRI contrast agent is a major criterion for choosing a target portion.

  19. THE FIRST EXPERIENCE IN USING THE ULTRASOUND AND MAGNETIC RESONANCE IMAGE FUSION TECHNOLOGY IN THE DIAGNOSIS OF PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    V. V. Kapustin

    2010-01-01

    Full Text Available Objective: to study the feasibility of the image fusion technology to choose a target portion for needle biopsy in prostate cancer (PC. Subjects and methods. Ultrasound (US-magnetic resonance imaging (MRI-guided needle biopsies were made in 12 patients. All the patients underwent intravenous bolus-enhanced MRI, then MRI and US images were fused during transrectal ultrasound studies (TRUS and targets were determined to make a needle biopsy. Results. The image fusion technology allows one to concurrently assess MRI and US images in the primary diagnosis of prostate cancer and after radical prostatectomy (RPE. The MRI and transrectal images are compared with a high degree of accuracy, providing the clear positioning of the portions substantially accumulating the MRI contrast agent during real-time TRUS. Conclusion. The MRI-US image fusion procedure enables the choice of the targets to be biopsied both in the primary diagnosis of PC and in its suspected recurrence in patients after RPE. The increased accumulation of a MRI contrast agent is a major criterion for choosing a target portion.

  20. Fusion Energy Division: Annual progress report, period ending December 31, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, O.B. Jr.; Berry, L.A.; Sheffield, J.

    1988-11-01

    The Fusion Program of Oak Ridge National Laboratory (ORNL), a major part of the national fusion program, carries out research in nearly all areas of magnetic fusion. Collaboration among staff from ORNL, Martin Marietta Energy Systems, Inc., private industry, the academic community, and other fusion laboratories, in the United States and abroad, is directed toward the development of fusion as an energy source. This report documents the program's achievements during 1987. Issued as the annual progress report of the ORNL Fusion Energy Division, it also contains information from components of the Fusion Program that are external to the division (about 15% of the program effort). The areas addressed by the Fusion Program include the following: experimental and theoretical research on magnetic confinement concepts, engineering and physics of existing and planned devices, development and testing of diagnostic tools and techniques in support of experiments, assembly and distribution to the fusion community of databases on atomic physics and radiation effects, development and testing of technologies for heating and fueling fusion plasmas, development and testing of superconducting magnets for containing fusion plasmas, and development and testing of materials for fusion devices. Highlights from program activities are included in this report. 126 figs., 15 tabs.

  1. Fusion Energy Division progress report, 1 January 1990--31 December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, J.; Baker, C.C.; Saltmarsh, M.J.

    1994-03-01

    The Fusion Program of the Oak Ridge National Laboratory (ORNL), a major part of the national fusion program, encompasses nearly all areas of magnetic fusion research. The program is directed toward the development of fusion as an economical and environmentally attractive energy source for the future. The program involves staff from ORNL, Martin Marietta Energy systems, Inc., private industry, the academic community, and other fusion laboratories, in the US and abroad. Achievements resulting from this collaboration are documented in this report, which is issued as the progress report of the ORNL Fusion Energy Division; it also contains information from components for the Fusion Program that are external to the division (about 15% of the program effort). The areas addressed by the Fusion Program include the following: experimental and theoretical research on magnetic confinement concepts; engineering and physics of existing and planned devices, including remote handling; development and testing of diagnostic tools and techniques in support of experiments; assembly and distribution to the fusion community of databases on atomic physics and radiation effects; development and testing of technologies for heating and fueling fusion plasmas; development and testing of superconducting magnets for containing fusion plasmas; development and testing of materials for fusion devices; and exploration of opportunities to apply the unique skills, technology, and techniques developed in the course of this work to other areas (about 15% of the Division`s activities). Highlights from program activities during 1990 and 1991 are presented.

  2. 3D-FIESTA Magnetic Resonance Angiography Fusion Imaging of Distal Segment of Occluded Middle Cerebral Artery.

    Science.gov (United States)

    Kuribara, Tomoyoshi; Haraguchi, Koichi; Ogane, Kazumi; Matsuura, Nobuki; Ito, Takeo

    2015-01-01

    Middle cerebral artery (MCA) occlusion was examined with basi-parallel anatomical scanning (BPAS) using three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA), and 3D-FIESTA and magnetic resonance angiography (MRA) fusion images were created. We expected that an incidence of hemorrhagic complications due to vessel perforations would be decreased by obtaining vascular information beyond the occlusion and thus acute endovascular revascularization could be performed using such techniques. We performed revascularization for acute MCA occlusion for five patients who were admitted in our hospital from October 2012 to October 2014. Patients consisted of 1 man and 4 women with a mean age of 76.2 years (range: 59-86 years). Fusion images were created from three-dimensional time of flight (3D-TOF) MRA and 3D-FIESTA with phase cycling (3D-FIESTA-C). Then thrombectomy was performed in all the 5 patients. Merci retriever to 1 patient, Penumbra system to 1, urokinase infusion to 2, and Solitaire to 1 using such techniques. In all cases, a 3D-FIESTA-MRA fusion imaging could depict approximately clear vascular information to at least the M3 segment beyond the occlusion. And each acute revascularization was able to perform smoothly using these imaging techniques. In all cases, there was no symptomatic hemorrhagic complication. It showed that 3D-FIESTA MRA fusion imaging technique could obtain vascular information beyond the MCA occlusion. In this study, no symptomatic hemorrhagic complications were detected. It could imply that such techniques were useful not only to improve treatment efficiency but also to reduce the risk of development of hemorrhagic complications caused by vessel perforations in acute revascularization.

  3. Flywheel induction motor-generator for magnet power supply in small fusion device

    Science.gov (United States)

    Hatakeyma, S.; Yoshino, F.; Tsutsui, H.; Tsuji-Iio, S.

    2016-04-01

    A flywheel motor-generator (MG) for the toroidal field (TF) coils of a small fusion device was developed which utilizes a commercially available squirrel-cage induction motor. Advantages of the MG are comparably-long duration, quick power response, and easy implementation of power control compared with conventional capacitor-type power supply. A 55-kW MG was fabricated, and TF coils of a small fusion device were energized. The duration of the current flat-top was extended to 1 s which is much longer than those of conventional small devices (around 10-100 ms).

  4. Association Euratom - Risoe National Laboratory annual progress report 1994

    Energy Technology Data Exchange (ETDEWEB)

    Lynov, J.P.; Michelsen, P.; Singh, B.N. [eds.

    1995-06-01

    The program of the Research Unit of the Fusion Association Euratom - Risoe National Laboratory covers work in fusion plasma physics and in fusion technology. The fusion plasma physics group has activities within (a) studies of nonlinear dynamical processes in magnetized plasmas, (b) development of laser diagnostics for fusion plasmas, and (c) development of pellet injectors for fusion experiments. The activities in technology cover (a) radiation damage of fusion reactor materials and (b) water radiolysis under ITER conditions. A summary of the activities in 1994 is presented. (au) 20 ills., 19 refs.

  5. Association Euratom - Risoe National Laboratory annual progress report 1996

    Energy Technology Data Exchange (ETDEWEB)

    Lynov, J.P.; Singh, B.N. [eds.

    1997-05-01

    The programme of the Research Unit of the Fusion Association Euratom - Risoe National Laboratory covers work in fusion plasma physics and in fusion technology. The fusion plasma physics group has activities within development of laser diagnostics for fusion plasmas and studies of nonlinear dynamical processes related to electrostatic turbulence and turbulent transport in magnetized plasmas. The activities in technology cover investigations of radiation damage of fusion reactor materials. These activities contribute to the Next Step, the Long-term and the Underlying Fusion Technology programme. A summary is presented of the results obtained in the Research Unit during 1996. (au) 5 tabs., 25 ills., 11 refs.

  6. Summary of the International Workshop on Magnetic Fusion Energy (MFE) Roadmapping in the ITER Era; 7-10 September 2011, Princeton, NJ, USA

    Science.gov (United States)

    Neilson, G. H.; Federici, G.; Li, J.; Maisonnier, D.; Wolf, R.

    2012-04-01

    With the ITER project now well under way, the countries engaged in fusion research are planning, with renewed intensity, the research and major facilities needed to develop the science and technology for harnessing fusion energy. The Workshop on MFE Roadmapping in the ITER Era was organized to provide a timely forum for an international exchange of technical information and strategic perspectives on how best to tackle the remaining challenges leading to a magnetic fusion DEMO, a nuclear fusion device or devices with a level of physics and technology integration necessary to cover the essential elements of a commercial fusion power plant. Presentations addressed issues under four topics: (1) Perspectives on DEMO and the roadmap to DEMO; (2) Technology; (3) Physics-Technology integration and optimization; and (4) Major facilities on the path to DEMO. Participants identified a set of technical issues of high strategic importance, where the development strategy strongly influences the overall roadmap, and where there are divergent understandings in the world community, namely (1) the assumptions used in fusion design codes, (2) the strategy for fusion materials development, (3) the strategy for blanket development, (4) the strategy for plasma exhaust solution development and (5) the requirements and state of readiness for next-step facility options. It was concluded that there is a need to continue and to focus the international discussion concerning the scientific and technical issues that determine the fusion roadmap, and it was suggested that an international activity be organized under appropriate auspices to foster international cooperation on these issues.

  7. Kinetic transport in a magnetically confined and flux-constrained fusion plasma; Transport cinetique dans un plasma de fusion magnetique a flux force

    Energy Technology Data Exchange (ETDEWEB)

    Darmet, G

    2007-11-15

    This work deals with the kinetic transport in a fusion plasma magnetically confined and flux-constrained. The author proposes a new interpretation of the dynamics of zonal flows. The model that has been studied is a gyrokinetic model reduced to the transport of trapped ions. The inter-change stability that is generated allows the study of the kinetic transport of trapped ions. This model has a threshold instability and can be simulated over a few tens confining time for either thermal bath constraint or flux constraint. For thermal baths constraint, the simulation shows a metastable state where zonal flows are prevailing while turbulence is non-existent. In the case of a flux-constraint, zonal flows appear and relax by exchanging energy with system's kinetic energy and turbulence energy. The competition between zonal flows and turbulence can be then simulated by a predator-prey model. 2 regimes can be featured out: an improved confining regime where zonal flows dominate transport and a turbulent regime where zonal flows and turbulent transport are of the same magnitude order. We show that flux as well as the Reynolds tensor play an important role in the dynamics of the zonal flows and that the gyrokinetic description is relevant for all plasma regions. (A.C.)

  8. Millimeter-wave imaging of magnetic fusion plasmas: technology innovations advancing physics understanding

    Science.gov (United States)

    Wang, Y.; Tobias, B.; Chang, Y.-T.; Yu, J.-H.; Li, M.; Hu, F.; Chen, M.; Mamidanna, M.; Phan, T.; Pham, A.-V.; Gu, J.; Liu, X.; Zhu, Y.; Domier, C. W.; Shi, L.; Valeo, E.; Kramer, G. J.; Kuwahara, D.; Nagayama, Y.; Mase, A.; Luhmann, N. C., Jr.

    2017-07-01

    Electron cyclotron emission (ECE) imaging is a passive radiometric technique that measures electron temperature fluctuations; and microwave imaging reflectometry (MIR) is an active radar imaging technique that measures electron density fluctuations. Microwave imaging diagnostic instruments employing these techniques have made important contributions to fusion science and have been adopted at major fusion facilities worldwide including DIII-D, EAST, ASDEX Upgrade, HL-2A, KSTAR, LHD, and J-TEXT. In this paper, we describe the development status of three major technological advancements: custom mm-wave integrated circuits (ICs), digital beamforming (DBF), and synthetic diagnostic modeling (SDM). These have the potential to greatly advance microwave fusion plasma imaging, enabling compact and low-noise transceiver systems with real-time, fast tracking ability to address critical fusion physics issues, including ELM suppression and disruptions in the ITER baseline scenario, naturally ELM-free states such as QH-mode, and energetic particle confinement (i.e. Alfvén eigenmode stability) in high-performance regimes that include steady-state and advanced tokamak scenarios. Furthermore, these systems are fully compatible with today’s most challenging non-inductive heating and current drive systems and capable of operating in harsh environments, making them the ideal approach for diagnosing long-pulse and steady-state tokamaks.

  9. REQUIREMENTS FOR COLLISION DATA ON THE SPECIES HELIUM, BERYLLIUM AND BORON IN MAGNETIC CONFINEMENT FUSION

    NARCIS (Netherlands)

    SUMMERS, HP; VONHELLERMANN, M; DEHEER, FJ; HOEKSTRA, R

    1992-01-01

    Requirements for collision data on helium, beryllium and boron are reviewed in the light of the directions of present and planned tokamak fusion experiments. The occurrence of the atoms and ions of these species and their roles in plasma behaviour and diagnostic measurements are described. Special e

  10. The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

    Energy Technology Data Exchange (ETDEWEB)

    Wuest, C

    2001-10-29

    The National Ignition Facility (NIF) currently under construction at the University of California Lawrence Livermore National Laboratory (LLNL) is a 192-beam, 1.8-megajoule, 500-terawatt, 351-nm laser for inertial confinement fusion (ICF) and high-energy-density experimental studies. NIF is being built by the Department of Energy and the National Nuclear Security Agency (NNSA) to provide an experimental test bed for the U.S. Stockpile Stewardship Program to ensure the country's nuclear deterrent without underground nuclear testing. The experimental program will encompass a wide range of physical phenomena from fusion energy production to materials science. Of the roughly 700 shots available per year, about 10% will be dedicated to basic science research. Laser hardware is modularized into line replaceable units (LRUs) such as deformable mirrors, amplifiers, and multi-function sensor packages that are operated by a distributed computer control system of nearly 60,000 control points. The supervisory control room presents facility-wide status and orchestrates experiments using operating parameters predicted by physics models. A network of several hundred front-end processors (FEPs) implements device control. The object-oriented software system is implemented in the Ada and Java languages and emphasizes CORBA distribution of reusable software objects. NIF is currently scheduled to provide first light in 2004 and will be completed in 2008.

  11. Inertial Fusion Energy Development: What is Needed and What will be Learned at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, W.J.

    1999-10-21

    Successful development of inertial fusion energy (IFE) requires that many technical issues be resolved. Separability of drivers, targets, chambers and other IFE power plant subsystems allows resolution of many of these issues in off-line facilities and programs. Periodically, major integrated facilities give a snapshot of the rate of progress toward the ultimate solutions. The National Ignition Facility (NIF) and Laser Megajoule (LMJ) are just such integrating facilities. This paper reviews the status of IFE development and projects what will be learned from the NIF and LMJ.

  12. Safety and reliability in superconducting MHD magnets

    Energy Technology Data Exchange (ETDEWEB)

    Laverick, C.; Powell, J.; Hsieh, S.; Reich, M.; Botts, T.; Prodell, A.

    1979-07-01

    This compilation adapts studies on safety and reliability in fusion magnets to similar problems in superconducting MHD magnets. MHD base load magnet requirements have been identified from recent Francis Bitter National Laboratory reports and that of other contracts. Information relevant to this subject in recent base load magnet design reports for AVCO - Everett Research Laboratories and Magnetic Corporation of America is included together with some viewpoints from a BNL workshop on structural analysis needed for superconducting coils in magnetic fusion energy. A summary of design codes used in large bubble chamber magnet design is also included.

  13. Overview of recent tritium target filling, layering, and material testing at Los Alamos national laboratory in support of inertial fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ebey, P. S.; Dole, J. M.; Geller, D. A.; Hoffer, J. K.; Morris, J.; Nobile, A.; Schoonover, J. R.; Wilson, D. [MS-C927, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Bonino, M.; Harding, D.; Sangster, C.; Shmayda, W. [Laboratory for Laser Energetics LLE, Univ. of Rochester, 250 East River Road, Rochester, NY 14623 (United States); Nikroo, A.; Sheliak, J. D. [General Atomics GA (United States); Burmann, J.; Cook, B.; Letts, S.; Sanchez, J. [Lawrence Livermore National Laboratory LLNL (United States)

    2008-07-15

    The Tritium Science and Engineering (AET-3) Group at Los Alamos National Laboratory (LANL) performs a variety of activities to support Inertial Fusion (IF) research - both to further fundamental fusion science and to develop technologies in support of Inertial Fusion Energy (IFE) power generation. Inertial fusion ignition target designs have a smooth spherical shell of cryogenic Deuterium-Tritium (DT) solid contained within a metal or plastic shell that is a few mm in diameter. Fusion is attained by imploding these shells under the symmetric application of energy beams. For IFE targets the DT solid must also survive the process of injecting it into the power plant reactor. Non-ignition IF targets often require a non-cryogenic DT gas fill of a glass or polymeric shell. In this paper an overview will be given of recent LANL activities to study cryogenic DT layering, observe tritium exposure effects on IF relevant materials, and fill targets in support of IF implosion experiments. (authors)

  14. Self-organized criticality and the dynamics of near-marginal turbulent transport in magnetically confined fusion plasmas

    Science.gov (United States)

    Sanchez, R.; Newman, D. E.

    2015-12-01

    The high plasma temperatures expected at reactor conditions in magnetic confinement fusion toroidal devices suggest that near-marginal operation could be a reality in future devices and reactors. By near-marginal it is meant that the plasma profiles might wander around the local critical thresholds for the onset of instabilities. Self-organized criticality (SOC) was suggested in the mid 1990s as a more proper paradigm to describe the dynamics of tokamak plasma transport in near-marginal conditions. It advocated that, near marginality, the evolution of mean profiles and fluctuations should be considered simultaneously, in contrast to the more common view of a large separation of scales existing between them. Otherwise, intrinsic features of near-marginal transport would be missed, that are of importance to understand the properties of energy confinement. In the intervening 20 years, the relevance of the idea of SOC for near-marginal transport in fusion plasmas has transitioned from an initial excessive hype to the much more realistic standing of today, which we will attempt to examine critically in this review paper. First, the main theoretical ideas behind SOC will be described. Secondly, how they might relate to the dynamics of near-marginal transport in real magnetically confined plasmas will be discussed. Next, we will review what has been learnt about SOC from various numerical studies and what it has meant for the way in which we do numerical simulation of fusion plasmas today. Then, we will discuss the experimental evidence available from the several experiments that have looked for SOC dynamics in fusion plasmas. Finally, we will conclude by identifying the various problems that still remain open to investigation in this area. Special attention will be given to the discussion of frequent misconceptions and ongoing controversies. The review also contains a description of ongoing efforts that seek effective transport models better suited than traditional

  15. Fast neutron spectrometry with organic scintillators applied to magnetic fusion experiments

    CERN Document Server

    Kaschuck, Y A; Trykov, L A; Semenov, V P

    2002-01-01

    Neutron spectrometry with NE213 liquid scintillators is commonly used in thermonuclear fusion experiments to measure the 2.45 and 14.1 MeV neutron flux. We present the unfolded neutron spectrum, which was accumulated during several ohmic deuterium plasma discharges in the Frascati Tokamak Upgrade using a 2''x2'' NE213 scintillator. In this paper, we review the application of organic scintillator neutron spectrometers to tokamaks, focusing in particular on the comparison between NE213 and stilbene scintillators. Various aspects of the calibration technique and neutron spectra unfolding procedure are considered in the context of their application for fusion neutron spectrometry. Testing and calibration measurements have been carried out using D-D and D-T neutron generator facilities with both NE213 and stilbene scintillators. The main result from these measurements is that stilbene scintillator has better neutron energy resolution than NE213. Our stilbene detector could be used for the determination of the ion ...

  16. Proceedings of the workshop on structural analysis needs for magnetic fusion energy superconducting magnets: a technical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Reich, M.; Lehner, J.; Powell, J.; Bezler, P.

    1976-01-01

    The technical portions of the meeting were divided into three major sessions as follows: (1) Review of methods being presently used by the MFE community for structural evaluation of current designs. (2) Future structural analysis needs. (3) Open discussions dealing with adequacy of present methods, the improvements needed for MFE magnet structural analysis, and the establishment of an MFE magnet structural advisory group. Summaries of the individual talks are presented.

  17. Fusion Energy Division annual progress report, period ending December 31, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, J.; Baker, C.C.; Saltmarsh, M.J.

    1991-07-01

    The Fusion Program of Oak Ridge National Laboratory (ORNL) carries out research in most areas of magnetic confinement fusion. The program is directed toward the development of fusion as an energy source and is a strong and vital component of both the US fusion program and the international fusion community. Issued as the annual progress report of the ORNL Fusion Energy Division, this report also contains information from components of the Fusion Program that are carried out by other ORNL organizations (about 15% of the program effort). The areas addressed by the Fusion Program and discussed in this report include the following: Experimental and theoretical research on magnetic confinement concepts, engineering and physics of existing and planned devices, including remote handling, development and testing of diagnostic tools and techniques in support of experiments, assembly and distribution to the fusion community of databases on atomic physics and radiation effects, development and testing of technologies for heating and fueling fusion plasmas, development and testing of superconducting magnets for containing fusion plasmas, development and testing of materials for fusion devices, and exploration of opportunities to apply the unique skills, technology, and techniques developed in the course of this work to other areas. Highlights from program activities are included in this report.

  18. Three-dimensional reconstruction of subject-specific knee joint using computed tomography and magnetic resonance imaging image data fusions.

    Science.gov (United States)

    Dong, Yuefu; Mou, Zhifang; Huang, Zhenyu; Hu, Guanghong; Dong, Yinghai; Xu, Qingrong

    2013-10-01

    Three-dimensional reconstruction of human body from a living subject can be considered as the first step toward promoting virtual human project as a tool in clinical applications. This study proposes a detailed protocol for building subject-specific three-dimensional model of knee joint from a living subject. The computed tomography and magnetic resonance imaging image data of knee joint were used to reconstruct knee structures, including bones, skin, muscles, cartilages, menisci, and ligaments. They were fused to assemble the complete three-dimensional knee joint. The procedure was repeated three times with respect to three different methods of reference landmarks. The accuracy of image fusion in accordance with different landmarks was evaluated and compared with each other. The complete three-dimensional knee joint, which included 21 knee structures, was accurately developed. The choice of external or anatomical landmarks was not crucial to improve image fusion accuracy for three-dimensional reconstruction. Further work needs to be done to explore the value of the reconstructed three-dimensional knee joint for its biomechanics and kinematics.

  19. Simulation of self-generated magnetic fields in an inertial fusion hohlraum environment

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, W. A.; Koning, J. M.; Strozzi, D. J.; Hinkel, D. E.; Berzak Hopkins, L. F.; Jones, O. S.; Rosen, M. D.

    2017-05-01

    We present radiation-hydrodynamic simulations of self-generated magnetic field in a hohlraum, which show an increased temperature in large regions of the underdense fill. Non-parallel gradients in electron density and temperature in a laser-heated plasma give rise to a self-generated field by the “Biermann battery” mechanism. Here, HYDRA simulations of three hohlraum designs on the National Ignition Facility are reported, which use a partial magnetohydrodynamic (MHD) description that includes the self-generated source term, resistive dissipation, and advection of the field due to both the plasma flow and the Nernst term. Anisotropic electron heat conduction parallel and perpendicular to the field is included, but not the Righi-Leduc heat flux. The field strength is too small to compete significantly with plasma pressure, but affects plasma conditions by reducing electron heat conduction perpendicular to the field. Significant reductions in heat flux can occur, especially for high Z plasma, at modest values of the Hall parameter, Ωeτei≲1Ωeτei≲1, where Ωe=eB/mecΩe=eB/mec and τei is the electron-ion collision time. The inclusion of MHD in the simulations leads to 1 keV hotter electron temperatures in the laser entrance hole and high-Z wall blowoff, which reduces inverse-bremsstrahlung absorption of the laser beam. This improves propagation of the inner beams pointed at the hohlraum equator, resulting in a symmetry shift of the resulting capsule implosion towards a more prolate shape. The time of peak x-ray production in the capsule shifts later by only 70 ps (within experimental uncertainty), but a decomposition of the hotspot shape into Legendre moments indicates a shift of P2/P0P2/P0 by ~20%. This indicates that MHD cannot explain why simulated x-ray drive exceeds measured levels, but may be partially responsible for failures to correctly model the symmetry.

  20. Fast Ignition Thermonuclear Fusion: Enhancement of the Pellet Gain by the Colossal-Magnetic-Field Shells

    Science.gov (United States)

    Stefan, V. Alexander

    2013-10-01

    The fast ignition fusion pellet gain can be enhanced by a laser generated B-field shell. The B-field shell, (similar to Earth's B-field, but with the alternating B-poles), follows the pellet compression in a frozen-in B-field regime. A properly designed laser-pellet coupling can lead to the generation of a B-field shell, (up to 100 MG), which inhibits electron thermal transport and confines the alpha-particles. In principle, a pellet gain of few-100s can be achieved in this manner. Supported in part by Nikola Tesla Labs, Stefan University, 1010 Pearl, La Jolla, CA 92038-1007.

  1. Effect of Fuelling Depth on the Fusion Performance and Particle Confinement of a Fusion Reactor

    Science.gov (United States)

    Wang, Shijia; Wang, Shaojie

    2016-12-01

    The fusion performance and particle confinement of an international thermonuclear experimental reactor (ITER)-like fusion device have been modeled by numerically solving the energy transport equation and the particle transport equation. The effect of fuelling depth has been investigated. The plasma is primarily heated by the fusion produced alpha particles and the loss process of particles and energy in the scrape-off layer has been taken into account. To study the effect of fuelling depth on fusion performance, the ITERH-98P(y,2) scaling law has been used to evaluate the transport coefficients. It is shown that the particle confinement and fusion performance are significantly dependent on the fuelling depth. Deviation of 10% of the minor radius on fuelling depth can make the particle confinement change by ∼ 61% and the fusion performance change by ∼ 108%. The enhancement of fusion performance is due to the better particle confinement induced by deeper particle fuelling. supported by National Natural Science Foundation of China (Nos. 11175178 and 11375196) and the National Magnetic Confinement Fusion Science Program of China (No. 2014GB113000)

  2. The superconducting magnet system for the WENDELSTEIN 7-X fusion experiment; Das supraleitende Magnetsystem fuer das Fusionsexperiment WENDELSTEIN 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Sapper, J.

    1995-05-01

    In devices of the TOKAMAK type (JET/Culham, GB, and TFTR/Princeton Laboratory, U.S.A.), successful plasma ignition was achieved, and fusion-induced generation of electricity of some megawatts, for a period of seconds. Experiments of the next generation will tackle the problems of electricity generation sustained over longer periods, for which the STELLARATOR machines are the device of choice, as these, other than the TOKAMAKS, do not require generation of plasma ring currents between 10 and 20 MA. The magnet system in the STELLARATOR devices has to be a superconducting magnet system. At present, bench-scale LT superconductors are available made of materials on the basis of NbTi or Nb{sub 3}Sn, which are applied according to system configuration ( induction at the conductor, current density, temperature, alternating magnetic field load). The paper explains the magnet system intended for use in the planned STELLARATOR WENDELSTEIN 7-X experiments at IPP, Garching. (orig./MM) [Deutsch] In Maschinen des Typs TOKAMAK (JET/Culham, GB und TFTR/Princeton Laboratory, USA) wurde bei den genannten technischen Gegebenheiten die Zuendbedingung erreicht und Fusionsleistung im Megawattbereich fuer einige Sekunden erzeugt. Experimente der naechsten Generation muessen den Dauerbetrieb anstreben, wobei hierfuer Maschinen des Typs STELLARATOR besonders geeignet sind, weil Massnahmen zur Erzeugung eines Plasmaringstromes von 10 bis 20 MA - wie sie fuer TOKAMAKS noetig werden - entfallen koennen. Das Magnetsystem muss - wegen des andernfalls hohen Dauerleistungsbedarfs - supraleitend ausgefuehrt werden. Hierfuer stehen heute im technischen Massstab Niedertemperatursupraleiter auf der Basis von NbTi oder Nb{sub 3}Sn zur Verfuegung, die abhaengig von den geforderten Einsatzbedingungen (Induktion am Leiter, Stromdichte, Temperatur und Wechselfeldbelastung) zum Einsatz gelangen. Im folgenden ist das fuer den geplanten STELLARATOR WENDELSTEIN 7-X (IPP, Garching) vorgesehene Magnetsystem

  3. Compendium of computer codes for the researcher in magnetic fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    Porter, G.D. (ed.)

    1989-03-10

    This is a compendium of computer codes, which are available to the fusion researcher. It is intended to be a document that permits a quick evaluation of the tools available to the experimenter who wants to both analyze his data, and compare the results of his analysis with the predictions of available theories. This document will be updated frequently to maintain its usefulness. I would appreciate receiving further information about codes not included here from anyone who has used them. The information required includes a brief description of the code (including any special features), a bibliography of the documentation available for the code and/or the underlying physics, a list of people to contact for help in running the code, instructions on how to access the code, and a description of the output from the code. Wherever possible, the code contacts should include people from each of the fusion facilities so that the novice can talk to someone ''down the hall'' when he first tries to use a code. I would also appreciate any comments about possible additions and improvements in the index. I encourage any additional criticism of this document. 137 refs.

  4. The magnetic recoil spectrometer (MRSt) for time-resolved measurements of the neutron spectrum at the National Ignition Facility (NIF).

    Science.gov (United States)

    Frenje, J A; Hilsabeck, T J; Wink, C W; Bell, P; Bionta, R; Cerjan, C; Gatu Johnson, M; Kilkenny, J D; Li, C K; Séguin, F H; Petrasso, R D

    2016-11-01

    The next-generation magnetic recoil spectrometer for time-resolved measurements of the neutron spectrum has been conceptually designed for the National Ignition Facility. This spectrometer, called MRSt, represents a paradigm shift in our thinking about neutron spectrometry for inertial confinement fusion applications, as it will provide simultaneously information about the burn history and time evolution of areal density (ρR), apparent ion temperature (Ti), yield (Yn), and macroscopic flows during burn. From this type of data, an assessment of the evolution of the fuel assembly, hotspot, and alpha heating can be made. According to simulations, the MRSt will provide accurate data with a time resolution of ∼20 ps and energy resolution of ∼100 keV for total neutron yields above ∼10(16). At lower yields, the diagnostic will be operated at a higher-efficiency, lower-energy-resolution mode to provide a time resolution of ∼20 ps.

  5. The magnetic recoil spectrometer (MRSt) for time-resolved measurements of the neutron spectrum at the National Ignition Facility (NIF)

    Science.gov (United States)

    Frenje, J. A.; Hilsabeck, T. J.; Wink, C. W.; Bell, P.; Bionta, R.; Cerjan, C.; Gatu Johnson, M.; Kilkenny, J. D.; Li, C. K.; Séguin, F. H.; Petrasso, R. D.

    2016-11-01

    The next-generation magnetic recoil spectrometer for time-resolved measurements of the neutron spectrum has been conceptually designed for the National Ignition Facility. This spectrometer, called MRSt, represents a paradigm shift in our thinking about neutron spectrometry for inertial confinement fusion applications, as it will provide simultaneously information about the burn history and time evolution of areal density (ρR), apparent ion temperature (Ti), yield (Yn), and macroscopic flows during burn. From this type of data, an assessment of the evolution of the fuel assembly, hotspot, and alpha heating can be made. According to simulations, the MRSt will provide accurate data with a time resolution of ˜20 ps and energy resolution of ˜100 keV for total neutron yields above ˜1016. At lower yields, the diagnostic will be operated at a higher-efficiency, lower-energy-resolution mode to provide a time resolution of ˜20 ps.

  6. The magnetic recoil spectrometer (MRSt) for time-resolved measurements of the neutron spectrum at the National Ignition Facility (NIF)

    Energy Technology Data Exchange (ETDEWEB)

    Frenje, J. A., E-mail: jfrenje@psfc.mit.edu; Wink, C. W.; Gatu Johnson, M.; Li, C. K.; Séguin, F. H.; Petrasso, R. D. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Hilsabeck, T. J.; Kilkenny, J. D. [General Atomics, San Diego, California 92186 (United States); Bell, P.; Bionta, R.; Cerjan, C. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-11-15

    The next-generation magnetic recoil spectrometer for time-resolved measurements of the neutron spectrum has been conceptually designed for the National Ignition Facility. This spectrometer, called MRSt, represents a paradigm shift in our thinking about neutron spectrometry for inertial confinement fusion applications, as it will provide simultaneously information about the burn history and time evolution of areal density (ρR), apparent ion temperature (T{sub i}), yield (Y{sub n}), and macroscopic flows during burn. From this type of data, an assessment of the evolution of the fuel assembly, hotspot, and alpha heating can be made. According to simulations, the MRSt will provide accurate data with a time resolution of ∼20 ps and energy resolution of ∼100 keV for total neutron yields above ∼10{sup 16}. At lower yields, the diagnostic will be operated at a higher-efficiency, lower-energy-resolution mode to provide a time resolution of ∼20 ps.

  7. Finite Element Modelling of a Field-Sensed Magnetic Suspended System for Accurate Proximity Measurement Based on a Sensor Fusion Algorithm with Unscented Kalman Filter

    Directory of Open Access Journals (Sweden)

    Amor Chowdhury

    2016-09-01

    Full Text Available The presented paper describes accurate distance measurement for a field-sensed magnetic suspension system. The proximity measurement is based on a Hall effect sensor. The proximity sensor is installed directly on the lower surface of the electro-magnet, which means that it is very sensitive to external magnetic influences and disturbances. External disturbances interfere with the information signal and reduce the usability and reliability of the proximity measurements and, consequently, the whole application operation. A sensor fusion algorithm is deployed for the aforementioned reasons. The sensor fusion algorithm is based on the Unscented Kalman Filter, where a nonlinear dynamic model was derived with the Finite Element Modelling approach. The advantage of such modelling is a more accurate dynamic model parameter estimation, especially in the case when the real structure, materials and dimensions of the real-time application are known. The novelty of the paper is the design of a compact electro-magnetic actuator with a built-in low cost proximity sensor for accurate proximity measurement of the magnetic object. The paper successively presents a modelling procedure with the finite element method, design and parameter settings of a sensor fusion algorithm with Unscented Kalman Filter and, finally, the implementation procedure and results of real-time operation.

  8. Finite Element Modelling of a Field-Sensed Magnetic Suspended System for Accurate Proximity Measurement Based on a Sensor Fusion Algorithm with Unscented Kalman Filter.

    Science.gov (United States)

    Chowdhury, Amor; Sarjaš, Andrej

    2016-09-15

    The presented paper describes accurate distance measurement for a field-sensed magnetic suspension system. The proximity measurement is based on a Hall effect sensor. The proximity sensor is installed directly on the lower surface of the electro-magnet, which means that it is very sensitive to external magnetic influences and disturbances. External disturbances interfere with the information signal and reduce the usability and reliability of the proximity measurements and, consequently, the whole application operation. A sensor fusion algorithm is deployed for the aforementioned reasons. The sensor fusion algorithm is based on the Unscented Kalman Filter, where a nonlinear dynamic model was derived with the Finite Element Modelling approach. The advantage of such modelling is a more accurate dynamic model parameter estimation, especially in the case when the real structure, materials and dimensions of the real-time application are known. The novelty of the paper is the design of a compact electro-magnetic actuator with a built-in low cost proximity sensor for accurate proximity measurement of the magnetic object. The paper successively presents a modelling procedure with the finite element method, design and parameter settings of a sensor fusion algorithm with Unscented Kalman Filter and, finally, the implementation procedure and results of real-time operation.

  9. Simulating the magnetized liner inertial fusion plasma confinement with smaller-scale experiments [Simulating the MagLIF plasma confinement with smaller-scale experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cuneo, M. E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Herrmann, M. C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sinars, D. B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Slutz, S. A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2012-06-20

    The recently proposed magnetized liner inertial fusion approach to a Z-pinch driven fusion [Slutz et al., Phys. Plasmas17, 056303 (2010)] is based on the use of an axial magnetic field to provide plasma thermal insulation from the walls of the imploding liner. The characteristic plasma transport regimes in the proposed approach cover parameter domains that have not been studied yet in either magnetic confinement or inertial confinement experiments. In this article, an analysis is presented of the scalability of the key physical processes that determine the plasma confinement. The dimensionless scaling parameters are identified and conclusion is drawn that the plasma behavior in scaled-down experiments can correctly represent the full-scale plasma, provided these parameters are approximately the same in two systems. Furthermore, this observation is important in that smaller-scale experiments typically have better diagnostic access and more experiments per year are possible.

  10. Survey of Laser Markets Relevant to Inertial Fusion Energy Drivers, information for National Research Council

    Energy Technology Data Exchange (ETDEWEB)

    Bayramian, A J; Deri, R J; Erlandson, A C

    2011-02-24

    Development of a new technology for commercial application can be significantly accelerated by leveraging related technologies used in other markets. Synergies across multiple application domains attract research and development (R and D) talent - widening the innovation pipeline - and increases the market demand in common components and subsystems to provide performance improvements and cost reductions. For these reasons, driver development plans for inertial fusion energy (IFE) should consider the non-fusion technology base that can be lveraged for application to IFE. At this time, two laser driver technologies are being proposed for IFE: solid-state lasers (SSLs) and KrF gas (excimer) lasers. This document provides a brief survey of organizations actively engaged in these technologies. This is intended to facilitate comparison of the opportunities for leveraging the larger technical community for IFE laser driver development. They have included tables that summarize the commercial organizations selling solid-state and KrF lasers, and a brief summary of organizations actively engaged in R and D on these technologies.

  11. Superconducting focusing quadrupoles for heavy ion fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sabbi, G.L.; Faltens, A.; Leitner, M.; Lietzke, A.; Seidl, P.; Barnard, J.; Lund, S.; Martovetsky, N.; Gung, C.; Minervini, J.; Radovinsky, A.; Schultz, J.; Meinke, R.

    2003-05-01

    The Heavy Ion Fusion (HIF) Program is developing superconducting focusing magnets for both near-term experiments and future driver accelerators. In particular, single bore quadrupoles have been fabricated and tested for use in the High Current Experiment (HCX) at Lawrence Berkeley National Laboratory (LBNL). The next steps involve the development of magnets for the planned Integrated Beam Experiment (IBX) and the fabrication of the first prototype multi-beam focusing arrays for fusion driver accelerators. The status of the magnet R&D program is reported, including experimental requirements, design issues and test results.

  12. Numerical analysis of applied magnetic field dependence in Malmberg-Penning Trap for compact simulator of energy driver in heavy ion fusion

    Science.gov (United States)

    Sato, T.; Park, Y.; Soga, Y.; Takahashi, K.; Sasaki, T.; Kikuchi, T.; Harada, Nob

    2016-05-01

    To simulate a pulse compression process of space charge dominated beams in heavy ion fusion, we have demonstrated a multi-particle numerical simulation as an equivalent beam using the Malmberg-Penning trap device. The results show that both transverse and longitudinal velocities as a function of external magnetic field strength are increasing during the longitudinal compression. The influence of space-charge effect, which is related to the external magnetic field, was observed as the increase of high velocity particles at the weak external magnetic field.

  13. Microinstability properties of negative magnetic shear discharges in the Tokamak Fusion Test Reactor and DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Rewoldt, G.; Tang, W.M. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.; Lao, L.L. [General Atomics, San Diego, CA (United States)

    1997-03-01

    The microinstability properties of discharges with negative (reversed) magnetic shear in the Tokamak Fusion Test Reactor (TFTR) and DIII-D experiments with and without confinement transitions are investigated. A comprehensive kinetic linear eigenmode calculation employing the ballooning representation is employed with experimentally measured profile data, and using the corresponding numerically computed magnetohydrodynamic (MHD) equilibria. The instability considered is the toroidal drift mode (trapped-electron-{eta}{sub i} mode). A variety of physical effects associated with differing q-profiles are explained. In addition, different negative magnetic shear discharges at different times in the discharge for TFTR and DIII-D are analyzed. The effects of sheared toroidal rotation, using data from direct spectroscopic measurements for carbon, are analyzed using comparisons with results from a two-dimensional calculation. Comparisons are also made for nonlinear stabilization associated with shear in E{sub r}/RB{sub {theta}}. The relative importance of changes in different profiles (density, temperature, q, rotation, etc.) on the linear growth rates is considered.

  14. The role of the boundary plasma in defining the viability of a magnetic fusion reactor: A review

    Science.gov (United States)

    Whyte, Dennis

    2012-10-01

    The boundary of magnetic confinement devices, from the pedestal through to the surrounding surfaces, encompasses an enormous range of plasma and material physics, and their integrated coupling. It is becoming clear that due to fundamental limits of plasma stability and material response the boundary will largely define the viability of an MFE reactor. However we face an enormous knowledge deficit in stepping from present devices and ITER towards a demonstration power plant. We review the boundary and plasma-material interaction (PMI) research required to address this deficit as well as related theoretical/scaling methods for extending present results to future devices. The research activities and gaps are reviewed and organized to three major axes of challenges: power density, plasma duration, and material temperature. The boundary can also be considered a multi-scale system of coupled plasma and material science regulated through the non-linear interface of the sheath. Measurement, theory and modeling across these scales are reviewed. Dimensionless parameters, often used to organized core plasma transport on similarity arguments, can be extended to the boundary plasma, plasma-surface interactions and material response. The scaling methodology suggests intriguing ways forward to prescribe and understand the boundary issues of an eventual reactor in intermediate size devices. Finally, proposed technology and science innovations towards solving the extreme PMI/boundary challenges of magnetic fusion energy will be reviewed.

  15. Instability growth for magnetized liner inertial fusion seeded by electro-thermal, electro-choric, and material strength effects

    Energy Technology Data Exchange (ETDEWEB)

    Pecover, J. D.; Chittenden, J. P. [The Centre for Inertial Fusion Studies, The Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)

    2015-10-15

    A critical limitation of magnetically imploded systems such as magnetized liner inertial fusion (MagLIF) [Slutz et al., Phys. Plasmas 17, 056303 (2010)] is the magneto-Rayleigh-Taylor (MRT) instability which primarily disrupts the outer surface of the liner. MagLIF-relevant experiments have showed large amplitude multi-mode MRT instability growth growing from surface roughness [McBride et al., Phys. Rev. Lett. 109, 135004 (2012)], which is only reproduced by 3D simulations using our MHD code Gorgon when an artificially azimuthally correlated initialisation is added. We have shown that the missing azimuthal correlation could be provided by a combination of the electro-thermal instability (ETI) and an “electro-choric” instability (ECI); describing, respectively, the tendency of current to correlate azimuthally early in time due to temperature dependent Ohmic heating; and an amplification of the ETI driven by density dependent resistivity around vapourisation. We developed and implemented a material strength model in Gorgon to improve simulation of the solid phase of liner implosions which, when applied to simulations exhibiting the ETI and ECI, gave a significant increase in wavelength and amplitude. Full circumference simulations of the MRT instability provided a significant improvement on previous randomly initialised results and approached agreement with experiment.

  16. Instability growth for magnetized liner inertial fusion seeded by electro-thermal, electro-choric, and material strength effects

    Science.gov (United States)

    Pecover, J. D.; Chittenden, J. P.

    2015-10-01

    A critical limitation of magnetically imploded systems such as magnetized liner inertial fusion (MagLIF) [Slutz et al., Phys. Plasmas 17, 056303 (2010)] is the magneto-Rayleigh-Taylor (MRT) instability which primarily disrupts the outer surface of the liner. MagLIF-relevant experiments have showed large amplitude multi-mode MRT instability growth growing from surface roughness [McBride et al., Phys. Rev. Lett. 109, 135004 (2012)], which is only reproduced by 3D simulations using our MHD code Gorgon when an artificially azimuthally correlated initialisation is added. We have shown that the missing azimuthal correlation could be provided by a combination of the electro-thermal instability (ETI) and an "electro-choric" instability (ECI); describing, respectively, the tendency of current to correlate azimuthally early in time due to temperature dependent Ohmic heating; and an amplification of the ETI driven by density dependent resistivity around vapourisation. We developed and implemented a material strength model in Gorgon to improve simulation of the solid phase of liner implosions which, when applied to simulations exhibiting the ETI and ECI, gave a significant increase in wavelength and amplitude. Full circumference simulations of the MRT instability provided a significant improvement on previous randomly initialised results and approached agreement with experiment.

  17. Expansion of a plasma across a transverse magnetic field in a negative hydrogen ion source for fusion

    Science.gov (United States)

    Fantz, Ursel; Schiesko, Loic; Wünderlich, Dirk

    2012-10-01

    Negative ion sources are a key component of the neutral beam injection systems for the international fusion experiment ITER. To achieve the required ion current of 40 A at a tolerable amount of co-extracted electrons (electron to ion ratio below one) the source is separated into a plasma generation region and an expansion chamber equipped with a magnetic filter field (up to 10 mT). The field is needed for: (1) cooling the electrons down and thus minimize the H^- destruction by collisions, (2) to reduce the co-extracted electron current, and (3) to enhance the extraction probability for the surface produced negative ions. The area of the ITER source will be approximately 1m width and 2 m height, the IPP prototype source is a 1/8-size source. The recently installed flexible magnetic filter frame allows for systematic filter field studies (strength, position, polarity). Two Langmuir probes have been used to measure the plasma parameters simultaneously in axial direction. The profiles in the upper and lower part of the expansion chamber show beside the expected electron temperature and density decrease a drop in the plasma potential and a drift depending on the polarity, which vanishes when removing the filter field. The data interpretation is supported by modeling activities.

  18. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.

    1991-08-01

    This report contains three documents describing the progress made by the University of Illinois electromagnetic railgun program sponsored by the Office of Fusion Energy of the United States Department of Energy during the period from July 16, 1990 to August 16, 1991. The first document contains a brief summary of the tasks initiated, continued, or completed, the status of major tasks, and the research effort distribution, estimated and actual, during the period. The second document contains a description of the work performed on time resolved laser interferometric density measurement of the railgun plasma-arc armature. The third document is an account of research on the spectroscopic measurement of the electron density and temperature of the railgun plasma arc.

  19. Ultrasound/Magnetic Resonance Image Fusion Guided Lumbosacral Plexus Block – A Clinical Study

    DEFF Research Database (Denmark)

    Strid, JM; Pedersen, Erik Morre; Søballe, Kjeld;

    2014-01-01

    In perspective will the US/MR image fusion guided SSPS block provide a safe and effective alternative to traditional anaesthesia and minimise the perioperative need for opioids in fragile hip surgery patients. 1Bendtsen T, Soeballe K, Petersen E, et al. E-letter: Ultrasound guided single injection lumbosacral......Background and aims Ultrasound (US) guided lumbosacral plexus block (Supra Sacral Parallel Shift [SSPS]) offers an alternative to general anaesthesia and perioperative analgesia for hip surgery.1 The complex anatomy of the lumbosacral region hampers the accuracy of the block, but it may be improved...... apart. The block of the L2-S1 nerves, the plasma lidocaine, and the anatomical distribution of lidocaine will be assessed with neurological mapping, pharmacokinetic assays, and MR visualisation and compared. We are awaiting the final ethical approval of the study. Results On going study. Conclusions...

  20. Association Euratom - Risoe National Laboratory annual progress report 1995

    Energy Technology Data Exchange (ETDEWEB)

    Lynov, J.P.; Singh, B.N. [eds.

    1996-05-01

    The programme of the Research Unit of the Fusion Association Euratom - Risoe National Laboratory covers work in fusion plasma physics and in fusion technology. The fusion plasma physics group has activities within studies of nonlinear dynamical processes in magnetized plasmas, and development of pellet injectors for fusion experiments. The activities in technology cover investigations of radiation damage of fusion reactor materials. These activities contribute to the Next Step and the Long-term Technology programme. A summary is presented of the results obtained in the Research Unit during 1995. (au) 5 tabs., 32 ills., 33 refs.

  1. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor fueling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.; Zhang, J.

    1992-01-01

    Three separate papers are included which report research progress during this period: (1) A new railgun configuration with perforated sidewalls, (2) development of a fuseless small-bore railgun for injection of high-speed hydrogen pellets into magnetically confined plasmas, and (3) controls and diagnostics on a fuseless railgun for solid hydrogen pellet injection.

  2. Magnetic fusion energy materials technology program, annual progress report for period ending June 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Scott, J.L. (comp.)

    1976-09-01

    Activities in research programs are reported on materials for use in thermonuclear reactor development. Information and data are included on radiation effects on stainless steel 316, nickel-base alloys, molybdenum-base alloys, vanadium alloys, and SAP. Results of compatibility studies involving iron-base alloys and lithium are also included along with research results on magnet development. (JRD)

  3. Fusion engineering device design description

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, C.A.; Steiner, D.; Smith, G.E.

    1981-12-01

    The US Magnetic Fusion Engineering Act of 1980 calls for the operation of a Fusion Engineering Device (FED) by 1990. It is the intent of the Act that the FED, in combination with other testing facilities, will establish the engineering feasibility of magnetic fusion energy. During 1981, the Fusion Engineering Design Center (FEDC), under the guidance of a Technical Management Board (TMB), developed a baseline design for the FED. This design is summarized herein.

  4. Fusion Engineering Device design description

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, C.A.; Steiner, D.; Smith, G.E.

    1981-12-01

    The US Magnetic Fusion Engineering Act of 1980 calls for the operation of a Fusion Engineering Device (FED) by 1990. It is the intent of the Act that the FED, in combination with other testing facilities, will establish the engineering feasibility of magnetic fusion energy. During 1981, the Fusion Engineering Design Center (FEDC), under the guidance of a Technical Management Board (TMB), developed a baseline design for the FED. This design is summarized herein.

  5. A diamond detector for inertial confinement fusion X-ray bang-time measurements at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    MacPhee, A G; Brown, C; Burns, S; Celeste, J; Glenzer, S H; Hey, D; Jones, O S; Landen, O; Mackinnon, A J; Meezan, N; Parker, J; Edgell, D; Glebov, V Y; Kilkenny, J; Kimbrough, J

    2010-11-09

    An instrument has been developed to measure X-ray bang-time for inertial confinement fusion capsules; the time interval between the start of the laser pulse and peak X-ray emission from the fuel core. The instrument comprises chemical vapor deposited polycrystalline diamond photoconductive X-ray detectors with highly ordered pyrolytic graphite X-ray monochromator crystals at the input. Capsule bang-time can be measured in the presence of relatively high thermal and hard X-ray background components due to the selective band pass of the crystals combined with direct and indirect X-ray shielding of the detector elements. A five channel system is being commissioned at the National Ignition Facility at Lawrence Livermore National Laboratory for implosion optimization measurements as part of the National Ignition Campaign. Characteristics of the instrument have been measured demonstrating that X-ray bang-time can be measured with {+-} 30ps precision, characterizing the soft X-ray drive to +/- 1eV or 1.5%.

  6. [Application of positron-emission tomography-magnetic resonance imaging fusion in biopsy and resection of gliomas].

    Science.gov (United States)

    Guo, Xu; Guo, Yi; Cheng, Xin; Zhong, Ding-rong; Wang, Yu; Wang, Ren-zhi; Ma, Wen-bin

    2013-01-01

    To assess the value and feasibility of positron-emission tomography-magnetic resonance imaging (PET-MRI) fusion technology in delineating tumor boundaries and positioning biopsy targets of gliomas so as to facilitate the diagnosis and treatment of gliomas. A total of 18 patients with a preoperative diagnosis of gliomas discharged from our hospital from January 2010 to April 2011 were recruited. All of them underwent the preoperative examinations of MRI, fluorodeoxyglucose (FDG) PET and fluoroethyl-choline (FECH) PET. The digital image data were transferred into Brain LAB planning software and three types of images automatically fused. The tumor contours were drawn on the basis of each image modality separately. The extent of tumor resection or biopsy target was determined on the integrated information including tumor contours on PET and MRI images and intraoperative observation of tumor texture. On PET scans, the average standard uptake value (SUV) of glioblastomas was higher than that of grade II-III gliomas. With regard to the patients with both biopsy and tumor resection, the pathological diagnosis of the specimen obtained from the PET-guided biopsy was consistent with that of subsequently resected tissue. All 11 patients undergoing tumor resection were classified according to relationship between the image-based tumor contour and actual extent of resection. Six of them benefited from contour delineated by FDG PET images and 3 of them benefited from FECH PET. The combined contribution ratio of both PET methods was 9/11. PET-MRI fusion technology may accurately delineate tumor boundary and sensitively target the region of high proliferation or metabolism. A more radical resection and more accurate histological diagnosis can be thus achieved and yield a probably better prognosis of gliomas.

  7. High-resolution measurements of the DT neutron spectrum using new CD foils in the Magnetic Recoil neutron Spectrometer (MRS) on the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Gatu Johnson, M., E-mail: gatu@psfc.mit.edu; Frenje, J. A.; Li, C. K.; Petrasso, R. D.; Séguin, F. H. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Bionta, R. M.; Casey, D. T.; Eckart, M. J.; Grim, G. P.; Hartouni, E. P.; Hatarik, R.; Sayre, D. B.; Skulina, K.; Yeamans, C. B. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Farrell, M. P.; Hoppe, M.; Kilkenny, J. D.; Reynolds, H. G.; Schoff, M. E. [General Atomics, San Diego, California 92186 (United States)

    2016-11-15

    The Magnetic Recoil neutron Spectrometer (MRS) on the National Ignition Facility measures the DT neutron spectrum from cryogenically layered inertial confinement fusion implosions. Yield, areal density, apparent ion temperature, and directional fluid flow are inferred from the MRS data. This paper describes recent advances in MRS measurements of the primary peak using new, thinner, reduced-area deuterated plastic (CD) conversion foils. The new foils allow operation of MRS at yields 2 orders of magnitude higher than previously possible, at a resolution down to ∼200 keV FWHM.

  8. Concepts of magnetic filter fields in powerful negative ion sources for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, W., E-mail: kraus@ipp.mpg.de; Fantz, U.; Heinemann, B.; Wünderlich, D. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2016-02-15

    The performance of large negative ion sources used in neutral beam injection systems is in long pulses mainly determined by the increase of the currents of co-extracted electrons. This is in particular a problem in deuterium and limits the ion currents which are for long pulses below the requirements for the ITER source. In the source of the ELISE test facility, the magnetic field in front of the first grid, which is essential to reduce the electron current, is generated by a current of several kA flowing through the plasma facing grid. Weakening of this field by the addition of permanent magnets placed close to the lateral walls has led to a reduction of the electron current by a factor three without loss of ion current when source was operated in volume production. If this effect can be validated for the cesiated source, it would be a large step towards achieving the ITER parameter in long pulses.

  9. Transient Behaviour of Superconducting Magnet Systems of Fusion Reactor ITER during Safety Discharge

    Directory of Open Access Journals (Sweden)

    A. M. Miri

    2008-01-01

    Full Text Available To investigate the transient behaviour of the toroidal and poloidal field coils magnet systems of the International Thermonuclear Experimental Reactor during safety discharge, network models with lumped elements are established. Frequency-dependant values of the network elements, that is, inductances and resistances are calculated with the finite element method. That way, overvoltages can be determined. According to these overvoltages, the insulation coordination of coils has to be selected.

  10. Fully Automated Prostate Magnetic Resonance Imaging and Transrectal Ultrasound Fusion via a Probabilistic Registration Metric

    OpenAIRE

    Sparks, Rachel; Bloch, B. Nicolas; Feleppa, Ernest; Barratt, Dean; Madabhushi, Anant

    2013-01-01

    In this work, we present a novel, automated, registration method to fuse magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) images of the prostate. Our methodology consists of: (1) delineating the prostate on MRI, (2) building a probabilistic model of prostate location on TRUS, and (3) aligning the MRI prostate segmentation to the TRUS probabilistic model. TRUS-guided needle biopsy is the current gold standard for prostate cancer (CaP) diagnosis. Up to 40% of CaP lesions appea...

  11. Current-carrying element based on second-generation high-temperature superconductor for the magnet system of a fusion neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, M. S., E-mail: mihailnovikov@yandex.ru; Ivanov, D. P., E-mail: Ivanov-DP@nrcki.ru, E-mail: denis.ivanov30@mail.ru; Novikov, S. I., E-mail: novikov-si@nrcki.ru; Shuvaev, S. A., E-mail: ser-shuvaev@yandex.ru, E-mail: sergey.shuvaev@phystech.edu [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    Application of current-carrying elements (CCEs) made of second-generation high-temperature superconductor (2G HTS) in magnet systems of a fusion neutron source (FNS) and other fusion devices will allow their magnetic field and thermodynamic stability to be increased substantially in comparison with those of low-temperature superconductor (LTS) magnets. For a toroidal magnet of the FNS, a design of a helical (partially transposed) CCE made of 2G HTS is under development with forced-flow cooling by helium gas, a current of 20–30 kA, an operating temperature of 10–20 K, and a magnetic field on the winding of 12–15 T (prospectively ∼20 T). Short-sized samples of the helical flexible heavy-current CCE are being fabricated and investigated; a pilot-line unit for production of long-sized CCE pieces is under construction. The applied fabrication technique allows the CCE to be produced which combines a high operating current, thermal and mechanical stability, manufacturability, and low losses in the alternating modes. The possibility of fabricating the CCE with the outer dimensions and values of the operating parameter required for the FNS (and with a significant margin) using already available serial 2G HTS tapes is substantiated. The maximum field of toroidal magnets with CCEs made of 2G HTS will be limited only by mechanical properties of the magnet’s casing and structure, while the thermal stability will be approximately two orders of magnitude higher than that of toroidal magnets with LTS-based CCEs. The helical CCE made of 2G HTS is very promising for fusion and hybrid electric power plants, and its design and technologies of production, as well as the prototype coils made of it for the FNS and other tokamaks, are worth developing now.

  12. A computer tool for the fusion and visualization of thermal and magnetic resonance images.

    Science.gov (United States)

    Bichinho, Gerson Linck; Gariba, Munir Antonio; Sanches, Ionildo José; Gamba, Humberto Remigio; Cruz, Felipe Pardal Franco; Nohama, Percy

    2009-10-01

    The measurement of temperature variation along the surface of the body, provided by digital infrared thermal imaging (DITI), is becoming a valuable auxiliary tool for the early detection of many diseases in medicine. However, DITI is essentially a 2-D technique and its image does not provide useful anatomical information associated with it. However, multimodal image registration and fusion may overcome this difficulty and provide additional information for diagnosis purposes. In this paper, a new method of registering and merging 2-D DITI and 3-D MRI is presented. Registration of the images acquired from the two modalities is necessary as they are acquired with different image systems. Firstly, the body volume of interest is scanned by a MRI system and a set of 2-D DITI of it, at orthogonal angles, is acquired. Next, it is necessary to register these two different sets of images. This is done by creating 2-D MRI projections from the reconstructed 3-D MRI volume and registering it with the DITI. Once registered, the DITI is then projected over the 3-D MRI. The program developed to assess the proposed method to combine MRI and DITI resulted in a new tool for fusing two different image modalities, and it can help medical doctors.

  13. Boundary and PMI Diagnostics for the DIII-D National Fusion Facility

    Science.gov (United States)

    Thomas, D. M.; Bray, B. D.; Chrobak, C.; Leonard, A. W.; Allen, S. L.; Lasnier, C. J.; McLean, A. G.; Briesemeister, A. R.; Boedo, J. A.; Elder, D.; Watkins, J. G.

    2014-10-01

    The Boundary and Plasma Materials Interaction Center is planning an improved set of boundary and divertor diagnostics for DIII-D in order to develop and validate robust heat flux solutions for future fusion devices on a timescale relevant to the design of FNSF. We intend to develop and test advanced divertor configurations on DIII-D using high performance plasma scenarios that are compatible with advanced tokamak operations in FNSF as well as providing a comprehensive testbed for modeling. Simultaneously, candidate PFC material solutions can be easily tested in these scenarios. Additional diagnostic capability is vital to help understand and validate these solutions. We will describe a number of desired measurements and our plans for deployment. These include better accounting of divertor radiation, including species identification and spatial distribution, divertor/SOL main ion temperature and neutral pressure, fuller 2D Te /ne imaging, and toroidally separated 3D heat flux measurements. Work supported by the US Department of Energy under DE-FC02-04ER54698, DE-AC52-07NA27344, DE-AC05-00OR22725, DE-FG02-07EAR54917, and DE-AC04-94AL85000.

  14. Prospects for a dominantly microwave-diagnosed magnetically confined fusion reactor

    Science.gov (United States)

    Volpe, F. A.

    2017-01-01

    Compared to present experiments, tokamak and stellarator reactors will be subject to higher heat loads, sputtering, erosion and subsequent coating, tritium retention, higher neutron fluxes, and a number of radiation effects. Additionally, neutral beam penetration in tokamak reactors will only be limited to the plasma edge. As a result, several optical, beam-based and magnetic diagnostics of today's plasmas might not be applicable to tomorrow's reactors, but the present discussion suggests that reactors could largely rely on microwave diagnostics, including techniques based on mode conversions and Collective Thomson Scattering.

  15. Inertial Confinement Fusion alpha-heating signatures in prompt gamma-ray measurements at the National Ignition Facility

    Science.gov (United States)

    Church, Jennifer; Herrmann, Hans; Cerjan, Charlie; Sayre, Daniel; Carpenter, Arthur; Liebman, Judy; Stoeffl, Wolfgang; Kim, Yongho

    2015-11-01

    Prompt gamma-rays measured at the National Ignition Facility (NIF) with the Gamma-ray Reaction History detector (GRH) supply vital diagnostic information, such as the peak burn time, burn width, and total neutron yield, from prompt DT-fusion gamma-ray emission during high convergence implosion experiments. Additionally, the stagnated cold shell density distribution may be inferred from the time-integrated, calibrated 12C (n,n' γ) signal, thus providing estimates of remaining ablator carbon areal density. Furthermore, simulations suggest that alpha heating signatures might be accessible using more highly resolved temporal gamma-ray emission. Correlation of these signatures with time-dependent neutron emission will constrain the implosion dynamics immediately prior to thermonuclear burn. Measurement of these gamma-ray signatures will be discussed along with updates on our work toward inferred total DT yield and 12C areal density. This work performed under the auspices of the U.S. Dept. of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07-NA27344, LLNL-ABS-670282.

  16. Fusion of Inertial/Magnetic Sensor Measurements and Map Information for Pedestrian Tracking.

    Science.gov (United States)

    Bao, Shu-Di; Meng, Xiao-Li; Xiao, Wendong; Zhang, Zhi-Qiang

    2017-02-10

    The wearable inertial/magnetic sensor based human motion analysis plays an important role in many biomedical applications, such as physical therapy, gait analysis and rehabilitation. One of the main challenges for the lower body bio-motion analysis is how to reliably provide position estimations of human subject during walking. In this paper, we propose a particle filter based human position estimation method using a foot-mounted inertial and magnetic sensor module, which not only uses the traditional zero velocity update (ZUPT), but also applies map information to further correct the acceleration double integration drift and thus improve estimation accuracy. In the proposed method, a simple stance phase detector is designed to identify the stance phase of a gait cycle based on gyroscope measurements. For the non-stance phase during a gait cycle, an acceleration control variable derived from ZUPT information is introduced in the process model, while vector map information is taken as binary pseudo-measurements to further enhance position estimation accuracy and reduce uncertainty of walking trajectories. A particle filter is then designed to fuse ZUPT information and binary pseudo-measurements together. The proposed human position estimation method has been evaluated with closed-loop walking experiments in indoor and outdoor environments. Results of comparison study have illustrated the effectiveness of the proposed method for application scenarios with useful map information.

  17. Fusion of Inertial/Magnetic Sensor Measurements and Map Information for Pedestrian Tracking

    Science.gov (United States)

    Bao, Shu-Di; Meng, Xiao-Li; Xiao, Wendong; Zhang, Zhi-Qiang

    2017-01-01

    The wearable inertial/magnetic sensor based human motion analysis plays an important role in many biomedical applications, such as physical therapy, gait analysis and rehabilitation. One of the main challenges for the lower body bio-motion analysis is how to reliably provide position estimations of human subject during walking. In this paper, we propose a particle filter based human position estimation method using a foot-mounted inertial and magnetic sensor module, which not only uses the traditional zero velocity update (ZUPT), but also applies map information to further correct the acceleration double integration drift and thus improve estimation accuracy. In the proposed method, a simple stance phase detector is designed to identify the stance phase of a gait cycle based on gyroscope measurements. For the non-stance phase during a gait cycle, an acceleration control variable derived from ZUPT information is introduced in the process model, while vector map information is taken as binary pseudo-measurements to further enhance position estimation accuracy and reduce uncertainty of walking trajectories. A particle filter is then designed to fuse ZUPT information and binary pseudo-measurements together. The proposed human position estimation method has been evaluated with closed-loop walking experiments in indoor and outdoor environments. Results of comparison study have illustrated the effectiveness of the proposed method for application scenarios with useful map information. PMID:28208591

  18. Fusion research principles

    CERN Document Server

    Dolan, Thomas James

    2013-01-01

    Fusion Research, Volume I: Principles provides a general description of the methods and problems of fusion research. The book contains three main parts: Principles, Experiments, and Technology. The Principles part describes the conditions necessary for a fusion reaction, as well as the fundamentals of plasma confinement, heating, and diagnostics. The Experiments part details about forty plasma confinement schemes and experiments. The last part explores various engineering problems associated with reactor design, vacuum and magnet systems, materials, plasma purity, fueling, blankets, neutronics

  19. Experimental results of a sheet-beam, high power, FEL amplifier with application to magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, S.; Destler, W.W.; Granatstein, V.L. [Univ. of Maryland, College Park, MD (United States)] [and others

    1995-12-31

    The experimental study of sheet-beam FELs as candidate millimeter-wave sources for heating magnetic fusion plasmas has achieved a major milestone. In a proof-of-principle, pulsed experiment, saturated FEL amplifier operation was achieved with 250 kW of output power at 86 GHz. Input microwave power was 1 kW, beam voltage was 450 kV and beam current was 17 A. The planar wiggler had a peak value of 3.8 kG, a period of 0.96 cm and was 71 cm long. The linear gain of 30 dB, saturated gain of 24 dB and saturated efficiency of 3% all are in good agreement with theoretical prediction. Follow-on work would include development of a thermionic sheet-beam electron-gun compatible with CW FEL operation, adding a section of tapered wiggler to increase the output power to levels in excess of 1 megawatt, and increasing the FEL frequency.

  20. Directed Energy HPM, PP, & PPS Efforts: Magnetized Target Fusion - Field Reversed Configuration

    Science.gov (United States)

    2006-08-04

    process, with the aid of MathCAD to perform the calculations, the self-geometric mean distance of the ensemble of return-conductor plates from itself...release to foreign nationals within the United States , without first obtaining approval or license from the Department of State for items controlled by the...and only a few minor corrections to the drawings, all drawings were sent out to local machine shops for bids and parts fabrication. Drawings for a

  1. Magnetic quadrupoles lens for hot spot proton imaging in inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Teng, J. [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Gu, Y.Q., E-mail: yqgu@caep.cn [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Center for Applied Physics and Technology, HEDPS, Peking University, Beijing 100871 (China); Chen, J.; Zhu, B.; Zhang, B.; Zhang, T.K.; Tan, F.; Hong, W.; Zhang, B.H. [Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Wang, X.Q. [Academy of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China)

    2016-08-01

    Imaging of DD-produced protons from an implosion hot spot region by miniature permanent magnetic quadrupole (PMQ) lens is proposed. Corresponding object-image relation is deduced and an adjust method for this imaging system is discussed. Ideal point-to-point imaging demands a monoenergetic proton source; nevertheless, we proved that the blur of image induced by proton energy spread is a second order effect therefore controllable. A proton imaging system based on miniature PMQ lens is designed for 2.8 MeV DD-protons and the adjust method in case of proton energy shift is proposed. The spatial resolution of this system is better than 10 μm when proton yield is above 10{sup 9} and the spectra width is within 10%.

  2. Thermonuclear fusion in dense stars: Electron screening, conductive cooling, and magnetic field effects

    CERN Document Server

    Potekhin, A Y

    2012-01-01

    We study the plasma correlation effects on nonresonant thermonuclear reactions of carbon and oxygen in the interiors of white dwarfs and liquid envelopes of neutron stars. We examine the effects of electron screening on thermodynamic enhancement of thermonuclear reactions in dense plasmas beyond the linear mixing rule. Using these improved enhancement factors, we calculate carbon and oxygen ignition curves in white dwarfs and neutron stars. The energy balance and ignition conditions in neutron star envelopes are evaluated, taking their detailed thermal structure into account. The result is compared to the simplified "one-zone model," which is routinely used in the literature. We also consider the effect of strong magnetic fields on the ignition curves in the ocean of magnetars.

  3. Controlled Nuclear Fusion.

    Science.gov (United States)

    Glasstone, Samuel

    This publication is one of a series of information booklets for the general public published by The United States Atomic Energy Commission. Among the topics discussed are: Importance of Fusion Energy; Conditions for Nuclear Fusion; Thermonuclear Reactions in Plasmas; Plasma Confinement by Magnetic Fields; Experiments With Plasmas; High-Temperature…

  4. Controlled thermonuclear fusion

    CERN Document Server

    Bobin, Jean Louis

    2014-01-01

    The book is a presentation of the basic principles and main achievements in the field of nuclear fusion. It encompasses both magnetic and inertial confinements plus a few exotic mechanisms for nuclear fusion. The state-of-the-art regarding thermonuclear reactions, hot plasmas, tokamaks, laser-driven compression and future reactors is given.

  5. A Trusted National Fusion Center Network: Are Baseline Capabilities and Accreditation Needed?

    Science.gov (United States)

    2010-09-01

    proximity, culture, and/or characteristics of the area of responsibility, and include indicators of those gangs such as colors, graffiti, tattoos ...important is the need for the establishment of a level of trust and credibility in the eyes of the public, elected officials, and the national, state, local...programs by establishing credible standards applied in a peer review accreditation process. (EMAP, 2009) The goals for EMAP include expanding the

  6. Burn Control of Magnetically Confined Fusion Plasma 2. Burn Control in Tokamak Fusion Reactors 2.3 Burn Control in ITER

    Science.gov (United States)

    Fujisawa, Noboru

    The issue of burn control in FDR-ITER, the design of which was completed in 1998, is introduced, Controllability was studied based on the ID transport code, PRETOR, during the burn phase with self-ignition, as well as during start-up and shut-down. The results of the present study have helped us to identify the importance of controlling the fuel supply, impurity injection, and heating power to maintain fusion power and power to the divertor.

  7. On the physical conditions for arising a controlled fusion chain reaction supported by neutrons in fusion facilities with magnetic plasma confinement

    Directory of Open Access Journals (Sweden)

    A.N. Shmelyov

    2015-11-01

    The fusion neutron source is considered to be the “richest”: neutron generation is accompanied by relatively small-scale processes. The thermonuclear facility with low neutron absorption blanket under consideration here could create a high density neutron flux in the blanket. It can be concluded from the above that such thermonuclear facilities could be used for fast transmutation of long-lived fission products with low neutron absorption cross-section, and perhaps even without their preliminary isotopic separation.

  8. Value of Targeted Prostate Biopsy Using Magnetic Resonance–Ultrasound Fusion in Men with Prior Negative Biopsy and Elevated Prostate-specific Antigen

    Science.gov (United States)

    Sonn, Geoffrey A.; Chang, Edward; Natarajan, Shyam; Margolis, Daniel J.; Macairan, Malu; Lieu, Patricia; Huang, Jiaoti; Dorey, Frederick J.; Reiter, Robert E.; Marks, Leonard S.

    2013-01-01

    Background Conventional biopsy fails to detect the presence of some prostate cancers (PCas). Men with a prior negative biopsy but persistently elevated prostate-specific antigen (PSA) pose a diagnostic dilemma, as some harbor elusive cancer. Objective To determine whether use of magnetic resonance–ultrasound (MR-US) fusion biopsy results in improved detection of PCa compared to repeat conventional biopsy. Design, setting, and participants In a consecutive-case series, 105 subjects with prior negative biopsy and elevated PSA values underwent multiparametric magnetic resonance imaging (MRI) and fusion biopsy in an outpatient setting. Intervention Suspicious areas on multiparametric MRI were delineated and graded by a radiologist; MR–US fusion biopsy was performed by a urologist using the Artemis device; targeted and systematic biopsies were obtained regardless of MRI result. Outcome measurements and statistical analysis Detection rates of all PCa and clinically significant PCa (Gleason ≥3 + 4 or Gleason 6 with maximal cancer core length ≥4 mm) were determined. The yield of targeted biopsy was compared to systematic biopsy. The ability of an MRI grading system to predict clinically significant cancer was investigated. Stepwise multivariate logistic regression analysis was performed to determine predictors of significant cancer on biopsy. Results and limitations Fusion biopsy revealed PCa in 36 of 105 men (34%; 95% confidence interval [CI], 25–45). Seventy-two percent of men with PCa had clinically significant disease; 21 of 23 men (91%) with PCa on targeted biopsy had significant cancer compared to 15 of 28 (54%) with systematic biopsy. Degree of suspicion on MRI was the most powerful predictor of significant cancer on multivariate analysis. Twelve of 14 (86%) subjects with a highly suspicious MRI target were diagnosed with clinically significant cancer. Conclusions MR-US fusion biopsy provides improved detection of PCa in men with prior negative biopsies

  9. Conceptual studies of toroidal field magnets for the tokamak (fusion) experimental power reactor. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1976-11-01

    This report presents the results of ''Conceptual Studies of Toroidal Field Magnets for the Tokamak Experimental Power Reactor'' performed for the Energy Research and Development Administration, Oak Ridge Operations. Two conceptual coil designs are developed. One design approach to produce a specified 8 Tesla maximum field uses a novel NbTi superconductor design cooled by pool-boiling liquid helium. For a highest practicable field design, a unique NbSn/sub 3/ conductor is used with forced-flow, single-phase liquid helium cooling to achieve a 12 Tesla peak field. Fabrication requirements are also developed for these approximately 7 meter horizontal bore by 11 meter vertical bore coils. Cryostat design approaches are analyzed and a hybrid cryostat approach selected. Structural analyses are performed for approaches to support in-plane and out-of-plane loads and a structural approach selected. In addition to the conceptual design studies, cost estimates and schedules are prepared for each of the design approaches, major uncertainties and recommendations for research and development identified, and test coil size for demonstration recommended.

  10. Adiabatic Quasi-Spherical Compressions Driven by Magnetic Pressure for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    NASH,THOMAS J.

    2000-11-01

    The magnetic implosion of a high-Z quasi-spherical shell filled with DT fuel by the 20-MA Z accelerator can heat the fuel to near-ignition temperature. The attainable implosion velocity on Z, 13-cm/{micro}s, is fast enough that thermal losses from the fuel to the shell are small. The high-Z shell traps radiation losses from the fuel, and the fuel reaches a high enough density to reabsorb the trapped radiation. The implosion is then nearly adiabatic. In this case the temperature of the fuel increases as the square of the convergence. The initial temperature of the fuel is set by the heating of an ion acoustic wave to be about 200-eV after a convergence of 4. To reach the ignition temperature of 5-keV an additional convergence of 5 is required. The implosion dynamics of the quasi-spherical implosion is modeled with the 2-D radiation hydrodynamic code LASNEX. LASNEX shows an 8-mm diameter quasi-spherical tungsten shell on Z driving 6-atmospheres of DT fuel nearly to ignition at 3.5-keV with a convergence of 20. The convergence is limited by mass flow along the surface of the quasi-spherical shell. With a convergence of 20 the final spot size is 400-{micro}m in diameter.

  11. Adiabatic Quasi-Spherical Compressions Driven by Magnetic Pressure for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    NASH,THOMAS J.

    2000-11-01

    The magnetic implosion of a high-Z quasi-spherical shell filled with DT fuel by the 20-MA Z accelerator can heat the fuel to near-ignition temperature. The attainable implosion velocity on Z, 13-cm/{micro}s, is fast enough that thermal losses from the fuel to the shell are small. The high-Z shell traps radiation losses from the fuel, and the fuel reaches a high enough density to reabsorb the trapped radiation. The implosion is then nearly adiabatic. In this case the temperature of the fuel increases as the square of the convergence. The initial temperature of the fuel is set by the heating of an ion acoustic wave to be about 200-eV after a convergence of 4. To reach the ignition temperature of 5-keV an additional convergence of 5 is required. The implosion dynamics of the quasi-spherical implosion is modeled with the 2-D radiation hydrodynamic code LASNEX. LASNEX shows an 8-mm diameter quasi-spherical tungsten shell on Z driving 6-atmospheres of DT fuel nearly to ignition at 3.5-keV with a convergence of 20. The convergence is limited by mass flow along the surface of the quasi-spherical shell. With a convergence of 20 the final spot size is 400-{micro}m in diameter.

  12. Sensor fusion of electron paramagnetic resonance and magnetorelaxometry data for quantitative magnetic nanoparticle imaging

    Science.gov (United States)

    Coene, A.; Leliaert, J.; Crevecoeur, G.; Dupré, L.

    2017-03-01

    Magnetorelaxometry (MRX) imaging and electron paramagnetic resonance (EPR) are two non-invasive techniques capable of recovering the magnetic nanoparticle (MNP) distribution. Both techniques solve an ill-posed inverse problem in order to find the spatial MNP distribution. A lot of research has been done on increasing the stability of these inverse problems with the main objective to improve the quality of MNP imaging. In this paper a proof of concept is presented in which the sensor data of both techniques is fused into EPR–MRX, with the intention to stabilize the inverse problem. First, both techniques are compared by reconstructing several phantoms with different sizes for various noise levels and calculating stability, sensitivity and reconstruction quality parameters for these cases. This study reveals that both techniques are sensitive to different information from the MNP distributions and generate complementary measurement data. As such, their merging might stabilize the inverse problem. In a next step we investigated how both techniques need to be combined to reduce their respective drawbacks, such as a high number of required measurements and reduced stability, and to improve MNP reconstructions. We were able to stabilize both techniques, increase reconstruction quality by an average of 5% and reduce measurement times by 88%. These improvements could make EPR–MRX a valuable and accurate technique in a clinical environment.

  13. Gyrotrons for magnetic fusion applications at 110 GHz and 170 GHz

    Directory of Open Access Journals (Sweden)

    Cahalan P.

    2012-09-01

    Full Text Available Two megawatt-class gyrotrons at frequencies of 110 GHz and 170 GHz have recently been fabricated at CPI. The 110 GHz gyrotron is designed to produce 1.2 MW of output power for 10-second pulses, and will be used for electron cyclotron heating and current drive on the DIII-D tokamak at General Atomics. This gyrotron has completed factory testing and has been delivered to General Atomics for installation and additional testing. The 170 GHz gyrotron, though specified as a 500 kW CW system, has been designed with the goal of generating up to 1 MW CW. Oak Ridge National Laboratory will use this gyrotron in ITER ECH transmission line testing. This gyrotron has been fabricated and is awaiting factory testing, Design features of each gyrotron are described, and test data for the 110 GHz gyrotron are presented.

  14. Comparison of the Recently proposed Super Marx Generator Approach to Thermonuclear Ignition with the DT Laser Fusion-Fission Hybrid Concept (LIFE) by the Lawrence Livermore National Laboratory.

    Science.gov (United States)

    Winterberg, Friedwardt

    2009-05-01

    The recently proposed Super Marx pure deuterium micro-detonation ignition concept [1] is compared to the Lawrence Livermore National Ignition Facility (NIF) laser DT fusion-fission hybrid concept (LIFE) [2]. A typical example of the LIFE concept is a fusion gain 30, and a fission gain of 10, making up for a total gain of 300, with about 10 times more energy released into fission as compared to fusion. This means a substantial release of fission products, as in fusion-less pure fission reactors. In the Super Marx approach for the ignition of a pure deuterium micro-detonation gains of the same magnitude can in theory be reached. If the theoretical prediction can be supported by more elaborate calculations, the Super Marx approach is likely to make lasers obsolete as a means for the ignition of thermonuclear micro-explosions. [1] ``Ignition of a Deuterium Micro-Detonation with a Gigavolt Super Marx Generator,'' Winterberg, F., Journal of Fusion Energy, Springer, 2008. http://www.springerlink.com/content/r2j046177j331241/fulltext.pdf. [2] ``LIFE: Clean Energy from Nuclear Waste,'' https://lasers.llnl.gov/missions/energy&_slash;for&_slash;the&_slash;future/life/

  15. Bayesian Analysis of Inertial Confinement Fusion Experiments at the National Ignition Facility

    CERN Document Server

    Gaffney, J A; Sonnad, V; Libby, S B

    2012-01-01

    We develop a Bayesian inference method that allows the efficient determination of several interesting parameters from complicated high-energy-density experiments performed on the National Ignition Facility (NIF). The model is based on an exploration of phase space using the hydrodynamic code HYDRA. A linear model is used to describe the effect of nuisance parameters on the analysis, allowing an analytic likelihood to be derived that can be determined from a small number of HYDRA runs and then used in existing advanced statistical analysis methods. This approach is applied to a recent experiment in order to determine the carbon opacity and X-ray drive; it is found that the inclusion of prior expert knowledge and fluctuations in capsule dimensions and chemical composition significantly improve the agreement between experiment and theoretical opacity calculations. A parameterisation of HYDRA results is used to test the application of both Markov chain Monte Carlo (MCMC) and genetic algorithm (GA) techniques to e...

  16. Fabrication of Meter-Scale Laser Resistant Mirrors for the National Ignition Facility, a Fusion Laser

    Energy Technology Data Exchange (ETDEWEB)

    Stolz, C J; Weinzapfel, C L; Rigatti, A L; Oliver, J B; Taniguchi, J; Bevis, R P; Rajasansi, J S

    2003-07-07

    Large-aperture laser-resistant mirrors are required for the construction of the National Ignition Facility, a 1.8 MJ laser. In order to fabricate the 1408 mirrors, a development program was started in 1994 to improve coating quality, manufacturing rate, and lower unit cost. New technologies and metrology tools were scaled to meter size for facilitization in 1999 at Spectra-Physics and the Laboratory of Laser Energetics at the University of Rochester. Pilot production, to fabricate 5-10% of each component, commenced in 2001 and full production rates were achieved in 2002. Coating production will be completed in 2008 with the coating of 460 m{sup 2} of high-damage-threshold precision coatings on 100 tons of BK7 glass with yields exceeding 90%.

  17. Frontiers in fusion research

    CERN Document Server

    Kikuchi, Mitsuru

    2011-01-01

    Frontiers in Fusion Research provides a systematic overview of the latest physical principles of fusion and plasma confinement. It is primarily devoted to the principle of magnetic plasma confinement, that has been systematized through 50 years of fusion research. Frontiers in Fusion Research begins with an introduction to the study of plasma, discussing the astronomical birth of hydrogen energy and the beginnings of human attempts to harness the Sun's energy for use on Earth. It moves on to chapters that cover a variety of topics such as: * charged particle motion, * plasma kinetic theory, *

  18. Theory of hydro-equivalent ignition for inertial fusion and its applications to OMEGA and the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Nora, R.; Betti, R.; Bose, A.; Woo, K. M.; Christopherson, A. R.; Meyerhofer, D. D. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Fusion Science Center, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Physics and/or Mechanical Engineering, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Anderson, K. S.; Shvydky, A.; Marozas, J. A.; Collins, T. J. B.; Radha, P. B.; Hu, S. X.; Epstein, R.; Marshall, F. J.; Sangster, T. C. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); McCrory, R. L. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Physics and/or Mechanical Engineering, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)

    2014-05-15

    The theory of ignition for inertial confinement fusion capsules [R. Betti et al., Phys. Plasmas 17, 058102 (2010)] is used to assess the performance requirements for cryogenic implosion experiments on the Omega Laser Facility. The theory of hydrodynamic similarity is developed in both one and two dimensions and tested using multimode hydrodynamic simulations with the hydrocode DRACO [P. B. Radha et al., Phys. Plasmas 12, 032702 (2005)] of hydro-equivalent implosions (implosions with the same implosion velocity, adiabat, and laser intensity). The theory is used to scale the performance of direct-drive OMEGA implosions to the National Ignition Facility (NIF) energy scales and determine the requirements for demonstrating hydro-equivalent ignition on OMEGA. Hydro-equivalent ignition on OMEGA is represented by a cryogenic implosion that would scale to ignition on the NIF at 1.8 MJ of laser energy symmetrically illuminating the target. It is found that a reasonable combination of neutron yield and areal density for OMEGA hydro-equivalent ignition is 3 to 6 × 10{sup 13} and ∼0.3 g/cm{sup 2}, respectively, depending on the level of laser imprinting. This performance has not yet been achieved on OMEGA.

  19. Inertial Confinement Fusion R&D and Nuclear Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Goldston

    2011-04-28

    In a few months, or a few years, the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory may achieve fusion gain using 192 powerful lasers to generate x-rays that will compress and heat a small target containing isotopes of hydrogen. This event would mark a major milestone after decades of research on inertial confinement fusion (ICF). It might also mark the beginning of an accelerated global effort to harness fusion energy based on this science and technology. Unlike magnetic confinement fusion (ITER, 2011), in which hot fusion fuel is confined continuously by strong magnetic fields, inertial confinement fusion involves repetitive fusion explosions, taking advantage of some aspects of the science learned from the design and testing of hydrogen bombs. The NIF was built primarily because of the information it would provide on weapons physics, helping the United States to steward its stockpile of nuclear weapons without further underground testing. The U.S. National Academies' National Research Council is now hosting a study to assess the prospects for energy from inertial confinement fusion. While this study has a classified sub-panel on target physics, it has not been charged with examining the potential nuclear proliferation risks associated with ICF R&D. We argue here that this question urgently requires direct and transparent examination, so that means to mitigate risks can be assessed, and the potential residual risks can be balanced against the potential benefits, now being assessed by the NRC. This concern is not new (Holdren, 1978), but its urgency is now higher than ever before.

  20. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  1. Soil magnetic properties in Bulgaria at a national scale-Challenges and benefits

    Science.gov (United States)

    Jordanova, Neli; Jordanova, Diana; Petrov, Petar

    2016-02-01

    Establishing topsoil magnetic database at a national scale provides important information for soil classification, evaluation of soil drainage, indirect estimation of the total soil carbon and initial planning in precision agriculture. The Bulgarian database consists of 511 topsoil samples from the upper 20 cm of natural unpolluted soils. Samples have been characterized by detailed magnetic measurements, including mass-specific magnetic susceptibility, frequency dependent magnetic susceptibility, anhysteretic remanence, isothermal remanence and their ratios, hysteresis parameters and ratios, as well as soil reaction (pH). Histograms of the measured parameters per soil type and for the whole database show specific peculiarities and dependence from various parameters. Statistical factor analysis revealed that 87% from the total variance can be explained by four factors. The main factor is dominated by the contribution from concentration-dependent magnetic parameters, second one reflects the role of fine-grained pedogenic magnetic fraction, the third one is determined by the properties of the parent material, fourth one is governed by the internal structural peculiarities of the magnetic particles. The results from cluster analysis reveal the role of soil type and geology for the observed magnetic characteristics. The results emphasize the major role of geology (parent material) for the magnetic signature of topsoil samples on a national scale using sampling density of 1 sample/200 km2. Spatial interpolation of different magnetic parameters using modelled experimental variograms and kriging algorithm highlight lateral peculiarities in the concentration and grain size of the strongly magnetic iron oxides in the topsoils. Additional geochemical data for selected set of samples and meteorological information reveal the role of climate characteristics (mean annual temperature and precipitation) on the formation and development of the strongly magnetic pedogenic fraction

  2. Comparison of the Recently proposed Super Marx Generator Approach to Thermonuclear Ignition with the DT Laser Fusion-Fission Hybrid Concept by the Lawrence Livermore National Laboratory

    CERN Document Server

    Winterberg, Friedwardt

    2009-01-01

    The recently proposed Super Marx generator pure deuterium micro-detonation ignition concept is compared to the Lawrence Livermore National Ignition Facility (NIF) Laser DT fusion-fission hybrid concept (LiFE) [1]. In a Super Marx generator a large number of ordinary Marx generators charge up a much larger second stage ultra-high voltage Marx generator, from which for the ignition of a pure deuterium micro-explosion an intense GeV ion beam can be extracted. A typical example of the LiFE concept is a fusion gain of 30, and a fission gain of 10, making up for a total gain of 300, with about 10 times more energy released into fission as compared to fusion. This means a substantial release of fission products, as in fusion-less pure fission reactors. In the Super Marx approach for the ignition of a pure deuterium micro-detonation a gain of the same magnitude can in theory be reached [2]. If feasible, the Super Marx generator deuterium ignition approach would make lasers obsolete as a means for the ignition of ther...

  3. Incidence, Predictors, and Postoperative Complications of Blood Transfusion in Thoracic and Lumbar Fusion Surgery: An Analysis of 13,695 Patients from the American College of Surgeons National Surgical Quality Improvement Program Database.

    Science.gov (United States)

    Aoude, Ahmed; Nooh, Anas; Fortin, Maryse; Aldebeyan, Sultan; Jarzem, Peter; Ouellet, Jean; Weber, Michael H

    2016-12-01

    Study Design Retrospective cohort study. Objective To identify predictive factors for blood transfusion and associated complications in lumbar and thoracic fusion surgeries. Methods The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients who underwent lumbar or thoracic fusion from 2010 to 2013. Multivariate analysis was used to determine predictive factors and postoperative complications associated with transfusion. Results Out of 13,695 patients, 13,170 had lumbar fusion and 525 had thoracic fusion. The prevalence of transfusion was 31.8% for thoracic and 17.0% for lumbar fusion. The multivariate analysis showed that age between 50 and 60, age between 61 and 70, age > 70, dyspnea, American Society of Anesthesiologists class 3, bleeding disease, multilevel surgery, extended surgical time, return to operation room, and higher preoperative blood urea nitrogen (BUN) were predictors of blood transfusion for lumbar fusion. Multilevel surgery, preoperative BUN, and extended surgical time were predictors of transfusion for thoracic fusion. Patients receiving transfusions who underwent lumbar fusion were more likely to develop wound infection, venous thromboembolism, pulmonary embolism, and myocardial infarction and had longer hospital stay. Patients receiving transfusions who underwent thoracic fusion were more likely to have extended hospital stay. Conclusion This study characterizes incidence, predictors, and postoperative complications associated with blood transfusion in thoracic and lumbar fusion. Pre- and postoperative planning for patients deemed to be at high risk of requiring blood transfusion might reduce postoperative complications in this population.

  4. Assessment of Prospectively Assigned Likert Scores for Targeted Magnetic Resonance Imaging-Transrectal Ultrasound Fusion Biopsies in Patients with Suspected Prostate Cancer.

    Science.gov (United States)

    Costa, Daniel N; Lotan, Yair; Rofsky, Neil M; Roehrborn, Claus; Liu, Alexander; Hornberger, Brad; Xi, Yin; Francis, Franto; Pedrosa, Ivan

    2016-01-01

    We assess the performance of prospectively assigned magnetic resonance imaging based Likert scale scores for the detection of clinically significant prostate cancer, and analyze the pre-biopsy imaging variables associated with increased cancer detection using targeted magnetic resonance imaging-transrectal ultrasound fusion biopsy. In this retrospective review of prospectively generated data including men with abnormal multiparametric prostate magnetic resonance imaging (at least 1 Likert score 3 or greater lesion) who underwent subsequent targeted magnetic resonance imaging-transrectal ultrasound fusion biopsy, we determined the association between different imaging variables (Likert score, lesion size, lesion location, prostate volume, radiologist experience) and targeted biopsy positivity rate. We also compared the detection of clinically significant cancer according to Likert scale scores. Tumors with high volume (50% or more of any core) Gleason score 3+4 or any tumor with greater Gleason score were considered clinically significant. Each lesion served as the elementary unit for analysis. We used logistic regression for univariate and multivariate (stepwise selection) analysis to assess for an association between targeted biopsy positivity rate and each tested variable. The relationship between Likert scale and Gleason score was evaluated using the Spearman correlation coefficient. A total of 161 men with 244 lesions met the study eligibility criteria. Targeted biopsies diagnosed cancer in 41% (66 of 161) of the men and 41% (99 of 244) of the lesions. The Likert score was the strongest predictor of targeted biopsy positivity (OR 3.7, p Likert score, lesion size and prostate volume were significant predictors of targeted biopsy positivity. Higher Likert scores were also associated with increased detection of clinically significant tumors (p Likert scale score used to convey the degree of suspicion on multiparametric magnetic resonance imaging is the strongest

  5. Early experience with X-ray magnetic resonance fusion for low-flow vascular malformations in the pediatric interventional radiology suite

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Tiffany J. [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Keck School of Medicine of the University of Southern California, Los Angeles, CA (United States); Girard, Erin [Siemens Corporation, Corporate Technology, Princeton, NJ (United States); Shellikeri, Sphoorti; Vossough, Arastoo; Ho-Fung, Victor; Cahill, Anne Marie [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Setser, Randolph [Siemens Medical Solutions USA, Inc., Hoffman Estates, IL (United States)

    2016-03-15

    This technical innovation describes our experience using an X-ray magnetic resonance fusion (XMRF) software program to overlay 3-D MR images on real-time fluoroscopic images during sclerotherapy procedures for vascular malformations at a large pediatric institution. Five cases have been selected to illustrate the application and various clinical utilities of XMRF during sclerotherapy procedures as well as the technical limitations of this technique. The cases demonstrate how to use XMRF in the interventional suite to derive additional information to improve therapeutic confidence with regards to the extent of lesion filling and to guide clinical management in terms of intraprocedural interventional measures. (orig.)

  6. Fusion research at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    1982-03-01

    The ORNL Fusion Program includes the experimental and theoretical study of two different classes of magnetic confinement schemes - systems with helical magnetic fields, such as the tokamak and stellarator, and the ELMO Bumpy Torus (EBT) class of toroidally linked mirror systems; the development of technologies, including superconducting magnets, neutral atomic beam and radio frequency (rf) heating systems, fueling systems, materials, and diagnostics; the development of databases for atomic physics and radiation effects; the assessment of the environmental impact of magnetic fusion; and the design of advanced demonstration fusion devices. The program involves wide collaboration, both within ORNL and with other institutions. The elements of this program are shown. This document illustrates the program's scope; and aims by reviewing recent progress.

  7. Fusion in the Era of Burning Plasma Studies: Workforce Planning for 2004 to 2014. Final report to FESA C

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2004-03-29

    This report has been prepared in response to Dr. R. Orbach’s request of the Fusion Energy Sciences Advisory Committee (FESAC) to “address the issue of workforce development in the U.S. fusion program.” The report addresses three key questions: what is the current status of the fusion science, technology, and engineering workforce; what is the workforce that will be needed and when it will be needed to ensure that the U.S. is an effective partner in ITER and to enable the U.S. to successfully carry out the fusion program; and, what can be done to ensure a qualified, diversified, and sufficiently large workforce and a pipeline to maintain that workforce? In addressing the charge, the Panel considers a workforce that allows for a vigorous national program of fusion energy research that includes participation in magnetic fusion (ITER) and inertial fusion (NIF) burning plasma experiments.

  8. Proposal for magnetic/electromagnetic fields protection norms on national level

    Directory of Open Access Journals (Sweden)

    Đorđević Drago

    2008-01-01

    Full Text Available Introduction The modern life is not possible without application of magnetic/electromagnetic fields, which can be both helpful and harmful for human body. Influence of magnetic/electromagnetic fields on biological systems The non-ionizing radiation, especially magnetic/electromagnetic fields of all frequencies (0-300 GHz, can have many harmful effects on the human health that is confirmed by numerous epidemiological studies, studies with volunteers, animal studies, and in vitro studies. Proposal for magnetic/electromagnetic fields protection norms Proposal for magnetic/electromagnetic fields protection norms on national level based on the WHO Program for Environment, International Commission on Non-Ionizing Radiation Protection (ICNIRP], and WHO International EMF Project. Conclusion Protection from harmful effects of the magnetic/electromagnetic fields is still a great problem in many countries of modern society - huge costs, impaired quality of life, and more important, damage to the human health. Numerous data and publications of harmful effects of the magnetic/electromagnetic fields represents one's country basic necessary documentation for making decisions and law documents for protection norms on national level concerning the health maintenance according to the ICNIRP normatives.

  9. Fusion safety program Annual report, Fiscal year 1995

    Energy Technology Data Exchange (ETDEWEB)

    Longhurst, G.R.; Cadwallader, L.C.; Carmack, W.J. [and others

    1995-12-01

    This report summarizes the major activities of the Fusion Safety Program in FY-95. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory, and Lockheed Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL, at other DOE laboratories, and at other institutions. Among the technical areas covered in this report are tritium safety, beryllium safety, chemical reactions and activation product release, safety aspects of fusion magnet systems, plasma disruptions, risk assessment failure rate database development, and safety code development and application to fusion safety issues. Most of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed by the Fusion Safety Program for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor and the technical support for commercial fusion facility conceptual design studies. A final activity described is work to develop DOE Technical Standards for Safety of Fusion Test Facilities.

  10. Fusion Safety Program annual report, fiscal year 1994

    Science.gov (United States)

    Longhurst, Glen R.; Cadwallader, Lee C.; Dolan, Thomas J.; Herring, J. Stephen; McCarthy, Kathryn A.; Merrill, Brad J.; Motloch, Chester C.; Petti, David A.

    1995-03-01

    This report summarizes the major activities of the Fusion Safety Program in fiscal year 1994. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and Lockheed Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL, at other DOE laboratories, and at other institutions, including the University of Wisconsin. The technical areas covered in this report include tritium safety, beryllium safety, chemical reactions and activation product release, safety aspects of fusion magnet systems, plasma disruptions, risk assessment failure rate data base development, and thermalhydraulics code development and their application to fusion safety issues. Much of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed by the Fusion Safety Program for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor and of the technical support for commercial fusion facility conceptual design studies. A major activity this year has been work to develop a DOE Technical Standard for the safety of fusion test facilities.

  11. Fusion development and technology

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, D.B.

    1992-01-01

    This report discusses the following: superconducting magnet technology; high field superconductors; advanced magnetic system and divertor development; poloidal field coils; gyrotron development; commercial reactor studies--aries; ITER physics: alpha physics and alcator R D for ITER; lower hybrid current drive and heating in the ITER device; ITER superconducting PF scenario and magnet analysis; ITER systems studies; and safety, environmental and economic factors in fusion development.

  12. The Bi-2212 conductor and magnet program at the National High Magnetic Field Laboratory

    CERN Document Server

    Larbalestier, D; Jiang, J; Kametani, F; LoSchiavo, M; Myers, D; Schwartz, J; Shen, T; Trociewitz, U

    2009-01-01

    The NHMFL has had a long running program to develop Bi2Sr2CaCu2Ox (Bi2212) for high field magnets. The recent development of round wire Bi2212 (RW2212) has strengthened the effort to develop solenoid magnets with fields substantially greater than can be achieved with Nb3Sn. The present paper briefly summarizes some of the results obtained at the NHMFL in the past 12 months. It summarizes the talk given by David Larbalestier at WAMSDO on May 24, 2008. Much of the work is ongoing and will be reported in the normal peer reviewed literature in late 2008.

  13. Adjacent segment disease after anterior cervical decompression and fusion: analysis of risk factors on X-ray and magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    Zhao Yanbin; Sun Yu; Zhou Feifei; Wang Shaobo; Zhang Fengshan; Pan Shengfa

    2014-01-01

    Background Adjacent segment disease (ASD) is common after cervical fusion.The aim of this study was to evaluate the risk factors for ASD on X-ray and magnetic resonance imaging (MRI).Methods Patients included in this study had received revision surgeries after developing symptomatic ASD following anterior decompression and fusion.A control group that had not developed ASD was matched 1:1 by follow-up time and fusion segments.Plate-to-disc distances (PDDs),developmental cervical canal stenosis on X-ray,cervical disc degeneration grading,and cervical disc bulge impingements on preoperative MRI were measured and compared between the ASD group and the control group.Results Thirty-four patients with complete radiographic data were included in the ASD group.The causative segments of ASD included nine cases of C3-4,18 cases of C4-5,three cases of C5-6,and four cases of C6-7.The ASD occurred at the upper adjacent segments in 26 patients and at the lower adjacent segments in eight patients.PDD distributions were similar between the ASD group and the control group.Developmental cervical canal stenosis was a risk factor for ASD,with an odd ratio value of 2.88.Preoperative cervical disc degenerations on MRI were similar between the ASD group and the control group.In the upper-level ASD group,the disc bulge impingement was (19.7±9.7)%,which was significantly higher than that of the control group of (11.8±4.8)%.Conclusions ASD was more likely to develop above the index level of fusion.Developmental cervical canal stenosis and greater disc bulge impingement may be risk factors for the development of ASD.

  14. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems.

  15. Building Magnets at Brookhaven National Laboratory - An Account

    Energy Technology Data Exchange (ETDEWEB)

    Willen, E. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-06-01

    The development of superconducting wire and cable in the late 20th century enabled high field magnets and thus much higher beam collision energies in accelerators. These higher collision energies have allowed experiments to probe further into the structure of matter at the most fundamental, subatomic level. The behavior of the early universe, where these high energies prevailed, and its evolution over time are what these experiments seek to investigate. The subject has aroused the curiosity of not only scientists but of the public as well and has facilitated the support needed to build and operate such expensive machines and experiments. The path forward has not been easy, however. Success in most projects has been mixed with failure, progress with ineptitude. The building of high energy accelerators is mostly a story of capable people doing their best to develop new and unusual technology toward some defined goal, with success and failure in uneven measure along the way. It is also a story of administrative imperatives that have had unpredictable effects on a project’s success, depending mostly on the people in the administrative roles and the decisions that they have made.

  16. Building Magnets at Brookhaven National Laboratory: A Condensed Account

    Science.gov (United States)

    Willen, Erich

    2017-09-01

    The development of superconducting wire and cable in the late twentieth century enabled high-field magnets and thus much higher beam-collision energies in accelerators. These higher collision energies have allowed experimentalists to probe further into the structure of matter at the most fundamental, subatomic level. The behavior of the early universe, where these high energies prevailed, and its evolution over time are the realm their experiments seek to investigate. The subject has aroused the curiosity of the public as well as scientists and has facilitated the support needed to build and operate such expensive machines and experiments. The path forward has not been easy, however. Success in most projects has been mixed with failure, progress with ineptitude. The building of high energy accelerators is mostly a story of capable people doing their best to develop new and unusual technology toward some defined goal, facing both success and failure along the way. It is also a story of administrative imperatives that had unpredictable effects on a project's success, depending mostly on the people in the administrative roles and the decisions that they made.

  17. Fusion ignition research experiment

    Energy Technology Data Exchange (ETDEWEB)

    Dale Meade

    2000-07-18

    Understanding the properties of high gain (alpha-dominated) fusion plasmas in an advanced toroidal configuration is the largest remaining open issue that must be addressed to provide the scientific foundation for an attractive magnetic fusion reactor. The critical parts of this science can be obtained in a compact high field tokamak which is also likely to provide the fastest and least expensive path to understanding alpha-dominated plasmas in advanced toroidal systems.

  18. Development of high field magnets at the National Research Institute for Metals. Kinzoku zairyo gijutsu kenkyusho ni okeru kojikai magnet gun no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kiyoshi, T.; Inoue, K.; Maeda, H. (National Research Inst. for Metals, Tsukuba (Japan))

    1993-06-20

    Sinece 1988, the Scince and Technology Agency has initiated the superconductor multicore project, which has a purpose of the versatile study on the high temperature superconducting materials of the oxide series. The National Research Institute for Metals is in charge of 5 cores out of them, and in the performance evaluation core which is one of them, the development of each kind of the high field magnets is being advanced for evaluating the characteristics under the high magnetic field. As the magnets, including the 40T class hybrid magnet which generates the steady state magnetic field of 40T, the superconducting magnet of 20T with a large diameter which generates the magnetic field over 20T with a superconductor, the condenser bank system for the pulse magnet to generate the pulse magnetic field up to 80T, and the ultra-precise magnet system which generates the magnetic field with a high uniformity will be consolidated. Keeping pace with a removal of the National Research Institute for Metals to Tsukuba, the construction of the strong magnetic field station is being advanced in the Sakura area. These several kinds of magnets are scheduled to be used in turn for the international joint study. 33 refs., 5 figs., 4 tabs.

  19. First magnet constructed for the LHC by Brookhaven National Laboratory, USA

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    CERN has taken delivery of the first US-built contribution to the LHC. The 25-tonne interaction-region dipole magnet, which will guide the LHC´s two counter-rotating beams of protons into collision, was built at the US Brookhaven National Laboratory. It is the first of 20 that the laboratory will ultimately provide and took nine months for more than 100 scientists, engineers and technicians to construct. Brookhaven´s Superconducting Magnet Division is now building the remaining 19 magnets, which will be shipped to CERN later this year. They are provided for the LHC under the terms of a 1998 agreement between CERN and the US Department of Energy and National Science Foundation.

  20. Design and Performance of the First Dual-Coil Magnet at the Wuhan National High Magnetic Field Center

    Science.gov (United States)

    Peng, T.; Sun, Q. Q.; Zhang, X.; Xu, Q.; Xiao, H. X.; Herlach, F.; Pan, Y.; Li, L.

    2013-03-01

    The first 80 T dual-coil magnet was manufactured and tested at the Wuhan National High Magnetic Field Center (WHMFC). The inner coil consists of 8 layers of 2.8 mm × 4.3 mm CuNb microcomposite wire developed in China; the bore diameter is 14 mm and the outer diameter 135 mm. The outer coil was wound directly on the inner coil with 12 layers of 3 mm × 6 mm soft copper. Each conductor layer of both coils was reinforced by Zylon/epoxy composite. The inner and outer coil were driven by a 1.6 MJ/5.12 mF capacitor bank and by eight 1 MJ/3.2 mF modules, respectively. At the voltage of 14.3 kV for the inner coil and 22 kV for the outer coil, the inner and outer coils produced peak fields of 48.5 T and 34.5 T respectively, which gave a total field of 83 T. This was the first combined operation of the new capacitor banks installed at the WHMFC. We present details of the design, manufacture and test of the dual-coil magnet and discuss crucial material properties. Based on this experience, a second dual-coil magnet will be designed; the enhanced design will be discussed. With the total energy of 12.6 MJ, peak field up to 90 T is expected.

  1. Accelerator and fusion research division. 1992 Summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    This report contains brief discussions on research topics in the following area: Heavy-Ion Fusion Accelerator Research; Magnetic Fusion Energy; Advanced Light Source; Center for Beam Physics; Superconducting Magnets; and Bevalac Operations.

  2. Accelerator & Fusion Research Division 1991 summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    This report discusses research projects in the following areas: Heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; superconducting magnets; and bevalac operations.

  3. Accelerator Fusion Research Division 1991 summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    Berkner, Klaus H.

    1991-12-01

    This report discusses research projects in the following areas: Heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; superconducting magnets; and bevalac operations.

  4. Fusion reactor materials. Semiannual progress report for period ending September 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rowcliffe, A.F.; Burn, G.L.; Knee`, S.S.; Dowker, C.L. [comps.

    1994-02-01

    This is the fifteenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; Special purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the U.S. Department of Energy. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  5. Compact fusion reactors

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Fusion research is currently to a large extent focused on tokamak (ITER) and inertial confinement (NIF) research. In addition to these large international or national efforts there are private companies performing fusion research using much smaller devices than ITER or NIF. The attempt to achieve fusion energy production through relatively small and compact devices compared to tokamaks decreases the costs and building time of the reactors and this has allowed some private companies to enter the field, like EMC2, General Fusion, Helion Energy, Lawrenceville Plasma Physics and Lockheed Martin. Some of these companies are trying to demonstrate net energy production within the next few years. If they are successful their next step is to attempt to commercialize their technology. In this presentation an overview of compact fusion reactor concepts is given.

  6. Secondary Nuclear Reactions in Magneto-Inertial Fusion Plasmas

    Science.gov (United States)

    Knapp, Patrick

    2014-10-01

    The goal of Magneto-Inertial Fusion (MIF) is to relax the extreme pressure requirements of inertial confinement fusion by magnetizing the fuel. Understanding the level of magnetization at stagnation is critical for charting the performance of any MIF concept. We show here that the secondary nuclear reactions in magnetized deuterium plasma can be used to infer the magnetic field-radius product (BR), the critical confinement parameter for MIF. The secondary neutron yields and spectra are examined and shown to be extremely sensitive to BR. In particular, embedded magnetic fields are shown to affect profoundly the isotropy of the secondary neutron spectra. Detailed modeling of these spectra along with the ratio of overall secondary to primary neutron yields is used to form the basis of a diagnostic technique used to infer BR at stagnation. Effects of gradients in density, temperature and magnetic field strength are examined, as well as other possible non-uniform fuel configurations. Computational results employing a fully kinetic treatment of charged reaction product transport and Monte Carlo treatment of secondary reactions are compared to results from recent experiments at Sandia National Laboratories' Z machine testing the MAGnetized Liner Inertial Fusion (MagLIF) concept. The technique reveals that the charged reaction products were highly magnetized in these experiments. Implications for eventual ignition-relevant experiments with deuterium-tritium fuel are discussed. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  7. Safety Problems of Electric and Magnetic Fields and Experimental Magnetic Fusion Facilities 3.Biological Effects of Low-Frequency Electromagnetic Fields

    Science.gov (United States)

    Miyakoshi, Junji

    The possible health hazard of exposure to low-frequency magnetic fields has become an issue of considerable public concern. Although many epidemiological studies have done, the results are inconsistent to explain an association between exposure to the magnetic fields in the environment and apparent cancer. In in vitro studies, the existence of the effects of the magnetic fields at low flux density has also been contradictory in various reports. This paper reviews studies on cellular and molecular effects of low-frequency magnetic fields.

  8. Catalysed fusion

    CERN Document Server

    Farley, Francis

    2012-01-01

    A sizzling romance and a romp with subatomic particles at CERN. Love, discovery and adventure in the city where nations meet and beams collide. Life in a large laboratory. As always, the challenges are the same. Who leads? Who follows? Who succeeds? Who gets the credit? Who gets the women or the men? Young Jeremy arrives in CERN and joins the quest for green energy. Coping with baffling jargon and manifold dangers, he is distracted by radioactive rats, lovely ladies and an unscrupulous rival. Full of doubts and hesitations, he falls for a dazzling Danish girl, who leads him astray. His brilliant idea leads to a discovery and a new route to cold fusion. But his personal life is scrambled. Does it bring fame or failure? Tragedy or triumph?

  9. Role of high-field intraoperative magnetic resonance imaging on a multi-image fusion-guided stereotactic biopsy of the basal ganglia: A case report.

    Science.gov (United States)

    Sun, Xiang; Chen, Zhijuan; Yang, Shuyuan; Zhang, Jianning; Yue, Shuyuan; Wang, Zengguang; Yang, Weidong

    2015-01-01

    The aim of the present case study was to investigate the advantages of intraoperative magnetic resonance imaging (iMRI) on the real-time guidance and monitoring of a stereotactic biopsy. The study describes a patient with intracranial lesions, which were examined by conventional MRI and diffusion tensor imaging using a 1.5T intraoperative MRI system. The digital and pre-operative positron emission/computed tomography image data were transferred to a BrainLAB planning workstation, and a variety of images were automatically fused. The BrainLAB software was then used to reconstruct the corticospinal tract (CST) and create a three-dimensional display of the anatomical association between the CST and the brain lesions. A Leksell surgical planning workstation was used to identify the ideal target site and a reasonable needle track for the biopsy. The 1.5T iMRI was used to effectively monitor the intracranial condition during the brain biopsy procedure. Post-operatively, the original symptoms of the patient were not aggravated and no further neurological deficits were apparent. The histopathological diagnosis of non-Hodgkin's B-cell lymphoma was made. Using high-field iMRI, the multi-image fusion-guided stereotactic brain biopsy allows for a higher positive rate of biopsy and a lower incidence of complications. The approach of combining multi-image fusion images with the frame-based stereotactic biopsy may be clinically useful for intracranial lesions of deep functional areas.

  10. Establishment of an Institute for Fusion Studies. Technical progress report, 1 November 1993--31 October 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hazeltine, R.D.

    1994-07-01

    The Institute for Fusion Studies is a national center for theoretical fusion plasma physics research. Its purposes are: (1) to conduct research on theoretical questions concerning the achievement of controlled fusion energy by means of magnetic confinement--including both fundamental problems of long-range significance, as well as shorter-term issues; (2) to serve as a national and international center for information exchange by hosting exchange visits, conferences, and workshops; (3) and to train students and postdoctoral research personnel for the fusion energy program and plasma physics research areas. The theoretical research results obtained by the Institute contribute to the progress of nuclear fusion research, whose goal is the development of fusion power as a basic energy source. Close collaborative relationships have been developed with other university and national laboratory fusion groups, both in the US and abroad. In addition to its primary focus on mainstream fusion physics, the Institute is also involved with research in fusion-sidestream fields, such as advanced computing techniques, nonlinear dynamics, space plasmas and astrophysics, statistical mechanics, fluid dynamics, and accelerator physics. Important research discoveries are briefly described.

  11. Developing a frame of thermoplastic immobilization head and neck magnetic resonance antennas image fusion CT-MRI radiotherapy; Desarrollo de un frame de inmovilizacion termoplastica de cabeza y cuello en antenas de resonance magnetic para fusion de imagenes radioterapicas CT-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Miranda, S.; Munoz Carmona, D. M.; Ortiz Seidel, M.; Cano Duran, P.

    2011-07-01

    In case you want to merge neck injuries, the degrees of freedom and geometry of this anatomical region make for fusion applications have a limited success. To overcome these problems we decided to enter the detention of patients also in the resonance, but we dealt with the problem that the antenna resonance leaves a very small space for the patient's head. In addition, the carbon frame is electrically conductive, which is not entirely suitable for resonance images. So we designed a new concept of frame (FRAME CT-MRI) and a new material that people can use in nuclear magnetic resonance.

  12. Cold nuclear fusion

    Directory of Open Access Journals (Sweden)

    Huang Zhenqiang Huang Yuxiang

    2013-10-01

    Full Text Available In normal temperature condition, the nuclear force constraint inertial guidance method, realize the combination of deuterium and tritium, helium and lithium... And with a magnetic moment of light nuclei controlled cold nuclear collide fusion, belongs to the nuclear energy research and development in the field of applied technology "cold nuclear collide fusion". According to the similarity of the nuclear force constraint inertial guidance system, the different velocity and energy of the ion beam mixing control, developed ion speed dc transformer, it is cold nuclear fusion collide, issue of motivation and the nuclear power plant start-up fusion and power transfer system of the important equipment, so the merger to apply for a patent

  13. Fusion Studies in Japan

    Science.gov (United States)

    Ogawa, Yuichi

    2016-05-01

    A new strategic energy plan decided by the Japanese Cabinet in 2014 strongly supports the steady promotion of nuclear fusion development activities, including the ITER project and the Broader Approach activities from the long-term viewpoint. Atomic Energy Commission (AEC) in Japan formulated the Third Phase Basic Program so as to promote an experimental fusion reactor project. In 2005 AEC has reviewed this Program, and discussed on selection and concentration among many projects of fusion reactor development. In addition to the promotion of ITER project, advanced tokamak research by JT-60SA, helical plasma experiment by LHD, FIREX project in laser fusion research and fusion engineering by IFMIF were highly prioritized. Although the basic concept is quite different between tokamak, helical and laser fusion researches, there exist a lot of common features such as plasma physics on 3-D magnetic geometry, high power heat load on plasma facing component and so on. Therefore, a synergetic scenario on fusion reactor development among various plasma confinement concepts would be important.

  14. Osteoclast Fusion

    DEFF Research Database (Denmark)

    Marie Julie Møller, Anaïs; Delaissé, Jean-Marie; Søe, Kent

    2017-01-01

    suggesting that fusion partners may specifically select each other and that heterogeneity between the partners seems to play a role. Therefore, we set out to directly test the hypothesis that fusion factors have a heterogenic involvement at different stages of nuclearity. Therefore, we have analyzed...... on the nuclearity of fusion partners. While CD47 promotes cell fusions involving mono-nucleated pre-osteoclasts, syncytin-1 promotes fusion of two multi-nucleated osteoclasts, but also reduces the number of fusions between mono-nucleated pre-osteoclasts. Furthermore, CD47 seems to mediate fusion mostly through......Investigations addressing the molecular keys of osteoclast fusion are primarily based on end-point analyses. No matter if investigations are performed in vivo or in vitro the impact of a given factor is predominantly analyzed by counting the number of multi-nucleated cells, the number of nuclei per...

  15. Magnetic reconnection in plasma under inertial confinement fusion conditions driven by heat flux effects in Ohm's law.

    Science.gov (United States)

    Joglekar, A S; Thomas, A G R; Fox, W; Bhattacharjee, A

    2014-03-14

    In the interaction of high-power laser beams with solid density plasma there are a number of mechanisms that generate strong magnetic fields. Such fields subsequently inhibit or redirect electron flows, but can themselves be advected by heat fluxes, resulting in complex interplay between thermal transport and magnetic fields. We show that for heating by multiple laser spots reconnection of magnetic field lines can occur, mediated by these heat fluxes, using a fully implicit 2D Vlasov-Fokker-Planck code. Under such conditions, the reconnection rate is dictated by heat flows rather than Alfvènic flows. We find that this mechanism is only relevant in a high β plasma. However, the Hall parameter ωcτei can be large so that thermal transport is strongly modified by these magnetic fields, which can impact longer time scale temperature homogeneity and ion dynamics in the system.

  16. Magnetic reconnection in plasma under inertial confinement fusion conditions driven by heat flux effects in Ohm's law

    CERN Document Server

    Joglekar, A S; Fox, W; Bhattacharjee, A

    2015-01-01

    In the interaction of high-power laser beams with solid density plasma there are a number of mechanisms that generate strong magnetic fields. Such fields subsequently inhibit or redirect electron flows, but can themselves be advected by heat fluxes, resulting in complex interplay between thermal transport and magnetic fields.We show that for heating by multiple laser spots reconnection of magnetic field lines can occur, mediated by these heat fluxes, using a fully implicit 2D Vlasov-Fokker-Planck code. Under such conditions, the reconnection rate is dictated by heat flows rather than Alfv\\`enic flows. We find that this mechanism is only relevant in a high $\\beta$ plasma. However, the Hall parameter $\\omega_c \\tau_{ei}$ can be large so that thermal transport is strongly modified by these magnetic fields, which can impact longer time scale temperature homogeneity and ion dynamics in the system.

  17. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  18. Muon catalyzed fusion

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, K. [Advanced Meson Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Nagamine, K. [Muon Science Laboratory, IMSS-KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Matsuzaki, T. [Advanced Meson Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawamura, N. [Muon Science Laboratory, IMSS-KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2005-12-15

    The latest progress of muon catalyzed fusion study at the RIKEN-RAL muon facility (and partly at TRIUMF) is reported. The topics covered are magnetic field effect, muon transfer to {sup 3}He in solid D/T and ortho-para effect in dd{mu} formation.

  19. Generalized Lawson Criteria for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Tipton, Robert E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-08-27

    The Lawson Criterion was proposed by John D. Lawson in 1955 as a general measure of the conditions necessary for a magnetic fusion device to reach thermonuclear ignition. Over the years, similar ignition criteria have been proposed which would be suitable for Inertial Confinement Fusion (ICF) designs. This paper will compare and contrast several ICF ignition criteria based on Lawson’s original ideas. Both analytical and numerical results will be presented which will demonstrate that although the various criteria differ in some details, they are closely related and perform similarly as ignition criteria. A simple approximation will also be presented which allows the inference of each ignition parameter directly from the measured data taken on most shots fired at the National Ignition Facility (NIF) with a minimum reliance on computer simulations. Evidence will be presented which indicates that the experimentally inferred ignition parameters on the best NIF shots are very close to the ignition threshold.

  20. Seeking tools for image fusion between computed tomography, structural and functional magnetic resonance methods for applications in neurosurgery; Ferramentas para fusao de imagens dos metodos de tomografia computadorizada, ressonancia magnetica e ressonancia magnetica funcional para aplicacao pre-neurocirurgica

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Liana Guerra Sanches da, E-mail: liana@einstein.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo (SP) (Brazil); Amaro Junior, Edson [Faculdade de Medicina, Universidade de Sao Paulo - USP, Sao Paulo, SP (Brazil). Deptartamento de Diagnostico por Imagem; Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    To evaluate tools for the fusion of images generated by tomography and structural and functional magnetic resonance imaging. Methods: Magnetic resonance and functional magnetic resonance imaging were performed while a volunteer who had previously undergone cranial tomography performed motor and somatosensory tasks in a 3-Tesla scanner. Image data were analyzed with different programs, and the results were compared. Results: We constructed a flow chart of computational processes that allowed measurement of the spatial congruence between the methods. There was no single computational tool that contained the entire set of functions necessary to achieve the goal. Conclusion: The fusion of the images from the three methods proved to be feasible with the use of four free-access software programs (OsiriX, Register, MRIcro and FSL). Our results may serve as a basis for building software that will be useful as a virtual tool prior to neurosurgery. (author)

  1. Applications of Fusion Energy Sciences Research - Scientific Discoveries and New Technologies Beyond Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Amy [Univ. of Wisconsin, Madison, WI (United States); Callis, Richard [General Atomics, San Diego, CA (United States); Efthimion, Philip [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Foster, John [Univ. of Michigan, Ann Arbor, MI (United States); Keane, Christopher [Washington State Univ., Pullman, WA (United States); Onsager, Terry [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); O' Shea, Patrick [Univ. of Maryland, College Park, MD (United States)

    2015-09-01

    Since the 1950s, scientists and engineers in the U.S. and around the world have worked hard to make an elusive goal to be achieved on Earth: harnessing the reaction that fuels the stars, namely fusion. Practical fusion would be a source of energy that is unlimited, safe, environmentally benign, available to all nations and not dependent on climate or the whims of the weather. Significant resources, most notably from the U.S. Department of Energy (DOE) Office of Fusion Energy Sciences (FES), have been devoted to pursuing that dream, and significant progress is being made in turning it into a reality. However, that is only part of the story. The process of creating a fusion-based energy supply on Earth has led to technological and scientific achievements of far-reaching impact that touch every aspect of our lives. Those largely unanticipated advances, spanning a wide variety of fields in science and technology, are the focus of this report. There are many synergies between research in plasma physics (the study of charged particles and fluids interacting with self-consistent electric and magnetic fields), high-energy physics, and condensed matter physics dating back many decades. For instance, the formulation of a mathematical theory of solitons, solitary waves which are seen in everything from plasmas to water waves to Bose-Einstein Condensates, has led to an equal span of applications, including the fields of optics, fluid mechanics and biophysics. Another example, the development of a precise criterion for transition to chaos in Hamiltonian systems, has offered insights into a range of phenomena including planetary orbits, two-person games and changes in the weather. Seven distinct areas of fusion energy sciences were identified and reviewed which have had a recent impact on fields of science, technology and engineering not directly associated with fusion energy: Basic plasma science; Low temperature plasmas; Space and astrophysical plasmas; High energy density

  2. Applications of Fusion Energy Sciences Research - Scientific Discoveries and New Technologies Beyond Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Amy [Univ. of Wisconsin, Madison, WI (United States); Callis, Richard [General Atomics, San Diego, CA (United States); Efthimion, Philip [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Foster, John [Univ. of Michigan, Ann Arbor, MI (United States); Keane, Christopher [Washington State Univ., Pullman, WA (United States); Onsager, Terry [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); O' Shea, Patrick [Univ. of Maryland, College Park, MD (United States)

    2015-09-01

    Since the 1950s, scientists and engineers in the U.S. and around the world have worked hard to make an elusive goal to be achieved on Earth: harnessing the reaction that fuels the stars, namely fusion. Practical fusion would be a source of energy that is unlimited, safe, environmentally benign, available to all nations and not dependent on climate or the whims of the weather. Significant resources, most notably from the U.S. Department of Energy (DOE) Office of Fusion Energy Sciences (FES), have been devoted to pursuing that dream, and significant progress is being made in turning it into a reality. However, that is only part of the story. The process of creating a fusion-based energy supply on Earth has led to technological and scientific achievements of far-reaching impact that touch every aspect of our lives. Those largely unanticipated advances, spanning a wide variety of fields in science and technology, are the focus of this report. There are many synergies between research in plasma physics, (the study of charged particles and fluids interacting with self-consistent electric and magnetic fields), high-energy physics, and condensed matter physics dating back many decades. For instance, the formulation of a mathematical theory of solitons, solitary waves which are seen in everything from plasmas to water waves to Bose-Einstein Condensates, has led to an equal span of applications, including the fields of optics, fluid mechanics and biophysics. Another example, the development of a precise criterion for transition to chaos in Hamiltonian systems, has offered insights into a range of phenomena including planetary orbits, two-person games and changes in the weather. Seven distinct areas of fusion energy sciences were identified and reviewed which have had a recent impact on fields of science, technology and engineering not directly associated with fusion energy: Basic plasma science; Low temperature plasmas; Space and astrophysical plasmas; High energy density

  3. Fusion rings and fusion ideals

    DEFF Research Database (Denmark)

    Andersen, Troels Bak

    by the so-called fusion ideals. The fusion rings of Wess-Zumino-Witten models have been widely studied and are well understood in terms of precise combinatorial descriptions and explicit generating sets of the fusion ideals. They also appear in another, more general, setting via tilting modules for quantum...

  4. Fusion neutronics

    CERN Document Server

    Wu, Yican

    2017-01-01

    This book provides a systematic and comprehensive introduction to fusion neutronics, covering all key topics from the fundamental theories and methodologies, as well as a wide range of fusion system designs and experiments. It is the first-ever book focusing on the subject of fusion neutronics research. Compared with other nuclear devices such as fission reactors and accelerators, fusion systems are normally characterized by their complex geometry and nuclear physics, which entail new challenges for neutronics such as complicated modeling, deep penetration, low simulation efficiency, multi-physics coupling, etc. The book focuses on the neutronics characteristics of fusion systems and introduces a series of theories and methodologies that were developed to address the challenges of fusion neutronics, and which have since been widely applied all over the world. Further, it introduces readers to neutronics design’s unique principles and procedures, experimental methodologies and technologies for fusion systems...

  5. Magnetic Fusion Energy Program. Volume I. Introduction, technical summaries, list of publications, etc. , Appendices A-K. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Aamodt, R. E.; Byrne, R. N.; Catto, P. J.

    1979-12-01

    An abstract was prepared for the progress summary on transport theory for open and closed magnetic configurations. Seven abstracts were prepared for included appendices of more detailed work on individual devices. Also included is a list of publications, technical presentations, and DOE program contributions. (MOW)

  6. Investigation of gamma-ray time shifts caused by capsule areal density variations in inertial confinement fusion experiments at the national ignition facility and the omega facility

    Science.gov (United States)

    Grafil, Elliot M.

    This thesis describes work on Cherenkov based gamma detectors used as diag- nostics at Inertial Confinement Fusion (ICF) facilities. The first part describes the calibration and commissioning of the Gamma Reaction History diagnostic which is a four cell Cherenkov detector array used to characterize the ICF implosion at the National Ignition Facility (NIF) by measuring the gamma rays generated during the fusion event. Two of the key metrics which the GRH measures are Gamma Bang Time (GBT) generated from the D(T,α)n thermonuclear burn and Ablator Peak Time (APT) caused by (n,n‧)gamma reactions in the surrounding capsule ablator. Simulations of ignition capsules predict that GBT and APT should be time synchronized. After GRH commissioning, the array was used during first year of NIF operation in the National Ignition Campaign. Contrary to expectations, time shifts between GBT and APT of order 10s of picoseconds were observed. In order to further investigate the possibility of these time shifts in view of testing both instrument and code credibility an ICF shot campaign at the smaller OMEGA facility in Rochester was devised. It was performed during two full shot days in April of 2013 and 2014 and confirmed in principle the viability of the Cherenkov detector approach but raised additional questions regarding the credibility of the simulation codes used to describe ICF experiments. Specifically the measurements show that the understanding of temporal behavior of GBT vs APT may not be properly modeled in the DRACO code used at OMEGA. In view of the OMEGA results which showed no time shifts between GBT and APT, the readout and timing synchronization system of the GRH setup at the NIF was reevaluated in the framework of this thesis. Motivated by the results, which highlighted the use of wrong optical fiber diameters and possible problems with the installed variable optical attenuators, the NIF equipment has been updated over the recent months and new timing tests will

  7. Aerial radiometric and magnetic survey: Socorro National Topographic Map, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-28

    The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the Socorro National Topographic Map NI13-4 is presented in this report. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets of profiled data for each line are included, with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included.

  8. Aerial radiometric and magnetic survey, San Angelo National Topographic Map: Texas, West Texas Project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the San Angelo National Topographic Map NH14-1 are presented. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium, and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets of profiled data for each line are included, with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included.

  9. Aerial radiometric and magnetic survey: Perryton National Topographic Map, Texas/Oklahoma/Kansas. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the Perryton National Topographic Map NJ14-10 are presented. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets of profiled data for each line are included, with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included also.

  10. Nonlinear Theoretical Tools for Fusion-related Microturbulence: Historical Evolution, and Recent Applications to Stochastic Magnetic Fields, Zonal-flow Dynamics, and Intermittency

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Krommes

    2009-05-19

    Fusion physics poses an extremely challenging, practically complex problem that does not yield readily to simple paradigms. Nevertheless, various of the theoretical tools and conceptual advances emphasized at the KaufmanFest 2007 have motivated and/or found application to the development of fusion-related plasma turbulence theory. A brief historical commentary is given on some aspects of that specialty, with emphasis on the role (and limitations) of Hamiltonian/symplectic approaches, variational methods, oscillation-center theory, and nonlinear dynamics. It is shown how to extract a renormalized ponderomotive force from the statistical equations of plasma turbulence, and the possibility of a renormalized K-χ theorem is discussed. An unusual application of quasilinear theory to the problem of plasma equilibria in the presence of stochastic magnetic fields is described. The modern problem of zonal-flow dynamics illustrates a confluence of several techniques, including (i) the application of nonlinear-dynamics methods, especially center-manifold theory, to the problem of the transition to plasma turbulence in the face of self-generated zonal flows; and (ii) the use of Hamiltonian formalism to determine the appropriate (Casimir) invariant to be used in a novel wave-kinetic analysis of systems of interacting zonal flows and drift waves. Recent progress in the theory of intermittent chaotic statistics and the generation of coherent structures from turbulence is mentioned, and an appeal is made for some new tools to cope with these interesting and difficult problems in nonlinear plasma physics. Finally, the important influence of the intellectually stimulating research environment fostered by Prof. Allan Kaufman on the author's thinking and teaching methodology is described.

  11. Identification of Threshold Prostate Specific Antigen Levels to Optimize the Detection of Clinically Significant Prostate Cancer by Magnetic Resonance Imaging/Ultrasound Fusion Guided Biopsy

    Science.gov (United States)

    Shakir, Nabeel A.; George, Arvin K.; Siddiqui, M. Minhaj; Rothwax, Jason T.; Rais-Bahrami, Soroush; Stamatakis, Lambros; Su, Daniel; Okoro, Chinonyerem; Raskolnikov, Dima; Walton-Diaz, Annerleim; Simon, Richard; Turkbey, Baris; Choyke, Peter L.; Merino, Maria J.; Wood, Bradford J.; Pinto, Peter A.

    2015-01-01

    Purpose Prostate specific antigen sensitivity increases with lower threshold values but with a corresponding decrease in specificity. Magnetic resonance imaging/ultrasound targeted biopsy detects prostate cancer more efficiently and of higher grade than standard 12-core transrectal ultrasound biopsy but the optimal population for its use is not well defined. We evaluated the performance of magnetic resonance imaging/ultrasound targeted biopsy vs 12-core biopsy across a prostate specific antigen continuum. Materials and Methods We reviewed the records of all patients enrolled in a prospective trial who underwent 12-core transrectal ultrasound and magnetic resonance imaging/ultrasound targeted biopsies from August 2007 through February 2014. Patients were stratified by each of 4 prostate specific antigen cutoffs. The greatest Gleason score using either biopsy method was compared in and across groups as well as across the population prostate specific antigen range. Clinically significant prostate cancer was defined as Gleason 7 (4 + 3) or greater. Univariate and multivariate analyses were performed. Results A total of 1,003 targeted and 12-core transrectal ultrasound biopsies were performed, of which 564 diagnosed prostate cancer for a 56.2% detection rate. Targeted biopsy led to significantly more upgrading to clinically significant disease compared to 12-core biopsy. This trend increased more with increasing prostate specific antigen, specifically in patients with prostate specific antigen 4 to 10 and greater than 10 ng/ml. Prostate specific antigen 5.2 ng/ml or greater captured 90% of upgrading by targeted biopsy, corresponding to 64% of patients who underwent multiparametric magnetic resonance imaging and subsequent fusion biopsy. Conversely a greater proportion of clinically insignificant disease was detected by 12-core vs targeted biopsy overall. These differences persisted when controlling for potential confounders on multivariate analysis. Conclusions Prostate

  12. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, W. M.; Friedman, A.; Grote, D. P.; Barnard, J. J.; Cohen, R. H.; Dorf, M. A.; Lund, S. M.; Perkins, L. J.; Terry, M. R.; Logan, B. G.; Bieniosek, F. M.; Faltens, A.; Henestroza, E.; Jung, J. Y.; Kwan, J. W.; Lee, E. P.; Lidia, S. M.; Ni, P. A.; Reginato, L. L.; Roy, P. K.; Seidl, P. A.; Takakuwa, J. H.; Vay, J.-L.; Waldron, W. L.; Davidson, R. C.; Gilson, E. P.; Kaganovich, I. D.; Qin, H.; Startsev, E.; Haber, I.; Kishek, R. A.; Koniges, A. E.

    2011-03-31

    Intense heavy-ion beams have long been considered a promising driver option for inertial-fusion energy production. This paper briefly compares inertial confinement fusion (ICF) to the more-familiar magnetic-confinement approach and presents some advantages of using beams of heavy ions to drive ICF instead of lasers. Key design choices in heavy-ion fusion (HIF) facilities are discussed, particularly the type of accelerator. We then review experiments carried out at Lawrence Berkeley National Laboratory (LBNL) over the past thirty years to understand various aspects of HIF driver physics. A brief review follows of present HIF research in the US and abroad, focusing on a new facility, NDCX-II, being built at LBNL to study the physics of warm dense matter heated by ions, as well as aspects of HIF target physics. Future research directions are briefly summarized.

  13. Design and optimization of Artificial Neural Networks for the modelling of superconducting magnets operation in tokamak fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Froio, A.; Bonifetto, R.; Carli, S.; Quartararo, A.; Savoldi, L., E-mail: laura.savoldi@polito.it; Zanino, R.

    2016-09-15

    In superconducting tokamaks, the cryoplant provides the helium needed to cool different clients, among which by far the most important one is the superconducting magnet system. The evaluation of the transient heat load from the magnets to the cryoplant is fundamental for the design of the latter and the assessment of suitable strategies to smooth the heat load pulses, induced by the intrinsically pulsed plasma scenarios characteristic of today's tokamaks, is crucial for both suitable sizing and stable operation of the cryoplant. For that evaluation, accurate but expensive system-level models, as implemented in e.g. the validated state-of-the-art 4C code, were developed in the past, including both the magnets and the respective external cryogenic cooling circuits. Here we show how these models can be successfully substituted with cheaper ones, where the magnets are described by suitably trained Artificial Neural Networks (ANNs) for the evaluation of the heat load to the cryoplant. First, two simplified thermal-hydraulic models for an ITER Toroidal Field (TF) magnet and for the ITER Central Solenoid (CS) are developed, based on ANNs, and a detailed analysis of the chosen networks' topology and parameters is presented and discussed. The ANNs are then inserted into the 4C model of the ITER TF and CS cooling circuits, which also includes active controls to achieve a smoothing of the variation of the heat load to the cryoplant. The training of the ANNs is achieved using the results of full 4C simulations (including detailed models of the magnets) for conventional sigmoid-like waveforms of the drivers and the predictive capabilities of the ANN-based models in the case of actual ITER operating scenarios are demonstrated by comparison with the results of full 4C runs, both with and without active smoothing, in terms of both accuracy and computational time. Exploiting the low computational effort requested by the ANN-based models, a demonstrative optimization study

  14. Design and optimization of Artificial Neural Networks for the modelling of superconducting magnets operation in tokamak fusion reactors

    Science.gov (United States)

    Froio, A.; Bonifetto, R.; Carli, S.; Quartararo, A.; Savoldi, L.; Zanino, R.

    2016-09-01

    In superconducting tokamaks, the cryoplant provides the helium needed to cool different clients, among which by far the most important one is the superconducting magnet system. The evaluation of the transient heat load from the magnets to the cryoplant is fundamental for the design of the latter and the assessment of suitable strategies to smooth the heat load pulses, induced by the intrinsically pulsed plasma scenarios characteristic of today's tokamaks, is crucial for both suitable sizing and stable operation of the cryoplant. For that evaluation, accurate but expensive system-level models, as implemented in e.g. the validated state-of-the-art 4C code, were developed in the past, including both the magnets and the respective external cryogenic cooling circuits. Here we show how these models can be successfully substituted with cheaper ones, where the magnets are described by suitably trained Artificial Neural Networks (ANNs) for the evaluation of the heat load to the cryoplant. First, two simplified thermal-hydraulic models for an ITER Toroidal Field (TF) magnet and for the ITER Central Solenoid (CS) are developed, based on ANNs, and a detailed analysis of the chosen networks' topology and parameters is presented and discussed. The ANNs are then inserted into the 4C model of the ITER TF and CS cooling circuits, which also includes active controls to achieve a smoothing of the variation of the heat load to the cryoplant. The training of the ANNs is achieved using the results of full 4C simulations (including detailed models of the magnets) for conventional sigmoid-like waveforms of the drivers and the predictive capabilities of the ANN-based models in the case of actual ITER operating scenarios are demonstrated by comparison with the results of full 4C runs, both with and without active smoothing, in terms of both accuracy and computational time. Exploiting the low computational effort requested by the ANN-based models, a demonstrative optimization study has been

  15. EDITORIAL: Stochasticity in fusion plasmas Stochasticity in fusion plasmas

    Science.gov (United States)

    Unterberg, Bernhard

    2010-03-01

    Structure formation and transport in stochastic plasmas is a topic of growing importance in many fields of plasma physics from astrophysics to fusion research. In particular, the possibility to control transport in the boundary of confined fusion plasmas by resonant magnetic perturbations has been investigated extensively during recent years. A major research achievement was finding that the intense transient particle and heat fluxes associated with edge localized modes (here type-I ELMs) in magnetically confined fusion plasmas can be mitigated or even suppressed by resonant magnetic perturbation fields. This observation opened up a possible scheme to avoid too large erosion and material damage by such transients in future fusion devices such as ITER. However, it is widely recognized that a more basic understanding is needed to extrapolate the results obtained in present experiments to future fusion devices. The 4th workshop on Stochasticity in Fusion Plasmas was held in Jülich, Germany, from 2 to 4 March 2009. This series of workshops aims at gathering fusion experts from various plasma configurations such as tokamaks, stellarators and reversed field pinches to exchange knowledge on structure formation and transport in stochastic fusion plasmas. The workshops have attracted colleagues from both experiment and theory and stimulated fruitful discussions about the basics of stochastic fusion plasmas. Important papers from the first three workshops in 2003, 2005 and 2007 have been published in previous special issues of Nuclear Fusion (stacks.iop.org/NF/44/i=6, stacks.iop.org/NF/46/i=4 and stacks.iop.org/NF/48/i=2). This special issue comprises contributions presented at the 4th SFP workshop, dealing with the main subjects such as formation of stochastic magnetic layers, energy and particle transport in stochastic magnetic fields, plasma response to external, non-axis-symmetric perturbations and last but not least application of resonant magnetic perturbations for

  16. Inertial fusion energy; L'energie de fusion inertielle

    Energy Technology Data Exchange (ETDEWEB)

    Decroisette, M.; Andre, M.; Bayer, C.; Juraszek, D. [CEA Bruyeres-le-Chatel, Dir. des Systemes d' Information (CEA/DIF), 91 (France); Le Garrec, B. [CEA Centre d' Etudes Scientifiques et Techniques d' Aquitaine, 33 - Le Barp (France); Deutsch, C. [Paris-11 Univ., 91 - Orsay (France); Migus, A. [Institut d' Optique Centre scientifique, 91 - Orsay (France)

    2005-07-01

    We first recall the scientific basis of inertial fusion and then describe a generic fusion reactor with the different components: the driver, the fusion chamber, the material treatment unit, the target factory and the turbines. We analyse the options proposed at the present time for the driver and for target irradiation scheme giving the state of art for each approach. We conclude by the presentation of LMJ (laser Megajoule) and NIF (national ignition facility) projects. These facilities aim to demonstrate the feasibility of laboratory DT ignition, first step toward Inertial Fusion Energy. (authors)

  17. Magnetic fusion energy plasma interactive and high heat flux components. Volume II. Technical assessment of the critical issues and problem areas in high heat flux materials and component development

    Energy Technology Data Exchange (ETDEWEB)

    Abdou, M.A.; Boyd, R.D.; Easor, J.R.; Gauster, W.B.; Gordon, J.D.; Mattas, R.F.; Morgan, G.D.; Ulrickson, M.A,; Watson, R.D.; Wolfer, W.G,

    1984-06-01

    A technical assessment of the critical issues and problem areas for high heat flux materials and components (HHFMC) in magnetic fusion devices shows these problems to be of critical importance for the successful operation of near-term fusion experiments and for the feasibility and attractiveness of long-term fusion reactors. A number of subgroups were formed to assess the critical HHFMC issues along the following major lines: (1) source conditions, (2) systems integration, (3) materials and processes, (4) thermal hydraulics, (5) thermomechanical response, (6) electromagnetic response, (7) instrumentation and control, and (8) test facilities. The details of the technical assessment are presented in eight chapters. The primary technical issues and needs for each area are highlighted.

  18. Multiparametric Magnetic Resonance Imaging (MRI) and MRI-Transrectal Ultrasound Fusion Biopsy for Index Tumor Detection: Correlation with Radical Prostatectomy Specimen.

    Science.gov (United States)

    Radtke, Jan P; Schwab, Constantin; Wolf, Maya B; Freitag, Martin T; Alt, Celine D; Kesch, Claudia; Popeneciu, Ionel V; Huettenbrink, Clemens; Gasch, Claudia; Klein, Tilman; Bonekamp, David; Duensing, Stefan; Roth, Wilfried; Schueler, Svenja; Stock, Christian; Schlemmer, Heinz-Peter; Roethke, Matthias; Hohenfellner, Markus; Hadaschik, Boris A

    2016-11-01

    Multiparametric magnetic resonance imaging (mpMRI) and MRI fusion targeted biopsy (FTB) detect significant prostate cancer (sPCa) more accurately than conventional biopsies alone. To evaluate the detection accuracy of mpMRI and FTB on radical prostatectomy (RP) specimen. From a cohort of 755 men who underwent transperineal MRI and transrectal ultrasound fusion biopsy under general anesthesia between 2012 and 2014, we retrospectively analyzed 120 consecutive patients who had subsequent RP. All received saturation biopsy (SB) in addition to FTB of lesions with Prostate Imaging Reporting and Data System (PI-RADS) score ≥2. The index lesion was defined as the lesion with extraprostatic extension, the highest Gleason score (GS), or the largest tumor volume (TV) if GS were the same, in order of priority. GS 3+3 and TV ≥1.3ml or GS ≥3+4 and TV ≥0.55ml were considered sPCa. We assessed the detection accuracy by mpMRI and different biopsy approaches and analyzed lesion agreement between mpMRI and RP specimen. Overall, 120 index and 71 nonindex lesions were detected. Overall, 107 (89%) index and 51 (72%) nonindex lesions harbored sPCa. MpMRI detected 110 of 120 (92%) index lesions, FTB (two cores per lesion) alone diagnosed 96 of 120 (80%) index lesions, and SB alone diagnosed 110 of 120 (92%) index lesions. Combined SB and FTB detected 115 of 120 (96%) index foci. FTB performed significantly less accurately compared with mpMRI (p=0.02) and the combination for index lesion detection (p=0.002). Combined FTB and SB detected 97% of all sPCa lesions and was superior to mpMRI (85%), FTB (79%), and SB (88%) alone (pcorrelation coefficient for index lesion agreement between mpMRI and RP was 0.87 (p<0.001). Limitations included the retrospective design, multiple operators, and nonblinding of radiologists. MpMRI identified 92% of index lesions compared with RP histopathology. The combination of FTB and SB was superior to both approaches alone, reliably detecting 97% of s

  19. Introduction to Nuclear Fusion Power and the Design of Fusion Reactors. An Issue-Oriented Module.

    Science.gov (United States)

    Fillo, J. A.

    This three-part module focuses on the principles of nuclear fusion and on the likely nature and components of a controlled-fusion power reactor. The physical conditions for a net energy release from fusion and two approaches (magnetic and inertial confinement) which are being developed to achieve this goal are described. Safety issues associated…

  20. Introduction to Nuclear Fusion Power and the Design of Fusion Reactors. An Issue-Oriented Module.

    Science.gov (United States)

    Fillo, J. A.

    This three-part module focuses on the principles of nuclear fusion and on the likely nature and components of a controlled-fusion power reactor. The physical conditions for a net energy release from fusion and two approaches (magnetic and inertial confinement) which are being developed to achieve this goal are described. Safety issues associated…

  1. Variations in data collection methods between national databases affect study results: a comparison of the nationwide inpatient sample and national surgical quality improvement program databases for lumbar spine fusion procedures.

    Science.gov (United States)

    Bohl, Daniel D; Russo, Glenn S; Basques, Bryce A; Golinvaux, Nicholas S; Fu, Michael C; Long, William D; Grauer, Jonathan N

    2014-12-03

    There has been an increasing use of national databases to conduct orthopaedic research. Questions regarding the validity and consistency of these studies have not been fully addressed. The purpose of this study was to test for similarity in reported measures between two national databases commonly used for orthopaedic research. A retrospective cohort study of patients undergoing lumbar spinal fusion procedures during 2009 to 2011 was performed in two national databases: the Nationwide Inpatient Sample and the National Surgical Quality Improvement Program. Demographic characteristics, comorbidities, and inpatient adverse events were directly compared between databases. The total numbers of patients included were 144,098 from the Nationwide Inpatient Sample and 8434 from the National Surgical Quality Improvement Program. There were only small differences in demographic characteristics between the two databases. There were large differences between databases in the rates at which specific comorbidities were documented. Non-morbid obesity was documented at rates of 9.33% in the Nationwide Inpatient Sample and 36.93% in the National Surgical Quality Improvement Program (relative risk, 0.25; p databases in the rates at which specific inpatient adverse events were documented. Sepsis was documented at rates of 0.38% in the Nationwide Inpatient Sample and 0.81% in the National Surgical Quality Improvement Program (relative risk, 0.47; p database studies become more prevalent in orthopaedic surgery, authors, reviewers, and readers should view these studies with caution. This study shows that two commonly used databases can identify demographically similar patients undergoing a common orthopaedic procedure; however, the databases document markedly different rates of comorbidities and inpatient adverse events. The differences are likely the result of the very different mechanisms through which the databases collect their comorbidity and adverse event data. Findings highlight

  2. Lhermitte-Duclos disease presenting with positron emission tomography-magnetic resonance fusion imaging: a case report

    Directory of Open Access Journals (Sweden)

    Calabria Ferdinando

    2012-03-01

    Full Text Available Abstract Introduction Lhermitte-Duclos disease or dysplastic gangliocytoma of the cerebellum is an extremely rare tumor. It is a slowly enlarging mass within the cerebellar cortex. The majority of cases are diagnosed in the third or fourth decade of life. Case presentation We report the case of a 37-year-old Caucasian woman who underwent positron emission tomography-computed tomography with fluorine-18-fluorodeoxyglucose for evaluation of a solitary lung node. No pathological uptake was detected in the solitary lung node but the positron emission tomography-computed tomography of her brain showed intense tracer uptake, suggestive of a malignant neoplasm, in a mass in her left cerebellar lobe. Our patient had experienced two years of occipital headache and movement disorder. Subsequently, magnetic resonance imaging was performed with contrast agent administration, showing a large subtentorial mass in her left cerebellar hemisphere, with compression and dislocation of the fourth ventricle. Metabolic data provided by positron emission tomography and morphological magnetic resonance imaging views were fused in post-processing, allowing a diagnosis of dysplastic gangliocytoma with increased glucose metabolism. Total resection of the tumor was performed and histological examination confirmed the diagnosis of Lhermitte-Duclos disease. Conclusions Our case indicates that increased uptake of fluorine-18-fluorodeoxyglucose may be misinterpreted as a neoplastic process in the evaluation of patients with Lhermitte-Duclos disease, but supports the usefulness of integrated positron emission tomography-magnetic resonance imaging in the exact pathophysiologic explanation of this disease and in making the correct diagnosis. However, an accurate physical examination and exact knowledge of clinical data is of the utmost importance.

  3. Peaceful Uses of Fusion

    Science.gov (United States)

    Teller, E.

    1958-07-03

    Applications of thermonuclear energy for peaceful and constructive purposes are surveyed. Developments and problems in the release and control of fusion energy are reviewed. It is pointed out that the future of thermonuclear power reactors will depend upon the construction of a machine that produces more electric energy than it consumes. The fuel for thermonuclear reactors is cheap and practically inexhaustible. Thermonuclear reactors produce less dangerous radioactive materials than fission reactors and, when once brought under control, are not as likely to be subject to dangerous excursions. The interaction of the hot plasma with magnetic fields opens the way for the direct production of electricity. It is possible that explosive fusion energy released underground may be harnessed for the production of electricity before the same feat is accomplished in controlled fusion processes. Applications of underground detonations of fission devices in mining and for the enhancement of oil flow in large low-specific-yield formations are also suggested.

  4. Aneutronic Fusion Spacecraft Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Description: provide framework to realize fusion propulsion for long-range space travel; analyze “hybrid” schemes with a solar or fission primary energy...

  5. Aerial radiometric and magnetic survey: Death Valley National Topographic Map, Nevada, California

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-17

    The results of analysis of the airborne gamma radiation survey flown for the region identified as the Death Valley National Topographic Map NJ11-11 is presented in the bound Volume of this report. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlated as a function of geologic units. The distribution of data within each geologic unit, for all surveyed map lines and tie lines, has been calculated and is included. Two sets of profiled data for each line are included with one set displaying the above-cited data. The second set includes only flight line magnetic field, temperature, pressure, altitude data plus magnetic field data as measured at a base station. A general description of the area, including descriptions of the various geologic units and the corresponding airborne data, is included also.

  6. Construction and operation of parallel electric and magnetic field spectrometers for mass/energy resolved multi-ion charge exchange diagnostics on the Tokamak Fusion Test Reactor

    Science.gov (United States)

    Medley, S. S.; Roquemore, A. L.

    1998-07-01

    A novel charge exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory for neutral particle diagnostics on the Tokamak Fusion Test Reactor (TFTR). The E∥B spectrometer has an energy range of 0.5⩽A (amu)E (keV)⩽600 and provides mass-resolved energy spectra of H+, D+, and T+ (or 3He+) ion species simultaneously during a single discharge. The detector plane exhibits parallel rows of analyzed ions, each row containing the energy dispersed ions of a given mass-to-charge ratio. The detector consists of a large area microchannel plate (MCP) which is provided with three rectangular, semicontinuous active area strips, one coinciding with each of the mass rows for detection of H+, D+, and T+ (or 3He+) and each mass row has 75 energy channels. To suppress spurious signals attending operation of the plate in the magnetic fringe field of the spectrometer, the MCP was housed in a double-walled iron shield with a wire mesh ion entrance window. Using an accelerator neutron generator, the MCP neutron detection efficiency was measured to be 1.7×10-3 and 6.4×10-3 counts/neutron/cm2 for 2.5 MeV-DD and 14 MeV-DT neutrons, respectively. The design and calibration of the spectrometer are described in detail, including the effect of MCP exposure to tritium, and results obtained during high performance D-D operation on TFTR are presented to illustrate the performance of the E∥B spectrometer. The spectrometers were not used during D-T plasma operation due to the cost of providing the required radiation shielding.

  7. Experimental validation of Mueller-Stokes theory and investigation of the influence of the Cotton-Mouton effect on polarimetry in a magnetized fusion plasma

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Peebles, W. A.; Crocker, N. A.; Carter, T. A.; Doyle, E. J.; Rhodes, T. L.; Wang, G.; Zeng, L. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-7099 (United States); Hyatt, A. W. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

    2013-10-15

    Mueller-Stokes theory can be used to calculate the polarization evolution of an electromagnetic (EM) wave as it propagates through a magnetized plasma. Historically, the theory has been used to interpret polarimeter signals from systems operating on fusion plasmas. These interpretations have mostly employed approximations of Mueller-Stokes theory in regimes where either the Faraday rotation (FR) or the Cotton-Mouton (CM) effect is dominant. The current paper presents the first systematic comparison of polarimeter measurements with the predictions of full Mueller-Stokes theory where conditions transition smoothly from a FR-dominant (i.e., weak CM effect) plasma to one where the CM effect plays a significant role. A synthetic diagnostic code, based on Mueller-Stokes theory accurately reproduces the trends evident in the experimentally measured polarimeter phase over this entire operating range, thereby validating Mueller-Stokes theory. The synthetic diagnostic code is then used to investigate the influence of the CM effect on polarimetry measurements. As expected, the measurements are well approximated by the FR effect when the CM effect is predicted to be weak. However, the code shows that as the CM effect increases, it can compete with the FR effect in rotating the polarization of the EM-wave. This results in a reduced polarimeter response to the FR effect, just as observed in the experiment. The code also shows if sufficiently large, the CM effect can even reverse the handedness of a wave launched with circular polarization. This helps to understand the surprising experimental observations that the sensitivity to the FR effect can be nearly eliminated at high enough B{sub T} (2.0 T). The results also suggest that the CM effect on the plasma midplane can be exploited to potentially measure magnetic shear in tokamak plasmas. These results establish increased confidence in the use of such a synthetic diagnostic code to guide future polarimetry design and interpret

  8. ORNL integral experiment to provide data for evaluating magnetic-fusion-energy shielding concepts. Part I. Attenuation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, G.T.; Morgan, G.L.; McConnell, J.W.

    1982-08-01

    Integral experiments to measure the energy spectra of neutrons and gamma rays due to the transport of approximately 14-MeV T(d,n)/sup 4/He neutrons through laminated stainless steel and borated-polyethylene shield configurations have been performed at the Oak Ridge National Laboratory. An NE-213 detector and conventional pulse-shape-discrimination circuitry were used to record the pulse-height distributions from which the energy spectra were derived. Descriptions of the facility and experimental techniques are given in this paper along with tables and curves showing the results of the measurements.

  9. Generomak: Fusion physics, engineering and costing model

    Energy Technology Data Exchange (ETDEWEB)

    Delene, J.G.; Krakowski, R.A.; Sheffield, J.; Dory, R.A.

    1988-06-01

    A generic fusion physics, engineering and economics model (Generomak) was developed as a means of performing consistent analysis of the economic viability of alternative magnetic fusion reactors. The original Generomak model developed at Oak Ridge by Sheffield was expanded for the analyses of the Senior Committee on Environmental Safety and Economics of Magnetic Fusion Energy (ESECOM). This report describes the Generomak code as used by ESECOM. The input data used for each of the ten ESECOM fusion plants and the Generomak code output for each case is given. 14 refs., 3 figs., 17 tabs.

  10. Advanced fusion concepts: project summaries

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-12-01

    This report contains descriptions of the activities of all the projects supported by the Advanced Fusion Concepts Branch of the Office of Fusion Energy, US Department of Energy. These descriptions are project summaries of each of the individual projects, and contain the following: title, principle investigators, funding levels, purpose, approach, progress, plans, milestones, graduate students, graduates, other professional staff, and recent publications. Information is given for each of the following programs: (1) reverse-field pinch, (2) compact toroid, (3) alternate fuel/multipoles, (4) stellarator/torsatron, (5) linear magnetic fusion, (6) liners, and (7) Tormac. (MOW)

  11. Magnetic Reconnection

    NARCIS (Netherlands)

    Schep, T. J.

    1994-01-01

    This lecture deals with the concept of magnetic field lines and with the conservation of magnetic flux. In high temperature fusion devices like tokamaks flux conservation can be violated and reconnection can occur at closed magnetic field lines. Reconnection processes lead to changes in the global t

  12. Magnetic susceptibility measurements in Yellowstone National Park, USA; Beikoku Yellowstone kokuritsu koen ni okeru genchi jikaritsu sokutei

    Energy Technology Data Exchange (ETDEWEB)

    Okuma, S. [Geological Survey of Japan, Tsukuba (Japan)

    1997-05-27

    For the purpose of interpreting data of the aeromagnetic anomalies in Yellowstone National Park in the U.S.A., in-situ magnetization intensity measurements have been carried out in 1994 and 1995 on geological outcrops of rocks in that area. Comparisons and discussions were given on the measurement results, and existing rock magnetic data and aeromagnetic anomaly data available for the area. Outside the Yellowstone caldera, part of granitic gneisses among the Precambrian granitic gneisses and crystalline schists distributed to the north has an abnormally high magnetization intensity of 1 {times} 10 {sup -2} SI. This could be a powerful anomaly source for the high magnetic anomaly in this area. Paleogene volcanic rocks distributed widely in the eastern part of the park also have magnetization intensity as high as 1 {times} 10 {sup -2} SI or higher, which are also thought a powerful anomaly source in this area. Part of Pleistocene basalts which are exposed partially in the western part of the park has also very high magnetization intensity at 1 {times} 10 {sup -2} SI or higher. This suggests correlation with the magnetic anomaly in the east-west direction distributed in this area. Quaternary rhyolites are more magnetic than Quaternary welded tuffs, which should give greater effects to the magnetic anomaly. 10 refs., 5 figs.

  13. Fusion Safety Program Annual Report, Fiscal Year 1996

    Energy Technology Data Exchange (ETDEWEB)

    Longhurst, G.R.; Anderl, R.A.; Cadwallader, L.C. [and others

    1996-12-01

    This report summarizes the major activities of the Fusion Safety Program in FY 1996. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory, and Lockheed Martin Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. The objective is to perform research and develop data needed to ensure safety in fusion facilities. Activities include experiments, analysis, code development and application, and other forms of research. These activities are conducted at the INEL, at other DOE laboratories, and at other institutions. Among the technical areas covered in this report are tritium safety, chemical reactions and activation product release, risk assessment failure rate database development, and safety code development and application to fusion safety issues. Most of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Work done for ITER this year has focused on developing the needed information for the Non- Site- Specific Safety Report (NSSR-1). A final area of activity described is development of the new DOE Technical Standards for Safety of Magnetic Fusion Facilities.

  14. Cold fusion

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Suk Yong; Sung, Ki Woong; Kang, Joo Sang; Lee, Jong Jik [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    So called `cold fusion phenomena` are not confirmed yet. Excess heat generation is very delicate one. Neutron generation is most reliable results, however, the records are erratic and the same results could not be repeated. So there is no reason to exclude the malfunction of testing instruments. The same arguments arise in recording {sup 4}He, {sup 3}He, {sup 3}H, which are not rich in quantity basically. An experiment where plenty of {sup 4}He were recorded is attached in appendix. The problem is that we are trying to search cold fusion which is permitted by nature or not. The famous tunneling effect in quantum mechanics will answer it, however, the most fusion rate is known to be negligible. The focus of this project is on the theme that how to increase that negligible fusion rate. 6 figs, 4 tabs, 1512 refs. (Author).

  15. Spinal Fusion

    Science.gov (United States)

    ... results in predictable healing. Autograft is currently the “gold standard” source of bone for a fusion. The ... pump. With this technique, the patient presses a button that delivers a predetermined amount of narcotic pain ...

  16. Accelerator and Fusion Research Division. Annual report, October 1977--September 1978

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    Research is reported for the combined groups consisting of the Accelerator Division and the Magnetic Fusion Energy Group. Major topics reported include accelerator operations, magnetic fusion energy, and advanced accelerator development. (GHT)

  17. Extraction of the spatial distribution of electron temperature and density in Magnetized Liner Inertial Fusion implosion plasmas

    Science.gov (United States)

    Carpenter, Kyle; Mancini, Roberto

    2016-10-01

    We are testing polychromatic tomography to extract the spatial distribution of electron temperatures and densities in the cylindrical implosion plasmas created during MagLIF. Motivation for this technique stems from its successful application to spherical implosion core plasmas on Omega through the analysis of spatially resolved spectra (SRS) collected via pinhole imaging. In MagLIF, collections of SRS can be extracted from the images created by the slit imaging CRITR spectrometers. These spectra can be complemented with pinhole monochromatic images and spectra recorded with a spherical crystal spectrometer. One axially resolved and one radially resolved CRITR are field during MagLIF and information extracted from one of these SRS would be spatially integrated over a plane of finite thickness given by the spatial resolution of the instrument. In our method, we couple a model that creates synthetic sets of spectra, like those obtained from an experiment, with a Pareto genetic algorithm which searches in parameter space for the spatial distribution which best simultaneously and self-consistently fits the set of SRS/ Solutions obtained are used as the initial solution for a Levenberg-Marquadt minimization algorithm to provide a final ``fine-tuned'' solution. We are testing this method by creating synthetic ``experimental'' data and using the technique to search for the spatial distribution. The results of these feasibility studies will be discussed. The work is supported by a contract from Sandia National Laboratories.

  18. Intense fusion neutron sources

    Science.gov (United States)

    Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

    2010-04-01

    The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

  19. Performance metrics for Inertial Confinement Fusion implosions: aspects of the technical framework for measuring progress in the National Ignition Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Spears, B K; Glenzer, S; Edwards, M J; Brandon, S; Clark, D; Town, R; Cerjan, C; Dylla-Spears, R; Mapoles, E; Munro, D; Salmonson, J; Sepke, S; Weber, S; Hatchett, S; Haan, S; Springer, P; Moses, E; Mapoles, E; Munro, D; Salmonson, J; Sepke, S

    2011-12-16

    The National Ignition Campaign (NIC) uses non-igniting 'THD' capsules to study and optimize the hydrodynamic assembly of the fuel without burn. These capsules are designed to simultaneously reduce DT neutron yield and to maintain hydrodynamic similarity with the DT ignition capsule. We will discuss nominal THD performance and the associated experimental observables. We will show the results of large ensembles of numerical simulations of THD and DT implosions and their simulated diagnostic outputs. These simulations cover a broad range of both nominal and off nominal implosions. We will focus on the development of an experimental implosion performance metric called the experimental ignition threshold factor (ITFX). We will discuss the relationship between ITFX and other integrated performance metrics, including the ignition threshold factor (ITF), the generalized Lawson criterion (GLC), and the hot spot pressure (HSP). We will then consider the experimental results of the recent NIC THD campaign. We will show that we can observe the key quantities for producing a measured ITFX and for inferring the other performance metrics. We will discuss trends in the experimental data, improvement in ITFX, and briefly the upcoming tuning campaign aimed at taking the next steps in performance improvement on the path to ignition on NIF.

  20. EDITORIAL: The Nuclear Fusion Award The Nuclear Fusion Award

    Science.gov (United States)

    Kikuchi, M.

    2011-01-01

    The Nuclear Fusion Award ceremony for 2009 and 2010 award winners was held during the 23rd IAEA Fusion Energy Conference in Daejeon. This time, both 2009 and 2010 award winners were celebrated by the IAEA and the participants of the 23rd IAEA Fusion Energy Conference. The Nuclear Fusion Award is a paper prize to acknowledge the best distinguished paper among the published papers in a particular volume of the Nuclear Fusion journal. Among the top-cited and highly-recommended papers chosen by the Editorial Board, excluding overview and review papers, and by analyzing self-citation and non-self-citation with an emphasis on non-self-citation, the Editorial Board confidentially selects ten distinguished papers as nominees for the Nuclear Fusion Award. Certificates are given to the leading authors of the Nuclear Fusion Award nominees. The final winner is selected among the ten nominees by the Nuclear Fusion Editorial Board voting confidentially. 2009 Nuclear Fusion Award nominees For the 2009 award, the papers published in the 2006 volume were assessed and the following papers were nominated, most of which are magnetic confinement experiments, theory and modeling, while one addresses inertial confinement. Sabbagh S.A. et al 2006 Resistive wall stabilized operation in rotating high beta NSTX plasmas Nucl. Fusion 46 635-44 La Haye R.J. et al 2006 Cross-machine benchmarking for ITER of neoclassical tearing mode stabilization by electron cyclotron current drive Nucl. Fusion 46 451-61 Honrubia J.J. et al 2006 Three-dimensional fast electron transport for ignition-scale inertial fusion capsules Nucl. Fusion 46 L25-8 Ido T. et al 2006 Observation of the interaction between the geodesic acoustic mode and ambient fluctuation in the JFT-2M tokamak Nucl. Fusion 46 512-20 Plyusnin V.V. et al 2006 Study of runaway electron generation during major disruptions in JET Nucl. Fusion 46 277-84 Pitts R.A. et al 2006 Far SOL ELM ion energies in JET Nucl. Fusion 46 82-98 Berk H.L. et al 2006

  1. Scientific and Computational Challenges of the Fusion Simulation Program (FSP)

    Energy Technology Data Exchange (ETDEWEB)

    William M. Tang

    2011-02-09

    This paper highlights the scientific and computational challenges facing the Fusion Simulation Program (FSP) a major national initiative in the United States with the primary objective being to enable scientific discovery of important new plasma phenomena with associated understanding that emerges only upon integration. This requires developing a predictive integrated simulation capability for magnetically-confined fusion plasmas that are properly validated against experiments in regimes relevant for producing practical fusion energy. It is expected to provide a suite of advanced modeling tools for reliably predicting fusion device behavior with comprehensive and targeted science-based simulations of nonlinearly-coupled phenomena in the core plasma, edge plasma, and wall region on time and space scales required for fusion energy production. As such, it will strive to embody the most current theoretical and experimental understanding of magnetic fusion plasmas and to provide a living framework for the simulation of such plasmas as the associated physics understanding continues to advance over the next several decades. Substantive progress on answering the outstanding scientific questions in the field will drive the FSP toward its ultimate goal of developing the ability to predict the behavior of plasma discharges in toroidal magnetic fusion devices with high physics fidelity on all relevant time and space scales. From a computational perspective, this will demand computing resources in the petascale range and beyond together with the associated multi-core algorithmic formulation needed to address burning plasma issues relevant to ITER - a multibillion dollar collaborative experiment involving seven international partners representing over half the world's population. Even more powerful exascale platforms will be needed to meet the future challenges of designing a demonstration fusion reactor (DEMO). Analogous to other major applied physics modeling projects (e

  2. Fusion - 2050 perspective (in Polish)

    CERN Document Server

    Romaniuk, R S

    2013-01-01

    The results of strongly exothermic reaction of thermonuclear fusion between nuclei of deuterium and tritium are: helium nuclei and neutrons, plus considerable kinetic energy of neutrons of over 14 MeV. DT nuclides synthesis reaction is probably not the most favorable one for energy production, but is the most advanced technologically. More efficient would be possibly aneutronic fusion. The EU by its EURATOM agenda prepared a Road Map for research and implementation of Fusion as a commercial method of thermonuclear energy generation in the time horizon of 2050.The milestones on this road are tokomak experiments JET, ITER and DEMO, and neutron experiment IFMIF. There is a hope, that by engagement of the national government, and all research and technical fusion communities, part of this Road Map may be realized in Poland. The infrastructure build for fusion experiments may be also used for material engineering research, chemistry, biomedical, associated with environment protection, power engineering, security, ...

  3. Laser-fusion rocket for interplanetary propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R.A.

    1983-09-27

    A rocket powered by fusion microexplosions is well suited for quick interplanetary travel. Fusion pellets are sequentially injected into a magnetic thrust chamber. There, focused energy from a fusion Driver is used to implode and ignite them. Upon exploding, the plasma debris expands into the surrounding magnetic field and is redirected by it, producing thrust. This paper discusses the desired features and operation of the fusion pellet, its Driver, and magnetic thrust chamber. A rocket design is presented which uses slightly tritium-enriched deuterium as the fusion fuel, a high temperature KrF laser as the Driver, and a thrust chamber consisting of a single superconducting current loop protected from the pellet by a radiation shield. This rocket can be operated with a power-to-mass ratio of 110 W gm/sup -1/, which permits missions ranging from occasional 9 day VIP service to Mars, to routine 1 year, 1500 ton, Plutonian cargo runs.

  4. Plasma Physics and Controlled Nuclear Fusion

    Science.gov (United States)

    Fisch, N. J.

    2010-01-01

    Already while making his famous contributions in uncontrolled nuclear fusion for wartime uses, Edward Teller contemplated how the abundant energy release through nuclear fusion might serve peacetime uses as well. His legacy in controlled nuclear fusion, and the associated physics of plasmas, spans both magnetic and inertial confinement approaches. His contributions in plasma physics, both the intellectual and the administrative, continue to impact the field.

  5. Trophoblast fusion.

    Science.gov (United States)

    Huppertz, Berthold; Gauster, Martin

    2011-01-01

    The villous trophoblast of the human placenta is the epithelial cover of the fetal chorionic villi floating in maternal blood. This epithelial cover is organized in two distinct layers, the multinucleated syncytiotrophoblast directly facing maternal blood and a second layer of mononucleated cytotrophoblasts. During pregnancy single cytotrophoblasts continuously fuse with the overlying syncytiotrophoblast to preserve this end-differentiated layer until delivery. Syncytial fusion continuously supplies the syncytiotrophoblast with compounds of fusing cytotrophoblasts such as proteins, nucleic acids and lipids as well as organelles. At the same time the input of cytotrophoblastic components is counterbalanced by a continuous release of apoptotic material from the syncytiotrophoblast into maternal blood. Fusion is an essential step in maintaining the syncytiotrophoblast. Trophoblast fusion was shown to be dependant on and regulated by multiple factors such as fusion proteins, proteases and cytoskeletal proteins as well as cytokines, hormones and transcription factors. In this chapter we focus on factors that may be involved in the fusion process of trophoblast directly or that may prepare the cytotrophoblast to fuse.

  6. Laser fusion monthly -- August 1980

    Energy Technology Data Exchange (ETDEWEB)

    Ahlstrom, H.G. [ed.

    1980-08-01

    This report documents the monthly progress for the laser fusion research at Lawrence Livermore National Laboratory. First it gives facilities report for both the Shiva and Argus projects. Topics discussed include; laser system for the Nova Project; the fusion experiments analysis facility; optical/x-ray streak camera; Shiva Dante System temporal response; 2{omega}{sub 0} experiment; and planning for an ICF engineering test facility.

  7. Design and Characterization of a Neutralized-Transport Experiment for Heavy-Ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, E; Eylon, S; Roy, P; Yu, S S; Anders, A; Bieniosek, F M; Greenway, W G; Logan, B G; MacGill, R A; Shuman, D B; Vanecek, D L; Waldron, W L; Sharp, W M; Houck, T L; Davidson, R C; Efthimion, P C; Gilson, E P; Sefkow, A B; Welch, D R; Rose, D V; Olson, C L

    2004-05-24

    In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparisons of theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion Fusion has completed the construction and has begun experimentation with the Neutralized Transport Experiment (NTX). The experiment consists of three main sections, each with its own physics issues. The injector is designed to generate a very high-brightness, space-charge-dominated potassium beam while still allowing variable perveance by a beam aperturing technique. The magnetic-focusing section, consisting of four pulsed magnetic quadrupoles, permits the study of beam tuning, as well as the effects of phase space dilution due to higher-order nonlinear fields. In the final section, a converging ion beam exiting the magnetic section is transported through a drift region with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this paper, we discuss the design and characterization of the three sections in detail and present the first results from the experiment.

  8. Design and characterization of a neutralized-transport experiment for heavy-ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Henestroza, E.; Eylon, S.; Roy, P.K.; Yu, S.S.; Anders, A.; Bieniosek, F.M.; Greenway, W.G.; Logan, B.G.; MacGill, R.A.; Shuman, D.B.; Vanecek, D.L.; Waldron, W.L.; Sharp, W.M.; Houck, T.L.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Sefkow, A.B.; Welch, D.R.; Rose, D.V.; Olson, C.L.

    2004-03-14

    In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparisons of theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion Fusion has completed the construction and has begun experimentation with the Neutralized Transport Experiment (NTX). The experiment consists of three main sections, each with its own physics issues. The injector is designed to generate a very high-brightness, space-charge-dominated potassium beam while still allowing variable perveance by a beam aperturing technique. The magnetic-focusing section, consisting of four pulsed magnetic quadrupoles, permits the study of beam tuning, as well as the effects of phase space dilution due to higher-order nonlinear fields. In the final section, the converging ion beam exiting the magnetic section is transported through a drift region with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this paper, we discuss the design and characterization of the three sections in detail and present initial results from the experiment.

  9. Fusion Machinery

    DEFF Research Database (Denmark)

    Sørensen, Jakob Balslev; Milosevic, Ira

    2015-01-01

    the vesicular SNARE VAMP2/synaptobrevin-2 and the target (plasma membrane) SNAREs SNAP25 and syntaxin-1 results in fusion and release of neurotransmitter, synchronized to the electrical activity of the cell by calcium influx and binding to synaptotagmin. Formation of the SNARE complex is tightly regulated...... and appears to start with syntaxin-1 bound to an SM (Sec1/Munc18-like) protein. Proteins of the Munc13-family are responsible for opening up syntaxin and allowing sequential binding of SNAP-25 and VAMP2/synaptobrevin-2. N- to C-terminal “zippering” of the SNARE domains leads to membrane fusion...

  10. Magnetic resonance imaging-targeted, 3D transrectal ultrasound-guided fusion biopsy for prostate cancer: Quantifying the impact of needle delivery error on diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Peter R., E-mail: pmarti46@uwo.ca [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Cool, Derek W. [Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7, Canada and Robarts Research Institute, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Romagnoli, Cesare [Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Fenster, Aaron [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Robarts Research Institute, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Ward, Aaron D. [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2014-07-15

    Purpose: Magnetic resonance imaging (MRI)-targeted, 3D transrectal ultrasound (TRUS)-guided “fusion” prostate biopsy intends to reduce the ∼23% false negative rate of clinical two-dimensional TRUS-guided sextant biopsy. Although it has been reported to double the positive yield, MRI-targeted biopsies continue to yield false negatives. Therefore, the authors propose to investigate how biopsy system needle delivery error affects the probability of sampling each tumor, by accounting for uncertainties due to guidance system error, image registration error, and irregular tumor shapes. Methods: T2-weighted, dynamic contrast-enhanced T1-weighted, and diffusion-weighted prostate MRI and 3D TRUS images were obtained from 49 patients. A radiologist and radiology resident contoured 81 suspicious regions, yielding 3D tumor surfaces that were registered to the 3D TRUS images using an iterative closest point prostate surface-based method to yield 3D binary images of the suspicious regions in the TRUS context. The probabilityP of obtaining a sample of tumor tissue in one biopsy core was calculated by integrating a 3D Gaussian distribution over each suspicious region domain. Next, the authors performed an exhaustive search to determine the maximum root mean squared error (RMSE, in mm) of a biopsy system that gives P ≥ 95% for each tumor sample, and then repeated this procedure for equal-volume spheres corresponding to each tumor sample. Finally, the authors investigated the effect of probe-axis-direction error on measured tumor burden by studying the relationship between the error and estimated percentage of core involvement. Results: Given a 3.5 mm RMSE for contemporary fusion biopsy systems,P ≥ 95% for 21 out of 81 tumors. The authors determined that for a biopsy system with 3.5 mm RMSE, one cannot expect to sample tumors of approximately 1 cm{sup 3} or smaller with 95% probability with only one biopsy core. The predicted maximum RMSE giving P ≥ 95% for each

  11. Gasdynamic Mirror (GDM) Fusion Propulsion Engine Experiment

    Science.gov (United States)

    1999-01-01

    The Gasdynamic Mirror, or GDM, is an example of a magnetic mirror-based fusion propulsion system. Its design is primarily consisting of a long slender solenoid surrounding a vacuum chamber that contains plasma. The bulk of the fusion plasma is confined by magnetic field generated by a series of toroidal-shaped magnets in the center section of the device. the purpose of the GDM Fusion Propulsion Experiment is to confirm the feasibility of the concept and to demonstrate many of the operational characteristics of a full-size plasma can be confined within the desired physical configuration and still reman stable. This image shows an engineer from Propulsion Research Technologies Division at Marshall Space Flight Center inspecting solenoid magnets-A, an integrate part of the Gasdynamic Mirror Fusion Propulsion Engine Experiment.

  12. Francis Bitter National Magnet Laboratory. Annual Report, July 1985-June 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Contents include: reports on laboratory research programs-- (quantum optics, magnetism, condensed matter chemistry, superconductivity, magnetic separation, magnetic fields of the brain, molecular biophysics, solid-state nuclear magnetic resonance, magnet technology, instrumentation for high-magnetic-field research); reports of visiting scientists-- (reports of users of the high-magnetic-field facility, reports of users of the pulsed-field facility, reports of users of the squid magnetometer and Moessbauer facility); appendices: (publications and meeting speeches, organization, summary of high-field magnet facility use January 1, 1981 through December 31, 1985, July 1, 1985 through June 30, 1986, geographic distribution of high-field magnet users (excluding laboratory staff), summary of educational activities); author index.

  13. New fusion method offers hope of new energy source

    CERN Multimedia

    Chang, K

    2002-01-01

    Scientists from Sandia National Laboratories have reported that they have acheived thermonuclear fusion using the Z accelerator. It is the first observation of fusion using a pulsed power source (1 page).

  14. Occupational exposure to magnetic fields and electric shocks and risk of ALS: the Swiss National Cohort.

    Science.gov (United States)

    Huss, Anke; Spoerri, Adrian; Egger, Matthias; Kromhout, Hans; Vermeulen, Roel

    2015-03-01

    Amyotrophic lateral sclerosis (ALS) has been associated with exposures in so-called 'electrical occupations'. It is unclear if this possible link may be explained by exposure to extremely low-frequency magnetic fields (ELF-MF) or by electrical shocks. We evaluated ALS mortality in 2000-2008 and exposure to ELF-MF and electrical shocks in the Swiss National Cohort, using job exposure matrices for occupations at censuses 1990 and 2000. We compared 2.2 million workers with high or medium vs. low exposure to ELF-MF and electrical shocks using Cox proportional hazard models. Results showed that mortality from ALS was higher in people who had medium or high ELF-MF exposure in both censuses (HR 1.55 (95% CI 1.11-2.15)), but closer to unity for electrical shocks (HR 1.17 (95% CI 0.83-1.65)). When both exposures were included in the same model, the HR for ELF-MF changed little (HR 1.56), but the HR for electric shocks was attenuated to 0.97. In conclusion, there was an association between exposure to ELF-MF and mortality from ALS among workers with a higher likelihood of long-term exposure.

  15. Accelerator and Fusion Research Division 1989 summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    This report discusses the research being conducted at Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division. The main topics covered are: heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; high-energy physics technology; and bevalac operations.

  16. Dipole magnet of synchrotron source for national synchrotron centre of Ukraine

    CERN Document Server

    Gladkikh, P I; Muratov, V I; Peev, F A

    2001-01-01

    The paper contains the revised design of a dipole magnet for a synchrotron radiation source.Usage of such a magnet allows to reach the energy of electrons in a ring up to 1.2 GeV.In paper the result of simulation of a magnet for all modes of operations of a source are shown.The proposed variant of the dipole magnet considerably raises parameters of the synchrotron radiation source.

  17. Fusion as a future energy source

    Science.gov (United States)

    Ward, D. J.

    2016-11-01

    Fusion remains the main source of energy generation in the Universe and is indirectly the origin of nearly all terrestrial energy (including fossil fuels) but it is the only fundamental energy source not used directly on Earth. Here we look at the characteristics of Earth-based fusion power, how it might contribute to future energy supply and what that tells us about the future direction of the R&D programme. The focus here is Magnetic Confinement Fusion although many of the points apply equally to inertial confinement fusion.

  18. Heavy ions offer a new approach to fusion

    CERN Document Server

    Celata, C M

    2002-01-01

    Three US laboratories have teamed up to form the Heavy-Ion Fusion Virtual National Laboratory to investigate a novel approach to fusion energy. The IBX is envisioned as a single-beam experiment, possibly upgradable to more beams, with final energy in the 10-20 MeV range. It will incorporate almost all of the physics of the driver (and much engineering at full scale), the exceptions being in the areas of beam-target physics, multiple-beam interactions and high-energy effects such as self-magnetic and inductive effects. In particular, the experiment will be able to study longitudinal beam dynamics, including wave motion on the beam, halo formation and beam heating over intermediate transport lengths, the bending of space-charge- dominated beams, and self-consistent final drift compression, final focus and neutralization.

  19. Fusion Safety Program annual report, fiscal year 1984

    Energy Technology Data Exchange (ETDEWEB)

    Crocker, J.G.; Holland, D.F.

    1985-06-01

    This report summarizes the Fusion Safety Program major activities in fiscal year 1984. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and EG and G Idaho, Inc., is the prime contractor for this program, which was initiated in 1979. A report section titled ''Activities at the INEL'' includes progress reports on the tritium implantation experiment, tritium blanket permeation, volatilization of reactor alloys, plasma disruptions, a comparative blanket safety assessment, transient code development, and a discussion of the INEL's participation in the Tokamak Fusion Core Experiment (TFCX) design study. The report section titled ''Outside Contracts'' includes progress reports on tritium conversion by the Oak Ridge National Laboratory (ORNL), lithium-lead reactions by the Hanford Engineering Development Laboratory (HEDL) and the University of Wisconsin, magnet safety by the Francis Bitter Magnet Laboratory of the Massachusetts Institute of Technology (MIT) and Argonne National Laboratory (ANL), risk assessment by MIT, tritium retention by the University of Virginia, and activation product release by GA Technologies. A list of publications produced during the year and brief descriptions of activities planned for FY-1985 are also included.

  20. Cold nuclear fusion reactor and nuclear fusion rocket

    Directory of Open Access Journals (Sweden)

    Huang Zhenqiang

    2013-10-01

    Full Text Available "Nuclear restraint inertial guidance directly hit the cold nuclear fusion reactor and ion speed dc transformer" [1], referred to as "cold fusion reactor" invention patents, Chinese Patent Application No. CN: 200910129632.7 [2]. The invention is characterized in that: at room temperature under vacuum conditions, specific combinations of the installation space of the electromagnetic field, based on light nuclei intrinsic magnetic moment and the electric field, the first two strings of the nuclei to be bound fusion on the same line (track of. Re-use nuclear spin angular momentum vector inherent nearly the speed of light to form a super strong spin rotation gyro inertial guidance features, to overcome the Coulomb repulsion strong bias barrier to achieve fusion directly hit. Similar constraints apply nuclear inertial guidance mode for different speeds and energy ion beam mixing speed, the design of ion speed dc transformer is cold fusion reactors, nuclear fusion engines and such nuclear power plants and power delivery systems start important supporting equipment, so apply for a patent merger

  1. Nuclear Fusion Award 2009 speech Nuclear Fusion Award 2009 speech

    Science.gov (United States)

    Sabbagh, Steven Anthony

    2011-01-01

    This is an exceptional moment in my career, and so I want to thank all of my teachers, colleagues and mentors who have made this possible. From my co-authors and myself, many thanks to the International Atomic Energy Agency, IOP Publishing, the Nuclear Fusion journal team, and the selection committee for the great honor of receiving this award. Also gratitude to Kikuchi-sensei, not only for the inventive and visionary creation of this award, but also for being a key mentor dating back to his efforts in producing high neutron output in JT-60U. It was also a great honor to receive the award directly from IAEA Deputy Director General Burkart during the 23rd IAEA Fusion Energy Conference in Daejeon. Receiving the award at this venue is particularly exciting as Daejeon is home to the new, next-generation KSTAR tokamak device that will lead key magnetic fusion research areas going forward. I would also like to thank the mayor of Daejeon, Dr Yum Hong-Chul, and all of the meeting organizers for giving us all a truly spectacular and singular welcoming event during which the award was presented. The research leading to the award would not have been possible without the support of the US Department of Energy, and I thank the Department for the continued funding of this research. Special mention must be made to a valuable co-author who is no longer with us, Professor A. Bondeson, who was a significant pioneer in resistive wall mode (RWM) research. I would like to thank my wife, Mary, for her infinite patience and encouragement. Finally, I would like to personally thank all of you that have approached and congratulated me directly. There are no units to measure how important your words have been in this regard. When notified that our paper had been shortlisted for the 2009 Nuclear Fusion Award, my co-authors responded echoing how I felt—honored to be included in such a fine collection of research by colleagues. It was unfathomable—would this paper follow the brilliant work

  2. 9. European fusion theory conference. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-10-01

    The aim of the conference was to provide a discussion forum covering all areas of magnetic fusion-oriented theoretical activities in Europe. The following main topics are included: multidimensional equilibria and operational limits; magnetic topology, macroinstabilities and magnetic reconnection; microinstabilities, turbulence, structures and transport processes; plasma rotation and radial electric fields; RF heating, current drive, helicity injection and non-resonant forces; plasma edge and divertor physics; computational modelling in magnetic fusion research. (LN)

  3. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    Science.gov (United States)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  4. Tame Fusion

    Institute of Scientific and Technical Information of China (English)

    S.D. Scott

    2003-01-01

    The first section of this paper covers preliminaries. Essentially, the next four cover units. It is shown that a compatible nearring with DCCR is Nnilpotent if and only if every maximal right N-subgroup is a right ideal. The last five sections relate to fusion (I.e., N-groups minimal for being generated by Nsubgroups, where each is N-isomorphic to a given N-group). Right N-subgroups of a tame nearring N with DCCR, minimal for not annihilating a minimal ideal from the left, are self monogenic and N-isomorphic. That this holds for any collection of minimal ideals is significant. Here, the right N-subgroup involved is a 'fusion product' of the 'components'.

  5. Measurements with magnetic field in the National Spherical Torus Experiment using the motional Stark effect with laser induced fluorescence diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Foley, E. L.; Levinton, F. M. [Nova Photonics, Inc., Princeton, New Jersey 08540 (United States)

    2013-04-15

    The motional Stark effect with laser-induced fluorescence diagnostic (MSE-LIF) has been installed and tested on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Lab. The MSE-LIF diagnostic will be capable of measuring radially resolved profiles of magnetic field magnitude or pitch angle in NSTX plasmas. The system includes a diagnostic neutral hydrogen beam and a laser which excites the n = 2 to n = 3 transition. A viewing system has been implemented which will support up to 38 channels from the plasma edge to past the magnetic axis. First measurements of MSE-LIF signals in the presence of small applied magnetic fields in neutral gas are reported.

  6. Carpal Fusion

    OpenAIRE

    2012-01-01

    Carpal fusion may be seen in hereditary and nonhereditary conditions such as acrocallosal syndrome,acromegaly, Apert syndrome, arthrogryposis, Carpenter syndrome, chromosomal abnormalities, ectrodactyly-ectodermal dysplasia-cleft (EEC) syndrome, the F form of acropectorovertebral dysgenesis or the F syndrome, fetal alcohol syndrome, Holt-Oram syndrome, Leopard syndrome, multiple synostosis syndrome, oligosyndactyly syndrome, Pfeiffer-like syndrome, scleroderma, split hand and foot malformatio...

  7. Fusion rules of equivariantizations of fusion categories

    OpenAIRE

    2012-01-01

    We determine the fusion rules of the equivariantization of a fusion category $\\mathcal{C}$ under the action of a finite group $G$ in terms of the fusion rules of $\\mathcal{C}$ and group-theoretical data associated to the group action. As an application we obtain a formula for the fusion rules in an equivariantization of a pointed fusion category in terms of group-theoretical data. This entails a description of the fusion rules in any braided group-theoretical fusion category.

  8. Fusion rules of equivariantizations of fusion categories

    OpenAIRE

    Burciu, Sebastian; Natale, Sonia

    2012-01-01

    We determine the fusion rules of the equivariantization of a fusion category $\\mathcal{C}$ under the action of a finite group $G$ in terms of the fusion rules of $\\mathcal{C}$ and group-theoretical data associated to the group action. As an application we obtain a formula for the fusion rules in an equivariantization of a pointed fusion category in terms of group-theoretical data. This entails a description of the fusion rules in any braided group-theoretical fusion category.

  9. Fusion research: the past is prologue

    Energy Technology Data Exchange (ETDEWEB)

    Post, R F

    1998-10-14

    At this juncture fusion research can be viewed as being at a turning point, a time to review its past and to imagine its future. Today, almost 50 years since the first serious attempts to address the daunting problem of achieving controlled fusion, we have both an opportunity and a challenge. Some predictions place fusion research today at a point midway between its first inception and its eventual maturation - in the middle of the 21st century - when fusion would become a major source of energy. Our opportunity therefore is to assess what we have learned from 50 years of hard work and use that knowledge as a starting point for new and better approaches to solving the fusion problem. Our challenge is to prove the "50 more years" prophesy wrong, by finding ways to shorten the time when fusion power becomes a reality. The thesis will be advanced that in the magnetic confinement approach to fusion open-ended magnetic confinement geometries offer much in responding to the challenge. A major advantage of open systems is that, owing to their theoretically and experimentally demonstrated ability to suppress plasma instabilities of both the MHD and the high-frequency wave-particle variety, the confinement becomes predictable from "classical," i.e., Fokker-Planck-type analysis. In a time of straitened budgetary circumstances for magnetic fusion research now being faced in the United States, the theoretical tractability of mirror-based systems is a substantial asset. In pursuing this avenue it is also necessary to keep an open mind as to the forms that mirror-based fusion power plants might take. For example, one can look to the high-energy physics community for a possible model: This community has shown the feasibility of constructing large and complex particle accelerators using superconducting magnets, vacuum chambers and complicated particle-handling technology, housed in underground tunnels that are 20 or more kilometers long. In the paper examples of mirror

  10. Fusion materials semiannual progress report for the period ending March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This is the eighteenth in a series of semiannual technical progress reports on fusion materials. This report combines research and development activities which were previously reported separately in the following progress reports: {sm_bullet} Alloy Development for Irradiation Performance. {sm_bullet} Damage Analysis and Fundamental Studies. {sm_bullet} Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide. This report has been compiled and edited under the guidance of A.F. Rowcliffe by Gabrielle Burn, Oak Ridge National Laboratory. Their efforts, and the efforts of the many persons who made technical contributions, are gratefully acknowledged.

  11. Proposal for magnetic/electromagnetic fields protection norms on national level

    OpenAIRE

    Đorđević Drago; Raković Dejan

    2008-01-01

    Introduction The modern life is not possible without application of magnetic/electromagnetic fields, which can be both helpful and harmful for human body. Influence of magnetic/electromagnetic fields on biological systems The non-ionizing radiation, especially magnetic/electromagnetic fields of all frequencies (0-300 GHz), can have many harmful effects on the human health that is confirmed by numerous epidemiological studies, studies with volunteers, animal studies, and in vitro studies. Prop...

  12. The first fusion reactor: ITER

    Science.gov (United States)

    Campbell, D. J.

    2016-11-01

    Established by the signature of the ITER Agreement in November 2006 and currently under construction at St Paul-lez-Durance in southern France, the ITER project [1,2] involves the European Union (including Switzerland), China, India, Japan, the Russian Federation, South Korea and the United States. ITER (`the way' in Latin) is a critical step in the development of fusion energy. Its role is to provide an integrated demonstration of the physics and technology required for a fusion power plant based on magnetic confinement.

  13. MAGNET

    CERN Multimedia

    by B. Curé

    2011-01-01

    The magnet operation was very satisfactory till the technical stop at the end of the year 2010. The field was ramped down on 5th December 2010, following the successful regeneration test of the turbine filters at full field on 3rd December 2010. This will limit in the future the quantity of magnet cycles, as it is no longer necessary to ramp down the magnet for this type of intervention. This is made possible by the use of the spare liquid Helium volume to cool the magnet while turbines 1 and 2 are stopped, leaving only the third turbine in operation. This obviously requires full availability of the operators to supervise the operation, as it is not automated. The cryogenics was stopped on 6th December 2010 and the magnet was left without cooling until 18th January 2011, when the cryoplant operation resumed. The magnet temperature reached 93 K. The maintenance of the vacuum pumping was done immediately after the magnet stop, when the magnet was still at very low temperature. Only the vacuum pumping of the ma...

  14. Establishment of an Institute for Fusion Studies. Technical progress report, November 1, 1994--October 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The Institute for Fusion Studies is a national center for theoretical fusion plasma physics research. Its purposes are to (1) conduct research on theoretical questions concerning the achievement of controlled fusion energy by means of magnetic confinement--including both fundamental problems of long-range significance, as well as shorter-term issues; (2) serve as a national and international center for information exchange by hosting exchange visits, conferences, and workshops; and (3) train students and postdoctoral research personnel for the fusion energy program and plasma physics research areas. During FY 1995, a number of significant scientific advances were achieved at the IFS, both in long-range fundamental problems as well as in near-term strategic issues, consistent with the Institute`s mandate. Examples of these achievements include, for example, tokamak edge physics, analytical and computational studies of ion-temperature-gradient-driven turbulent transport, alpha-particle-excited toroidal Alfven eigenmode nonlinear behavior, sophisticated simulations for the Numerical Tokamak Project, and a variety of non-tokamak and non-fusion basic plasma physics applications. Many of these projects were done in collaboration with scientists from other institutions. Research discoveries are briefly described in this report.

  15. Second Symposium on ``Current trends in international fusion research: review and assessment`` Chairman`s summary of session

    Energy Technology Data Exchange (ETDEWEB)

    Post, R.F.

    1998-02-26

    This session began with a keynote speech by B. Coppi of M.I.T., entitled: ``Physics of Fusion Burning Plasmas, Ignition, and Relevant Technology Issues.`` It continued with a second paper on the tokamak approach to fusion, presented by E. Mazzucato of the Princeton Plasma Physics Laboratory, entitled ``High Confinement Plasma Confinement Regime in TFTR Configurations with Reversed Magnetic Shear.`` The session continued with three talks discussing various aspects of the so-called ``Field Reversed Configuration`` (FRC), and concluded with a talk on a more general topic. The first of the three FRC papers, presented by J. Slough of the University of Washington, was entitled ``FRC Reactor for Deep Space Propulsion.`` This paper was followed by a paper by S. Goto of the Plasma Physics Laboratory of Osaka University in Japan, entitled ``Experimental Initiation of Field-Reversed Configuration (FRC) Toward Helium-3 Fusion.`` The third of the FRC papers, authored by H. Mimoto and Y. Tomito of the National Institute for Fusion Science, Nagoya, Japan, and presented by Y. Tomita was entitled ``Helium-3 Fusion Based on a Field-Reversed Configuration.`` The session was concluded with a paper presented by D. Ryutov of the Lawrence Livermore National Laboratory entitled: ``A User Facility for Research on Fusion Systems with Dense Plasmas.``

  16. Progress in the Development of Superconducting Quadrupoles forHeavy-ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, R.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-08-19

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  17. Progress in the development of superconducting quadrupoles for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-05-24

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  18. Recent developments concerning the fusion; Developpements recents sur la fusion

    Energy Technology Data Exchange (ETDEWEB)

    Jacquinot, J. [CEA/Cadarache, Dept. de Recherches sur la Fusion Controlee, DRFC, 13 - Saint Paul lez Durance (France); Andre, M. [CEA/DAM Ile de France, 91 - Bruyeres Le Chatel (France); Aymar, R. [ITER Joint Central Team Garching, Muenchen (Germany)] [and others

    2000-09-04

    Organized the 9 march 2000 by the SFEN, this meeting on the european program concerning the fusion, showed the utility of the exploitation and the enhancement of the actual technology (JET, Tore Supra, ASDEX) and the importance of the Europe engagement in the ITER program. The physical stakes for the magnetic fusion have been developed with a presentation of the progresses in the knowledge of the stability limits. A paper on the inertial fusion was based on the LMJ (Laser MegaJoule) project. The two blanket concepts chosen in the scope of the european program on the tritium blankets, have been discussed. These concepts will be validated by irradiation tests in the ITER-FEAT and adapted for a future reactor. (A.L.B.)

  19. FUSION WORLD

    Institute of Scientific and Technical Information of China (English)

    Caroline; 黄颖(翻译)

    2009-01-01

    Fusion World”科技展示体验中心是英国设计公司MET Studio为新加坡科技研究局(A*Star)的科学工程委员会(SERC)所设计的,位于启汇城的办公地点,用于展示该委员会的精选技术作品,以吸引潜在的客户和启汇城内的学生购买群体。

  20. Vlasov-Fokker-Planck modeling of magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Alexander [Univ. of Michigan, Ann Arbor, MI (United States)

    2016-08-01

    Understanding the magnetic fields that can develop in high-power-laser interactions with solid-density plasma is important because such fields significantly modify both the magnitude and direction of electron heat fluxes. The dynamics of such fields evidently have consequences for inertial fusion energy applications, as the coupling of the laser beams with the walls or pellet and the development of temperature inhomogeneities are critical to the uniformity of the implosion and potentially the success of, for example, the National Ignition Facility. To study these effects, we used the code Impacta, a two-dimensional, fully implicit, Vlasov-Fokker-Planck code with self-consistent magnetic fields and a hydrodynamic ion model, designed for nanosecond time-scale laser-plasma interactions. Heat-flux effects in Ohm’s law under non-local conditions was investigated; physics that is not well captured by standard numerical models but is nevertheless important in fusion-related scenarios. Under such conditions there are numerous interesting physical effects, such as collisional magnetic instabilities, amplification of magnetic fields, re-emergence of non-locality through magnetic convection, and reconnection of magnetic field lines and redistribution of thermal energy. In this project highlights included the first full scale kinetic simulations of a magnetized hohlraum [Joglekar 2016] and the discovery of a new magnetic reconnection mechanism [Joglekar 2014] as well as a completed PhD thesis and the production of a new code for Inertial Fusion research.

  1. Fusion research at Culham site; Fuusiotutkimus Culhamissa

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, P.; Toppila, T

    1998-12-31

    One of the many targets on the Finnish Nuclear Society (ATS) excursion to England was the Culham fusion research site. The site has divided into two parts. One of them is UKAEA Fusion with small scale fusion reactors and 200 employees. UKAEA has 3 fusion reactors at Culham site. One of is the START (Small Tight Aspect Ratio Tokamak) which was operational since 1991 but is today already out of operation. UKAEA has been operating a JET-like tokamak fusion reactor COMPASS-D since 1989. The latest of three reactors is MAST (Mega Amp Spherical Tokamak), which is still under construction. The first plasma will take place in the end of 1998. Another part of Culham site is JET (Joint European Torus), an all-European fusion undertaking with 350 employees. 150 of them are from various European countries and the rest 200 are employed by UKAEA. JET is the biggest fusion reactor ever and it represents the latest step in world wide fusion programme. In October 1997 JET achieved a world record in fusion power and energy. JET produced 16,1 MW power for 1 s and totally 21,7 MJ energy. This is the closest attempt to achieve break-even conditions. The next step in world wide fusion programme will be international ITER-reactor. This undertaking has some financial problems, since United States has taken distance to magnetic fusion research and moved closer to inertial fusion with funding of US Department of Defence. The planned reactor, however, is physically twice as big as JET. The step after this phase will be DEMO, which is purposed to produce fusion energy. According to our hosts in Culham this phase is 40 years ahead. (author)

  2. Carpal Fusion

    Directory of Open Access Journals (Sweden)

    Jalal Jalalshokouhi*

    2012-05-01

    Full Text Available Carpal fusion may be seen in hereditary and nonhereditary conditions such as acrocallosal syndrome,acromegaly, Apert syndrome, arthrogryposis, Carpenter syndrome, chromosomal abnormalities, ectrodactyly-ectodermal dysplasia-cleft (EEC syndrome, the F form of acropectorovertebral dysgenesis or the F syndrome, fetal alcohol syndrome, Holt-Oram syndrome, Leopard syndrome, multiple synostosis syndrome, oligosyndactyly syndrome, Pfeiffer-like syndrome, scleroderma, split hand and foot malformation, Stickler syndrome, thalidomide embryopathy, Turner syndrome and many other conditions as mentioned in Rubinstein-Taybi's book. Sometimes there is no known causative disease.Diagnosis is usually made by plain X-ray during studying a syndrome or congenital disease or could be an incidental finding like our patients. Hand bone anomalies are more common in syndromes or other congenital or non-hereditary conditions, but polydactyly, syndactyly or oligodactyly and carpal fusions are interesting. X-ray is the modality of choice, but MRI and X-ray CT with multiplanar reconstructions may be used for diagnosis.

  3. Plasma physics for controlled fusion

    CERN Document Server

    Miyamoto, Kenro

    2016-01-01

    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator includi...

  4. Fusion Enhanced Vehicle Level Diagnostic System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Technology Connection, Inc. in conjunction with its partner, Vanderbilt University, is proposing to build a Fusion-enhanced Vehicle Diagnostics System (FVDS)...

  5. Desensitized Optimal Filtering and Sensor Fusion Tool Kit Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Research on desensitized optimal filtering techniques and a navigation and sensor fusion tool kit using advanced filtering techniques is proposed. Research focuses...

  6. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet was energised at the beginning of March 2012 at a low current to check all the MSS safety chains. Then the magnet was ramped up to 3.8 T on 6 March 2012. Unfortunately two days later an unintentional switch OFF of the power converter caused a slow dump. This was due to a misunderstanding of the CCC (CERN Control Centre) concerning the procedure to apply for the CMS converter control according to the beam-mode status at that time. Following this event, the third one since 2009, a discussion was initiated to define possible improvement, not only on software and procedures in the CCC, but also to evaluate the possibility to upgrade the CMS hardware to prevent such discharge from occurring because of incorrect procedure implementations. The magnet operation itself was smooth, and no power cuts took place. As a result, the number of magnetic cycles was reduced to the minimum, with only two full magnetic cycles from 0 T to 3.8 T. Nevertheless the magnet suffered four stops of the cryogeni...

  7. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    Operation of the magnet has gone quite smoothly during the first half of this year. The magnet has been at 4.5K for the full period since January. There was an unplanned short stop due to the CERN-wide power outage on May 28th, which caused a slow dump of the magnet. Since this occurred just before a planned technical stop of the LHC, during which access in the experimental cavern was authorized, it was decided to leave the magnet OFF until 2nd June, when magnet was ramped up again to 3.8T. The magnet system experienced a fault also resulting in a slow dump on April 14th. This was triggered by a thermostat on a filter choke in the 20kA DC power converter. The threshold of this thermostat is 65°C. However, no variation in the water-cooling flow rate or temperature was observed. Vibration may have been the root cause of the fault. All the thermostats have been checked, together with the cables, connectors and the read out card. The tightening of the inductance fixations has also been checked. More tem...

  8. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      Following the unexpected magnet stops last August due to sequences of unfortunate events on the services and cryogenics [see CMS internal report], a few more events and initiatives again disrupted the magnet operation. All the magnet parameters stayed at their nominal values during this period without any fault or alarm on the magnet control and safety systems. The magnet was stopped for the September technical stop to allow interventions in the experimental cavern on the detector services. On 1 October, to prepare the transfer of the liquid nitrogen tank on its new location, several control cables had to be removed. One cable was cut mistakenly, causing a digital input card to switch off, resulting in a cold-box (CB) stop. This tank is used for the pre-cooling of the magnet from room temperature down to 80 K, and for this reason it is controlled through the cryogenics control system. Since the connection of the CB was only allowed for a field below 2 T to avoid the risk of triggering a fast d...

  9. Inertial-confinement fusion with lasers

    Science.gov (United States)

    Betti, R.; Hurricane, O. A.

    2016-05-01

    The quest for controlled fusion energy has been ongoing for over a half century. The demonstration of ignition and energy gain from thermonuclear fuels in the laboratory has been a major goal of fusion research for decades. Thermonuclear ignition is widely considered a milestone in the development of fusion energy, as well as a major scientific achievement with important applications in national security and basic sciences. The US is arguably the world leader in the inertial confinement approach to fusion and has invested in large facilities to pursue it, with the objective of establishing the science related to the safety and reliability of the stockpile of nuclear weapons. Although significant progress has been made in recent years, major challenges still remain in the quest for thermonuclear ignition via laser fusion. Here, we review the current state of the art in inertial confinement fusion research and describe the underlying physical principles.

  10. Nuclear Fusion Fuel Cycle Research Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hongsuk; Koo, Daeseo; Park, Jongcheol; Kim, Yeanjin [KAERI, Daejeon (Korea, Republic of); Yun, Sei-Hun [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    As a part of the International Thermonuclear Experimental Reactor (ITER) Project, we at the Korea Atomic Energy Research Institute (KAERI) and our National Fusion Research Institute (NFRI) colleagues are investigating nuclear fusion fuel cycle hardware including a nuclear fusion fuel Storage and Delivery System (SDS). To have a better knowledge of the nuclear fusion fuel cycle, we present our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). To have better knowledge of the nuclear fusion fuel cycle, we presented our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). Our efforts to enhance the tritium confinement will be continued for the development of cleaner nuclear fusion power plants.

  11. Fusion Reactor Materials semiannual progress report for the period ending March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    This is the twelfth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  12. Fusion reactor materials semiannual progress report for the period ending March 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1991-07-01

    This is the tenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: alloy development for irradiation performance; damage analysis and fundamental studies; special purpose materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of program participants, and to provide a means of communicating the efforts of materials scientists to the test of the fusion community, both nationally and worldwide.

  13. Fusion reactor materials: Semiannual progress report for period ending September 30, 1987

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1988-03-01

    This is the third in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following technical progress reports: Alloy Development for Irradiation Performances; Damage Analysis and Fundamental Studies; Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  14. Fusion reactor materials semiannual progress report for the period ending September 30, 1989

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-01-01

    This is the seventh in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following technical progress reports: alloy development for irradiation performance, damage analysis and fundamental studies, and special purpose materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  15. Fusion reactor materials semiannual progress report for period ending September 30, 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    This is the ninth in series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following technical progress reports: Alloy Development of Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  16. A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

    Science.gov (United States)

    Sutcliffe, G. D.; Milanese, L. M.; Orozco, D.; Lahmann, B.; Gatu Johnson, M.; Séguin, F. H.; Sio, H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.; Park, H.-S.; Rygg, J. R.; Casey, D. T.; Bionta, R.; Turnbull, D. P.; Huntington, C. M.; Ross, J. S.; Zylstra, A. B.; Rosenberg, M. J.; Glebov, V. Yu.

    2016-11-01

    CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint of the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.

  17. A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sutcliffe, G. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Milanese, L. M. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Orozco, D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Lahmann, B. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Gatu Johnson, M. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Séguin, F. H. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Sio, H. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Frenje, J. A. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Li, C. K. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; Park, H. -S. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Rygg, J. R. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Casey, D. T. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Bionta, R. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Turnbull, D. P. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Huntington, C. M. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Ross, J. S. [Lawrence Livermore National Laboratory, Livermore, California 94550, USA; Zylstra, A. B. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA; Rosenberg, M. J. [Laboratory for Laser Energetics, Rochester, New York 14623, USA; Glebov, V. Yu. [Laboratory for Laser Energetics, Rochester, New York 14623, USA

    2016-08-05

    CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint of the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.

  18. A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sutcliffe, G. D., E-mail: gdsut@mit.edu; Milanese, L. M.; Orozco, D.; Lahmann, B.; Gatu Johnson, M.; Séguin, F. H.; Sio, H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Park, H.-S.; Rygg, J. R.; Casey, D. T.; Bionta, R.; Turnbull, D. P.; Huntington, C. M.; Ross, J. S. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Zylstra, A. B. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Rosenberg, M. J.; Glebov, V. Yu. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States)

    2016-11-15

    CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint of the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.

  19. Laboratory for Laser Energetics annual report, 1 October 1991--30 September 1992. Inertial Fusion Program and National Laser Users Facility Program

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    This is an annual report covering research progress on laser fusion and the OMEGA Upgrade design and development. In laser fusion, line-spectroscopy methods were demonstrated to be useful in diagnosing the core temperature and densities of polymer-shell targets; a theoretical analysis of nonlocal heat transport effects on filamentation of light in plasmas confirms that the principle mechanism driving filamentation is kinetic thermal rather than ponderomotive; a new method (spatial beam deflection) to produce laser pulses of arbitrary shape was developed; laser-plasma x-ray emission was measured using photodiode arrays; experiments on long-scale-length plasmas have shown that smoothing by spectral dispersion has proven effective in reducing Raman scattering; a method for increasing the gas-retention time of polymer shell targets was developed by overcoating them with aluminum. Experiments relating to the OMEGA Upgrade are described.

  20. BOOK REVIEW: Fusion: The Energy of the Universe

    Science.gov (United States)

    Lister, J.

    2006-05-01

    trails', since it is so tempting to produce a `backroom' solution to mankind's hunger for energy. Unfortunately, Chapter 8 can only regret that none of them has passed closer peer review. Chapters 9 and 10 concentrate on the `tokamak' concept for magnetic confinement, the basis for the JET and ITER projects, as well as for a wealth of smaller, national projects. The hopes and the disappointments are well and very frankly illustrated. The motivation for building a project of the size of ITER is made very clear. Present fusion research cannot forget that its mission is to develop an industrial reactor, not just a powerful research tool. Chapter 11 presents the major challenges between ITER and a reactor. Finally, Chapter 12 reminds us of why we need energy, why we do not have a credible solution at the mid-term (20 years) and why we have no solution in the longer term. The public awareness of this is growing, at last, even though the arguments were all on the table in the 1970's. This chapter therefore closes the book by bringing the reader back to earth rather suitably with the hard reality of energy needs and the absence of credible policies. This book has already received impressive approval among a wide range of people, since it so evidently succeeds in its goal to explain Fusion to many levels of reader. Gary McCracken and Peter Stott (one time editor of Plasma Physics and Controlled Fusion) both dedicated their careers to magnetic confinement fusion, mostly at Culham working on UKAEA projects and later on the JET project. They were both deeply involved with international collaborations and both were working abroad when they retired. The mixture between ideas, developments and people is most successfully developed. They clearly underline the importance of strong international collaboration on which this field depends. This open background is tangible in their recently published work, in which they have tried to communicate their love and understanding of this exciting

  1. Design and preliminary test results of the 40 MW power supply at the National High Magnetic Field Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Boenig, H.J. [Los Alamos National Lab., NM (United States); Bogdan, F.; Morris, G.C. [ABB Drives Inc., New Berlin, WI (United States); Ferner, J.A.; Schneider-Muntau, H.J. [National High Magnetic Field Lab., Tallahassee, FL (United States); Rumrill, R.H.; Rumrill, R.S. [Alpha Scientific Electronics Inc., Hayward, CA (United States)

    1993-11-01

    Four highly stabilized, steady-state, 10 MW power supplies have been installed at the National High Magnetic Field Laboratory in Tallahassee, FL. Each supply consists of a 12.5 kV vacuum circuit breaker, two three-winding, step-down transformers, a 24-pulse rectifier with interphase reactors and freewheeling diodes, and a passive and an active filter. Two different transformer tap settings allow dc supply output voltages of 400 and 500 V. The rated current of a supply is 17 kA and each supply has a one hour overload capability of 20 kA. The power supply output bus system, including a reversing switch at the input and 2 {times} 16 disconnect switches at the output, connects each supply to 16 different magnet cells. The design of the power supply is described and preliminary test results with a supply feeding a 10 MW resistive load are presented.

  2. ZHANG Caihong. Fusion algorithm of H¥ and sliding-mode control for magnetic levitation systems%H¥与滑模融合控制算法在磁悬浮系统中的应用

    Institute of Scientific and Technical Information of China (English)

    李丹丹; 何荣卜; 张彩红

    2014-01-01

    磁悬浮系统在实际运行中会出现模型摄动和各种外界干扰,提高磁悬浮系统的鲁棒性非常重要,给出了磁悬浮系统的数学模型;结合H∞控制和滑模控制的优点,给出一种 H¥控制和滑模控制的融合算法,把该算法应用在磁悬浮系统中;通过Matlab仿真,验证了该算法能有效抑制磁悬浮系统中存在的确定性和不确定性干扰,从而使控制系统的性能得到提高。%Magnetic levitation control system has model perturbation and a variety of outside interference during operation, so, improving the robustness of magnetic levitation system is very important. This paper gives a mathematical model of magnetic levitation system;a fusion algorithm of H¥ and sliding-mode control is discussed;simulation is obtained by Matlab tool. The results show that the algorithm is robust to the uncertainty of the system on the matching and non-matching at the same time.

  3. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet and its sub-systems were stopped at the beginning of the winter shutdown on 8th December 2011. The magnet was left without cooling during the cryogenics maintenance until 17th January 2012, when the cryoplant operation resumed. The magnet temperature reached 93 K. The vacuum pumping was maintained during this period. During this shutdown, the yearly maintenance was performed on the cryogenics, the vacuum pumps, the magnet control and safety systems, and the power converter and discharge lines. Several preventive actions led to the replacement of the electrovalve command coils, and the 20A DC power supplies of the magnet control system. The filters were cleaned on the demineralised water circuits. The oil of the diffusion pumps was changed. On the cryogenics, warm nitrogen at 343 K was circulated in the cold box to regenerate the filters and the heat exchangers. The coalescing filters have been replaced at the inlet of both the turbines and the lubricant trapping unit. The active cha...

  4. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet was successfully operated at the end of the year 2009 despite some technical problems on the cryogenics. The magnet was ramped up to 3.8 T at the end of November until December 16th when the shutdown started. The magnet operation met a few unexpected stops. The field was reduced to 3.5 T for about 5 hours on December 3rd due to a faulty pressure sensor on the helium compressor. The following day the CERN CCC stopped unintentionally the power converters of the LHC and the experiments, triggering a ramp down that was stopped at 2.7 T. The magnet was back at 3.8 T about 6 hours after CCC sent the CERN-wide command. Three days later, a slow dump was triggered due to a stop of the pump feeding the power converter water-cooling circuit, during an intervention on the water-cooling plant done after several disturbances on the electrical distribution network. The magnet was back at 3.8 T in the evening the same day. On December 10th a break occurred in one turbine of the cold box producing the liquid ...

  5. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

      The magnet was operated without any problem until the end of the LHC run in February 2013, apart from a CERN-wide power glitch on 10 January 2013 that affected the CMS refrigerator, causing a ramp down to 2 T in order to reconnect the coldbox. Another CERN-wide power glitch on 15 January 2013 didn’t affect the magnet subsystems, the cryoplant or the power converter. At the end of the magnet run, the reconnection of the coldbox at 2.5 T was tested. The process will be updated, in particular the parameters of some PID valve controllers. The helium flow of the current leads was reduced but only for a few seconds. The exercise will be repeated with the revised parameters to validate the automatic reconnection process of the coldbox. During LS1, the water-cooling services will be reduced and many interventions are planned on the electrical services. Therefore, the magnet cryogenics and subsystems will be stopped for several months, and the magnet cannot be kept cold. In order to avoid unc...

  6. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The CMS magnet has been running steadily and smoothly since the summer, with no detected flaw. The magnet instrumentation is entirely operational and all the parameters are at their nominal values. Three power cuts on the electrical network affected the magnet run in the past five months, with no impact on the data-taking as the accelerator was also affected at the same time. On 22nd June, a thunderstorm caused a power glitch on the service electrical network. The primary water cooling at Point 5 was stopped. Despite a quick restart of the water cooling, the inlet temperature of the demineralised water on the busbar cooling circuit increased by 5 °C, up to 23.3 °C. It was kept below the threshold of 27 °C by switching off other cooling circuits to avoid the trigger of a slow dump of the magnet. The cold box of the cryogenics also stopped. Part of the spare liquid helium volume was used to maintain the cooling of the magnet at 4.5 K. The operators of the cryogenics quickly restarted ...

  7. Fusion Plasma Theory project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program.

  8. Fusion Power Program. Quarterly progress report, October--December 1978

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    This quarterly report summarizes the Argonne National Laboratory work performed for the Office of Fusion Energy during the October--December 1978 quarter in the following research and development areas: materials; energy storage and transfer; tritium containment, recovery and control; advanced reactor design; atomic data; reactor safety; fusion-fission hybrid systems; alternate applications of fusion energy; and other work related to fusion power. Three separate abstracts were prepared for the included sections. (MOW)

  9. Fusion Power Program biannual progress report, April-September 1979

    Energy Technology Data Exchange (ETDEWEB)

    1980-02-01

    This biannual report summarizes the Argonne National Laboratory work performed for the Office of Fusion Energy during the April-September 1979 quarter in the following research and development areas: materials; energy storage and transfer; tritium containment, recovery and control; advanced reactor design; atomic data; reactor safety; fusion-fission hybrid systems; alternate applications of fusion energy; and other work related to fusion power. Separate abstracts were prepared for three sections. (MOW)

  10. MAGNETS

    Science.gov (United States)

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  11. Design of a Large Bore 60-T Pulse Magnet for Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    LESCH,B.; LI,L.; PERNAMBUCO-WISE,P.; ROVANG,DEAN C.; SCHNEIDER-MUNTAU,H.J.

    1999-09-23

    The design of a new pulsed magnet system for the generation of intense electron beams is presented. Determined by the required magnetic field profile along the axis, the magnet system consists of two coils (Coil No.1 and No.2) separated by a 32-mm axial gap. Each coil is energized independently. Both coils are internally reinforced with HIM Zylon fiber/epoxy composite. Coil No.1 made with AI-15 Glidcop wire has a bore of 110-mm diameter and is 200-mm long; it is energized by a 1.3-MJ, 13-kV capacitor bank. The magnetic field at the center of this coil is 30 T. Coil No.2 made with CuNb wire has a bore of 45 mm diameter, generates 60 T with a pulse duration of 60 ms, and is powered by a 4.0-MJ, 17.7-kV capacitor bank. We present design criteria, the coupling of the magnets, and the normal and the fault conditions during operation.

  12. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The magnet ran smoothly in the last few months until a fast dump occurred on 9th May 2011. Fortunately, this occurred in the afternoon of the first day of the technical stop. The fast dump was due to a valve position controller that caused the sudden closure of a valve. This valve is used to regulate the helium flow on one of the two current leads, which electrically connects the coil at 4.5 K to the busbars at room temperature. With no helium flow on the lead, the voltage drop and the temperatures across the leads increase up to the defined thresholds, triggering a fast dump through the Magnet Safety System (MSS). The automatic reaction triggered by the MSS worked properly. The helium release was limited as the pressure rise was just at the limit of the safety valve opening pressure. The average temperature of the magnet reached 72 K. It took four days to recover the temperature and refill the helium volumes. The faulty valve controller was replaced by a spare one before the magnet ramp-up resumed....

  13. Fusion Utility in the Knudsen Layer

    Energy Technology Data Exchange (ETDEWEB)

    Davidovits, Seth [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Fisch, Nathaniel J. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2014-08-01

    In inertial confi nement fusion, the loss of fast ions from the edge of the fusing hot-spot region reduces the reactivity below its Maxwellian value. The loss of fast ions may be pronounced because of the long mean free paths of fast ions, compared to those of thermal ions. We introduce a fusion utility function to demonstrate essential features of this Knudsen layer e ffect, in both magnetized and unmagnetized cases. The fusion utility concept is also used to evaluate restoring the reactivity in the Knudsen layer by manipulating fast ions in phase space using waves.

  14. Nuclear fusion research in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Cheetham, A.D. [Australian National Univ., Canberra, ACT (Australia). Plasma Research Lab

    1997-12-31

    In this paper the recently formed National Plasma Fusion Research Facility centred around the H-1NF Heliac, located at the Australian National University, the Institute of Advanced Studies is described in the context of the international Stellarator program and the national collaboration with the Australian Fusion Research Group. The objectives of the facility and the planned physics research program over the next five years are discussed and some recent results will be presented. The facility will support investigations in the following research areas: finite pressure equilibrium and stability, transport in high temperature plasmas, plasma heating and formation, instabilities and turbulence, edge plasma physics and advanced diagnostic development. 4 refs., 2 tabs., 5 figs.

  15. MHD Simulations for Fusion Applications

    Energy Technology Data Exchange (ETDEWEB)

    Jardin, S.C. [Princeton Plasma Physics Laboratory, P.O. box 451, Princeton, NJ 08543 (United States)

    2011-07-01

    Nuclear fusion holds forth the promise of being a clean and safe solution to meet the world's energy demand in the foreseeable future without producing long-lived radioactive waste or weapons-grade material. The most mature configuration for magnetically confining a fusion plasma is the tokamak; a current carrying toroidal plasma characterized by strong externally produced magnetic fields. The temperatures, densities, and current will diffuse across the magnetic field lines at some rate, determining the confinement properties of the tokamak. The tokamak can also develop global instabilities if the current and/or pressure exceed certain instability thresholds. This set of lectures is aimed at describing analytical formulations and associated numerical methods for quantitatively describing both the slow (diffusive) motion associated with transport and the faster (wave-like) motion associated with instabilities. The former uses slow time scale ordering to remove the wave-like motion, and a time dependent field-aligned coordinate transformation to isolate the cross-field transport from the faster transport along the magnetic field lines. The latter uses a combination of high-order finite elements, a particular representation of the magnetic and velocity vector fields, and an implicit time advance algorithm with desirable properties. This paper is followed by the slides of the lectures. (author)

  16. Occupational exposure to magnetic fields and electric shocks and risk of ALS : the Swiss National Cohort

    NARCIS (Netherlands)

    Huss, Anke|info:eu-repo/dai/nl/331385880; Spoerri, Adrian; Egger, Matthias; Kromhout, Hans|info:eu-repo/dai/nl/074385224; Vermeulen, Roel|info:eu-repo/dai/nl/216532620

    2015-01-01

    Amyotrophic lateral sclerosis (ALS) has been associated with exposures in so-called 'electrical occupations'. It is unclear if this possible link may be explained by exposure to extremely low-frequency magnetic fields (ELF-MF) or by electrical shocks. We evaluated ALS mortality in 2000-2008 and expo

  17. Preempting the Storm: Mitigating America’s National Security Vulnerability to Disruptive Magnetic Events

    Science.gov (United States)

    2011-02-16

    change of the magnetic flux through the circuit. Sadiku , M. N. O. (2007). Elements of Electromagnetics (fourth ed.). New York (USA)/Oxford (UK...Peter Ogden. "The Security Implications of Climate Change." The Washington Quarterly. Sadiku , M. N. O. Elements of Electromagnetics. New York

  18. Be Bold : An Alternative Plan for Fusion Research

    Energy Technology Data Exchange (ETDEWEB)

    Wurden, Glen Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-15

    Government sponsored magnetic fusion energy research in the USA has been on downward trajectory since the early 1990’s. The present path is unsustainable. Indeed, our research community and national research facilities are withering from old-age and lack of investment. The present product (tokamak-centric production of electricity) does not yet work, will not be economic, and is clearly not valued or needed by our society. Even if a prototype existed at any cost, DT-based fusion energy would come too late to significantly impact the reduction of CO2 emissions in this century. This white paper outlines what “being bold” could mean with respect to the invention and application of nuclear fusion technologies, and how the USA could once again set a visionary example for the world. I present the discussion in two parts, reflecting on the NAS panel two-part assignment of a plan “with” and “without” ITER.

  19. A direct fusion drive for rocket propulsion

    Science.gov (United States)

    Razin, Yosef S.; Pajer, Gary; Breton, Mary; Ham, Eric; Mueller, Joseph; Paluszek, Michael; Glasser, Alan H.; Cohen, Samuel A.

    2014-12-01

    The Direct Fusion Drive (DFD), a compact, anuetronic fusion engine, will enable more challenging exploration missions in the solar system. The engine proposed here uses a deuterium-helium-3 reaction to produce fusion energy by employing a novel field-reversed configuration (FRC) for magnetic confinement. The FRC has a simple linear solenoid coil geometry yet generates higher plasma pressure, hence higher fusion power density, for a given magnetic field strength than other magnetic-confinement plasma devices. Waste heat generated from the plasma's Bremsstrahlung and synchrotron radiation is recycled to maintain the fusion temperature. The charged reaction products, augmented by additional propellant, are exhausted through a magnetic nozzle. A 1 MW DFD is presented in the context of a mission to deploy the James Webb Space Telescope (6200 kg) from GPS orbit to a Sun-Earth L2 halo orbit in 37 days using just 353 kg of propellant and about half a kilogram of 3He. The engine is designed to produce 40 N of thrust with an exhaust velocity of 56.5 km/s and has a specific power of 0.18 kW/kg.

  20. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

    The magnet is fully stopped and at room temperature. The maintenance works and consolidation activities on the magnet sub-systems are progressing. To consolidate the cryogenic installation, two redundant helium compressors will be installed as ‘hot spares’, to avoid the risk of a magnet downtime in case of a major failure of a compressor unit during operation. The screw compressors, their motors, the mechanical couplings and the concrete blocks are already available and stored at P5. The metallic structure used to access the existing compressors in SH5 will be modified to allow the installation of the two redundant ones. The plan is to finish the installation and commissioning of the hot spare compressors before the summer 2014. In the meantime, a bypass on the high-pressure helium piping will be installed for the connection of a helium drier unit later during the Long Shutdown 1, keeping this installation out of the schedule critical path. A proposal is now being prepared for the con...