National Library of Energy BETA

Sample records for density plasma science

  1. COLLOQUIUM: Frontiers in Plasma Science: A High Energy Density Perspective

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | Princeton Plasma Physics Lab January 13, 2016, 4:15pm to 5:30pm Colloquia MBG AUDITORIUM COLLOQUIUM: Frontiers in Plasma Science: A High Energy Density Perspective Dr. Bruce A. Remington Lawrence Livermore National Laboratory The potential for ground-breaking research in plasma physics in high energy density (HED) regimes is compelling. The combination of HED facilities around the world spanning microjoules to megajoules, with time scales ranging from femtoseconds to microseconds enables

  2. High-Energy-Density Plasmas, Fluids

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Capabilities » High-Energy-Density Plasmas, Fluids /science-innovation/_assets/images/icon-science.jpg High-Energy-Density Plasmas, Fluids National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. TRIDENT target chamber Sasi Palaniyappan, right, and Rahul Shah left inside a target chamber where the TRIDENT short pulse laser is aimed at a very

  3. Amplifying Magnetic Fields in High Energy Density Plasmas | U...

    Office of Science (SC) Website

    Amplifying Magnetic Fields in High Energy Density Plasmas Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities ...

  4. Science on Tap - Plasmas

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science on Tap - Plasmas Science on Tap - Plasmas WHEN: Apr 21, 2016 5:30 PM - 7:00 PM WHERE: UnQuarked Wine Room 145 Central Park Square, Los Alamos, New Mexico 87544 USA CONTACT: Linda Anderman (505) 665-9196 CATEGORY: Bradbury INTERNAL: Calendar Login Science on tap Event Description Science On Tap happens every third Thursday of the month, featuring a new topic each week. It begins with an informal 15-minute talk and is followed by a lively group discussion. Observing the stuff of stars (and

  5. Basic Plasma Science | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Basic Plasma Science Key Laboratory projects include the study of Hall thrusters that satellites and space probes use for propulsion. PPPL's Hall Thruster Experiment (HTX) strives to understand the physics of Hall thrusters and related systems that expel plasma as a propellant. Hall thrusters originated in the Soviet Union in the 1960s and research and development are carried out today in the United States, the European Union, Russia, Japan, Korea and China. PPPL research has expanded knowledge

  6. Plasma density diagnostic for capillary-discharge based plasma...

    Office of Scientific and Technical Information (OSTI)

    Plasma density diagnostic for capillary-discharge based plasma channels Authors: Daniels, J. 1 Search SciTech Connect for author "Daniels, J." Search SciTech Connect for...

  7. Using Radio Waves to Control Fusion Plasma Density

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using Radio Waves to Control Fusion Plasma Density Using Radio Waves to Control Fusion Plasma Density Simulations Run at NERSC Support Fusion Experiments at MIT, General Atomics ...

  8. High Energy Density Laboratory Plasmas Program | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Jobs Apply for Our Jobs Our Jobs Working at NNSA Blog Home High Energy Density Laboratory Plasmas Program High Energy Density Laboratory Plasmas Program NNSA invests in next ...

  9. High energy density Z-pinch plasmas using flow stabilization

    SciTech Connect (OSTI)

    Shumlak, U. Golingo, R. P. Nelson, B. A. Bowers, C. A. Doty, S. A. Forbes, E. G. Hughes, M. C. Kim, B. Knecht, S. D. Lambert, K. K. Lowrie, W. Ross, M. P. Weed, J. R.

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and scaling analyses will be presented. In addition to studying fundamental plasma science and high energy density physics, the ZaP and ZaP-HD experiments can be applied to laboratory astrophysics.

  10. Interferometer for the measurement of plasma density

    DOE Patents [OSTI]

    Jacobson, Abram R. (Los Alamos, NM)

    1980-01-01

    An interferometer which combines the advantages of a coupled cavity interferometer requiring alignment of only one light beam, and a quadrature interferometer which has the ability to track multi-fringe phase excursions unambiguously. The device utilizes a Bragg cell for generating a signal which is electronically analyzed to unambiguously determine phase modulation which is proportional to the path integral of the plasma density.

  11. Extreme hydrogen plasma densities achieved in a linear plasma generator

    SciTech Connect (OSTI)

    Rooij, G. J. van; Veremiyenko, V. P.; Goedheer, W. J.; de Groot, B.; Kleyn, A. W.; Smeets, P. H. M.; Versloot, T. W.; Whyte, D. G.; Engeln, R.; Schram, D. C.; Cardozo, N. J. Lopes

    2007-03-19

    A magnetized hydrogen plasma beam was generated with a cascaded arc, expanding in a vacuum vessel at an axial magnetic field of up to 1.6 T. Its characteristics were measured at a distance of 4 cm from the nozzle: up to a 2 cm beam diameter, 7.5x10{sup 20} m{sup -3} electron density, {approx}2 eV electron and ion temperatures, and 3.5 km/s axial plasma velocity. This gives a 2.6x10{sup 24} H{sup +} m{sup -2} s{sup -1} peak ion flux density, which is unprecedented in linear plasma generators. The high efficiency of the source is obtained by the combined action of the magnetic field and an optimized nozzle geometry. This is interpreted as a cross-field return current that leads to power dissipation in the beam just outside the source.

  12. NSTX Diagnostics for Fusion Plasma Science Studies

    SciTech Connect (OSTI)

    R. Kaita; D. Johnson; L. Roquemore; M. Bitter; F. Levinton; F. Paoletti; D. Stutman; and the NSTX Team

    2001-07-05

    This paper will discuss how plasma science issues are addressed by the diagnostics for the National Spherical Torus Experiment (NSTX), the newest large-scale machine in the magnetic confinement fusion (MCF) program. The development of new schemes for plasma confinement involves the interplay of experimental results and theoretical interpretations. A fundamental requirement, for example, is a determination of the equilibria for these configurations. For MCF, this is well established in the solutions of the Grad-Shafranov equation. While it is simple to state its basis in the balance between the kinetic and magnetic pressures, what they are as functions of space and time are often not easy to obtain. Quantities like the plasma pressure and current density are not directly measurable. They are derived from data that are themselves complex products of more basic parameters. The same difficulties apply to the understanding of plasma instabilities. Not only are the needs for spatial and temporal resolution more stringent, but the wave parameters which characterize the instabilities are difficult to resolve. We will show how solutions to the problems of diagnostic design on NSTX, and the physics insight the data analysis provides, benefits both NSTX and the broader scientific community.

  13. Particle Gas Target for High Density Laser Produced Plasmas Charles...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Particle Gas Target for High Density Laser Produced Plasmas Charles H. Skinner, Nathaniel Fisch, and Ernest Valeo This invention is a novel "particle gas" cell for achieving plasma...

  14. Using Radio Waves to Control Fusion Plasma Density

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using Radio Waves to Control Fusion Plasma Density Using Radio Waves to Control Fusion Plasma Density Simulations Run at NERSC Support Fusion Experiments at MIT, General Atomics October 29, 2014 Radiowavesplasma Supercomputer simulation shows turbulent density fluctuations in the core of the Alcator C-Mod tokamak during strong electron heating. Image: Darin Ernst, MIT Recent fusion experiments on the DIII-D tokamak at General Atomics and the Alcator C-Mod tokamak at Massachusetts Institute of

  15. Operational plasma density and laser parameters for future colliders based on laser-plasma accelerators

    SciTech Connect (OSTI)

    Schroeder, C. B.; Esarey, E.; Leemans, W. P.

    2012-12-21

    The operational plasma density and laser parameters for future colliders based on laser-plasma accelerators are discussed. Beamstrahlung limits the charge per bunch at low plasma densities. Reduced laser intensity is examined to improve accelerator efficiency in the beamstrahlung-limited regime.

  16. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 2, APRIL 2005 Imaging of a Double Helical Structure in the Reversed Field Pinch F. Bonomo, B. E. Chapman, P. Franz, L. Marrelli, P. Martin, P. Piovesan, I. Predebon, G. Spizzo, and R. B. White Abstract-X-ray tomography and Poincaré reconstructions with the ORBIT code allow imaging of coherent structures emerging in a magnetized fusion plasma when chaos in the magnetic field is reduced. Index Terms-Magnetohydrodynamic (MHD), Monte Carlo

  17. Internal field, density & temperature measurements in MTF plasmas using

    Office of Scientific and Technical Information (OSTI)

    Pulsed Polarimetry (Technical Report) | SciTech Connect Technical Report: Internal field, density & temperature measurements in MTF plasmas using Pulsed Polarimetry Citation Details In-Document Search Title: Internal field, density & temperature measurements in MTF plasmas using Pulsed Polarimetry final report Authors: Smith, Roger J. Publication Date: 2014-08-11 OSTI Identifier: 1149491 Report Number(s): 001 DOE Contract Number: SC0002396 Resource Type: Technical Report Research

  18. Relation between plasma plume density and gas flow velocity in atmospheric pressure plasma

    SciTech Connect (OSTI)

    Yambe, Kiyoyuki; Taka, Shogo; Ogura, Kazuo [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)] [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)

    2014-04-15

    We have studied atmospheric pressure plasma generated using a quartz tube, helium gas, and copper foil electrode by applying RF high voltage. The atmospheric pressure plasma in the form of a bullet is released as a plume into the atmosphere. To study the properties of the plasma plume, the plasma plume current is estimated from the difference in currents on the circuit, and the drift velocity is measured using a photodetector. The relation of the plasma plume density n{sub plu}, which is estimated from the current and the drift velocity, and the gas flow velocity v{sub gas} is examined. It is found that the dependence of the density on the gas flow velocity has relations of n{sub plu} ? log(v{sub gas}). However, the plasma plume density in the laminar flow is higher than that in the turbulent flow. Consequently, in the laminar flow, the density increases with increasing the gas flow velocity.

  19. Normal and abnormal evolution of argon metastable density in high-density plasmas

    SciTech Connect (OSTI)

    Seo, B. H.; Kim, J. H.; You, S. J.

    2015-05-15

    A controversial problem on the evolution of Ar metastable density as a function of electron density (increasing trend versus decreasing trend) was resolved by discovering the anomalous evolution of the argon metastable density with increasing electron density (discharge power), including both trends of the metastable density [Daltrini et al., Appl. Phys. Lett. 92, 061504 (2008)]. Later, by virtue of an adequate physical explanation based on a simple global model, both evolutions of the metastable density were comprehensively understood as part of the abnormal evolution occurring at low- and high-density regimes, respectively, and thus the physics behind the metastable evolution has seemed to be clearly disclosed. In this study, however, a remarkable result for the metastable density behavior with increasing electron density was observed: even in the same electron density regime, there are both normal and abnormal evolutions of metastable-state density with electron density depending on the measurement position: The metastable density increases with increasing electron density at a position far from the inductively coupled plasma antenna but decreases at a position close to the antenna. The effect of electron temperature, which is spatially nonuniform in the plasma, on the electron population and depopulation processes of Argon metastable atoms with increasing electron density is a clue to understanding the results. The calculated results of the global model, including multistep ionization for the argon metastable state and measured electron temperature, are in a good agreement with the experimental results.

  20. MIT's Plasma Science Fusion Center: Tokamak Experiments Come Clean about

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Impurity Transport | Princeton Plasma Physics Lab Tokamak Experiments Come Clean about Impurity Transport American Fusion News Category: Massachusetts Institute of Technology (MIT) Link: MIT's Plasma Science Fusion Center: Tokamak Experiments Come Clean about Impurity Transport

  1. Stable laser–plasma accelerators at low densities

    SciTech Connect (OSTI)

    Li, Song; Hafz, Nasr A. M. Mirzaie, Mohammad; Ge, Xulei; Sokollik, Thomas; Chen, Min; Sheng, Zhengming; Zhang, Jie

    2014-07-28

    We report stable laser wakefield acceleration using 17–50 TW laser pulses interacting with 4?mm-long helium gas jet. The initial laser spot size was relatively large (28??m) and the plasma densities were 0.48–2.0?×?10{sup 19?}cm{sup ?3}. High-quality 100–MeV electron beams were generated at the plasma density of 7.5?×?10{sup 18?}cm{sup ?3}, at which the beam parameters (pointing angle, energy spectrum, charge, and divergence angle) were measured and stabilized. At higher densities, filamentation instability of the laser-plasma interaction was observed and it has led to multiple wakefield accelerated electron beams. The experimental results are supported by 2D particle-in-cell simulations. The achievement presented here is an important step toward the use of laser-driven accelerators in real applications.

  2. Plasma ionization frequency, edge-to-axis density ratio, and density on axis of a cylindrical gas discharge

    SciTech Connect (OSTI)

    Palacio Mizrahi, J. H.

    2014-06-15

    A rigorous derivation of expressions, starting from the governing equations, for the ionization frequency, edge-to-axis ratio of plasma density, plasma density at the axis, and radially averaged plasma density in a cylindrical gas discharge has been obtained. The derived expressions are simple and involve the relevant parameters of the discharge: Cylinder radius, axial current, and neutral gas pressure. The found expressions account for ion inertia, ion temperature, and changes in plasma ion collisionality.

  3. On the density limit in the helicon plasma sources

    SciTech Connect (OSTI)

    Kotelnikov, Igor A.

    2014-12-15

    Existence of the density limit in the helicon plasma sources is revisited. The low- and high-frequency regimes of a helicon plasma source operation are distinguished. In the low-frequency regime with ?density limit is deduced from the Golant-Stix criterion of the accessibility of the lower hybrid resonance. In the high-frequency case, ?>?(?{sub ci}?{sub ce}), an appropriate limit is given by the Shamrai-Taranov criterion. Both these criteria are closely related to the phenomenon of the coalescence of the helicon wave with the Trivelpiece-Gould mode. We draw a conclusion that the derived density limits are not currently achieved in existing devices, perhaps, because of high energy cost of gas ionization.

  4. MIT Plasma Science & Fusion Center: research>alcator>research...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Contact Information Physics Research High-Energy- Density Physics Waves & Beams Fusion Technology & Engineering Plasma Technology Useful Links Collaborations at Alcator...

  5. Science Education Programs | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Programs Science Education Student Programs Undergraduates Community College Internship (CCI) National Undergraduate Fellowship Program (NUF) Science Undergraduate Laboratory...

  6. Helicon Plasma Source Configuration Analysis by Means of Density Measurements

    SciTech Connect (OSTI)

    Angrilli, F.; Barber, G.C.; Carter, M.D.; Goulding, R.H.; Maggiora, R.; Pavarin, D.; Sparks, D.O.

    1999-11-13

    Initial results have been obtained from operation of a helicon plasma source built to conduct optimization studies for space propulsion applications. The source features an easily reconfigurable antenna to test different geometries. Operating with He as the source gas, peak densities >= 1.6X10{sup 19} m{sup -3} have been achieved. Radial and axial plasma profiles have been obtained using a microwave interferometer that can be scanned axially and a Langmuir probe. The source will be used to investigate operation at high magnetic field, frequency, and input power.

  7. Science Education Lab | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    control of plasmas, and atmospheric plasmas. Undergraduate and advanced high school students plan all work, formulate research goals, assemble all apparatus, collaborate with...

  8. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density

    Office of Scientific and Technical Information (OSTI)

    Profile at the Plasma Boundary (Conference) | SciTech Connect Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary Citation Details In-Document Search Title: Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary An important aspect of plasma wake field accelerators (PWFA) is stable propagation of the drive beam. In the under dense plasma regime, the drive beam creates an ion channel which acts on

  9. DOE New Jersey Regional Middle School Science Bowl | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab 0, 2015, 9:00am to 3:00pm Science Education Lab-wide DOE New Jersey Regional Middle School Science Bowl Contact Information Website: New Jersey Regional Science Bowl Coordinator(s): Deedee Ortiz-Arias, Science Education Department Program Administraor dortiz@pppl.gov PPPL Entrance Procedures Visitor Information, Directions, Security at PPPL As a federal facility, the Princeton Plasma Physics Laboratory is operating under heightened security measures because of the events of

  10. Effects of argon gas pressure on its metastable-state density in high-density plasmas

    SciTech Connect (OSTI)

    Seo, B. H.; Kim, J. H.; You, S. J.

    2015-05-15

    The effect of argon gas pressure on its metastable density in inductively coupled plasmas (ICPs) is investigated by using the laser-induced fluorescence method. Our results show that the metastable-state density of argon varies with the gas pressure depending on the measurement position; the density decreases with the pressure at a position far from the ICP antenna, whereas it increases with the pressure at a position near the antenna. This contrast in the metastable-state density trend with the pressure is explained by considering the electron temperature variations at the two measurement positions. The theoretical interpretation and calculation using a global model are also addressed in detail in this paper.

  11. Science Education Group | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Education Group View larger image Sci Ed Group 15 View larger image Group 21

  12. The expansion of a collisionless plasma into a plasma of lower density

    SciTech Connect (OSTI)

    Perego, M.; Gunzburger, M. D.; Howell, P. D.; Ockendon, J. R.; Allen, J. E.

    2013-05-15

    This paper considers the asymptotic and numerical solution of a simple model for the expansion of a collisionless plasma into a plasma of lower density. The dependence on the density ratio of qualitative and quantitative features of solutions of the well-known cold-ion model is explored. In the cold-ion limit, we find that a singularity develops in the ion density in finite time unless the density ratio is zero or close to unity. The classical cold-ion model may cease to be valid when such a singularity occurs and we then regularize the model by the finite ion-temperature Vlasov-Poisson system. Numerical evidence suggests the emergence of a multi-modal velocity distribution.

  13. 2012 APS-DPP Plasma Science Expo, Providence, RI | Princeton...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    APS-DPP Plasma Science Expo, Providence, RI View larger image IMG 1847 View larger image IMG 1598 View larger image IMG 1608 View larger image IMG 1609 View larger image IMG 1614...

  14. Plasmas, Dielectrics and the Ultrafast: First Science and Operational

    Office of Scientific and Technical Information (OSTI)

    Experience at FACET (Conference) | SciTech Connect Conference: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET Citation Details In-Document Search Title: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET FACET (Facility for Advanced Accelerator and Experimental Tests) is an accelerator R&D test facility that has been recently constructed at SLAC National Accelerator Laboratory. The facility provides 20 GeV,

  15. Plasmas, Dielectrics and the Ultrafast: First Science and Operational

    Office of Scientific and Technical Information (OSTI)

    Experience at FACET (Conference) | SciTech Connect Conference: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET Citation Details In-Document Search Title: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET FACET (Facility for Advanced Accelerator and Experimental Tests) is an accelerator R&D test facility that has been recently constructed at SLAC National Accelerator Laboratory. The facility provides 20 GeV,

  16. Science Education | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    About Blog Programs Galleries Upcoming Events Lab Outreach Efforts Graduate Programs Off Site University Research (OSUR) Organization Contact Us Science Education About Blog Programs Galleries Upcoming Events Lab Outreach Efforts Graduate Programs Off Site University Research (OSUR) Science Education Join us on January 9, 2016, for the Ronald E. Hatcher Science on Saturday Lecture Series! The 2016 Ronald E. Hatcher Science on Saturday Lecture Series is set to begin on January 9, 2016. Dr. Alan

  17. DOE's NJ HIGH SCHOOL SCIENCE BOWL® | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    5, 2012 (All day) Science Education MBG Auditorium DOE's NJ HIGH SCHOOL SCIENCE BOWL® DOE's NJ HIGH SCHOOL SCIENCE BOWL® PPPL Entrance Procedures Visitor Information, Directions, Security at PPPL As a federal facility, the Princeton Plasma Physics Laboratory is operating under heightened security measures because of the events of September 11, 2001. Upon arrival at PPPL, adult visitors must show a government-issued photo I.D. - for example, a passport or a driver's license. Non-U.S. citizens

  18. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density

    Office of Scientific and Technical Information (OSTI)

    Profile at the Plasma Boundary (Conference) | SciTech Connect Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary Citation Details In-Document Search Title: Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary Ă— You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is

  19. About Science Education | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    About Science Education Our Mission Using the human, scientific, and technological resources of PPPL, our mission is to: Provide opportunities for students and teachers to engage in scientific inquiry in ways that enhance their understanding of science concepts and scientific ways of thinking. Provide innovative opportunities for educators to work together and with scientists and engineers to enhance science teaching and learning. Reach out to all students and teachers, particularly those

  20. Exploring Plasma Science Advances from Fusion Findings to Astrophysical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Achievements | Princeton Plasma Physics Lab Exploring Plasma Science Advances from Fusion Findings to Astrophysical Achievements By John Greenwald December 4, 2012 Tweet Widget Google Plus One Share on Facebook The latest advances in plasma physics were the focus of more than 1,000 scientists from around the world who gathered in Providence, R.I., from Oct. 29 through Nov. 2 for the 54th Annual Meeting of the American Physical Society's Division of Plasma Physics (APS-DPP). Papers, posters

  1. Princeton Plasma Physics Lab - Science literacy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    science-literacy Having the knowledge and understanding of scientific concepts and processes necessary to make informed decisions on scientific issues. en COLLOQUIUM: Chance,...

  2. Science Education | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    activities with science education programs to create a center of excellence for students, teachers and the general public. We contribute to the training of the next...

  3. Science Education Upcoming Events | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Upcoming Events January 9, 2016 January 9, 2016, 9:30am January 9, 2016: Science on Saturday: Dr. Alan Hirshfeld: Starlight Detectives: How Astronomers, Inventors, and Eccentrics...

  4. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the average electronic thermal diffusivity in the region of the plasma where the pulse prop- agates. A model of diffusive heat propagation in a cylinder is under development and...

  5. Advances and Challenges in Computational Plasma Science

    SciTech Connect (OSTI)

    W.M. Tang; V.S. Chan

    2005-01-03

    Scientific simulation, which provides a natural bridge between theory and experiment, is an essential tool for understanding complex plasma behavior. Recent advances in simulations of magnetically-confined plasmas are reviewed in this paper with illustrative examples chosen from associated research areas such as microturbulence, magnetohydrodynamics, and other topics. Progress has been stimulated in particular by the exponential growth of computer speed along with significant improvements in computer technology.

  6. The National Ignition Facility: Ushering in a new age for high energy density science

    SciTech Connect (OSTI)

    Moses, E. I.; Boyd, R. N.; Remington, B. A.; Keane, C. J.; Al-Ayat, R.

    2009-04-15

    The National Ignition Facility (NIF) [E. I. Moses, J. Phys.: Conf. Ser. 112, 012003 (2008); https://lasers.llnl.gov/], completed in March 2009, is the highest energy laser ever constructed. The high temperatures and densities achievable at NIF will enable a number of experiments in inertial confinement fusion and stockpile stewardship, as well as access to new regimes in a variety of experiments relevant to x-ray astronomy, laser-plasma interactions, hydrodynamic instabilities, nuclear astrophysics, and planetary science. The experiments will impact research on black holes and other accreting objects, the understanding of stellar evolution and explosions, nuclear reactions in dense plasmas relevant to stellar nucleosynthesis, properties of warm dense matter in planetary interiors, molecular cloud dynamics and star formation, and fusion energy generation.

  7. Modeling of free electronic state density in hydrogenic plasmas based on nearest neighbor approximation

    SciTech Connect (OSTI)

    Nishikawa, Takeshi

    2014-07-15

    Most conventional atomic models in a plasma do not treat the effect of the plasma on the free-electron state density. Using a nearest neighbor approximation, the state densities in hydrogenic plasmas for both bound and free electrons were evaluated and the effect of the plasma on the atomic model (especially for the state density of the free electron) was studied. The model evaluates the electron-state densities using the potential distribution formed by the superposition of the Coulomb potentials of two ions. The potential from one ion perturbs the electronic state density on the other. Using this new model, one can evaluate the free-state density without making any ad-hoc assumptions. The resulting contours of the average ionization degree, given as a function of the plasma temperature and density, are shifted slightly to lower temperatures because of the effect of the increasing free-state density.

  8. Exploration of Plasma Jets Approach to High Energy Density Physics. Final report

    SciTech Connect (OSTI)

    Chen, Chiping

    2013-08-26

    High-energy-density laboratory plasma (HEDLP) physics is an emerging, important area of research in plasma physics, nuclear physics, astrophysics, and particle acceleration. While the HEDLP regime occurs at extreme conditions which are often found naturally in space but not on the earth, it may be accessible by colliding high intensity plasmas such as high-energy-density plasma jets, plasmoids or compact toroids from plasma guns. The physics of plasma jets is investigated in the context of high energy density laboratory plasma research. This report summarizes results of theoretical and computational investigation of a plasma jet undergoing adiabatic compression and adiabatic expansion. A root-mean-squared (rms) envelope theory of plasma jets is developed. Comparison between theory and experiment is made. Good agreement between theory and experiment is found.

  9. Science on Saturday: Plastic Electronics | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    February 6, 2016, 9:30am Science On Saturday MBG Auditorium, PPPL Science on Saturday: Plastic Electronics Professor Lynn Loo Princeton University Abstract: PDF icon 05 Loo.pdf Science_on_Saturday06Feb2016_LLoo Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov Host(s): Dr. Andrew Zwicker azwicker@pppl.gov PPPL Entrance Procedures Visitor Information, Directions, Security at PPPL As a federal facility, the Princeton Plasma Physics Laboratory is operating under heightened

  10. Fusion and Plasmas | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Fusion and Plasmas Fusion Energy Sciences (FES) FES Home About Organization Chart .pdf ... Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy ...

  11. 2012 Science Bowls | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Bowls View larger image IMG 0357 View larger image IMG 0358 View larger image IMG 0359 View larger image IMG 0360 View larger image IMG 0361 View larger image IMG 0362 View larger image IMG 0363 View larger image IMG 0365 View larger image IMG 0368 View larger image IMG 0369 View larger image IMG 0370 View larger image IMG 0371 View larger image IMG 0376 View larger image IMG 0378 View larger image IMG 0379 View larger image IMG 0381 View larger image IMG 0382 View larger image IMG 0394

  12. High Energy Density Laboratory Plasmas Program | National Nuclear...

    National Nuclear Security Administration (NNSA)

    density physics (HEDP). An interagency task force report identified four research categories within the field of HEDP: astrophysics, high energy density nuclear physics, high ...

  13. Assessment of plasma impedance probe for measuring electron density and collision frequency in a plasma with spatial and temporal gradients

    SciTech Connect (OSTI)

    Hopkins, Mark A. King, Lyon B.

    2014-05-15

    Numerical simulations and experimental measurements were combined to determine the ability of a plasma impedance probe (PIP) to measure plasma density and electron collision frequency in a plasma containing spatial gradients as well as time-varying oscillations in the plasma density. A PIP is sensitive to collision frequency through the width of the parallel resonance in the Re[Z]-vs.-frequency characteristic, while also being sensitive to electron density through the zero-crossing of the Im[Z]-vs.-frequency characteristic at parallel resonance. Simulations of the probe characteristic in a linear plasma gradient indicated that the broadening of Re[Z] due to the spatial gradient obscured the broadening due to electron collision frequency, preventing a quantitative measurement of the absolute collision frequency for gradients considered in this study. Simulation results also showed that the PIP is sensitive to relative changes in electron collision frequency in a spatial density gradient, but a second broadening effect due to time-varying oscillations made collision frequency measurements impossible. The time-varying oscillations had the effect of causing multiple zero-crossings in Im[Z] at parallel resonance. Results of experiments and simulations indicated that the lowest-frequency zero-crossing represented the lowest plasma density in the oscillations and the highest-frequency zero-crossing represented the highest plasma density in the oscillations, thus the PIP probe was found to be an effective tool to measure both the average plasma density as well as the maximum and minimum densities due to temporal oscillations.

  14. Metrology Challenges for High Energy Density Science Target Manufacture

    SciTech Connect (OSTI)

    Seugling, R M; Bono, M J; Davis, P

    2009-02-19

    Currently, High Energy Density Science (HEDS) experiments are used to support and qualify predictive physics models. These models assume ideal conditions such as energy (input) and device (target) geometry. The experiments rely on precision targets constructed from components with dimensions in the millimeter range, while having micrometer-scale, functional features, including planar steps, sine waves, and step-joint geometry on hemispherical targets. Future target designs will likely have features and forms that rival or surpass current manufacturing and characterization capability. The dimensional metrology of these features is important for a number of reasons, including qualification of sub-components prior to assembly, quantification of critical features on the as-built assemblies and as a feedback mechanism for fabrication process development. Variations in geometry from part to part can lead to functional limitations, such as unpredictable instabilities during an experiment and the inability to assemble a target from poorly matched sub-components. Adding to the complexity are the large number and variety of materials, components, and shapes that render any single metrology technique difficult to use with low uncertainty. Common materials include metal and glass foams, doped transparent and opaque plastics and a variety of deposited and wrought metals. A suite of metrology tools and techniques developed to address the many critical issues relevant to the manufacture of HEDS targets including interferometry, x-ray radiography and contact metrology are presented including two sided interferometry for absolute thickness metrology and low force probe technology for micrometer feature coordinate metrology.

  15. High-efficiency acceleration in the laser wakefield by a linearly increasing plasma density

    SciTech Connect (OSTI)

    Dong, Kegong; Wu, Yuchi; Zhu, Bin; Zhang, Zhimeng; Zhao, Zongqing; Zhou, Weimin; Hong, Wei; Cao, Leifeng; Gu, Yuqiu

    2014-12-15

    The acceleration length and the peak energy of the electron beam are limited by the dephasing effect in the laser wakefield acceleration with uniform plasma density. Based on 2D-3V particle in cell simulations, the effects of a linearly increasing plasma density on the electron acceleration are investigated broadly. Comparing with the uniform plasma density, because of the prolongation of the acceleration length and the gradually increasing accelerating field due to the increasing plasma density, the electron beam energy is twice higher in moderate nonlinear wakefield regime. Because of the lower plasma density, the linearly increasing plasma density can also avoid the dark current caused by additional injection. At the optimal acceleration length, the electron energy can be increased from 350 MeV (uniform) to 760 MeV (linearly increasing) with the energy spread of 1.8%, the beam duration is 5 fs and the beam waist is 1.25 μm. This linearly increasing plasma density distribution can be achieved by a capillary with special gas-filled structure, and is much more suitable for experiment.

  16. Influence of microwave driver coupling design on plasma density at Testbench for Ion sources Plasma Studies, a 2.45 GHz Electron Cyclotron Resonance Plasma Reactor

    SciTech Connect (OSTI)

    Megía-Macías, A.; Vizcaíno-de-Julián, A.; Cortázar, O. D.

    2014-03-15

    A comparative study of two microwave driver systems (preliminary and optimized) for a 2.45 GHz hydrogen Electron Cyclotron Resonance plasma generator has been conducted. The influence on plasma behavior and parameters of stationary electric field distribution in vacuum, i.e., just before breakdown, along all the microwave excitation system is analyzed. 3D simulations of resonant stationary electric field distributions, 2D simulations of external magnetic field mapping, experimental measurements of incoming and reflected power, and electron temperature and density along the plasma chamber axis have been carried out. By using these tools, an optimized set of plasma chamber and microwave coupler has been designed paying special attention to the optimization of stationary electric field value in the center of the plasma chamber. This system shows a strong stability on plasma behavior allowing a wider range of operational parameters and even sustaining low density plasma formation without external magnetic field. In addition, the optimized system shows the capability to produce values of plasma density four times higher than the preliminary as a consequence of a deeper penetration of the magnetic resonance surface in relative high electric field zone by keeping plasma stability. The increment of the amount of resonance surface embedded in the plasma under high electric field is suggested as a key factor.

  17. Stationary self-focusing of intense laser beam in cold quantum plasma using ramp density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2012-10-15

    By using a transient density profile, we have demonstrated stationary self-focusing of an electromagnetic Gaussian beam in cold quantum plasma. The paper is devoted to the prospects of using upward increasing ramp density profile of an inhomogeneous nonlinear medium with quantum effects in self-focusing mechanism of high intense laser beam. We have found that the upward ramp density profile in addition to quantum effects causes much higher oscillation and better focusing of laser beam in cold quantum plasma in comparison to that in the classical relativistic case. Our computational results reveal the importance and influence of formation of electron density profiles in enhancing laser self-focusing.

  18. Energy density dependence of hydrogen combustion efficiency in atmospheric pressure microwave plasma

    SciTech Connect (OSTI)

    Yoshida, T.; Ezumi, N.; Sawada, K.; Tanaka, Y.; Tanaka, M.; Nishimura, K.

    2015-03-15

    The recovery of tritium in nuclear fusion plants is a key issue for safety. So far, the oxidation procedure using an atmospheric pressure plasma is expected to be part of the recovery method. In this study, in order to clarify the mechanism of hydrogen oxidation by plasma chemistry, we have investigated the dependence of hydrogen combustion efficiency on gas flow rate and input power in the atmospheric pressure microwave plasma. It has been found that the combustion efficiency depends on energy density of absorbed microwave power. Hence, the energy density is considered as a key parameter for combustion processes. Also neutral gas temperatures inside and outside the plasma were measured by an optical emission spectroscopy method and thermocouple. The result shows that the neutral gas temperature in the plasma is much higher than the outside temperature of plasma. The high neutral gas temperature may affect the combustion reaction. (authors)

  19. Independent control of electron energy and density using a rotating magnetic field in inductively coupled plasmas

    SciTech Connect (OSTI)

    Kondo, Takahiro; Ohta, Masayuki; Ito, Tsuyohito; Okada, Shigefumi

    2013-09-21

    Effects of a rotating magnetic field (RMF) on the electron energy distribution function (EEDF) and on the electron density are investigated with the aim of controlling the radical composition of inductively coupled plasmas. By adjusting the RMF frequency and generation power, the desired electron density and electron energy shift are obtained. Consequently, the amount and fraction of high-energy electrons, which are mostly responsible for direct dissociation processes of raw molecules, will be controlled externally. This controllability, with no electrode exposed to plasma, will enable us to control radical components and their flux during plasma processing.

  20. Effect of secondary emission on the argon plasma afterglow with large dust density

    SciTech Connect (OSTI)

    Denysenko, I. B.; Azarenkov, N. A.; Burmaka, G. P.; Stefanovi?, I.

    2015-02-15

    A zero-dimensional, space-averaged model for argon plasma afterglow with large dust density is developed. In the model, three groups of electrons in the plasma afterglow are assumed: (i) thermal electrons with Maxwellian distribution, (ii) energetic electrons generated by metastable-metastable collisions (metastable pooling), and (iii) secondary electrons generated at collisions of ions with the electrodes, which have sufficiently large negative voltages in the afterglow. The model calculates the time-dependencies for electron densities in plasma afterglow based on experimental decay times for metastable density and electrode bias. The effect of secondary emission on electron density in the afterglow is estimated by varying secondary emission yields. It is found that this effect is less important than metastable pooling. The case of dust-free plasma afterglow is considered also, and it is found that in the afterglow the effect of secondary emission may be more important than metastable pooling. The secondary emission may increase thermal electron density n{sub e} in dust-free and dusty plasma afterglows on a few ten percentages. The calculated time dependencies for n{sub e} in dust-free and dusty plasma afterglows describe well the experimental results.

  1. Device and method for electron beam heating of a high density plasma

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high density plasma in a small localized region. A relativistic electron beam generator produces a high voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target plasma is ionized prior to application of the electron beam by means of a laser or other preionization source. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region within the high density plasma target.

  2. A new method for determining the plasma electron density using optical frequency comb interferometer

    SciTech Connect (OSTI)

    Arakawa, Hiroyuki Tojo, Hiroshi; Sasao, Hajime; Kawano, Yasunori; Itami, Kiyoshi

    2014-04-15

    A new method of plasma electron density measurement using interferometric phases (fractional fringes) of an optical frequency comb interferometer is proposed. Using the characteristics of the optical frequency comb laser, high density measurement can be achieved without fringe counting errors. Simulations show that the short wavelength and wide wavelength range of the laser source and low noise in interferometric phases measurements are effective to reduce ambiguity of measured density.

  3. On the breaking of a plasma wave in a thermal plasma. I. The structure of the density singularity

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi; Bulanov, Stepan S.; Schroeder, Carl B.; Esarey, Eric; Califano, Francesco; Pegoraro, Francesco

    2012-11-15

    The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wave breaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical 'peakon' form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions. The after-wavebreak regime is then examined, and a semi-analytical model of the density evolution is constructed. Finally the results of two dimensional particle in cell simulations for different initial electron distribution functions are compared, and the role of thermal effects in enhancing particle injection is noted.

  4. Controlling Plasmas for a Cleaner World | U.S. DOE Office of Science (SC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Controlling Plasmas for a Cleaner World Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584 E: Email Us More Information » 10.01.12 Controlling Plasmas for a Cleaner World New

  5. The impact of Hall physics on magnetized high energy density plasma jets

    SciTech Connect (OSTI)

    Gourdain, P.-A.; Seyler, C. E.; Atoyan, L.; Greenly, J. B.; Hammer, D. A.; Kusse, B. R.; Pikuz, S. A.; Potter, W. M.; Schrafel, P. C.; Shelkovenko, T. A.

    2014-05-15

    Hall physics is often neglected in high energy density plasma jets due to the relatively high electron density of such jets (n{sub e}???10{sup 19}?cm{sup ?3}). However, the vacuum region surrounding the jet has much lower densities and is dominated by Hall electric field. This electric field redirects plasma flows towards or away from the axis, depending on the radial current direction. A resulting change in the jet density has been observed experimentally. Furthermore, if an axial field is applied on the jet, the Hall effect is enhanced and ignoring it leads to serious discrepancies between experimental results and numerical simulations. By combining high currents (?1 MA) and magnetic field helicity (15° angle) in a pulsed power generator such as COBRA, plasma jets can be magnetized with a 10?T axial field. The resulting field enhances the impact of the Hall effect by altering the density profile of current-free plasma jets and the stability of current-carrying plasma jets (e.g., Z-pinches)

  6. LOCALIZED PLASMA DENSITY ENHANCEMENTS OBSERVED IN STEREO COR1

    SciTech Connect (OSTI)

    Jones, Shaela I.; Davila, Joseph M.

    2009-08-20

    Measurements of solar wind speed in the solar corona, where it is primarily accelerated, have proven elusive. One of the more successful attempts has been the tracking of outward-moving density inhomogeneities in white-light coronagraph images. These inhomogeneities, or 'blobs', have been treated as passive tracers of the ambient solar wind. Here we report on the extension of these observations to lower altitudes using the STEREO COR1 coronagraph, and discuss the implications of these measurements for theories about the origin of these features.

  7. Investigation of physical processes limiting plasma density in H-mode on DIII-D

    SciTech Connect (OSTI)

    Maingi, R.; Mahdavi, M.A.; Jernigan, T.C.

    1996-12-01

    A series of experiments was conducted on the DIII-D tokamak to investigate the physical processes which limit density in high confinement mode (H-mode) discharges. The typical H-mode to low confinement mode (L-mode) transition limit at high density near the empirical Greenwald density limit was avoided by divertor pumping, which reduced divertor neutral pressure and prevented formation of a high density, intense radiation zone (MARFE) near the X-point. It was determined that the density decay time after pellet injection was independent of density relative to the Greenwald limit and increased non-linearly with the plasma current. Magnetohydrodynamic (MHD) activity in pellet-fueled plasmas was observed at all power levels, and often caused unacceptable confinement degradation, except when the neutral beam injected (NBI) power was {le} 3 MW. Formation of MARFEs on closed field lines was avoided with low safety factor (q) operation but was observed at high q, qualitatively consistent with theory. By using pellet fueling and optimizing discharge parameters to avoid each of these limits, an operational space was accessed in which density {approximately} 1.5 {times} Greenwald limit was achieved for 600 ms, and good H-mode confinement was maintained for 300 ms of the density flattop. More significantly, the density was successfully increased to the limit where a central radiative collapse was observed, the most fundamental density limit in tokamaks.

  8. 2012 APS-DPP Plasma Science Expo, Providence, RI | Princeton Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lab APS-DPP Plasma Science Expo, Providence, RI View larger image IMG 1847 View larger image IMG 1598 View larger image IMG 1608 View larger image IMG 1609 View larger image IMG 1614 View larger image IMG 1647 View larger image IMG 1650 View larger image IMG 1651 View larger image IMG 1657 View larger image IMG 1659 View larger image IMG 1662 View larger image IMG 1663 View larger image IMG 1664 View larger image IMG 1668 View larger image IMG 1672 View larger image IMG 1675 View larger

  9. Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel

    SciTech Connect (OSTI)

    Sati, Priti; Tripathi, V. K.

    2012-12-15

    Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

  10. Strong self-focusing of a cosh-Gaussian laser beam in collisionless magneto-plasma under plasma density ramp

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti

    2014-07-15

    The effect of plasma density ramp on self-focusing of cosh-Gaussian laser beam considering ponderomotive nonlinearity is analyzed using WKB and paraxial approximation. It is noticed that cosh-Gaussian laser beam focused earlier than Gaussian beam. The focusing and de-focusing nature of the cosh-Gaussian laser beam with decentered parameter, intensity parameter, magnetic field, and relative density parameter has been studied and strong self-focusing is reported. It is investigated that decentered parameter “b” plays a significant role for the self-focusing of the laser beam as for b=2.12, strong self-focusing is seen. Further, it is observed that extraordinary mode is more prominent toward self-focusing rather than ordinary mode of propagation. For b=2.12, with the increase in the value of magnetic field self-focusing effect, in case of extraordinary mode, becomes very strong under plasma density ramp. Present study may be very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, and x-ray lasers. Moreover, plasma density ramp plays a vital role to enhance the self-focusing effect.

  11. Effect of the resonant growth of harmonics on the electron density in capacitively coupled plasma

    SciTech Connect (OSTI)

    Yamazawa, Yohei

    2009-11-09

    The growth of harmonics is known to occur under the condition of plasma series resonance (PSR). In an actual plasma process chamber, the external circuit also affects the PSR. We experimentally demonstrated the resonant growth of the third and fourth harmonics by tuning a variable capacitor attached to the electrode, and investigated the influence of the growth on the electron density. We observed significant increases in electron density as the amplitude of harmonics grows. The result clearly shows that nonlinear electron resonance heating actually takes place.

  12. Inhomogeneities of plasma density and electric field as sources of electrostatic turbulence in the auroral region

    SciTech Connect (OSTI)

    Ilyasov, Askar A.; Chernyshov, Alexander A. Mogilevsky, Mikhail M.; Golovchanskaya, Irina V. Kozelov, Boris V.

    2015-03-15

    Inhomogeneities of plasma density and non-uniform electric fields are compared as possible sources of a sort of electrostatic ion cyclotron waves that can be identified with broadband extremely low frequency electrostatic turbulence in the topside auroral ionosphere. Such waves are excited by inhomogeneous energy-density-driven instability. To gain a deeper insight in generation of these waves, computational modeling is performed with various plasma parameters. It is demonstrated that inhomogeneities of plasma density can give rise to this instability even in the absence of electric fields. By using both satellite-observed and model spatial distributions of plasma density and electric field in our modeling, we show that specific details of the spatial distributions are of minor importance for the wave generation. The solutions of the nonlocal inhomogeneous energy-density-driven dispersion relation are investigated for various ion-to-electron temperature ratios and directions of wave propagation. The relevance of the solutions to the observed spectra of broadband extremely low frequency emissions is shown.

  13. Power balance in a high-density field reversed configuration plasma

    SciTech Connect (OSTI)

    Renneke, R. M.; Intrator, T. P.; Hsu, S. C.; Wurden, G. A.; Waganaar, W. J.; Ruden, E. L.; Grabowski, T. C.

    2008-06-15

    A global power balance analysis has been performed for the Field Reversed Experiment with Liner high density (>5x10{sup 22} m{sup -3}) field reversed configuration (FRC) plasma. The analysis was based on a zero-dimensional power balance model [D. J. Rey and M. Tuszewski, Phys. Fluids 27, 1514 (1984)]. The key findings are as follows. First, the percentage of radiative losses relative to total loss is an order of magnitude lower than previous lower density FRC experiments. Second, Ohmic heating was found to correlate with the poloidal flux trapping at FRC formation, suggesting that poloidal flux dissipation is primarily responsible for plasma heating. Third, high density FRCs analyzed in this work reinforce the low-density adiabatic scaling, which shows that particle confinement time and flux confinement time are approximately equal.

  14. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Technology Useful Links Presentations from the 45th Annual Meeting of the APS Division of Plasma Physics, Albuquerque, 2003 Invited Orals D. Ernst Role of Trapped...

  15. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & Engineering Plasma Technology Waves & Beams Useful Links 49th Annual Meeting of the APS Division of Plasma Physics, Orlando, 2007 Invited Orals P. Bonoli Lower Hybrid Current...

  16. Multispecies density peaking in gyrokinetic turbulence simulations of low collisionality Alcator C-Mod plasmas

    SciTech Connect (OSTI)

    Mikkelsen, D. R. Bitter, M.; Delgado-Aparicio, L.; Hill, K. W.; Greenwald, M.; Howard, N. T.; Hughes, J. W.; Rice, J. E.; Reinke, M. L.; Podpaly, Y.; Ma, Y.; Candy, J.; Waltz, R. E.

    2015-06-15

    Peaked density profiles in low-collisionality AUG and JET H-mode plasmas are probably caused by a turbulently driven particle pinch, and Alcator C-Mod experiments confirmed that collisionality is a critical parameter. Density peaking in reactors could produce a number of important effects, some beneficial, such as enhanced fusion power and transport of fuel ions from the edge to the core, while others are undesirable, such as lower beta limits, reduced radiation from the plasma edge, and consequently higher divertor heat loads. Fundamental understanding of the pinch will enable planning to optimize these impacts. We show that density peaking is predicted by nonlinear gyrokinetic turbulence simulations based on measured profile data from low collisionality H-mode plasma in Alcator C-Mod. Multiple ion species are included to determine whether hydrogenic density peaking has an isotope dependence or is influenced by typical levels of low-Z impurities, and whether impurity density peaking depends on the species. We find that the deuterium density profile is slightly more peaked than that of hydrogen, and that experimentally relevant levels of boron have no appreciable effect on hydrogenic density peaking. The ratio of density at r/a?=?0.44 to that at r/a?=?0.74 is 1.2 for the majority D and minority H ions (and for electrons), and increases with impurity Z: 1.1 for helium, 1.15 for boron, 1.3 for neon, 1.4 for argon, and 1.5 for molybdenum. The ion temperature profile is varied to match better the predicted heat flux with the experimental transport analysis, but the resulting factor of two change in heat transport has only a weak effect on the predicted density peaking.

  17. U.S. Department of Energy's Plasma Science Center holds third annual

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    meeting at PPPL | Princeton Plasma Physics Lab Department of Energy's Plasma Science Center holds third annual meeting at PPPL By John Greenwald May 22, 2012 Tweet Widget Google Plus One Share on Facebook Jeff Walker, a University of West Virginia graduate student, discussed his poster on dusty plasmas with PPPL physicist Erik Gilson. (Photo by Elle Starkman, PPPL Office of Communications) Jeff Walker, a University of West Virginia graduate student, discussed his poster on dusty plasmas

  18. Organization by Gordon Research Conferences of the 2012 Plasma Processing Science Conference 22-27 July 2012

    SciTech Connect (OSTI)

    Jane Chang

    2012-07-27

    The 2012 Gordon Research Conference on Plasma Processing Science will feature a comprehensive program that will highlight the most cutting edge scientific advances in plasma science and technology as well as explore the applications of this nonequilibrium medium in possible approaches relative to many grand societal challenges. Fundamental science sessions will focus on plasma kinetics and chemistry, plasma surface interactions, and recent trends in plasma generation and multi-phase plasmas. Application sessions will explore the impact of plasma technology in renewable energy, the production of fuels from renewable feedstocks and carbon dioxide neutral solar fuels (from carbon dioxide and water), and plasma-enabled medicine and sterilization.

  19. Effect of electron density profile on power absorption of high frequency electromagnetic waves in plasma

    SciTech Connect (OSTI)

    Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2012-07-15

    Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.

  20. Laser Plasma Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser Plasma Interactions Laser Plasma Interactions Understanding and controlling laser produced plasmas for fusion and basic science Contact David Montgomery (505) 665-7994 Email John Kline (505) 667-7062 Email Thomson scattering is widely used to measure plasma temperature, density, and flow velocity in laser-produced plasmas at Trident, and is also used to detect plasma waves driven by unstable and nonlinear processes. A typical configuration uses a low intensity laser beam (2nd, 3rd, or 4th

  1. Scattering of electromagnetic waves by vortex density structures associated with interchange instability: Analytical and large scale plasma simulation results

    SciTech Connect (OSTI)

    Sotnikov, V.; Kim, T.; Lundberg, J.; Paraschiv, I.; Mehlhorn, T. A.

    2014-05-15

    The presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma density irregularities in the form of coherent vortex structures. Interchange or flute type density irregularities in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play an important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, in high energy density physics, and in many other applications. We will discuss scattering of high frequency electromagnetic waves on low frequency density irregularities due to the presence of vortex density structures associated with interchange instability. We will also present particle-in-cell simulation results of electromagnetic scattering on vortex type density structures using the large scale plasma code LSP and compare them with analytical results.

  2. Applying physics, teamwork to fusion energy science | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab Applying physics, teamwork to fusion energy science American Fusion News Category: Massachusetts Institute of Technology (MIT) Link: Applying physics, teamwork to fusion energy science

  3. A scheme to produce high density and high temperature plasma for opacity measurement

    SciTech Connect (OSTI)

    Xu, Yan; Wu, SiZhong; Zheng, WuDi

    2015-04-15

    The opacity of shock-compressed material is of general scientific interest for astrophysical plasmas and for inertial confinement fusion research. A proposal is suggested to produce high temperature plasma with density around 1?g/cm{sup ?3}. Two types of opacity target (the sandwich target and the foam enhanced sandwich target) are investigated numerically. The foam enhanced sandwich target has structure of foam–solid-sample-solid-foam. The foam will increase laser absorption efficiency and the ablating pressure. Hydrodynamic simulations confirm that the laser can be fully absorbed by the under-critical-density foam and a faster shock is produced inside the CH layer. High intensity lasers heat opacity target from both sides. The CH layers must be thick enough to keep the laser away from the sample. The laser-driven shocks move inward and collide at the center. Part of their kinetic energy is converted into internal energy and high density and high temperature local thermodynamic equilibrium sample plasma is produced. The plasma produced by laser heating the foam enhanced sandwich target has higher sample temperature than by laser heating the sandwich target. It may be useful for measuring the opacity of shock compressed material in laboratory.

  4. Modelling of the internal dynamics and density in a tens of joules plasma focus device

    SciTech Connect (OSTI)

    Marquez, Ariel; Gonzalez, Jose; Tarifeno-Saldivia, Ariel; Pavez, Cristian; Soto, Leopoldo; Clausse, Alejandro

    2012-01-15

    Using MHD theory, coupled differential equations were generated using a lumped parameter model to describe the internal behaviour of the pinch compression phase in plasma focus discharges. In order to provide these equations with appropriate initial conditions, the modelling of previous phases was included by describing the plasma sheath as planar shockwaves. The equations were solved numerically, and the results were contrasted against experimental measurements performed on the device PF-50J. The model is able to predict satisfactorily the timing and the radial electron density profile at the maximum compression.

  5. Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

    SciTech Connect (OSTI)

    Jung Yu, Dae; Kim, Kihong

    2013-12-15

    We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

  6. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Lower Hybrid Wave Propagation in the Edge Plasma of a Tokamak D. Brunner Plasma Sheath Heat Flux Transmission in the Alcator C-Mod Divertor M. Garrett ICRF Antenna Design...

  7. MIT Plasma Science & Fusion Center: research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research Program Information Publications & News Meetings & Seminars Contact Information Physics Research Fusion Technology & Engineering Plasma Technology Waves & Beams Useful...

  8. Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

    SciTech Connect (OSTI)

    Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R.

    2006-12-04

    Conventional wisdom assigns the DC glow discharge regime to plasma currents below {approx}500 mA values, beyond which the discharge falls into the anomalous glow and the turbulent arc regimes. However, we have found evidence that, during toroidal discharges, this barrier can be ostensibly extended up to 800 mA. Thus, a computer simulation has been applied to the evolution of the main electrical characteristics of such a glow discharge plasma in a toroidal vessel in order to design and construct a respective voltage/current controlled source. This should be able to generate a DC plasma in the glow regime with which currents in the range 10-3-100 A can be experimented and 109-1010 cm-3 plasma densities can be achieved to PIII optimization purposes. The plasma is modelled as a voltage-controlled current source able to be turned on whenever the breakdown voltage is reached across the gap between the anode and the vessel wall. The simulation outcome fits well our experimental measurements showing that the plasma current obeys power laws that are dependent on the power current and other control variables such as the gas pressure.

  9. Science On Saturday Archive | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Upcoming Events Events Calendar Colloquia Archive Science On Saturday Archive Research Education Organization Contact Us Upcoming Events Events Calendar Colloquia Archive Science On Saturday Archive Science On Saturday Archive Science on Saturday: Taking the Universe's Baby Picture March 12, 2016 Professor David Spergel Princeton University Science on Saturday: Reimagining the Possible: Scientific Transformations Shaping the Path Towards Fusion Energy March 5, 2016 Dr. Edmund Synakowski

  10. Experimental and Computational Studies of High Energy Density Plasma Streams Ablated from Fine Wires

    SciTech Connect (OSTI)

    Greenly, John B.; Seyler, Charles

    2014-03-30

    Experimental and computational studies of high energy density plasma streams ablated from fine wires. Laboratory of Plasma Studies, School of Electrical and Computer Engineering, Cornell University. Principal Investigators: Dr. John B. Greenly and Dr. Charles E. Seyler. This report summarizes progress during the final year of this project to study the physics of high energy density (HED) plasma streams of 10^17-10^20/cm3 density and high velocity (~100-500 km/s). Such streams are produced from 5-250 micrometer diameter wires heated and ionized by a 1 MA, 250 ns current pulse on the COBRA pulsed power facility at Cornell University. Plasma is ablated from the wires and is driven away to high velocity by unbalanced JxB force. A wire, or an array of wires, can persist as an essentially stationary, continuous source of this streaming plasma for >200 ns, even with driving magnetic fields of many Tesla and peak current densities in the plasma of many MA/cm2. At the heart of the ablation stream generation is the continuous transport of mass from the relatively cold, near-solid-density wire "core" into current-carrying plasma within 1 mm of the wire, followed by the magnetic acceleration of that plasma and its trapped flux to form a directed stream. In the first two years of this program, an advancing understanding of ablation physics led to the discovery of several novel wire ablation experimental regimes. In the final year, one of these new HED plasma regimes has been studied in quantitative detail. This regime studies highly reproducible magnetic reconnection in strongly radiating plasma with supersonic and superalfvenic flow, and shock structures in the outflow. The key discovery is that very heavy wires, e.g. 250 micrometer diameter Al or 150 micrometer Cu, behave in a qualitatively different way than the lighter wires typically used in wire-array Z-pinches. Such wires can be configured to produce a static magnetic X-point null geometry that stores magnetic and thermal energy; reconnection and outflow are triggered when the current begins to decrease and the electric field reverses. The reconnecting flow is driven by both magnetic and thermal pressure forces, and it has been found to be possible to vary the configuration so that one or the other dominates. The magnetic null extends into a current sheet that is heated and radiates strongly, with supersonic outflows. This is the first study of reconnection in this HED plasma regime. This compressible, radiative regime, and the triggering mechanism, may be relevant to solar and astrophysical processes. The PERSEUS extended MHD code has been developed for simulation of these phenomena, and will continue to be used and further developed to help interpret and understand experimental results, as well as to guide experimental design. The code is well-suited to simulations of shocks, and includes Hall and electron inertia physics that appear to be of importance in a number of ablation flow regimes, and definitely in the reconnection regime when gradient scales are comparable to the ion inertial scale. During the final year, our graduate student supported by this grant completed a new version of PERSEUS with the finite volume computational scheme replaced by a discontinuous Galerkin method that gives much less diffusive behavior and allows faster run time and higher spatial resolution. Thecode is now being used to study shock structures produced in the outflow region of the reconnection regime.

  11. Ripples Ruffle Primordial Plasma | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Ripples Ruffle Primordial Plasma Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) Community Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: Email Us More Information » 11.01.15 Ripples Ruffle Primordial Plasma RHIC physicists discover key evidence for a

  12. High-Density Plasma Arc Heating Studies of FePt Thin Films

    SciTech Connect (OSTI)

    Cole, Amanda C; Thompson, Gregory; Harrell, J. W.; Weston, James; Ott, Ronald D

    2006-01-01

    The effect of pulsed-thermal-processing with high-density plasma arc heating is discussed for 20 nm thick nanocrystalline FePt thin films. The dependence of the A1 {yields} L1{sub 0} phase transformation on pulsed time and radiant energy of the pulse is quantified through x-ray diffraction and alternating gradient magnetometry. For 100 ms and 250 ms pulse widths, the phase transformation was observed. Higher radiant energy densities resulted in a larger measured coercivity associated with the L1{sub 0} phase.

  13. Electron density and temperature measurement by continuum radiation emitted from weakly ionized atmospheric pressure plasmas

    SciTech Connect (OSTI)

    Park, Sanghoo; Choe, Wonho, E-mail: wchoe@kaist.ac.kr [Department of Physics, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Youn Moon, Se [High-enthalpy Plasma Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 561-756 (Korea, Republic of); Park, Jaeyoung [5771 La Jolla Corona Drive, La Jolla, CA 92037 (United States)

    2014-02-24

    The electron-atom neutral bremsstrahlung continuum radiation emitted from weakly ionized plasmas is investigated for electron density and temperature diagnostics. The continuum spectrum in 450–1000?nm emitted from the argon atmospheric pressure plasma is found to be in excellent agreement with the neutral bremsstrahlung formula with the electron-atom momentum transfer cross-section given by Popovi?. In 280–450?nm, however, a large discrepancy between the measured and the neutral bremsstrahlung emissivities is observed. We find that without accounting for the radiative H{sub 2} dissociation continuum, the temperature, and density measurements would be largely wrong, so that it should be taken into account for accurate measurement.

  14. The response of plasma density to breaking inertial gravity wave in the lower regions of ionosphere

    SciTech Connect (OSTI)

    Tang, Wenbo Mahalov, Alex

    2014-04-15

    We present a three-dimensional numerical study for the E and lower F region ionosphere coupled with the neutral atmosphere dynamics. This model is developed based on a previous ionospheric model that examines the transport patterns of plasma density given a prescribed neutral atmospheric flow. Inclusion of neutral dynamics in the model allows us to examine the charge-neutral interactions over the full evolution cycle of an inertial gravity wave when the background flow spins up from rest, saturates and eventually breaks. Using Lagrangian analyses, we show the mixing patterns of the ionospheric responses and the formation of ionospheric layers. The corresponding plasma density in this flow develops complex wave structures and small-scale patches during the gravity wave breaking event.

  15. Current initiation in low-density foam z-pinch plasmas

    SciTech Connect (OSTI)

    Derzon, M.; Nash, T.; Allshouse, G. [and others

    1996-07-01

    Low density agar and aerogel foams were tested as z-pinch loads on the SATURN accelerator. In these first experiments, we studied the initial plasma conditions by measuring the visible emission at early times with a framing camera and 1-D imaging. At later time, near the stagnation when the plasma is hotter, x-ray imaging and spectral diagnostics were used to characterize the plasma. Filamentation and arcing at the current contacts was observed. None of the implosions were uniform along the z-axis. The prime causes of these problems are believed to be the electrode contacts and the current return configuration and these are solvable. Periodic phenomena consistent with the formation of instabilities were observed on one shot, not on others, implying that there may be a way of controlling instabilities in the pinch. Many of the issues involving current initiation may be solvable. Solutions are discussed.

  16. A new method for determining the plasma electron density using three-color interferometer

    SciTech Connect (OSTI)

    Arakawa, Hiroyuki; Kawano, Yasunori; Itami, Kiyoshi

    2012-06-15

    A new method for determining the plasma electron density using the fractional fringes on three-color interferometer is proposed. Integrated phase shift on each interferometer is derived without using the temporal history of the fractional fringes. The dependence on the fringe resolution and the electrical noise are simulated on the wavelengths of CO{sub 2} laser. Short-time integrations of the fractional fringes enhance the reliability of this method.

  17. MIT's Plasma Science Fusion Center: I-Mode Powers Up on Alcator C-Mod

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tokamak | Princeton Plasma Physics Lab I-Mode Powers Up on Alcator C-Mod Tokamak American Fusion News Category: Massachusetts Institute of Technology (MIT) Link: MIT's Plasma Science Fusion Center: I-Mode Powers Up on Alcator C-Mod Tokamak

  18. Science on Saturday: Plastic Electronics | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    6, 2016 - 09:30 Science on Saturday: Plastic Electronics MBG Auditorium @ PPPL Speaker: Professor Lynn Loo...

  19. Exploring Plasma Science Advances from Fusion Findings to Astrophysica...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    physics The meeting focused considerable attention on boundary physics and plasma-material wall interactions, an area of growing emphasis at PPPL. Dennis Whyte, a professor of...

  20. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    5th Annual Meeting of the APS Division of Plasma Physics, Denver, CO - 2013 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data Systems...

  1. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    6th Annual Meeting of the APS Division of Plasma Physics, new orleans, la - 2014 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data...

  2. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4th Annual Meeting of the APS Division of Plasma Physics, Providence, RI - 2012 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data...

  3. MIT Plasma Science & Fusion Center: research>alcator>publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technology & Engineering Useful Links Presentations from the 46th Annual Meeting of the APS Division of Plasma Physics, Savannah, 2004 Invited Orals P. Bonoli Full-wave...

  4. Worldwide conference on plasma science coming to Princeton area...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on topics ranging from basic research to uses for plasma in microchip etching, nano- material manufacturing and other technologies. "This conference occupies a unique niche,"...

  5. Fast magnetic reconnection in low-density electron-positron plasmas

    SciTech Connect (OSTI)

    Bessho, Naoki; Bhattacharjee, A.

    2010-10-15

    Two-dimensional particle-in-cell simulations have been performed to study magnetic reconnection in low-density electron-positron plasmas without a guide magnetic field. Impulsive reconnection rates become of the order of unity when the background density is much smaller than 10% of the density in the initial current layer. It is demonstrated that the outflow speed is less than the upstream Alfven speed, and that the time derivative of the density must be taken into account in the definition of the reconnection rate. The reconnection electric fields in the low-density regime become much larger than the ones in the high-density regime, and it is possible to accelerate the particles to high energies more efficiently. The inertial term in the generalized Ohm's law is the most dominant term that supports a large reconnection electric field. An effective collisionless resistivity is produced and tracks the extension of the diffusion region in the late stage of the reconnection dynamics, and significant broadening of the diffusion region is observed. Because of the broadening of the diffusion region, no secondary islands, which have been considered to play a role to limit the diffusion region, are generated during the extension of the diffusion region in the outflow direction.

  6. Capillary plasma jet: A low volume plasma source for life science applications

    SciTech Connect (OSTI)

    Topala, I. E-mail: tmnagat@ipc.shizuoka.ac.jp; Nagatsu, M. E-mail: tmnagat@ipc.shizuoka.ac.jp

    2015-02-02

    In this letter, we present results from multispectroscopic analysis of protein films, after exposure to a peculiar plasma source, i.e., the capillary plasma jet. This plasma source is able to generate very small pulsed plasma volumes, in kilohertz range, with characteristic dimensions smaller than 1?mm. This leads to specific microscale generation and transport of all plasma species. Plasma diagnosis was realized using general electrical and optical methods. Depending on power level and exposure duration, this miniature plasma jet can induce controllable modifications to soft matter targets. Detailed discussions on protein film oxidation and chemical etching are supported by results from absorption, X-ray photoelectron spectroscopy, and microscopy techniques. Further exploitation of principles presented here may consolidate research interests involving plasmas in biotechnologies and plasma medicine, especially in patterning technologies, modified biomolecule arrays, and local chemical functionalization.

  7. Low Temperature Plasma Science: Not Only the Fourth State of Matter but All of Them. Report of the Department of Energy Office of Fusion Energy Sciences Workshop on Low Temperature Plasmas, March 25-57, 2008

    SciTech Connect (OSTI)

    2008-09-01

    Low temperature plasma science (LTPS) is a field on the verge of an intellectual revolution. Partially ionized plasmas (often referred to as gas discharges) are used for an enormous range of practical applications, from light sources and lasers to surgery and making computer chips, among many others. The commercial and technical value of low temperature plasmas (LTPs) is well established. Modern society would simply be less advanced in the absence of LTPs. Much of this benefit has resulted from empirical development. As the technology becomes more complex and addresses new fields, such as energy and biotechnology, empiricism rapidly becomes inadequate to advance the state of the art. The focus of this report is that which is less well understood about LTPs - namely, that LTPS is a field rich in intellectually exciting scientific challenges and that addressing these challenges will result in even greater societal benefit by placing the development of plasma technologies on a solid science foundation. LTPs are unique environments in many ways. Their nonequilibrium and chemically active behavior deviate strongly from fully ionized plasmas, such as those found in magnetically confined fusion or high energy density plasmas. LTPs are strongly affected by the presence of neutral species-chemistry adds enormous complexity to the plasma environment. A weakly to partially ionized gas is often characterized by strong nonequilibrium in the velocity and energy distributions of its neutral and charged constituents. In nonequilibrium LTP, electrons are generally hot (many to tens of electron volts), whereas ions and neutrals are cool to warm (room temperature to a few tenths of an electron volt). Ions and neutrals in thermal LTP can approach or exceed an electron volt in temperature. At the same time, ions may be accelerated across thin sheath boundary layers to impact surfaces, with impact energies ranging up to thousands of electron volts. These moderately energetic electrons can efficiently create reactive radical fragments and vibrationally and electronically excited species from collisions with neutral molecules. These chemically active species can produce unique structures in the gas phase and on surfaces, structures that cannot be produced in other ways, at least not in an economically meaningful way. Photons generated by electron impact excited species in the plasma can interact more or less strongly with other species in the plasma or with the plasma boundaries, or they can escape from the plasma. The presence of boundaries around the plasma creates strong gradients where plasma properties change dramatically. It is in these boundary regions where externally generated electromagnetic radiation interacts most strongly with the plasma, often producing unique responses. And it is at bounding surfaces where complex plasma-surface interactions occur. The intellectual challenges associated with LTPS center on several themes, and these are discussed in the chapters that follow this overview. These themes are plasma-surface interactions; kinetic, nonlinear properties of LTP; plasmas in multiphase media; scaling laws for LTP; and crosscutting themes: diagnostics, modeling, and fundamental data.

  8. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research Program Information Publications & News Meetings & Seminars Contact Information Physics Research High-Energy- Density Physics Waves & Beams Technology & Engineering...

  9. SCIENCE ON SATURDAY- "Outer Space!" | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    SCIENCE ON SATURDAY- "Outer Space" Joshua E. G. Peek, Hubble Fellow Department of Astronomy, Columbia University Presentation: Office presentation icon SOS19JAN2013JPeekouter...

  10. New Jersey Regional Science Bowl | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    elimination contest with question and answer rounds in the fields of chemistry, biology, physics, astronomy, mathematics and general and earth sciences. Teams from middle, high...

  11. Test particle simulation of direct laser acceleration in a density-modulated plasma waveguide

    SciTech Connect (OSTI)

    Lin, M.-W.; Jovanovic, I.

    2012-11-15

    Direct laser acceleration (DLA) of electrons by the use of the intense axial electric field of an ultrafast radially polarized laser pulse is a promising technique for future compact accelerators. Density-modulated plasma waveguides can be implemented for guiding the propagation of the laser pulse to extend the acceleration distance and for the quasi-phase-matching between the accelerated electrons and the laser pulse. A test particle model is developed to study the optimal axial density modulation structure of plasma waveguides for laser pulses to efficiently accelerate co-propagating electrons. A simple analytical approach is also presented, which can be used to estimate the energy gain in DLA. The analytical model is validated by the test particle simulation. The effect of injection phase and acceleration of electrons injected at various radial positions are studied. The results indicate that a positively chirped density modulation of the waveguide structure is required to accelerate electron with low initial energies, and can be effectively optimized. A wider tolerance on the injection phase and radial distance from the waveguide axis exists for electrons injected with a higher initial energy.

  12. A comparison of parametric decay of oblique Langmuir wave in high and low density magneto-plasmas

    SciTech Connect (OSTI)

    Shahid, M.; Hussain, A.; Department of Physics, Government College University, Lahore-54000 ; Murtaza, G.

    2013-09-15

    The parametric decay instability of an obliquely propagating Langmuir wave into the low-frequency electromagnetic shear Alfven wave and the Left-Handed Circularly Polarized wave has been investigated in an electron-ion plasma, immersed in a uniform external magnetic field. Quantum magneto-hydrodynamic model has been used to find the linear and non-linear response of a high density quantum magneto-plasma. Going to the classical limit (??0) retrieves the results for low density classical plasma. Nonlinear dispersion relations and growth rates are derived with analytically and numerically. It is observed that growth rate in the high density degenerate magneto-plasma increases exponentially, while in the low density classical case it increases logarithmically.

  13. MIT Plasma Science & Fusion left: research>alctor>meetings scheduled

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Garching, Germany 19-21 Oct. 19 June 17 July 18 Dec registration ends: 18 Sept 57th APS Div of Plasma Physics Meeting Savannah, GA 16-20 Nov. May 2015 July May June 30 Nov...

  14. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3rd Annual Meeting of the APS Division of Plasma Physics, Salt Lake City, 2011 Invited Orals C. Fiore Production of Internal Transport Barriers via Self-Generated Mean Flows in...

  15. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2nd Annual Meeting of the APS Division of Plasma Physics, Chicago, 2010 Invited Orals A. Hubbard I-mode regime with an edge energy transport barrier but no particle barrier in...

  16. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8th Annual Meeting of the APS Division of Plasma Physics, Philadelphia, 2006 Invited Orals A. Hubbard H-mode pedestal and threshold studies over an expanded operating space on...

  17. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    7th Annual Meeting of the APS Division of Plasma Physics, Denver, 2005 Invited Orals R. Granetz Gas Jet Disruption Mitigation Studies on AlcatorC-MOD J. Hughes Advances in...

  18. MIT Plasma Science & Fusion Center: research, alcator, publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0th Annual Meeting of the APS Division of Plasma Physics, Dallas, 2008 Invited Orals E. Edlund Observation of Reversed Shear Alfvn Eigenmodes During the Sawtooth Cycle in Alcator...

  19. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  20. Analysis by oxygen atom number density measurement of high-speed hydrophilic treatment of polyimide using atmospheric pressure microwave plasma

    SciTech Connect (OSTI)

    Ono, S.

    2015-03-30

    This paper describes the fundamental experimental data of the plasma surface modification of the polyimide using atmospheric pressure microwave plasma source. The experimental results were discussed from the point of view of the radical’s behavior, which significantly affects the modification mechanism. The purpose of the study is to examine how the value of the oxygen atom density will affect the hydrophilic treatment in the upstream region of the plasma where gas temperature is very high. The surface modification experiments were performed by setting the polyimide film sample in the downstream region of the plasma. The degree of the modification was measured by a water contact angle measurement. The water contact angle decreased less than 30 degrees within 1 second treatment time in the upstream region. Very high speed modification was observed. The reason of this high speed modification seems that the high density radical which contributes the surface modification exist in the upstream region of the plasma. This tendency is supposed to the measured relatively high electron density (~10{sup 15}cm{sup ?3}) at the center of the plasma. We used the electric heating catalytic probe method for oxygen radical measurement. An absolute value of oxygen radical density was determined by catalytic probe measurement and the results show that ~10{sup 15}cm{sup ?3} of the oxygen radical density in the upstream region and decreases toward downstream region. The experimental results of the relation of the oxygen radical density and hydrophilic modification of polyimide was discussed.

  1. MIT Plasma Science & Fusion Center: research>alcator>publications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & News Meetings & Seminars Contact Information Physics Research High-Energy- Density Physics Waves & Beams Technology & Engineering Useful Links APS Presentations New Orleans...

  2. MIT Plasma Science & Fusion Center: research>alcator>introduction

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Contact Information Physics Research High-Energy- Density Physics Waves & Beams Fusion Technology & Engineering Francis Bitter Magnet Laboratoroy Useful Links The links...

  3. NJ Regional Middle School Science Bowl | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    competition in Washington, D.C. The Science Bowl is a double elimination contest with oral question and answer rounds in the fields of chemistry, biology, physics, astronomy and...

  4. Science on Saturday starts Jan. 11 | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science on Saturday starts Jan. 11 By Jeanne Jackson DeVoe January 10, 2014 Tweet Widget Google Plus One Share on Facebook Joshua E. G. Peek, a Hubble Fellow at Columbia...

  5. 2012 USA Science & Engineering Festival | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    USA Science & Engineering Festival View larger image IMG 0658 View larger image IMG 0659 View larger image IMG 0664 View larger image IMG 0667 View larger image IMG 0682 View...

  6. Transition from order to chaos, and density limit, in magnetized plasmas

    SciTech Connect (OSTI)

    Carati, A.; Maiocchi, A.; Marino, M.; Galgani, L.; Zuin, M.; Martines, E.

    2012-09-15

    It is known that a plasma in a magnetic field, conceived microscopically as a system of point charges, can exist in a magnetized state, and thus remain confined, inasmuch as it is in an ordered state of motion, with the charged particles performing gyrational motions transverse to the field. Here, we give an estimate of a threshold, beyond which transverse motions become chaotic, the electrons being unable to perform even one gyration, so that a breakdown should occur, with complete loss of confinement. The estimate is obtained by the methods of perturbation theory, taking as perturbing force acting on each electron that due to the so-called microfield, i.e., the electric field produced by all the other charges. We first obtain a general relation for the threshold, which involves the fluctuations of the microfield. Then, taking for such fluctuations, the formula given by Iglesias, Lebowitz, and MacGowan for the model of a one component plasma with neutralizing background, we obtain a definite formula for the threshold, which corresponds to a density limit increasing as the square of the imposed magnetic field. Such a theoretical density limit is found to fit pretty well the empirical data for collapses of fusion machines.

  7. Understanding the dramatic role of anomalous dispersion on the measurement of electron densities in plasmas using interferometers

    SciTech Connect (OSTI)

    Nilsen, J; Johnson, W R; Iglesias, C A; Scofield, J H

    2005-07-20

    For decades the electron density of plasmas has been measured using optical interferometers. With the availability of good X-ray laser sources in the last decade interferometers have been extended into the wavelength range 14-47 nm, which has enabled researchers to probe even higher density plasmas. The data analysis assumes the index of refraction is due only to the free electrons, which makes the index less than one. Recent interferometer experiments in Al plasmas observed plasmas with index of refraction greater than one at 14 nm and brought into question the validity of the usual formula for calculating the index. In this paper we show how the anomalous dispersion from bound electrons can dominate the free electron contribution to the index of refraction in many plasmas and make the index greater than one or enhance the contribution to the index such that one would greatly overestimate the density of the plasma using interferometers. Using a new average-atom code we calculate the index of refraction in many plasmas at different temperatures for photon energies from 0 to 100 eV and compare against calculations done with OPAL. We also present examples of other plasmas that may have index of refraction greater than one at X-ray laser energies. During the next decade X-ray free electron lasers and other X-ray sources will be available to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

  8. Science on Saturday: Taking the Universe's Baby Picture | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab March 12, 2016, 9:30am Science On Saturday MBG Auditorium at PPPL Science on Saturday: Taking the Universe's Baby Picture Professor David Spergel Princeton University Abstract: PDF icon D. Spergel.pdf LIVE STREAMING LINK: https://mediacentral.princeton.edu/id/1_wdp1m3et Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov Host(s): Dr. Andrew Zwicker azwicker@pppl.gov PPPL Entrance Procedures Visitor Information, Directions, Security at PPPL As a federal

  9. Science on Saturday: Music and 3D Audio | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    February 13, 2016, 9:30am Science On Saturday MBG Auditorium, PPPL Science on Saturday: Music and 3D Audio Professor Edgar Choueiri Princeton University Abstract: PDF icon 06 Choueiri.pdf Science_on_Saturday13Feb2016_EChoueiri Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov Host(s): Dr. Andrew Zwicker azwicker@pppl.gov PPPL Entrance Procedures Visitor Information, Directions, Security at PPPL As a federal facility, the Princeton Plasma Physics Laboratory is operating

  10. Viscosity and dilepton production of a chemically equilibrating quark-gluon plasma at finite baryon density

    SciTech Connect (OSTI)

    Guan Nana; Li Jianwei; He Zejun; Long Jiali; Cai Xiangzhou; Ma Yugang; Shen Wenqing

    2009-07-15

    By considering the effect of shear viscosity we have investigated the evolution of a chemically equilibrating quark-gluon plasma at finite baryon density. Based on the evolution of the system we have performed a complete calculation for the dilepton production from the following processes: qq{yields}ll, qq{yields}gll, Compton-like scattering (qg{yields}qll,qg{yields}qll), gluon fusion (gg{yields}cc), annihilation (qq{yields}cc), as well as the multiple scattering of quarks. We have found that quark-antiquark annihilation, Compton-like scatterring, gluon fusion, and multiple scattering of quarks give important contributions. Moreover, we have also found that the dilepton yield is an increasing function of the initial quark chemical potential, and the increase of the quark phase lifetime because of the viscosity also obviously raises the dilepton yield.

  11. Magnetic reconnection in high-energy-density laser-produced plasmas

    SciTech Connect (OSTI)

    Fox, W.; Bhattacharjee, A.; Germaschewski, K.

    2012-05-15

    Recently, novel experiments on magnetic reconnection have been conducted in laser-produced plasmas in a high-energy-density regime. Individual plasma bubbles self-generate toroidal, mega-gauss-scale magnetic fields through the Biermann battery effect. When multiple bubbles are created at small separation, they expand into one another, driving reconnection of this field. Reconnection in the experiments was reported to be much faster than allowed by both Sweet-Parker, and even Hall-MHD theories, when normalized to the nominal magnetic fields self-generated by single bubbles. Through particle-in-cell simulations (both with and without a binary collision operator), we model the bubble interaction at parameters and geometry relevant to the experiments. This paper discusses in detail the reconnection regime of the laser-driven experiments and reports the qualitative features of simulations. We find substantial flux-pileup effects, which boost the relevant magnetic field for reconnection in the current sheet. When this is accounted for, the normalized reconnection rates are much more in line with standard two-fluid theory of reconnection. At the largest system sizes, we additionally find that the current sheet is prone to breakup into plasmoids.

  12. 2013 Pathways to Science Summit | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pathways to Science Summit View larger image IMG 2061 View larger image IMG 2063 View larger image IMG 2062 View larger image IMG 2067 View larger image IMG 2068 View larger image IMG 2069 View larger image IMG 2070 View larger image IMG 2073 View larger image IMG 2081 View larger image IMG 2085 View larger image IMG 2096 View larger image IMG 2101 View larger image IMG 2103 View larger image IMG 2104 View larger image IMG 2105 View larger image IMG 2106 View larger image IMG 2107

  13. COLLOQUIUM: The Promise of Urban Science | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    April 16, 2013, 3:15pm to 4:30pm Colloquia MBG Auditorium COLLOQUIUM: The Promise of Urban Science Professor Steven E. Koonin New York University Presentation: File TC16APR2013_SEKooninWO31_34.pptx For the first time in history, more than half of the world's population lives in urban areas; by mid-century, 70 percent of the world's more than 9 billion people will live in cities. Enabling those cities to deliver services effectively, efficiently, and sustainably while keeping citizens safe,

  14. Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma

    SciTech Connect (OSTI)

    Gupta, Deepak K.; Deng, B. H.; Knapp, K.; Sun, X.; Thompson, M. C.

    2012-10-15

    In C-2 field-reversed configuration (FRC) device, low neutral density outside the FRC separatrix is required to minimize the charge exchange loss of fast particles. Titanium gettering is used in C-2 to reduce the wall recycling and keep the neutral density low in plasma edge. The measurements of neutral density radial profile are desirable to understand the plasma recycling and the effects of titanium gettering. These measurements are also needed to study the interaction of neutral beams with FRC plasma and confinement of fast ions. Diagnostic based on absolute deuterium Balmer-alpha (D-alpha) radiation measurements is developed and deployed on C-2 device to measure the radial profile of neutral density. Simultaneous measurements of electron density and temperature are done using CO{sub 2} interferometer, Thomson scattering, and triple probes diagnostics along with absolute D-alpha radiation. Abel inversion was performed to get the time dependent radial profile of the local D-alpha emission density. Neutral density profiles are obtained under different machine conditions of titanium deposition.

  15. Measurement of a density profile of a hot-electron plasma in RT-1 with three-chord interferometry

    SciTech Connect (OSTI)

    Saitoh, H.; Yano, Y.; Yoshida, Z.; Nishiura, M.; Morikawa, J.; Kawazura, Y.; Nogami, T.; Yamasaki, M.

    2015-02-15

    The electron density profile of a plasma in a magnetospheric dipole field configuration was measured with a multi-chord interferometry including a relativistic correction. In order to improve the accuracy of density reconstruction, a 75?GHz interferometer was installed at a vertical chord of the Ring Trap 1 (RT-1) device in addition to previously installed ones at tangential and another vertical chords. The density profile was calculated by using the data of three-chord interferometry including relativistic effects for a plasma consisting of hot and cold electrons generated by electron cyclotron resonance heating (ECH). The results clearly showed the effects of density peaking and magnetic mirror trapping in a strongly inhomogeneous dipole magnetic field.

  16. Whistler wave radiation from a pulsed loop antenna located in a cylindrical duct with enhanced plasma density

    SciTech Connect (OSTI)

    Kudrin, Alexander V.; Shkokova, Natalya M.; Ferencz, Orsolya E.; Zaboronkova, Tatyana M.

    2014-11-15

    Pulsed radiation from a loop antenna located in a cylindrical duct with enhanced plasma density is studied. The radiated energy and its distribution over the spatial and frequency spectra of the excited waves are derived and analyzed as functions of the antenna and duct parameters. Numerical results referring to the case where the frequency spectrum of the antenna current is concentrated in the whistler range are reported. It is shown that under ionospheric conditions, the presence of an artificial duct with enhanced density can lead to a significant increase in the energy radiated from a pulsed loop antenna compared with the case where the same source is immersed in the surrounding uniform magnetoplasma. The results obtained can be useful in planning active ionospheric experiments with pulsed electromagnetic sources operated in the presence of artificial field-aligned plasma density irregularities that are capable of guiding whistler waves.

  17. Argon–germane in situ plasma clean for reduced temperature Ge on Si epitaxy by high density plasma chemical vapor deposition

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Douglas, Erica A.; Sheng, Josephine J.; Verley, Jason C.; Carroll, Malcolm S.

    2015-06-04

    We found that the demand for integration of near infrared optoelectronic functionality with silicon complementary metal oxide semiconductor (CMOS) technology has for many years motivated the investigation of low temperature germanium on silicon deposition processes. Our work describes the development of a high density plasma chemical vapor deposition process that uses a low temperature (<460 °C) in situ germane/argon plasma surface preparation step for epitaxial growth of germanium on silicon. It is shown that the germane/argon plasma treatment sufficiently removes SiOx and carbon at the surface to enable germanium epitaxy. Finally, the use of this surface preparation step demonstrates anmore » alternative way to produce germanium epitaxy at reduced temperatures, a key enabler for increased flexibility of integration with CMOS back-end-of-line fabrication.« less

  18. Argon–germane in situ plasma clean for reduced temperature Ge on Si epitaxy by high density plasma chemical vapor deposition

    SciTech Connect (OSTI)

    Douglas, Erica A.; Sheng, Josephine J.; Verley, Jason C.; Carroll, Malcolm S.

    2015-06-04

    We found that the demand for integration of near infrared optoelectronic functionality with silicon complementary metal oxide semiconductor (CMOS) technology has for many years motivated the investigation of low temperature germanium on silicon deposition processes. Our work describes the development of a high density plasma chemical vapor deposition process that uses a low temperature (<460 °C) in situ germane/argon plasma surface preparation step for epitaxial growth of germanium on silicon. It is shown that the germane/argon plasma treatment sufficiently removes SiOx and carbon at the surface to enable germanium epitaxy. Finally, the use of this surface preparation step demonstrates an alternative way to produce germanium epitaxy at reduced temperatures, a key enabler for increased flexibility of integration with CMOS back-end-of-line fabrication.

  19. Wall current probe: A non-invasive in situ plasma diagnostic for space and time resolved current density distribution measurement

    SciTech Connect (OSTI)

    Baude, R.; Gaboriau, F.; Hagelaar, G. J. M. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse Cedex 9, France and CNRS, LAPLACE, F-31062, Toulouse (France)] [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse Cedex 9, France and CNRS, LAPLACE, F-31062, Toulouse (France)

    2013-08-15

    In the context of low temperature plasma research, we propose a wall current probe to determine the local charged particle fluxes flowing to the chamber walls. This non-intrusive planar probe consists of an array of electrode elements which can be individually biased and for which the current can be measured separately. We detail the probe properties and present the ability of the diagnostic to be used as a space and time resolved measurement of the ion and electron current density at the chamber walls. This diagnostic will be relevant to study the electron transport in magnetized low-pressure plasmas.

  20. Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Office of Science Office of Science * * * Office of Science Office of * * * * * Office of Science Office of Science * * * Office of Science * * * * 287 115...

  1. Density and x-ray emission profile relationships in highly ionized high-Z laser-produced plasmas

    SciTech Connect (OSTI)

    Yoshida, Kensuke; Fujioka, Shinsuke Ugomori, Teruyuki; Tanaka, Nozomi; Azechi, Hiroshi; Nishimura, Hiroaki; Higashiguchi, Takeshi Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryoichi; Ejima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Sunahara, Atsushi; Li, Bowen; Dunne, Padraig; O'Sullivan, Gerry; Yanagida, Tatsuya

    2015-03-23

    We present a benchmark measurement of the electron density profile in the region where the electron density is 10{sup 19?}cm{sup –3} and where the bulk of extreme ultraviolet (EUV) emission occurs from isotropically expanding spherical high-Z gadolinium plasmas. It was found that, due to opacity effects, the observed EUV emission is mostly produced from an underdense region. We have analyzed time-resolved emission spectra with the aid of atomic structure calculations and find the multiple ion charge states around 18+ during the laser pulse irradiation.

  2. Increasing the upper-limit intensity and temperature range for thermal self-focusing of a laser beam by using plasma density ramp-up

    SciTech Connect (OSTI)

    Bokaei, B.; Niknam, A. R.

    2014-03-15

    This work is devoted to improving relativistic and ponderomotive thermal self-focusing of the intense laser beam in an underdense plasma. It is shown that the ponderomotive nonlinearity induces a saturation mechanism for thermal self-focusing. Therefore, in addition to the well-known lower-limit critical intensity, there is an upper-limit intensity for thermal self-focusing above which the laser beam starts to experience ponderomotive defocusing. It is indicated that the upper-limit intensity value is dependent on plasma and laser parameters such as the plasma electron temperature, plasma density, and laser spot size. Furthermore, the effect of the upward plasma density ramp profile on the thermal self-focusing is studied. Results show that by using the plasma density ramp-up, the upper-limit intensity increases and the self-focusing temperature range expands.

  3. One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma

    SciTech Connect (OSTI)

    Chaplin, Vernon H.; Bellan, Paul M.

    2015-12-28

    A time-dependent two-fluid model has been developed to understand axial variations in the plasma parameters in a very high density (peak ne~ > 5x1019 m–3) argon inductively coupled discharge in a long 1.1 cm radius tube. The model equations are written in 1D, with radial losses to the tube walls accounted for by the inclusion of effective particle and energy sink terms. The ambipolar diffusion equation and electron energy equation are solved to find the electron density ne(z,t) and temperature Te(z,t), and the populations of the neutral argon 4s metastable, 4s resonant, and 4p excited state manifolds are calculated in order to determine the stepwise ionization rate and calculate radiative energy losses. The model has been validated through comparisons with Langmuir probe ion saturation current measurements; close agreement between the simulated and measured axial plasma density profiles and the initial density rise rate at each location was obtained at pAr = 30-60 mTorr. Lastly, we present detailed results from calculations at 60 mTorr, including the time-dependent electron temperature, excited state populations, and energy budget within and downstream of the radiofrequency (RF) antenna.

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

    SciTech Connect (OSTI)

    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 providing access to researchers around the world. The paper will conclude with a discussion of LIFE, its development path and potential to enable a carbon-free clean energy future.

  5. Generating end plug potentials in tandem mirror plasma confinement by heating thermal particles so as to escape low density end stoppering plasmas

    DOE Patents [OSTI]

    Baldwin, D.E.; Logan, B.G.

    The invention provides a method and apparatus for raising the potential of a magnetic mirror cell by pumping charged particles of the opposite sign of the potential desired out of the mirror cell through excitation, with the pumping being done by an externally imposed field at the bounce frequence of the above charged particles. These pumped simple mirror cells then provide end stoppering for a center mirror cell for the tandem mirror plasma confinement apparatus. For the substantially complete pumping case, the end plugs of a tandem mirror can be up to two orders of magnitude lower in density for confining a given center mirror cell plasma than in the case of end plugs without pumping. As a result the decrease in recirculating power required to keep the system going, the technical state of the art required, and the capital cost are all greatly lowered.

  6. Generating end plug potentials in tandem mirror plasma confinement by heating thermal particles so as to escape low density end stoppering plasmas

    DOE Patents [OSTI]

    Baldwin, David E.; Logan, B. Grant

    1981-01-01

    The invention provides a method and apparatus for raising the potential of a magnetic mirror cell by pumping charged particles of the opposite sign of the potential desired out of the mirror cell through excitation, with the pumping being done by an externally imposed field at the bounce frequency of the above charged particles. These pumped simple mirror cells then provide end stoppering for a center mirror cell for the tandem mirror plasma confinement apparatus. For the substantially complete pumping case, the end plugs of a tandem mirror can be up to two orders of magnitude lower in density for confining a given center mirror cell plasma than in the case of end plugs without pumping. As a result the decrease in recirculating power required to keep the system going, the technological state of the art required, and the capital cost are all greatly lowered.

  7. Inductively Driven, 3D Liner Compression of a Magnetized Plasma to Megabar Energy Densities

    SciTech Connect (OSTI)

    Slough, John

    2015-02-01

    To take advantage of the smaller scale, higher density regime of fusion an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. What is proposed is a more flexible metallic liner compression scheme that minimizes the kinetic energy required to reach fusion. It is believed that it is possible to accomplish this at sub-megajoule energies. This however will require operation at very small scale. To have a realistic hope of inexpensive, repetitive operation, it is essential to have the liner kinetic energy under a megajoule which allows for the survivability of the vacuum and power systems. At small scale the implosion speed must be reasonably fast to maintain the magnetized plasma (FRC) equilibrium during compression. For limited liner kinetic energy, it becomes clear that the thinnest liner imploded to the smallest radius consistent with the requirements for FRC equilibrium lifetime is desired. The proposed work is directed toward accomplishing this goal. Typically an axial (Z) current is employed for liner compression. There are however several advantages to using a θ-pinch coil. With the θ-pinch the liner currents are inductively driven which greatly simplifies the apparatus and vacuum system, and avoids difficulties with the post implosion vacuum integrity. With fractional flux leakage, the foil liner automatically provides for the seed axial compression field. To achieve it with optimal switching techniques, and at an accelerated pace however will require additional funding. This extra expense is well justified as the compression technique that will be enabled by this funding is unique in the ability to implode individual segments of the liner at different times. This is highly advantageous as the liner can be imploded in a manner that maximizes the energy transfer to the FRC. Production of shaped liner implosions for additional axial compression can thus be readily accomplished with the modified power modules. The additional energy and switching capability proposed will thus provide for optimal utilization of the liner energy. The following tasks were outlined for the three year effort: (1) Design and assemble the foil liner compression test structure and chamber including the compression bank and test foils [Year 1]. (2) Perform foil liner compression experiments and obtain performance data over a range on liner dimensions and bank parameters [Year 2]. (3) Carry out compression experiments of the FRC plasma to Megagauss fields and measure key fusion parameters [Year 3]. (4) Develop numerical codes and analyze experimental results, and determine the physics and scaling for future work [Year 1-3]. The principle task of the project was to design and assemble the foil liner FRC formation chamber, the full compression test structure and chamber including the compression bank. This task was completed successfully. The second task was to test foils in the test facility constructed in year one and characterize the performance obtained from liner compression. These experimental measurements were then compared with analytical predictions, and numerical code results. The liner testing was completed and compared with both the analytical results as well as the code work performed with the 3D structural dynamics package of ANSYS Metaphysics®. This code is capable of modeling the dynamic behavior of materials well into the non-linear regime (e.g. a bullet hit plate glass). The liner dynamic behavior was found to be remarkably close to that predicted by the 3D structural dynamics results. Incorporating a code that can also include the magnetics and plasma physics has also made significant progress at the UW. The remaining test bed construction and assembly task is was completed, and the FRC formation and merging experiments were carried out as planned. The liner compression of the FRC to Megagauss fields was not performed due to not obtaining a sufficiently long lived FRC during the final year of the grant. Modifications planned to correct this deficiency included a larger FRC source as well as a much larger liner driver energy storage system. Due to discontinuation of the grant neither of these improvements were carried out.

  8. Multi-dimensional collective effects in high-current relativistic beams relevant to High Density Laboratory Plasmas

    SciTech Connect (OSTI)

    Shvets, Gennady

    2014-05-09

    In summary, an analytical model describing the self-pinching of a relativistic charge-neutralized electron beam undergoing the collisionless Weibel instability in an overdense plasma has been developed. The model accurately predicts the final temperature and size of the self-focused filament. It is found that the final temperature is primarily defined by the total beam’s current, while the filament’s radius is shown to be smaller than the collisionless skin depth in the plasma and primarily determined by the beam’s initial size. The model also accurately predicts the repartitioning ratio of the initial energy of the beam’s forward motion into the magnetic field energy and the kinetic energy of the surrounding plasma. The density profile of the final filament is shown to be a superposition of the standard Bennett pinch profile and a wide halo surrounding the pinch, which contains a significant fraction of the beam’s electrons. PIC simulations confirm the key assumption of the analytic theory: the collisionless merger of multiple current filaments in the course of the Weibel Instability provides the mechanism for Maxwellization of the beam’s distribution function. Deviations from the Maxwell-Boltzmann distribution are explained by incomplete thermalization of the deeply trapped and halo electrons. It is conjectured that the simple expression derived here can be used for understanding collsionless shock acceleration and magnetic field amplification in astrophysical plasmas.

  9. Impact of the pedestal plasma density on dynamics of edge localized mode crashes and energy loss scaling

    SciTech Connect (OSTI)

    Xu, X. Q.; Ma, J. F.; Li, G. Q.

    2014-12-15

    The latest BOUT++ studies show an emerging understanding of dynamics of edge localized mode (ELM) crashes and the consistent collisionality scaling of ELM energy losses with the world multi-tokamak database. A series of BOUT++ simulations are conducted to investigate the scaling characteristics of the ELM energy losses vs collisionality via a density scan. Linear results demonstrate that as the pedestal collisionality decreases, the growth rate of the peeling-ballooning modes decreases for high n but increases for low n (1?plasma and yields an increasing ELM size with decreasing collisionality after a series of micro-bursts. The pedestal plasma density plays a major role in determining the ELM energy loss through its effect on the edge bootstrap current and ion diamagnetic stabilization. The critical trend emerges as a transition (1) linearly from ballooning-dominated states at high collisionality to peeling-dominated states at low collisionality with decreasing density and (2) nonlinearly from turbulence spreading dynamics at high collisionality into avalanche-like dynamics at low collisionality.

  10. Access to a New Plasma Edge State with High Density and Pressures using Quiescent H-mode

    SciTech Connect (OSTI)

    Solomon, Wayne M.; Snyder, P. B.; Burrell, K. H.; Fenstermacher, M. E.; Garofalo, A. M.; Grierson, B. A.; Loarte, A.; McKee, G. R.; Nazikian, R; Osborne, T. H.

    2014-07-01

    A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over standard edge localized mode (ELM)ing H-mode at these parameters. The thermal energy confinement time increases both as a result of the increased pedestal height and improvements in the core transport and reduced low-k turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.

  11. Radiation from Ag high energy density Z-pinch plasmas and applications to lasing

    SciTech Connect (OSTI)

    Weller, M. E. Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Shrestha, I.; Stafford, A.; Keim, S. F.; Shlyaptseva, V. V.; Osborne, G. C.; Petkov, E. E.; Apruzese, J. P.; Giuliani, J. L.; Chuvatin, A. S.

    2014-03-15

    Silver (Ag) wire arrays were recently introduced as efficient x-ray radiators and have been shown to create L-shell plasmas that have the highest electron temperature (>1.8?keV) observed on the Zebra generator so far and upwards of 30?kJ of energy output. In this paper, results of single planar wire arrays and double planar wire arrays of Ag and mixed Ag and Al that were tested on the UNR Zebra generator are presented and compared. To further understand how L-shell Ag plasma evolves in time, a time-gated x-ray spectrometer was designed and fielded, which has a spectral range of approximately 3.5–5.0?Ĺ. With this, L-shell Ag as well as cold L{sub ?} and L{sub ?} Ag lines was captured and analyzed along with photoconducting diode (PCD) signals (>0.8?keV). Along with PCD signals, other signals, such as filtered XRD (>0.2?keV) and Si-diodes (SiD) (>9?keV), are analyzed covering a broad range of energies from a few eV to greater than 53?keV. The observation and analysis of cold L{sub ?} and L{sub ?} lines show possible correlations with electron beams and SiD signals. Recently, an interesting issue regarding these Ag plasmas is whether lasing occurs in the Ne-like soft x-ray range, and if so, at what gains? To help answer this question, a non-local thermodynamic equilibrium (LTE) kinetic model was utilized to calculate theoretical lasing gains. It is shown that the Ag L-shell plasma conditions produced on the Zebra generator at 1.7 maximum current may be adequate to produce gains as high as 6?cm{sup ?1} for various 3p???3s transitions. Other potential lasing transitions, including higher Rydberg states, are also included in detail. The overall importance of Ag wire arrays and plasmas is discussed.

  12. Electron density measurements of atmospheric-pressure non-thermal N{sub 2} plasma jet by Stark broadening and irradiance intensity methods

    SciTech Connect (OSTI)

    Xiao, Dezhi; Shen, Jie; Lan, Yan; Xie, Hongbing; Shu, Xingsheng; Meng, Yuedong; Li, Jiangang; Cheng, Cheng E-mail: paul.chu@cityu.edu.hk; Chu, Paul K. E-mail: paul.chu@cityu.edu.hk

    2014-05-15

    An atmospheric-pressure non-thermal plasma jet excited by high frequency alternating current using nitrogen is developed and the electron density in the active region of this plasma jet is investigated by two different methods using optical emission spectroscopy, Stark broadening, and irradiance intensity method. The irradiance intensity method shows that the average electron density is about 10{sup 20}/m{sup 3} which is slightly smaller than that by the Stark broadening method. However, the trend of the change in the electron density with input power obtained by these two methods is consistent.

  13. A high-resolution imaging x-ray crystal spectrometer for high energy density plasmas

    SciTech Connect (OSTI)

    Chen, Hui E-mail: bitter@pppl.gov; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P.; Bitter, M. E-mail: bitter@pppl.gov; Hill, K. W.; Kerr, S.

    2014-11-15

    Adapting a concept developed for magnetic confinement fusion experiments, an imaging crystal spectrometer has been designed and tested for HED plasmas. The instrument uses a spherically bent quartz [211] crystal with radius of curvature of 490.8 mm. The instrument was tested at the Titan laser at Lawrence Livermore National Laboratory by irradiating titanium slabs with laser intensities of 10{sup 19}–10{sup 20} W/cm{sup 2}. He-like and Li-like Ti lines were recorded, from which the spectrometer performance was evaluated. This spectrometer provides very high spectral resolving power (E/dE > 7000) while acquiring a one-dimensional image of the source.

  14. Scattering of Radio Frequency Waves by Edge Density Blobs in Tokamak Plasmas

    SciTech Connect (OSTI)

    Ram, A. K.; Hizanidis, K.; Kominis, Y.

    2011-12-23

    The density blobs and fluctuations present in the edge region of magnetic fusion devices can scatter radio frequency (RF) waves through refraction and diffraction. The scattering can diffuse the rays in space and in wave-vector space. The diffusion in space can make the rays miss their intended target region, while the diffusion in wave-vector space can broaden the wave spectrum and modify the wave damping and current profile.

  15. THERMAL ANNEALING OF ZNO FILMS USING HIGH-DENSITY PLASMA ARC LAMPS

    SciTech Connect (OSTI)

    Sabau, Adrian S; Dinwiddie, Ralph Barton; Xu, Jun; Angelini, Joseph Attilio; Harper, David C

    2011-01-01

    Nanostructured materials are rarely synthesized with appropriate phase and/or morphology. In this study, critical additional of as-synthesized nanostructured materials, such as annealing and/or activation of dopants, are addressed using infrared plasma arc lamps (PAL) over areas as large as 1,000 cm2. The broad spectral range of the PAL and the spectral variation of light absorption in nanostructured materials make the selection of processing parameters extremely difficult, posing a major technological barrier. In this study, the measurement of the surface temperature using various techniques for ZnO films on crystalline silicon wafers is discussed. An energy transport model for the simulation of rapid thermal processing using PAL is presented. The experimental and computational results show that the surface temperature cannot be measured directly and that computer simulation results are an effective tool for obtaining accurate data on processing temperatures.

  16. A Radiative Transport Model for Heating Paints using High Density Plasma Arc Lamps

    SciTech Connect (OSTI)

    Sabau, Adrian S; Duty, Chad E; Dinwiddie, Ralph Barton; Nichols, Mark; Blue, Craig A; Ott, Ronald D

    2009-01-01

    The energy distribution and ensuing temperature evolution within paint-like systems under the influence of infrared radiation was studied. Thermal radiation effects as well as those due to heat conduction were considered. A complete set of material properties was derived and discussed. Infrared measurements were conducted to obtain experimental data for the temperature in the paint film. The heat flux of the incident radiation from the plasma arc lamp was measured using a heat flux sensor with a very short response time. The comparison between the computed and experimental results for temperature show that the models that are based on spectral four-flux RTE and accurate optical properties yield accurate results for the black paint systems.

  17. Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Stockpile Stewardship National Security National Competitiveness Fusion and Ignition Energy for the Future How to Make a Star Discovery Science Photon Science HAPLS

  18. DIRECT RADIO PROBING AND INTERPRETATION OF THE SUN'S PLASMA DENSITY PROFILE

    SciTech Connect (OSTI)

    Cairns, I. H.; Lobzin, V. V.; Li, B.; Robinson, P. A.; Warmuth, A.; Mann, G.

    2009-12-01

    The Sun's electron number density profile n{sub e} (r) is vital for solar physics but not well measured or understood within a few solar radii R{sub S} . Here, a new technique extracts n{sub e} (r) directly from coronal type III radio bursts for 40 <= f <= 180 MHz. Unexpectedly, wind-like regions with n{sub e} propor to (r - R{sub S} ){sup -2} are quite common below 2R{sub S} , and coronal type IIIs often have closely linear 1/f - t spectra. The profile n{sub e} propor to (r - R{sub S} ){sup -2} is consistent with the radio data and simulations and is interpreted in terms of conical flow from localized sources (e.g., UV funnels) close to the photosphere. It is consistent with solar wind acceleration occurring for 2 <= r/R{sub S} <= 10.

  19. Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... Because the higher harmonics effects are not important in our case, a hot plasma ... We study plasma heating at ci but not at the harmonics of this frequency, so that ...

  20. DOE Science Showcase - DOE Plasma Research | OSTI, US Dept of Energy,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Office of Scientific and Technical Information DOE Plasma Research Image credit: NASA Plasma, the electrified gas that surrounds and illuminates our world, is the fourth state of matter. The behavior, nature, and complexity of plasma allows DOE scientists, research institutions and international partners to research a diverse number of applications that are significant to our world. DOE plasma theorists are developing the fundamental plasma theory and computational base needed to understand

  1. Measurement of Electron Density near Plasma Grid of Large-scaled Negative Ion Source by Means of Millimeter-Wave Interferometer

    SciTech Connect (OSTI)

    Nagaoka, K.; Tokuzawa, T.; Tsumori, K.; Nakano, H.; Ito, Y.; Osakabe, M.; Ikeda, K.; Kisaki, M.; Shibuya, M.; Sato, M.; Komada, S.; Kondo, T.; Hayashi, H.; Asano, E.; Takeiri, Y.; Kaneko, O.

    2011-09-26

    A millimeter-wave interferometer with the frequency of 39 GHz ({lambda} 7.7 mm) was newly installed to a large-scaled negative ion source. The measurable line-integrated electron density (n{sub e}l) is from 2x10{sup 16} to 7x10{sup 18} m{sup -2}, where n{sub e} and l represent an electron density and the plasma length along the millimeter-wave path, respectively. Our interest in this study is behavior of negative ions and reduction of electron density in the beam extraction region near the plasma grid. The first results show the possibility of the electron density measurement by the millimeter-wave interferometer in this region. The line-averaged electron density increases proportional to the arc power under the condition without cesium seeding. The significant decrease of the electron density and significant increase of the negative ion density were observed just after the cesium seeding. The electron density measured with the interferometer agrees well with that observed with a Langmuir probe. The very high negative ion ratio of n{sub H-}/(n{sub e}+n{sub H-}) = 0.85 was achieved within 400 min. after the cesium seeding.

  2. Scaling of Microcavity Plasmas Toward 1 µm: Science and Engineering of Spatially-Confined, Low Temperature Plasmas

    SciTech Connect (OSTI)

    Eden, J G

    2012-03-07

    The DOE has provided, by means of the American Recovery and Reinvestment Act (ARRA), $146,400 in funding for the purchase of scientific equipment. Specifically, these funds have enabled the purchase of two scientific cameras that have already been applied to the research in microcavity plasmas at the University of Illinois (Urbana). The first camera system that was purchased with these funds is a gated ICCD system that allows events as short as 5 ns in time to be captured. It is difficult to express the impact that this equipment has already had on our research. Despite having arrived just 6 - 7 months ago, this camera system has already been used by five graduate students and several undergraduates to capture phenomena that we simply could not see in the past. As an example, the low temperature plasma confined to a spiral structure we fabricate in the Al/Al?O? materials system appears, on long time scales such as those we see with our eyes, to be spatially uniform. However, when captured with the new camera system, the plasma actually is formed initially at the center of the spiral and then moves radially (literally, "jumping" over channels as it goes) at a velocity of a few km/sec. This is an exciting result and I should add that the camera shows that plasma standing waves are produced in some of the structures as well. We do not currently understand all of the phenomena we are witnessing but it is obvious that this new system has quite literally opened new areas of plasma research and application. The second system purchased under this ARRA grant is an infrared system that is far more sensitive than anything our laboratory (or the University of Illinois, for that matter) has had previously. Although fewer experiments have been completed to date with this second camera, it is already clear that it is, indeed, extremely sensitive and it is slated for several experiments in the near future in which we will be measuring the infrared spectra of several arrays of microcavity plasmas. In summary, let me express my thanks to the DOE for granting these funds. We are most grateful for the extraordinary scientific capability that thee funds provide our students. We expect that the scientific data already acquired by this equipment will result in several publications in the next 2 - 3 months (two are being written now). Furthermore, the ability we now have to watch plasmas evolve on the nanosecond time scale has given us several ideas that are likely to result in patent applications. On behalf of our students and myself, I thank the DOE for this exceptional equipment.

  3. Absolute atomic oxygen and nitrogen densities in radio-frequency driven atmospheric pressure cold plasmas: Synchrotron vacuum ultra-violet high-resolution Fourier-transform absorption measurements

    SciTech Connect (OSTI)

    Niemi, K.; O'Connell, D.; Gans, T.; Oliveira, N. de; Joyeux, D.; Nahon, L.; Booth, J. P.

    2013-07-15

    Reactive atomic species play a key role in emerging cold atmospheric pressure plasma applications, in particular, in plasma medicine. Absolute densities of atomic oxygen and atomic nitrogen were measured in a radio-frequency driven non-equilibrium plasma operated at atmospheric pressure using vacuum ultra-violet (VUV) absorption spectroscopy. The experiment was conducted on the DESIRS synchrotron beamline using a unique VUV Fourier-transform spectrometer. Measurements were carried out in plasmas operated in helium with air-like N{sub 2}/O{sub 2} (4:1) admixtures. A maximum in the O-atom concentration of (9.1 {+-} 0.7) Multiplication-Sign 10{sup 20} m{sup -3} was found at admixtures of 0.35 vol. %, while the N-atom concentration exhibits a maximum of (5.7 {+-} 0.4) Multiplication-Sign 10{sup 19} m{sup -3} at 0.1 vol. %.

  4. ScienceLive chat page: on the future of fusion research | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab ScienceLive chat page: on the future of fusion research American Fusion News Category: U.S. Universities Link: ScienceLive chat page: on the future of fusion research

  5. Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC

    ScienceCinema (OSTI)

    Andrei Seryi

    2010-01-08

    Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators.  FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.  

  6. U.S. Department of Energy's Plasma Science Center holds third...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    graduate student, discussed his poster on dusty plasmas with PPPL physicist Erik Gilson. (Photo by Elle Starkman, PPPL Office of Communications) Jeff Walker, a University of...

  7. Diagnostics - Plasma Couette Experiment - Cary Forest Group - UW Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Diagnostics UW Madison Plasma Couette Experiment Diagnostics PCX HomeResearch MissionPhysics TopicsDeviceDiagnosticsContacts LinksPCX People CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation Diagnostics A combination Langmuir/Mach probe is radially scanned approximately 2.5" above the bottom endcap set of magnet & electrode rings. Electron temperature and plasma density is measured using a

  8. Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    confinement by circularly polarized electromagnetic field in toroidal geometry Vladimir A. Svidzinski University of Wisconsin-Madison, Madison, Wisconsin 53706, USA and Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA Í‘Received 21 May 2007; accepted 2 July 2007; published online 31 October 2007Í’ A novel plasma confinement concept based on plasma confinement by electromagnetic pressure of circularly polarized electromagnetic fields is proposed. Practical implementation of this

  9. Al{sub 2}O{sub 3} multi-density layer structure as a moisture permeation barrier deposited by radio frequency remote plasma atomic layer deposition

    SciTech Connect (OSTI)

    Jung, Hyunsoo [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Samsung Display Co. Ltd., Tangjeong, Chungcheongnam-Do 336-741 (Korea, Republic of); Jeon, Heeyoung [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Choi, Hagyoung; Ham, Giyul; Shin, Seokyoon [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jeon, Hyeongtag, E-mail: hjeon@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2014-02-21

    Al{sub 2}O{sub 3} films deposited by remote plasma atomic layer deposition have been used for thin film encapsulation of organic light emitting diode. In this study, a multi-density layer structure consisting of two Al{sub 2}O{sub 3} layers with different densities are deposited with different deposition conditions of O{sub 2} plasma reactant time. This structure improves moisture permeation barrier characteristics, as confirmed by a water vapor transmission rate (WVTR) test. The lowest WVTR of the multi-density layer structure was 4.7 × 10{sup ?5} gm{sup ?2} day{sup ?1}, which is one order of magnitude less than WVTR for the reference single-density Al{sub 2}O{sub 3} layer. This improvement is attributed to the location mismatch of paths for atmospheric gases, such as O{sub 2} and H{sub 2}O, in the film due to different densities in the layers. This mechanism is analyzed by high resolution transmission electron microscopy, elastic recoil detection, and angle resolved X-ray photoelectron spectroscopy. These results confirmed that the multi-density layer structure exhibits very good characteristics as an encapsulation layer via location mismatch of paths for H{sub 2}O and O{sub 2} between the two layers.

  10. Departures from local thermodynamic equilibrium in cutting arc plasmas derived from electron and gas density measurements using a two-wavelength quantitative Schlieren technique

    SciTech Connect (OSTI)

    Prevosto, L.; Mancinelli, B.; Artana, G.; Kelly, H.

    2011-03-15

    A two-wavelength quantitative Schlieren technique that allows inferring the electron and gas densities of axisymmetric arc plasmas without imposing any assumption regarding statistical equilibrium models is reported. This technique was applied to the study of local thermodynamic equilibrium (LTE) departures within the core of a 30 A high-energy density cutting arc. In order to derive the electron and heavy particle temperatures from the inferred density profiles, a generalized two-temperature Saha equation together with the plasma equation of state and the quasineutrality condition were employed. Factors such as arc fluctuations that influence the accuracy of the measurements and the validity of the assumptions used to derive the plasma species temperature were considered. Significant deviations from chemical equilibrium as well as kinetic equilibrium were found at elevated electron temperatures and gas densities toward the arc core edge. An electron temperature profile nearly constant through the arc core with a value of about 14000-15000 K, well decoupled from the heavy particle temperature of about 1500 K at the arc core edge, was inferred.

  11. The Ronald E. Hatcher SCIENCE ON SATURDAY Lecture Series | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab The Ronald E. Hatcher SCIENCE ON SATURDAY Lecture Series In memory of our beloved Science on Saturday host, Ronald E. Hatcher. The 2016 Ronald E. Hatcher Science on Saturday Lecture Series is scheduled to run from January 9th through March 12th. Download a copy of our flyer here! Science on Saturday is a series of lectures given by scientists, engineers, and other professionals involved in cutting-edge research. Held on Saturday mornings throughout winter, the lectures are geared

  12. Physical Sciences 2007 Science & Technology Highlights

    SciTech Connect (OSTI)

    Hazi, A U

    2008-04-07

    The Physical Sciences Directorate applies frontier physics and technology to grand challenges in national security. Our highly integrated and multidisciplinary research program involves collaborations throughout Lawrence Livermore National Laboratory, the National Nuclear Security Administration, the Department of Energy, and with academic and industrial partners. The Directorate has a budget of approximately $150 million, and a staff of approximately 350 employees. Our scientists provide expertise in condensed matter and high-pressure physics, plasma physics, high-energy-density science, fusion energy science and technology, nuclear and particle physics, accelerator physics, radiation detection, optical science, biotechnology, and astrophysics. This document highlights the outstanding research and development activities in the Physical Sciences Directorate that made news in 2007. It also summarizes the awards and recognition received by members of the Directorate in 2007.

  13. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2014-05-15

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

  14. Off Site University Research (OSUR) | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    universities in various areas of plasma and fusion science. These areas include: plasma theory and simulation; plasma experiments; plasma diagnostics; undergraduate plasma...

  15. Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and researchers at work. News Releases Science Briefs Photos Picture of the Week Social Media Videos Fact Sheets Publications PHOTOS BY TOPIC Careers Community Visitors...

  16. science

    National Nuclear Security Administration (NNSA)

    through the Predictive Capability Framework (PCF). The PCF is a long-term integrated roadmap to guide the science, technology and engineering activities and Directed Stockpile...

  17. Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    U.S. Department of energy atmospheric radiation measurement program ARM ARM The ... of Science created the Atmospheric Radiation Measurement (ARM) Program within the ...

  18. NNSA 2014 Stewardship Science Academic Programs Annual

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0 2014 Stewardship Science Academic Programs Annual â—Ź Stewardship Science Academic Alliances â—Ź High Energy Density Laboratory Plasmas â—Ź National Laser Users' Facility â—Ź Predictive Science Academic Alliance Program On the Cover Direct numerical simulation of a hydrogen jet injected from a wall into a turbulent boundary layer. Isosurfaces of vorticity magnitude are colored by the local streamwise velocity. The lower-right inset shows a top-down view of the simulation while the upper-left

  19. Space and time resolved spectroscopy of laser-produced plasmas: A study of density-sensitive x-ray transitions in helium-like and neon-like ions

    SciTech Connect (OSTI)

    Young, Bruce Kai Fong

    1988-09-01

    The determination of level populations and detailed population mechanisms in dense plasmas has become an increasingly important problem in atomic physics. In this work, the density variation of line intensities and level populations in aluminum K-shell and molybdenum and silver L-shell emission spectra have been measured from high-powered, laser-produced plasmas. For each case, the density dependence of the observed line emission is due to the effect of high frequency electron-ion collisions on metastable levels. The density dependent line intensities vary greatly in laser-produced plasmas and can be used to extract detailed information concerning the population kinetics and level populations of the ions. The laser-plasmas had to be fully characterized in order to clearly compare the observed density dependence with atomic theory predictions. This has been achieved through the combined use of new diagnostic instruments and microdot targets which provided simultaneously space, time, and spectrally resolved data. The plasma temperatures were determined from the slope of the hydrogen-like recombination continuum. The time resolved electron density profiles were measured using multiple frame holographic interferometry. Thus, the density dependence of K-shell spectral lines could be clearly examined, independent of assumptions concerning the dynamics of the plasma. In aluminum, the electron density dependence of various helium-like line intensity ratios were measured. Standard collisional radiative equilibrium models fail to account for the observed density dependence measured for the ''He/sub ..cap alpha..//IC'' ratio. Instead, a quasi-steady state atomic model based on a purely recombining plasma is shown to accurately predict the measured density dependence. This same recombining plasma calculation successfully models the density dependence of the high-n ''He/sub ..gamma..//He/sub ..beta../'' and ''He/sub delta//He/sub ..beta../'' helium-like resonance line intensity ratios.

  20. Microsoft Word - Defense Science Quarterly 03-09.doc

    National Nuclear Security Administration (NNSA)

    March 2009 Defense Science Quarterly Inside This Issue 1 Message from the Director 2 Carnegie-DOE Alliance Center 3 Cornell Center for the Study of Pulsed Power Driven High Energy Density Plasmas 4 Center of Excellence for Radioactive Ion Beam Studies for Stewardship Science 5 The Texas Center for High Intensity Laser Science 6 The Institute for Shock Physics, Washington State University 7 The High Pressure Science and Engineering Center at the University of Nevada, Las Vegas 8 HEDP Research at

  1. Generation of very low energy-spread electron beams using low-intensity laser pulses in a low-density plasma

    SciTech Connect (OSTI)

    Upadhyay, Ajay K.; Samant, Sushil Arun; Sarkar, Deepangkar; Krishnagopal, Srinivas; Jha, Pallavi

    2011-03-15

    The possibility of obtaining high-energy electron beams of high quality by using a low-density homogeneous plasma and a low-intensity laser (just above the self-injection threshold in the bubble regime) has been explored. Three-dimensional simulations are used to demonstrate, for the first time, an energy-spread of less than 1%, from self-trapping. More specifically, for a plasma density of 2x10{sup 18} cm{sup -3} and a laser intensity of a{sub 0}=2, a high-energy (0.55 GeV), ultrashort (1.4 fs) electron beam with very low energy-spread (0.55%) and high current (3 kA) is obtained. These parameters satisfy the requirements for drivers of short-wavelength free-electron lasers. It is also found that the quality of the electron beam depends strongly on the plasma length, which therefore needs to be optimized carefully to get the best performance in the experiments.

  2. Time and space resolved measurement of the electron temperature, mass density and ionization state in the ablation plasma between two exploding Al wires

    SciTech Connect (OSTI)

    Knapp, P. F.; Pikuz, S. A.; Shelkovenko, T. A.; Hammer, D. A.; Hansen, S. B.

    2012-05-15

    We have determined the properties of plasma around and between two exploding wires using high-resolution x-ray absorption spectroscopy. Plasma densities and temperatures ranging from Greater-Than-Or-Equivalent-To 0.1g/cm{sup 3} and a few eV to less than 0.01 g/cm{sup 3} and 30 eV have been measured in experiments at Cornell University with two 40 {mu}m aluminum (Al) wires spaced 1 mm apart driven by {approx}150 kA peak current pulses with 100 ns rise time. The wire plasma was backlit by the 1.4-1.6 keV continuum radiation produced by a Mo wire X-pinch. The spectrometer employed two spherically bent quartz crystals to record the absorption and backlighter spectra simultaneously. The transition between the dense Al wire core and the coronal plasma is seen as a transition from cold K-edge absorption to Mg-, Na-, and finally Ne-like absorption at the boundary. In the plasma that accumulates between the wires, ionization states up to C-Like Al are observed. The spectrometer geometry and {approx}2{mu}m X-pinch source size provide 0.3 eV spectral resolution and 20 {mu}m spatial resolution enabling us to see 1s{yields} 2p satellite transitions as separate lines as well as O-, F-, and Ne-like 1s{yields} 3p transitions that have not been seen before. A step wedge was used to calibrate the transmission, enabling density to be measured within a factor of two and temperature to be measured within {+-}25%. A genetic algorithm was developed to fit synthetic spectra calculated using the collisional-radiative code SCRAM to the experimental spectra. In order to obtain agreement it was necessary to assume multiple plasma regions with variable thicknesses, thereby allowing the inferred plasma conditions to vary along the absorption path.

  3. Fusion through the eyes of a veteran science journalist | Princeton Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Lab Fusion through the eyes of a veteran science journalist July 15, 2013 Tweet Widget Google Plus One Share on Facebook Daniel Clery (Photo by Sadie Windscheffel-Clarke) Daniel Clery Gallery: Author Daniel Clery recently published "A Piece of the Sun," a 320-page narrative of the history of fusion research and the personalities who have devoted their careers to it. Clery is a United Kingdom-based reporter for Science magazine who holds a bachelor's degree in theoretical

  4. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  5. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  6. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  7. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  8. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  9. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  10. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  11. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  12. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2015 Report Cards FY 2014 Report Cards FY 2013 Report Cards Report Card Archives Laboratory Planning Process Laboratory Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202)

  13. Moiré deflectometry using the Talbot-Lau interferometer as refraction diagnostic for High Energy Density plasmas at energies below 10 keV

    SciTech Connect (OSTI)

    Valdivia, M. P.; Stutman, D.; Finkenthal, M.

    2014-07-15

    The highly localized density gradients expected in High Energy Density (HED) plasma experiments can be characterized by x-ray phase-contrast imaging in addition to conventional attenuation radiography. Moiré deflectometry using the Talbot-Lau grating interferometer setup is an attractive HED diagnostic due to its high sensitivity to refraction induced phase shifts. We report on the adaptation of such a system for operation in the sub-10 keV range by using a combination of free standing and ultrathin Talbot gratings. This new x-ray energy explored matches well the current x-ray backlighters used for HED experiments, while also enhancing phase effects at lower electron densities. We studied the performance of the high magnification, low energy Talbot-Lau interferometer, for single image phase retrieval using Moiré fringe deflectometry. Our laboratory and simulation studies indicate that such a device is able to retrieve object electron densities from phase shift measurements. Using laboratory x-ray sources from 7 to 15 ?m size we obtained accurate simultaneous measurements of refraction and attenuation for both sharp and mild electron density gradients.

  14. Estimation of the electron density and radiative energy losses in a calcium plasma source based on an electron cyclotron resonance discharge

    SciTech Connect (OSTI)

    Potanin, E. P. Ustinov, A. L.

    2013-06-15

    The parameters of a calcium plasma source based on an electron cyclotron resonance (ECR) discharge were calculated. The analysis was performed as applied to an ion cyclotron resonance system designed for separation of calcium isotopes. The plasma electrons in the source were heated by gyrotron microwave radiation in the zone of the inhomogeneous magnetic field. It was assumed that, in such a combined trap, the energy of the extraordinary microwave propagating from the high-field side was initially transferred to a small group of resonance electrons. As a result, two electron components with different transverse temperatures-the hot resonance component and the cold nonresonance component-were created in the plasma. The longitudinal temperatures of both components were assumed to be equal. The entire discharge space was divided into a narrow ECR zone, where resonance electrons acquired transverse energy, and the region of the discharge itself, where the gas was ionized. The transverse energy of resonance electrons was calculated by solving the equations for electron motion in an inhomogeneous magnetic field. Using the law of energy conservation and the balance condition for the number of hot electrons entering the discharge zone and cooled due to ionization and elastic collisions, the density of hot electrons was estimated and the dependence of the longitudinal temperature T{sub e Parallel-To} of the main (cold) electron component on the energy fraction {beta} lost for radiation was obtained.

  15. Confinement analyses of the high-density field-reversed configuration plasma in the field-reversed configuration experiment with a liner

    SciTech Connect (OSTI)

    Zhang Shouyin; Intrator, T.P.; Wurden, G.A.; Waganaar, W.J.; Taccetti, J.M.; Renneke, R.; Grabowski, C.; Ruden, E.L.

    2005-05-15

    The focus of the field-reversed configuration (FRC) experiment with a liner (FRX-L) is the formation of a target FRC plasma for magnetized target fusion experiments. An FRC plasma with density of 10{sup 23} m{sup -3}, total temperature in the range of 150-300 eV, and a lifetime of {approx_equal}20 {mu}s is desired. Field-reversed {theta}-pinch technology is used with programed cusp fields at {theta}-coil ends to achieve non-tearing field line reconnections during FRC formation. Well-formed FRCs with density between (2-4)x10{sup 22} m{sup -3}, lifetime in the range of 15-20 {mu}s, and total temperature between 300-500 eV are reproducibly created. Key FRC parameters have standard deviation in the mean of 10% during consecutive shots. The FRCs are formed at 50 mTorr deuterium static fill using 2 kG net reversed bias field inside the {theta}-coil confinement region, with external main field unexpectedly ranging between 15-30 kG. The high-density FRCs confinement properties are approximately in agreement with empirical scaling laws obtained from previous experiments with fill pressure mostly less than 20 mTorr. Analyses in this paper reveal that reducing the external main field modulation and/or extending the {theta}-coil length in the FRX-L device are critical in achieving higher FRC parameters for application in magnetized target fusion.

  16. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Physics Almost all of the observable matter in the universe is in the plasma state. Formed at high temperatures, plasmas consist of freely moving ions and free electrons. They are often called the "fourth state of matter" because their unique physical properties distinguish them from solids, liquids and gases. Plasma densities and temperatures vary widely, from the cold gases of interstellar space to the extraordinarily hot, dense cores of stars and inside a detonating nuclear

  17. Time dependent Doppler shifts in high-order harmonic generation in intense laser interactions with solid density plasma and frequency chirped pulses

    SciTech Connect (OSTI)

    Welch, E. C.; Zhang, P.; He, Z.-H.; Dollar, F.; Krushelnick, K.; Thomas, A. G. R.

    2015-05-15

    High order harmonic generation from solid targets is a compelling route to generating intense attosecond or even zeptosecond pulses. However, the effects of ion motion on the generation of harmonics have only recently started to be considered. Here, we study the effects of ion motion in harmonics production at ultrahigh laser intensities interacting with solid density plasma. Using particle-in-cell simulations, we find that there is an optimum density for harmonic production that depends on laser intensity, which scales linearly with a{sub 0} with no ion motion but with a reduced scaling if ion motion is included. We derive a scaling for this optimum density with ion motion and also find that the background ion motion induces Doppler red-shifts in the harmonic structures of the reflected pulse. The temporal structure of the Doppler shifts is correlated to the envelope of the incident laser pulse. We demonstrate that by introducing a frequency chirp in the incident pulse we are able to eliminate these Doppler shifts almost completely.

  18. Absolute CF{sub 2} density and gas temperature measurements by absorption spectroscopy in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Xu, Yong Peng, Fei; Gong, Fa-Ping; Li, Xiao-Song; Zhu, Ai-Min; Liu, Yong-Xin; Wang, You-Nian

    2014-10-15

    Broadband ultraviolet absorption spectroscopy has been used to determine the CF{sub 2} radical density in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas, using the CF{sub 2} A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system of absorption spectrum. The rotational temperature of ground state CF{sub 2} and excited state CF was also estimated by using A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system and B{sup 2}??X{sup 2}? system, respectively. The translational gas temperature was deduced from the Doppler width of the Ar{sup *}({sup 3}P{sub 2}) and Ar{sup *}({sup 3}P{sub 0}) metastable atoms absorption line by using the tunable diode laser absorption spectroscopy. The rotational temperatures of the excited state CF are about 100?K higher than those of ground state CF{sub 2}, and about 200?K higher than the translational gas temperatures. The dependences of the radical CF{sub 2} density, electron density, electron temperature, rotational temperature, and gas temperature on the high frequency power and pressure have been analyzed. Furthermore, the production and loss mechanisms of CF{sub 2} radical and the gas heating mechanisms have also been discussed.

  19. Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Wikipedia to forecast diseases November 13, 2014 Los Alamos research published in Public Library of Science LOS ALAMOS, N.M., Nov. 13, 2014-Scientists can now monitor and forecast diseases around the globe more effectively by analyzing views of Wikipedia articles, according to a team from Los Alamos National Laboratory. "A global disease-forecasting system will improve the way we respond to epidemics," scientist Sara Del Valle said. "In the same way we check the weather each

  20. Applied Mathematics and Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    skills database Electron density simulation Electron density from an orbital-free quantum molecular dynamics simulation for a warm dense plasma of deuterium at density 10 gcc and...

  1. Research | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U...

  2. Stark broadening for diagnostics of the electron density in non-equilibrium plasma utilizing isotope hydrogen alpha lines

    SciTech Connect (OSTI)

    Yang, Lin; Tan, Xiaohua; Wan, Xiang; Chen, Lei; Jin, Dazhi; Qian, Muyang; Li, Gongping

    2014-04-28

    Two Stark broadening parameters including FWHM (full width at half maximum) and FWHA (full width at half area) of isotope hydrogen alpha lines are simultaneously introduced to determine the electron density of a pulsed vacuum arc jet. To estimate the gas temperature, the rotational temperature of the C{sub 2} Swan system is fit to 2500?±?100?K. A modified Boltzmann-plot method with b{sub i}-factor is introduced to determine the modified electron temperature. The comparison between results of atomic and ionic lines indicates the jet is in partial local thermodynamic equilibrium and the electron temperature is close to 13?000?±?400?K. Based on the computational results of Gig-Card calculation, a simple and precise interpolation algorithm for the discrete-points tables can be constructed to obtain the traditional n{sub e}-T{sub e} diagnostic maps of two Stark broadening parameters. The results from FWHA formula by the direct use of FWHM?=?FWHA and these from the diagnostic map are different. It can be attributed to the imprecise FWHA formula form and the deviation between FWHM and FWHA. The variation of the reduced mass pair due to the non-equilibrium effect contributes to the difference of the results derived from two hydrogen isotope alpha lines. Based on the Stark broadening analysis in this work, a corrected method is set up to determine n{sub e} of (1.10?±?0.08)?×?10{sup 21}?m{sup ?3}, the reference reduced mass ?{sub 0} pair of (3.30?±?0.82 and 1.65?±?0.41), and the ion kinetic temperature of 7900?±?1800?K.

  3. Stewardship Science Academic Alliances Annual

    National Nuclear Security Administration (NNSA)

    2011 Office of Stockpile Stewardship Stewardship Science Academic Alliances High Energy Density Laboratory Plasmas National Laser Users' Facility DOE/NA-0016 This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors or their employees, makes any warranty, express or implied, or assumes any legal liability or

  4. Stewardship Science Academic Alliances Annual

    National Nuclear Security Administration (NNSA)

    2012 DOE/NA-0018 Stewardship Science Academic Alliances National Laser Users' Facility High Energy Density Laboratory Plasmas A color composite (red=H2, green=HI, blue=OIII) of a small portion of Carina shows the spectacular structures that result when radiation from massive stars interacts with molecular globules that harbour newborn stars. Image Courtesy of Patrick Hartigan, Rice University, taken with the 4-m NOAO telescope at Cerro Tololo, Chile On the cover This report was prepared as an

  5. High Energy Density Microwaves

    SciTech Connect (OSTI)

    Phillips, R.M. [Stanford Linear Accelerator Center, Stanford, CA 94309 (United States)

    1999-04-01

    These proceedings represent papers presented at the RF98 Workshop entitled `High Energy Density Microwaves` held in California in October, 1998. The topics discussed were predominantly accelerator{minus}related. The Workshop dealt, for the most part, with the generation and control of electron beams, the amplification of RF signals, the design of mode converters, and the effect of very high RF field gradients. This Workshop was designed to address the concerns of the microwave tube industry worldwide, the plasma physicists who deal with very high beam currents and gigawatts of RF power, and researchers in accelerator centers around the world. Papers were presented on multibeam klystrons, gyrotron development, plasmas in microwave tubes, RF breakdown, and alternatives to conventional linear coliders at 1 TeV and above. The Workshop was partially sponsored by the US Department of Energy. There were 46 papers presented at the conference,out of which 19 have been abstracted for the Energy,Science and Technology database.(AIP)

  6. Fusion Energy Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fusion Energy Sciences Fusion Energy Sciences Expanding the fundamental understanding of matter at very high temperatures and densities and to build the scientific foundation ...

  7. Study of electron acceleration and x-ray radiation as a function of plasma density in capillary-guided laser wakefield accelerators

    SciTech Connect (OSTI)

    Ju, J.; Döpp, A.; Cros, B.; Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlström, C.-G.; Ferrari, H.

    2013-08-15

    Laser wakefield electron acceleration in the blow-out regime and the associated betatron X-ray radiation were investigated experimentally as a function of the plasma density in a configuration where the laser is guided. Dielectric capillary tubes were employed to assist the laser keeping self-focused over a long distance by collecting the laser energy around its central focal spot. With a 40 fs, 16 TW pulsed laser, electron bunches with tens of pC charge were measured to be accelerated to an energy up to 300 MeV, accompanied by X-ray emission with a peak brightness of the order of 10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW. Electron trapping and acceleration were studied using the emitted X-ray beam distribution to map the acceleration process; the number of betatron oscillations performed by the electrons was inferred from the correlation between measured X-ray fluence and beam charge. A study of the stability of electron and X-ray generation suggests that the fluctuation of X-ray emission can be reduced by stabilizing the beam charge. The experimental results are in good agreement with 3D particle-in-cell (PIC) simulation.

  8. Final report for the NSF/DOE partnership in basic plasma science grant DE-FG02-06ER54906 '?Laser-driven collisionless shocks in the Large Plasma Device'?

    SciTech Connect (OSTI)

    Niemann, Christoph; Gekelman, W.; Winske, D.; Larsen, D.

    2012-12-14

    We have performed several thousand high-energy laser shots in the LAPD to investigate the dynamics of an exploding laser-produced plasma in a large ambient magneto-plasma. Debris-ions expanding at super-Alfvenic velocity (up to MA=1.5) expel the ambient magnetic field, creating a large (> 20 cm) diamagnetic cavity. We observed field compressions of up to B/B{sub 0} = 1.5 at the edge of the bubble, consistent with the MHD jump conditions, as well as localized electron heating at the edge of the bubble. Two-dimensional hybrid simulations reproduce these measurements well and show that the majority of the ambient ions are energized by the magnetic piston to super-Alfvenic speeds and swept outside the bubble volume. Nonlinear shear-Alfven waves ({delta}B/B{sub 0} > 25%) are radiated from the cavity with a coupling efficiency of 70% from magnetic energy in the bubble to the wave. While the data is consistent with a weak magneto-sonic shock, the experiments were severely limited by the low ambient plasma densities (10{sup 12} cm{sup -3}). 2D hybrid simulations indicate that future experiments with the new LAPD plasma source and densities in excess of 10{sup 13} cm{sup -3} will drive full-blown collisionless shocks with MA>10 over several c/wpi and shocked Larmor radii. In a separate experiment at the LANL Trident laser facility we have performed a proof-of-principle experiment at higher densities to demonstrate key elements of collisionless shocks in laser-produced magnetized plasmas with important implications to NIF. Simultaneously we have upgraded the UCLA glass-laser system by adding two large amplitude disk amplifiers from the NOVA laser and boost the on-target energy from 30 J to up to 1 kJ, making this one of the world’s largest university-scale laser systems. We now have the infrastructure in place to perform novel and unique high-impact experiments on collision-less shocks at the LAPD.

  9. Frontiers for Discovery in High Energy Density Physics

    SciTech Connect (OSTI)

    Davidson, R. C.; Katsouleas, T.; Arons, J.; Baring, M.; Deeney, C.; Di Mauro, L.; Ditmire, T.; Falcone, R.; Hammer, D.; Hill, W.; Jacak, B.; Joshi, C.; Lamb, F.; Lee, R.; Logan, B. G.; Melissinos, A.; Meyerhofer, D.; Mori, W.; Murnane, M.; Remington, B.; Rosner, R.; Schneider, D.; Silvera, I.; Stone, J.; Wilde, B.; Zajc. W.

    2004-07-20

    The report is intended to identify the compelling research opportunities of high intellectual value in high energy density physics. The opportunities for discovery include the broad scope of this highly interdisciplinary field that spans a wide range of physics areas including plasma physics, laser and particle beam physics, nuclear physics, astrophysics, atomic and molecular physics, materials science and condensed matter physics, intense radiation-matter interaction physics, fluid dynamics, and magnetohydrodynamics

  10. Technical Reports - Disclaimer | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports Technical...

  11. PPPL Technical Reports | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technical Reports - Disclaimer NSTX-U Education Organization Contact Us Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics...

  12. Research | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U Education Organization Contact Us Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U Research The U.S. Department of Energy's Princeton Plasma Physics Laboratory is dedicated to developing fusion as

  13. Experimental investigations of electron density and ion energy distributions in dual-frequency capacitively coupled plasmas for Ar/CF{sub 4} and Ar/O{sub 2}/CF{sub 4} discharges

    SciTech Connect (OSTI)

    Liu, Jia; Liu, Yong-Xin; Gao, Fei; Wang, You-Nian, E-mail: ynwang@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Bi, Zhen-Hua [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China)

    2014-01-07

    The electron density and ion energy distribution (IED) are investigated in low-pressure dual-frequency capacitively coupled Ar/CF{sub 4} (90%/10%) and Ar/O{sub 2}/CF{sub 4} (80%/10%/10%) plasmas. The relations between controllable parameters, such as high-frequency (HF) power, low-frequency (LF) power and gas pressure, and plasma parameters, such as electron density and IEDs, are studied in detail by utilizing a floating hairpin probe and an energy resolved quadrupole mass spectrometer, respectively. In our experiment, the electron density is mainly determined by the HF power and slightly influenced by the LF power. With increasing gas pressure, the electron density first goes up rapidly to a maximum value and then decreases at various HF and LF powers. The HF power also plays a considerable role in affecting the IEDs under certain conditions and the ion energy independently controlled by the LF source is discussed here. For clarity, some numerical results obtained from a two-dimensional fluid model are presented.

  14. DOEFES_Plasma_Frontiers_Townhall_Vay.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    J.-L. Vay, E. Esarey, A. Koniges Lawrence Berkeley National Laboratory J. Barnard, A. Friedman, D. Grote Lawrence Livermore National Laboratory Frontiers of Plasma Science Workshops - Town Hall June 30-July 1, 2015 Predictive Community Computational Tools for Virtual Plasma Science Experiments 2 2 UNIVERSITY OF CALIFORNIA Office of Science Advanced simula.ons play an increasingly important role in plasma science . Plasmas exhibit very complex interrelated mul.-scale mul.-physics phenomena: è

  15. Biological Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Energy Science Engineering Science Environmental Science Fusion Science Math & Computer Science Nuclear Science Share Your Research NERSC Citations Home Science at...

  16. Theoretical Fusion Research | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Theory & Computational Department Weekly Highlights Weekly Seminars Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U Education Organization Contact Us Overview Experimental Fusion Research Theoretical Fusion Research Theory & Computational Department Weekly Highlights Weekly Seminars Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U Theoretical Fusion Research About

  17. Nathaniel J Fisch | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nathaniel J Fisch Director, Program in Plasma Physics Professor Nathaniel Fisch is Associate Director for Academic Affairs at PPPL, and Professor of Astrophysical Sciences and the Director of the Program in Plasma Physics at Princeton University. His professional interests include: plasma physics with applications to nuclear fusion, astrophysics, plasma-based pulse compression, plasma thrusters, plasma processing, laser-based plasma accelerators, and atomic radiation in plasmas; complex liquids

  18. Princeton Plasma Physics Laboratory

    SciTech Connect (OSTI)

    Not Available

    1990-01-01

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  19. Voyager 2 observations of plasmas and flows out to 104 AU

    SciTech Connect (OSTI)

    Richardson, J. D.; Decker, R. B. E-mail: robert.decker@apljhu.edu

    2014-09-10

    Voyager 2 has crossed through 20 AU of the heliosheath; assuming the same heliosheath thickness as at Voyager 1, it is now two-thirds of the way to the heliopause. The plasma data are generally of good quality, although the increasing flow angle of the plasma makes analysis more difficult. The average plasma speed has remained constant but the flow angles have increased to almost 60° in the RT plane and to almost 30° in the RN plane. The average density and thermal speed have been constant since a density increase observed in 2011. Comparison of V2 plasma flows derived from plasma science experiment (PLS) data and Low Energy Charged Particle (LECP) proton anisotropies give good agreement except when heavy ion contributions or non-convective proton anisotropies are observed in the LECP data.

  20. Intense Magnetized Plasma-Wall Interaction

    SciTech Connect (OSTI)

    Bauer, Bruno S.; Fuelling, Stephan

    2013-11-30

    This research project studied wall-plasma interactions relevant to fusion science. Such interactions are a critical aspect of Magneto-Inertial Fusion (MIF) because flux compression by a pusher material, in particular the metal for the liner approach to MIF, involves strong eddy current heating on the surface of the pusher, and probably interactions and mixing of the pusher with the interior fuel during the time when fusion fuel is being burned. When the pusher material is a metal liner, high-energy-density conditions result in fascinating behavior. For example, "warm dense matter" is produced, for which material properties such as resistivity and opacity are not well known. In this project, the transformation into plasma of metal walls subjected to pulsed megagauss magnetic fields was studied with an experiment driven by the UNR 1 MA Zebra generator. The experiment was numerically simulated with using the MHRDR code. This simple, fundamental high-energy-density physics experiment, in a regime appropriate to MIF, has stimulated an important and fascinating comparison of numerical modeling codes and tables with experiment. In addition, we participated in developing the FRCHX experiment to compress a field-reversed-configuration (FRC) plasma with a liner, in collaboration with researchers from Air Force Research Laboratory and Los Alamos National Lab, and we helped develop diagnostics for the Plasma Liner Experiment (PLX) at LANL. Last, but not least, this project served to train students in high-energy-density physics.

  1. Science & Technology - 2015

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    example is the use of betatron x-ray radiation for research in the growing field of high energy density (HED) science on extremely short time and length scales (energy density is...

  2. Laser Plasma Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and controlling laser produced plasmas for fusion and basic science Contact David Montgomery (505) 665-7994 Email John Kline (505) 667-7062 Email Thomson scattering is widely...

  3. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    nuclear astrophysics, material properties, plasma physics, nonlinear optical physics, radiation sources, radiative properties, and other areas of science. NIF will generate...

  4. The evolution of ion charge states in cathodic vacuum arc plasmas: a review

    SciTech Connect (OSTI)

    Anders, Andre

    2011-12-18

    Cathodic vacuum arc plasmas are known to contain multiply charged ions. 20 years after “Pressure Ionization: its role in metal vapour vacuum arc plasmas and ion sources” appeared in vol. 1 of Plasma Sources Science and Technology, it is a great opportunity to re-visit the issue of pressure ionization, a non-ideal plasma effect, and put it in perspective to the many other factors that influence observable charge state distributions, such as the role of the cathode material, the path in the density-temperature phase diagram, the “noise” in vacuum arc plasma as described by a fractal model approach, the effects of external magnetic fields and charge exchange collisions with neutrals. A much more complex image of the vacuum arc plasma emerges putting decades of experimentation and modeling in perspective.

  5. AlGaN UV LED and Photodiodes Radiation Hardness and Space Qualifications and Their Applications in Space Science and High Energy Density Physics

    SciTech Connect (OSTI)

    Sun, K. X.

    2011-05-31

    This presentation provides an overview of robust, radiation hard AlGaN optoelectronic devices and their applications in space exploration & high energy density physics. Particularly, deep UV LED and deep UV photodiodes are discussed with regard to their applications, radiation hardness and space qualification. AC charge management of UV LED satellite payload instruments, which were to be launched in late 2012, is covered.

  6. Graduate Programs | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Graduate Programs PPPL supports graduate education primarily through the Program in Plasma Physics in the Department of Astrophysical Sciences of Princeton University. Students are admitted directly to the Program and are granted degrees through the Department of Astrophysical Sciences. In addition, through the interdepartmental Program in Plasma Science and Technology, PPPL supports students in affiliated engineering and science departments, who pursue research in plasma physics, while

  7. Igor Kaganovich | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Igor Kaganovich Research Physicist, Plasma Physics Laboratory. Dr. Kaganovich is a principal research physicist at Princeton Plasma Physics Laboratory. His professional interests include: beam-plasma interaction, high energy density plasmas, nanotechnology, atomic physics, and physics of partially ionized plasmas. He is involved in research in many areas of plasma physics with applications to nuclear fusion (heavy ion fusion), gas discharge modeling, and plasma processing. Dr. Kaganovich serves

  8. Galleries | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Education About Blog Programs Galleries Upcoming Events Lab Outreach Efforts Graduate Programs Off Site University Research (OSUR) Organization Contact Us Science Education About Blog Programs Galleries Upcoming Events Lab Outreach Efforts Graduate Programs Off Site University Research (OSUR) Galleries Subscribe to RSS - Galleries 2013 Young Women's Conference 2013 Young Women's Conference63 images 2013 Plasma Camp 2013 Plasma Camp7 images 2013 Science on Saturday Lecture Series 2013

  9. Sandia National Laboratories: Research: Materials Science: Image...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    About Materials Science Research Image Gallery Video Gallery Facilities Nanodevices and Microsystems Radiation Effects and High Energy Density Science Research Image Gallery...

  10. Sandia National Laboratories: Research: Materials Science: Video...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Research Image Gallery Video Gallery Facilities Nanodevices and Microsystems Radiation Effects and High Energy Density Science Research Video Gallery Exc An error...

  11. Device - Plasma Couette Experiment - Cary Forest Group - UW Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Device UW Madison Plasma Couette Experiment Device PCX HomeResearch MissionPhysics TopicsDeviceDiagnosticsContacts LinksPCX People CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation A picture of PCX plasma. The LaB6 plasma source is heated to 1400ÂşC, emitting electrons that ionize gas. Rings of permanent magnets, covered in white insulating cloth, create a multidipole magnetic field to confine the plasma. Electrode

  12. Chapter 9: Enabling Capabilities for Science and Energy | High...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Biophysics, Nuclear Physics, High Energy Physics, Fusion and Plasma Energy, and Computer And Data Science Science Area Project Title Institution Molecular Biophysics ...

  13. Energy in density gradient

    SciTech Connect (OSTI)

    Vranjes, J.; Kono, M.

    2015-01-15

    Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work, the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindrical configuration. This is of practical importance for drift wave instability in various plasmas, and, in particular, in its application in models dealing with the heating of solar corona because the instability is accompanied with stochastic heating, so the energy contained in inhomogeneity is effectively transformed into heat. It is shown that even for a rather moderate increase of the density at the axis in magnetic structures in the corona by a factor 1.5 or 3, the amount of excess energy per unit volume stored in such a density gradient becomes several orders of magnitude greater than the amount of total energy losses per unit volume (per second) in quiet regions in the corona. Consequently, within the life-time of a magnetic structure such energy losses can easily be compensated by the stochastic drift wave heating.

  14. Fusion Energy Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fusion Energy Sciences Fusion Energy Sciences Expanding the fundamental understanding of matter at very high temperatures and densities and to build the scientific foundation needed to develop a fusion energy source. Get Expertise Don Rej (505) 665-1883 Email Building the scientific foundation needed to develop a fusion energy source The mission of the DOE Office of Science's Fusion Energy Sciences (FES) program is to expand the fundamental understanding of matter at very high temperatures and

  15. Press Releases Archive | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Plasma Physics in the Chinese Academy of Sciences (ASIPP), combined the new technique with a method that the U.S. Department of Energy's Princeton Plasma Physics Laboratory ...

  16. Sandia National Laboratories: Research: Materials Science: About Us

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Science Bioscience Computing and Information Science Electromagnetics Engineering Science Geoscience Materials Science About Materials Science Research Image Gallery Video Gallery Facilities Nanodevices and Microsystems Radiation Effects and High Energy Density Science Research About Materials Science Xunhu Dai Sandia excels in innovative fundamental materials science research - developing and integrating the theoretical insights, computational simulation tools and deliberate

  17. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB{sub 6}-filament

    SciTech Connect (OSTI)

    Ueno, A.; Oguri, H.; Ikegami, K.; Namekawa, Y.; Ohkoshi, K.; Tokuchi, A.

    2010-02-15

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB{sub 6}) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 {mu}H inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 Ax140 V) and a duty factor of more than 1.5%(600 {mu}sx25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H{sup -} ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 {mu}s and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  18. Review: engineering particles using the aerosol-through-plasma method

    SciTech Connect (OSTI)

    Phillips, Jonathan; Luhrs, Claudia C; Richard, Monique

    2009-01-01

    For decades, plasma processing of materials on the nanoscale has been an underlying enabling technology for many 'planar' technologies, particularly virtually every aspect of modern electronics from integrated-circuit fabrication with nanoscale elements to the newest generation of photovoltaics. However, it is only recent developments that suggest that plasma processing can be used to make 'particulate' structures of value in fields, including catalysis, drug delivery, imaging, higher energy density batteries, and other forms of energy storage. In this paper, the development of the science and technology of one class of plasma production of particulates, namely, aerosol-through-plasma (A-T-P), is reviewed. Various plasma systems, particularly RF and microwave, have been used to create nanoparticles of metals and ceramics, as well as supported metal catalysts. Gradually, the complexity of the nanoparticles, and concomitantly their potential value, has increased. First, unique two-layer particles were generated. These were postprocessed to create unique three-layer nanoscale particles. Also, the technique has been successfully employed to make other high-value materials, including carbon nanotubes, unsupported graphene, and spherical boron nitride. Some interesting plasma science has also emerged from efforts to characterize and map aerosol-containing plasmas. For example, it is clear that even a very low concentration of particles dramatically changes plasma characteristics. Some have also argued that the local-thermodynamic-equilibrium approach is inappropriate to these systems. Instead, it has been suggested that charged- and neutral-species models must be independently developed and allowed to 'interact' only in generation terms.

  19. Education | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Education Science Education Welcome to the Science Education Department at the Princeton Plasma Physics Laboratory (PPPL), where we combine the lab's core research activities with science education programs to create a center of excellence for students, teachers and the general public. We contribute to the training of the next generation of scientists and engineers, collaborate with K-12 teachers on ways to improve science teaching using an inquiry-based approach to learning, and improve the

  20. Heavy Ion Fusion Science Virtual National Laboratory1st Quarter FY08 Milestone Report: Report Initial Work on Developing Plasma Modeling Capability in WARP for NDCX ExperimentsReport Initial work on developing Plasma Modeling Capability in WARP for NDCX Experiments

    SciTech Connect (OSTI)

    Friedman, A.; Cohen, R.H.; Grote, D.P.; Vay, J.-L.

    2007-12-10

    This milestone has been accomplished. The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) has developed and implemented an initial beam-in-plasma implicit modeling capability in Warp; has carried out tests validating the behavior of the models employed; has compared the results of electrostatic and electromagnetic models when applied to beam expansion in an NDCX-I relevant regime; has compared Warp and LSP results on a problem relevant to NDCX-I; has modeled wave excitation by a rigid beam propagating through plasma; and has implemented and begun testing a more advanced implicit method that correctly captures electron drift motion even when timesteps too large to resolve the electron gyro-period are employed. The HIFS-VNL is well on its way toward having a state-of-the-art source-to-target simulation capability that will enable more effective support of ongoing experiments in the NDCX series and allow more confident planning for future ones.

  1. MST - UW Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    MST Home UW Madison Madison Symmetric Torus MST Home MST HomeGraduate Student InformationLinksTourControl and Auxiliary SystemsPhysics TopicsDeviceResearch MissionMST People mst logo CPLA Home Directory Publications Links Internal University of Wisconsin Physics Department Research funding includes support from: Department of Energy National Science Foundation The Madison Symmetric Torus produces hot plasma for research in plasma physics and fusion power generation, the energy source of the sun.

  2. DOE New Jersey Regional High School Science Bowl! NO SCIENCE ON SATURDAY

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    LECTURE | Princeton Plasma Physics Lab 2, 2014 (All day) Science On Saturday DOE New Jersey Regional High School Science Bowl! NO SCIENCE ON SATURDAY LECTURE DUE TO THE NEW JERSEY REGIONAL SCIENCE BOWL COMPETITION, THERE WILL BE NO SCIENCE ON SATURDAY LECTURE TODAY.

  3. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect (OSTI)

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism Computational Sciences, Inc. and Advanced Energy Systems Inc. joined efforts to develop new physics and numerical models for LSP in several key areas to enhance the ability of LSP to model high energy density plasmas (HEDP). This final report details those efforts. Areas addressed in this research effort include: adding radiation transport to LSP, first in 2D and then fully 3D, extending the EMHD model to 3D, implementing more advanced radiation and electrode plasma boundary conditions, and installing more efficient implicit numerical algorithms to speed complex 2-D and 3-D computations. The new capabilities allow modeling of the dominant processes in high energy density plasmas, and further assist the development and optimization of plasma jet accelerators, with particular attention to MHD instabilities and plasma/wall interaction (based on physical models for ion drag friction and ablation/erosion of the electrodes). In the first funding cycle we implemented a solver for the radiation diffusion equation. To solve this equation in 2-D, we used finite-differencing and applied the parallelized sparse-matrix solvers in the PETSc library (Argonne National Laboratory) to the resulting system of equations. A database of the necessary coefficients for materials of interest was assembled using the PROPACEOS and ATBASE codes from Prism. The model was benchmarked against Prism's 1-D radiation hydrodynamics code HELIOS, and against experimental data obtained from HyperV's separately funded plasma jet accelerator development program. Work in the second funding cycle focused on extending the radiation diffusion model to full 3-D, continued development of the EMHD model, optimizing the direct-implicit model to speed up calculations, add in multiply ionized atoms, and improved the way boundary conditions are handled in LSP. These new LSP capabilities were then used, along with analytic calculations and Mach2 runs, to investigate plasma jet merging, plasma detachment and transport, restrike and advanced jet accelerator design. In addition, a strong linkage to diagnostic measureme

  4. Thomson Scattering Lineshape Fitting for Plasma Diagnostics

    Energy Science and Technology Software Center (OSTI)

    1994-02-04

    HFIT30 is used for interpreting lineshape (intensity versus frequency) data from Thomson and Rayleigh light scattering from a plasma, to obtain temperatures and number densities of the component species in the plasma.

  5. Princeton Plasma Physics Lab - Nanotechnology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), Adam Cohen has been named Deputy Under Secretary for Science and Energy in Washington D.C....

  6. Device - Madison Plasma Dynamo Experiment - Cary Forest Group - UW Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Device UW Madison Madison Plasma Dynamo Experiment Device MPDX HomeDynamo TutorialDeviceMPDX People MPDX Webcam CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation The Madison Plasma Dynamo Experiment (MPDX) is being constructed for investigating self-generation of magnetic fields and related processes in a large, weakly magnetized, fast flowing, and hot (conducting) plasma. When completed, a major new,

  7. Response to FESAC survey, non-fusion connections to Fusion Energy Sciences. Applications of the FES-supported beam and plasma simulation code, Warp

    SciTech Connect (OSTI)

    Friedman, A.; Grote, D. P.; Vay, J. L.

    2015-05-29

    The Fusion Energy Sciences Advisory Committee’s subcommittee on non-fusion applications (FESAC NFA) is conducting a survey to obtain information from the fusion community about non-fusion work that has resulted from their DOE-funded fusion research. The subcommittee has requested that members of the community describe recent developments connected to the activities of the DOE Office of Fusion Energy Sciences. Two questions in particular were posed by the subcommittee. This document contains the authors’ responses to those questions.

  8. Brochures | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Brochures Subscribe to RSS - Brochures The United States Department of Energy's Princeton Plasma Physics Laboratory works with collaborators across the globe to develop fusion as an energy source for the world, and conducts research along the broad frontier of plasma science and technology. Printed materials are free, accessible, and downloadable from this website. Image: Brochures PPPL Experts Fusion. Energy. Plasma. Physics. Tokamaks. Stellarators. Radioactivity. Nanotechnology. Astrophysics.

  9. Research | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research The U.S. Department of Energy's Princeton Plasma Physics Laboratory is dedicated to developing fusion as a clean and abundant source of energy and to advancing the frontiers of plasma science. The Laboratory pursues these goals through experiments and computer simulations of the behavior of plasma, the hot electrically charged gas that fuels fusion reactions and has a wide range of practical applications. Experimental Fusion Research Fusion powers the sun and stars. The process takes

  10. Neutral depletion and the helicon density limit

    SciTech Connect (OSTI)

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup ?3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 ?s. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  11. Closed inductively coupled plasma cell

    DOE Patents [OSTI]

    Manning, T.J.; Palmer, B.A.; Hof, D.E.

    1990-11-06

    A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies is disclosed. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy. 1 fig.

  12. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9 National Ignition Facility & Photon Science a new era of science a new era of experimental science laboratory experiments at the National Ignition Facility will enable researchers for the first time to study the effects on matter of extreme temperatures, pressures, and densities that exist naturally only in stars and deep inside planets. Results from this relatively new field of research, known as high-energy- density (hed) science, will mark the dawn of a new era of experimental science.

  13. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4 Plasma Physics By leveraging plasma under extreme conditions, we concentrate on solving ... smuggled nuclear materials, advancing weapons physics and generating fusion energy. ...

  14. NNSA announces winners of Stewardship Science Academic Programs...

    National Nuclear Security Administration (NNSA)

    during this year's session on topics including low energy nuclear science, properties of materials under extreme conditions, high energy density physics, and predictive science. ...

  15. Outreach, Community Events & Festivals | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Outreach, Community Events & Festivals The Science Education Department at PPPL has a variety of portable scientific demonstrations, laboratories and experiments that explain the beauty and excitement of science, fusion and plasmas. In the recent past, we've set up shop at: Princyclopedia Communiversity Princeton University's Community & Staff day Science Teacher's Day and the Plasma Sciences Expo USA Science & Engineering Festival 2013 Open House Check back regularly to find out

  16. Creating, Diagnosing and Controlling High-energy-density Matter with Lasers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | Princeton Plasma Physics Lab October 22, 2013, 3:00pm to 4:15pm Colloquia MBG Auditorium Creating, Diagnosing and Controlling High-energy-density Matter with Lasers Dr. Yuan Ping Lawrence Livermore National Laboratory Abstract: PDF icon COLL.10.22.13A.pdf *** PLEASE NOTE SPECIAL DATE AND TIME OF THIS COLLOQUIUM *** Since their invention in 1960's, lasers with power spanning from KiloWatt to PetaWatt have been widely used in almost every branch of science, leading to numerous discoveries

  17. Science and Science Fiction

    ScienceCinema (OSTI)

    Scherrer, Robert [Vanderbilt University, Nashville, Tennessee, United States

    2009-09-01

    I will explore the similarities and differences between the process of writing science fiction and the process of 'producing' science, specifically theoretical physics. What are the ground rules for introducing unproven new ideas in science fiction, and how do they differ from the corresponding rules in physics? How predictive is science fiction? (For that matter, how predictive is theoretical physics?) I will also contrast the way in which information is presented in science fiction, as opposed to its presentation in scientific papers, and I will examine the relative importance of ideas (as opposed to the importance of the way in which these ideas are presented). Finally, I will discuss whether a background as a research scientist provides any advantage in writing science fiction.

  18. Science Briefs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Briefs /newsroom/_assets/images/newsroom-icon.jpg Science Briefs Read in detail about specific Los Alamos science achievements, and the honors our scientists are accruing. Science Briefs - 2016» Science Briefs - 2015» Science Briefs - 2014» Science Briefs - 2013» Science Briefs - 2012» Science Briefs - 2011» Shown are time lapse images of supercritical CO2 displacing water in a fracture etched into a shale micromodel. The white, blue and gray colors represent supercritical CO2,

  19. Science Briefs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Briefs newsroomassetsimageslegacy-icon-short.jpg Science Briefs Read in detail about specific Los Alamos science achievements, and the honors our scientists are...

  20. Aerodynamic Focusing Of High-Density Aerosols

    SciTech Connect (OSTI)

    Ruiz, D. E.; Fisch, Nathaniel

    2014-02-24

    High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1#22; m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

  1. Institute for Materials Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Science Institute for Materials Science x

  2. Greg W Hammett | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Greg W Hammett Principal Research Physicist, Plasma Physics Laboratory. Lecture Dr. Hammett is a principal research physicist at the Princeton Plasma Physics Laboratory (PPPL), and a lecturer in the Department of Astrophysical Sciences, Program in Plasma Physics, at Princeton University. He was selected a fellow of the American Physical Society in 1997. Dr. Hammett specializes in computational and theoretical studies of the complex physics of plasma turbulence. He and his collaborators developed

  3. Plasma Simulation Program

    SciTech Connect (OSTI)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a critical impediment to successful operation of machines like ITER. If disruptions prove unable to be avoided, their associated dynamics and effects will be addressed in the next phase of the FSP.

  4. Science Events

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Science Events Learn about our science by coming to Frontiers in Science lectures, catch Cafe Scientific events in your community, or come to sicence events at the Bradbury...

  5. Development and Optimization of Modular Hybrid Plasma Reactor...

    Office of Scientific and Technical Information (OSTI)

    Optimization of Modular Hybrid Plasma Reactor N A 36 MATERIALS SCIENCE INL developed a bench-scale, modular hybrid plasma system for gas-phase nanomaterials synthesis. The system...

  6. Plasma diagnostic reflectometry

    SciTech Connect (OSTI)

    Cohen, B.I.; Afeyan, B.B.; Garrison, J.C.; Kaiser, T.B.; Luhmann, N.C. Jr.; Domier, C.W.; Chou, A.E.; Baang, S.

    1996-02-26

    Theoretical and experimental studies of plasma diagnostic reflectometry have been undertaken as a collaborative research project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Plasma Diagnostics Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. Theoretical analyses have explored the basic principles of reflectometry to understand its limitations, to address specific gaps in the understanding of reflectometry measurements in laboratory experiments, and to explore extensions of reflectometry such as ultra-short-pulse reflectometry. The theory has supported basic laboratory reflectometry experiments where reflectometry measurements can be corroborated by independent diagnostic measurements.

  7. Materials Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Science /science-innovation/_assets/images/icon-science.jpg Materials Science National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. Materials Physics and Applications» Materials Science and Technology» Institute for Materials Science» Materials Science Rob Dickerson uses a state-of-the-art transmission electron microscope at

  8. Honey, I Shrunk the Plasma: Studying Astrophysical Processes in Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Experiments | Princeton Plasma Physics Lab February 14, 2015, 9:30am to 11:00am Science On Saturday MBG Auditorium Honey, I Shrunk the Plasma: Studying Astrophysical Processes in Laboratory Experiments Dr. Clayton Myers, Associate Research Physicist PPPL Abstract: PDF icon Myers.pdf Science on Saturday, 14FEB2015, "Honey, I Shrunk the Plasma: Studying Astrophysical Processess in Laboratory Experiments", Dr. Clayton Myers, PPPL Contact Information Website: Science on Saturday

  9. Density Functional Study of Au-n110(n = 3-5) Clusters on Relaxed...

    Office of Scientific and Technical Information (OSTI)

    Subject: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DENSITY FUNCTIONAL METHOD; GOLD; ADSORPTION; GRAPHITE; SORPTIVE PROPERTIES ENVIRONMENTAL MOLECULAR SCIENCES ...

  10. Merging of high speed argon plasma jets

    SciTech Connect (OSTI)

    Case, A.; Messer, S.; Brockington, S.; Wu, L.; Witherspoon, F. D.; Elton, R.

    2013-01-15

    Formation of an imploding plasma liner for the plasma liner experiment (PLX) requires individual plasma jets to merge into a quasi-spherical shell of plasma converging on the origin. Understanding dynamics of the merging process requires knowledge of the plasma phenomena involved. We present results from the study of the merging of three plasma jets in three dimensional geometry. The experiments were performed using HyperV Technologies Corp. 1 cm Minirailguns with a preionized argon plasma armature. The vacuum chamber partially reproduces the port geometry of the PLX chamber. Diagnostics include fast imaging, spectroscopy, interferometry, fast pressure probes, B-dot probes, and high speed spatially resolved photodiodes, permitting measurements of plasma density, temperature, velocity, stagnation pressure, magnetic field, and density gradients. These experimental results are compared with simulation results from the LSP 3D hybrid PIC code.

  11. PLASMA PHYSICS AND FUSION TECHNOLOGY; GRAPHITE; CREEP; PHYSICAL...

    Office of Scientific and Technical Information (OSTI)

    creep of graphite) Kennedy, C.R. 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; GRAPHITE; CREEP; PHYSICAL RADIATION EFFECTS; JAPAN; MEETINGS; TRAVEL; ASIA; CARBON;...

  12. PPPL's dynamic diagnostic duo | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    over 30 years and have always admired their scientific work and polite demeanor," said Philip Efthimion, who heads the Plasma Science and Technology Department at PPPL. The two...

  13. Control of focusing forces and emittances in plasma-based accelerators using near-hollow plasma channels

    SciTech Connect (OSTI)

    Schroeder, C. B.; Esarey, E.; Benedetti, C.; Leemans, W. P.

    2013-08-15

    A near-hollow plasma channel, where the plasma density in the channel is much less than the plasma density in the walls, is proposed to provide independent control over the focusing and accelerating forces in a plasma accelerator. In this geometry the low density in the channel contributes to the focusing forces, while the accelerating fields are determined by the high density in the channel walls. The channel also provides guiding for intense laser pulses used for wakefield excitation. Both electron and positron beams can be accelerated in a nearly symmetric fashion. Near-hollow plasma channels can effectively mitigate emittance growth due to Coulomb scattering for high-energy physics applications.

  14. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Gorbatkin, Steven M. (Oak Ridge, TN); Berry, Lee A. (Oak Ridge, TN)

    1991-01-01

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.

  15. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.

    1991-07-16

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.

  16. ARM - Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govScience Science Research Themes Research Highlights Journal Articles Collaborations Atmospheric System Research (ASR) Earth System Modeling Regional & Global Climate Modeling Terrestrial Ecosystem Science Performance Metrics User Meetings Past ARM Science Team Meetings ASR Meetings Accomplishments Accomplishments in Atmospheric Science, 2008-2013 (PDF, 7.4MB) ARM Accomplishments from the Science Program and User Facility, 1989-2008 (PDF, 696KB) Science New C-band scanning ARM

  17. Fusion Science to Prepare

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DIII-D Explorations of Fusion Science to Prepare for ITER and FNSF Dr. Richard Buttery General Atomics Tuesday, Dec 10, 2013 - 11:00AM MBG AUDITORIUM Refreshments at 10:45AM The PrinceTon Plasma Physics laboraTory is a U.s. DeParTmenT of energy faciliTy Recent DIII-D research has provided significant new in- formation for the physics basis of key scientific issues for successful operation of ITER and future steady state fu- sion tokamaks, including control of edge localized modes (ELMs), plasma

  18. Princeton Plasma Physics Lab - Magnetic reconnection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    can learn a lot of solar and space science, as well as astrophysics, through the common language of plasma physics," he said.

    Reconnection can have powerful consequences...

  19. NO SCIENCE ON SATURDAY LECTURE- Department of Energy New Jersey Regional

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    High School Science Bowl | Princeton Plasma Physics Lab 0, 2016 (All day) PPPL NO SCIENCE ON SATURDAY LECTURE- Department of Energy New Jersey Regional High School Science Bowl

  20. INTERACTION OF MUON BEAM WITH PLASMA DEVELOPED DURING IONIZATION COOLING

    SciTech Connect (OSTI)

    S. Ahmed, D. Kaplan, T. Roberts, L. Spentzouris, K. Beard

    2012-07-01

    Particle-in-cell simulations involving the interaction of muon beam (peak density 10{sup 18} m{sup 3}) with Li plasma (ionized medium) of density 10{sup 16}-10{sup 22} m{sup -3} have been performed. This study aimed to understand the effects of plasma on an incoming beam in order to explore scenario developed during the process of ionization cooling. The computer code takes into account the self-consistent electromagnetic effects of beam interacting with plasma. This study shows that the beam can pass through the plasma of densities four order of magnitude higher than its peak density. The low density plasmas are wiped out by the beam, however, the resonance is observed for densities of similar order. Study reveals the signature of plasma wakefield acceleration.

  1. Laboratory, Valles Caldera sponsor environmental science event

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Environmental science event Laboratory, Valles Caldera sponsor environmental science event The Summer Environmental Science Program lets students explore a wide range of science-related topics in the Valles Caldera National Preserve. July 9, 2009 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new

  2. Detection Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemistry for Measurement and Detection Science Chemistry for Measurement and Detection Science Project Description Chemistry used in measurement and detection science plays a crucial role in the Laboratory's Science of Signatures scientific thrust. Measurement and detection science areas that require chemistry include nuclear and radiological, materials, biological, energy, climate, and space. Los Alamos scientists integrate chemical-science capabilities to ensure that the Laboratory can

  3. Chemical Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemical Science /science-innovation/_assets/images/icon-science.jpg Chemical Science National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. Actinide Chemistry» Modeling & Simulation» Synthetic and Mechanistic Chemistry» Chemistry for Measurement and Detection Science» Chemical Researcher Jeff Pietryga shows two vials of

  4. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Highlights Science Highlights Print Science Highlights Featured scientific research based on publications resulting from work done at the ALS. Highlights are nominated by management and beamline scientists for their scientific significance. Current highlights (2004-present), highlight archives (1995-2004), and Summary Slides of ALS Science Highlights are also available. Science Briefs Short reports on recent research submitted by ALS beamline scientists and users. Science Cafés Informal

  5. Robert J Goldston | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Robert J Goldston Professor of Astrophysical Sciences. former Director, PPPL Robert Goldston is a professor of Astrophysical Sciences at Princeton University and an international leader in the fields of plasma physics and magnetic fusion energy. From 1997 to 2009 he served as Director of PPPL. He is the author of 220 papers in journals and conference proceedings, and in 1995 co- authored with Paul Rutherford the textbook "Introduction to Plasma Physics." He is a contributing author to

  6. Nuclear Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nuclear Science Nuclear Science Experimental and theoretical nuclear research carried out at NERSC is driven by the quest for improving our understanding of the building blocks of...

  7. Accelerator Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Accelerator Science Accelerator Science ReframAccelerator.jpg Particle accelerators are among the largest, most complex, and most important scientific instruments in the world....

  8. Computer Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cite Seer Department of Energy provided open access science research citations in chemistry, physics, materials, engineering, and computer science IEEE Xplore Full text...

  9. Science Gateways

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    About Science Gateways A science gateway is a web-based interface to access HPC computers ... perform shared computations, and generally interact with NERSC resources over the web. ...

  10. Is sustainability science really a science?

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Is sustainability science really a science? Is sustainability science really a science? The team's work shows that although sustainability science has been growing explosively ...

  11. Material Science and Nuclear Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Material Science and Nuclear Science Material Science and Nuclear Science National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. The Lab's four Science Pillars harness capabilities for solutions to threats- on national and global scales. Contact thumbnail of Business Development Business Development Richard P. Feynman Center for Innovation

  12. Links - Plasma Couette Experiment - Cary Forest Group - UW Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Links UW Madison Plasma Couette Experiment Links PCX HomeResearch MissionPhysics TopicsDeviceDiagnosticsContacts LinksPCX People CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation No links yet

  13. PPPL Experts | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    PPPL Experts Fusion. Energy. Plasma. Physics. Tokamaks. Stellarators. Radioactivity. Nanotechnology. Astrophysics. Computational simulations. Vacuum technology. Materials Science. Electronics. STEM education. These are some of the areas of expertise of staff at the Princeton Plasma Physics Laboratory. PPPL is devoted to creating new knowledge about the physics of plasmas - ultra-hot, charged gases - and to developing practical solutions for the creation of fusion energy. In addition, results of

  14. Allan H Reiman | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Allan H Reiman Principal Research Physicist, Plasma Physics Laboratory. Lecture Allan Reiman is head of the stellarator theory group in the Theory Department. He is a Principal Research Physicist in the Theory Department, a Distinguished Research Fellow at the plasma physics laboratory, and a Lecturer with Rank of Professor in the Department of Astrophysical Sciences at Princeton University. He is a Fellow of the American Physical Society. From 1997 to 2000 he headed the plasma configuration

  15. Ronald C Davidson | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ronald C Davidson Professor of Astrophysical Sciences, Emeritus. Senior Astrophysicist Ronald Davidson has made numerous fundamental theoretical contributions to pure and applied plasma physics, including nonlinear plasma dynamics and collective interactions; physics of non-neutral plasmas; kinetic equilibrium and stability properties; and intense charged particle beam propagation in high energy accelerators. Professor Davidson served as director of PPPL from 1991 to 1996 and as director of the

  16. Daren P Stotler | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Daren P Stotler Principal Research Physicist, Science Focus Group Head, Plasma-B Dr. Daren Stotler is a Principal Research Physicist in the Theory Department primarily interested in the interaction between plasmas and their material surroundings. In an experiment or reactor, those interactions result in the release of atoms and molecules into the plasma. These electrically neutral particles can freely cross the magnetic field lines of the experiment, perhaps resulting in a deterioration of its

  17. John A Krommes | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Krommes Principal Research Physicist, Plasma Physics Laboratory. Lecturer with Rank of Professor in Astrophysical Sciences Prof. Krommes is a Principal Research Physicist at the Plasma Physics Laboratory, a Lecturer With the Rank of Professor in the Dept. of Astrophysics (Plasma Physics Program), and an Associated Faculty Member of Princeton's Program in Applied and Computational Mathematics. He received his BS degree (summa cum laude) in 1971 from the Pennsylvania State University, where he

  18. American Fusion News | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    American Fusion News General Atomics (GA) December 4, 2012 The Scorpion's Strategy: "Catch and Subdue" December 4, 2012 Frozen Bullets Tame Unruly Edge Plasmas in Fusion Experiment February 15, 2012 General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement See All Massachusetts Institute of Technology (MIT) April 5, 2013 Applying physics, teamwork to fusion energy science February 22, 2013 A Tour of Plasma Physics in Downtown Cambridge December 4, 2012 Placing

  19. Staff Research Physicist (X-Ray Spectroscopy) | Princeton Plasma...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of X-ray spectrometers for high energy density plasma at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL, Livermore, California). In...

  20. Statistical Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    6 Statistical Sciences Applying statistical reasoning and rigor to multidisciplinary scientific investigations Contact Us Group Leader Joanne Wendelberger Email Deputy Group Leader James R. Gattiker Email Group Administrator LeeAnn Martinez (505) 667-3308 Email Statistical Sciences Statistical Sciences provides statistical reasoning and rigor to multidisciplinary scientific investigations and development, application, and communication of cutting-edge statistical sciences research. Statistical

  1. Explosives Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Explosives Science Explosives Science Current efforts in explosives science cover many areas critical to national security. One particular area is the need for countermeasures against explosive threats. v Comprehensive explosives process Los Alamos National Laboratory offers a comprehensive explosives process. This process leverages entire technical divisions dedicated to explosives science. Los Alamos scientists combine advanced expertise and capabilities with modern facilities. These assets

  2. Neutrino oscillations in a turbulent plasma

    SciTech Connect (OSTI)

    Mendonça, J. T.; Haas, F.

    2013-07-15

    A new model for the joint neutrino flavor and plasma oscillations is introduced, in terms of the dynamics of the neutrino flavor polarization vector in a plasma background. Fundamental solutions are found for both time-invariant and time-dependent media, considering slow and fast variations of the electron plasma density. The model is shown to be described by a generalized Hamiltonian formalism. In the case of a broad spectrum of electron plasma waves, a statistical approach indicates the shift of both equilibrium value and frequency oscillation of flavor coherence, due to the existence of a turbulent plasma background.

  3. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Highlights Print Science Highlights Featured scientific research based on publications resulting from work done at the ALS. Highlights are nominated by management and beamline scientists for their scientific significance. Current highlights (2004-present), highlight archives (1995-2004), and Summary Slides of ALS Science Highlights are also available. Science Briefs Short reports on recent research submitted by ALS beamline scientists and users. Science Cafés Informal lecture series

  4. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Highlights Print Science Highlights Featured scientific research based on publications resulting from work done at the ALS. Highlights are nominated by management and beamline scientists for their scientific significance. Current highlights (2004-present), highlight archives (1995-2004), and Summary Slides of ALS Science Highlights are also available. Science Briefs Short reports on recent research submitted by ALS beamline scientists and users. Science Cafés Informal lecture series

  5. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Highlights Print Science Highlights Featured scientific research based on publications resulting from work done at the ALS. Highlights are nominated by management and beamline scientists for their scientific significance. Current highlights (2004-present), highlight archives (1995-2004), and Summary Slides of ALS Science Highlights are also available. Science Briefs Short reports on recent research submitted by ALS beamline scientists and users. Science Cafés Informal lecture series

  6. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Highlights Print Science Highlights Featured scientific research based on publications resulting from work done at the ALS. Highlights are nominated by management and beamline scientists for their scientific significance. Current highlights (2004-present), highlight archives (1995-2004), and Summary Slides of ALS Science Highlights are also available. Science Briefs Short reports on recent research submitted by ALS beamline scientists and users. Science Cafés Informal lecture series

  7. Explore Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Explore Explore Science Create your own science adventure by exploring our varied exhibits, and learn what inspired our scientists, engineers and technicians to discover new things. August 18, 2014 boys conducting experiment [Science is] a great game. It is inspiring and refreshing. The playing field is the universe itself. -I.I. Rabi Science is thinking in an organized way about things. You don't need a license or permission to practice science. Scientists are interested in just about anything

  8. Plasma valve

    DOE Patents [OSTI]

    Hershcovitch, Ady (Mount Sinai, NY); Sharma, Sushil (Hinsdale, IL); Noonan, John (Naperville, IL); Rotela, Elbio (Clarendon Hills, IL); Khounsary, Ali (Hinsdale, IL)

    2003-01-01

    A plasma valve includes a confinement channel and primary anode and cathode disposed therein. An ignition cathode is disposed adjacent the primary cathode. Power supplies are joined to the cathodes and anode for rapidly igniting and maintaining a plasma in the channel for preventing leakage of atmospheric pressure through the channel.

  9. Dynamo Tutorial - Madison Plasma Dynamo Experiment - Cary Forest Group - UW

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Physics Dynamo Tutorial UW Madison Madison Plasma Dynamo Experiment Dynamo Tutorial MPDX HomeDynamo TutorialDeviceMPDX People MPDX Webcam CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation Tutorials on the Workings of a Plasma Dynamo: APS 2009 Tutorial Nice 2010 Tutorial Field Line Movie Alpha Effect Movie Omega Effect Movie

  10. Boundary Plasma Turbulence Simulations for Tokamaks

    SciTech Connect (OSTI)

    Xu, X.; Umansky, M.; Dudson, B.; Snyder, P

    2008-05-15

    The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T{sub e}; T{sub i}) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

  11. News Archive | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Archive Subscribe to Princeton Plasma Physics Laboratory News March 9, 2016 DOE's Ed Synakowski traces key discoveries in the quest for fusion energy By Jeanne Jackson DeVoe The DOE's Associate Director of Science for Fusion Energy Sciences Ed Synakowski discusses the "aha" moments in the development of fusion energy at a March 5 Ronald E. Hatcher Science on Saturday lecture. The path to creating sustainable fusion energy as a clean, abundant and affordable source of electric energy

  12. SCIENCE ON SATURDAY- "The Large Hadron Collider: big science for big

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    questions" | Princeton Plasma Physics Lab January 5, 2013, 9:30am Science On Saturday MBG Auditorium SCIENCE ON SATURDAY- "The Large Hadron Collider: big science for big questions" Professor James Olsen Department of Physics, Princeton University Science on Saturday is a series of lectures given by scientists, mathematicians, and other professionals involved in cutting-edge research. Held on Saturday mornings throughout winter, the lectures are geared toward high school

  13. Science Education Blog | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    "What is Fusion" features interviews with PPPL physicists on location and employs animation to allow the scientists to explain magnetic fusion. The eight-minute "Fusion Energy...

  14. Princeton Plasma Physics Lab - Surface science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the complex edge region, an important research area in fusion energy research. "We're learning more and more that to some extent the edge is the dog that wags the tail of the...

  15. 2013 Science Bowl | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bowl View larger image 13 PR 0222 189 View larger image 13 PR 0222 194 View larger image 13 PR 0222 189 View larger image 13 PR 0222 195 View larger image 13 PR 0222 200 View larger image 13 PR 0222 206 View larger image Winners WWPS F View larger image 2 Nd Place Bergen View larger image 3 Rd Place State View larger image Winners View larger image 2 Nd Place JDroids View larger image 3 Rd Place Thomas Grover

  16. Surface science | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    two phases of matter, such as solid to liquid or liquid to gas. Laboratory Director Stewart Prager heralds start of new era with NSTX-U and looks to future projects in "State of...

  17. Science literacy | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    issues. COLLOQUIUM: Chance, Necessity, and the Origins of Life Earth's 4.5 billion year history is a complex tale of deterministic physical and chemical processes, as well as...

  18. Linear accelerator design study with direct plasma injection scheme for warm dense matter

    SciTech Connect (OSTI)

    Kondo, K.; Kanesue, T; Okamura, M.

    2011-03-28

    Warm Dense Matter (WDM) is a challenging science field, which is related to heavy ion inertial fusion and planetary science. It is difficult to expect the behavior because the state with high density and low temperature is completely different from ideal condition. The well-defined WDM generation is required to understand it. Moderate energy ion beams ({approx} MeV/u) slightly above Bragg peak is an advantageous method for WDM because of the uniform energy deposition. Direct Plasma Injection Scheme (DPIS) with a Interdigital H-mode (IH) accelerator has a potential for the beam parameter. We show feasible parameters of the IH accelerator for WDM. WDM physics is a challenging science and is strongly related to Heavy Ion Fusion science. WDM formation by Direct Plasma Injection Scheme (DPIS) with IH accelerator, which is a compact system, is proposed. Feasible parameters for IH accelerator are shown for WDM state. These represents that DPIS with IH accelerator can access a different parameter region of WDM.

  19. Plasma response to electron energy filter in large volume plasma device

    SciTech Connect (OSTI)

    Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.; Srivastava, P. K.; Singh, S. K.; Singh, R.; Kaw, P. K. [Institute for Plasma Research, Gandhinagar, 382 428 Gujarat (India)] [Institute for Plasma Research, Gandhinagar, 382 428 Gujarat (India)

    2013-12-15

    An electron energy filter (EEF) is embedded in the Large Volume Plasma Device plasma for carrying out studies on excitation of plasma turbulence by a gradient in electron temperature (ETG) described in the paper of Mattoo et al. [S. K. Mattoo et al., Phys. Rev. Lett. 108, 255007 (2012)]. In this paper, we report results on the response of the plasma to the EEF. It is shown that inhomogeneity in the magnetic field of the EEF switches on several physical phenomena resulting in plasma regions with different characteristics, including a plasma region free from energetic electrons, suitable for the study of ETG turbulence. Specifically, we report that localized structures of plasma density, potential, electron temperature, and plasma turbulence are excited in the EEF plasma. It is shown that structures of electron temperature and potential are created due to energy dependence of the electron transport in the filter region. On the other hand, although structure of plasma density has origin in the particle transport but two distinct steps of the density structure emerge from dominance of collisionality in the source-EEF region and of the Bohm diffusion in the EEF-target region. It is argued and experimental evidence is provided for existence of drift like flute Rayleigh-Taylor in the EEF plasma.

  20. Global Simulation of Plasma Microturbulence at the Petascale & Beyond

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Optimizing the GTC Code for Blue Gene/Q): ALCF-2 Early Science Program Technical Report (Technical Report) | SciTech Connect Global Simulation of Plasma Microturbulence at the Petascale & Beyond (Optimizing the GTC Code for Blue Gene/Q): ALCF-2 Early Science Program Technical Report Citation Details In-Document Search Title: Global Simulation of Plasma Microturbulence at the Petascale & Beyond (Optimizing the GTC Code for Blue Gene/Q): ALCF-2 Early Science Program Technical Report

  1. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    SciTech Connect (OSTI)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S.

    2015-04-15

    A recent low gas-fill density (0.6?mg/cc {sup 4}He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6?mg/cc {sup 4}He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth.

  2. Science Briefs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    feed-image Digg: ALSBerkeleyLab Facebook Page: 208064938929 Flickr: advancedlightsource Twitter: AdvLightSource YouTube: AdvancedLightSource Home Science Highlights Science Briefs Science Briefs ALS Science Briefs are short (200 words maximum) descriptions of recently published ALS-related work. These "brief" highlights also include one image, a caption (50 words), and the publication citation. All ALS users and beamline scientists are invited to fill out the short submission form here

  3. Science Facilities

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Facilities /science-innovation/_assets/images/icon-science.jpg Science Facilities The focal point for basic and applied R&D programs with a primary focus on energy but also encompassing medical, biotechnology, high-energy physics, and advanced scientific computing programs. Center for Integrated Nanotechnologies» Dual Axis Radiographic Hydrodynamic Test Facility (DARHT)» Electron Microscopy Lab» Ion Beam Materials Lab» Isotope Production Facility» Los Alamos Neutron Science Center»

  4. Science Programs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Programs /science-innovation/_assets/images/icon-science.jpg Science Programs The focal point for basic and applied R&D programs with a primary focus on energy but also encompassing medical, biotechnology, high-energy physics, and advanced scientific computing programs. Applied Energy Programs» Civilian Nuclear Programs» Laboratory Directed Research & Development» Office of Science»

  5. Big Science

    ScienceCinema (OSTI)

    Dr. Thomas Zacharia

    2010-01-08

    Big science seeks big solutions for the most urgent problems of our times. Video courtesy Cray, Inc.

  6. **NO SCIENCE ON SATURDAY TODAY** NJ Regional High School Science Bowl |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Princeton Plasma Physics Lab 3, 2013, 8:00am Science Education Lab-wide Event **NO SCIENCE ON SATURDAY TODAY** NJ Regional High School Science Bowl Teams of students are invited to participate in the Department of Energy's National Science Bowl Competition. Each year PPPL hosts the New Jersey Regional Science Bowl which decides which teams from the local area can continue onto the national competition in Washington, D.C. The Science Bowl is a double elimination contest with oral question and

  7. Plasma source ion implantation research and applications at Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Munson, C.P.; Faehl, R.J.; Henins, I.

    1996-12-31

    Plasma Source Ion Implantation research at Los Alamos Laboratory includes direct investigation of the plasma and materials science involved in target surface modification, numerical simulations of the implantation process, and supporting hardware engineering. Target materials of Al, Cr, Cu-Zn, Mg, Ni, Si, Ti, W, and various Fe alloys have been processed using plasmas produced from Ar, NH{sub 3}, N{sub 2}, CH{sub 4}, and C{sub 2}H{sub 2} gases. Individual targets with surface areas as large as {approximately}4 m{sup 2}, or weighing up to 1200 kg, have been treated in the large LANL facility. In collaboration with General Motors and the University of Wisconsin, a process has been developed for application of hard, low friction, diamond-like-carbon layers on assemblies of automotive pistons. Numerical simulations have been performed using a 2{1/2}-D particle- in-cell code, which yields time-dependent implantation energy, dose, and angle of arrival for ions at the target surface for realistic geometries. Plasma source development activities include the investigation of pulsed, inductively coupled sources capable of generating highly dissociated N{sup +} with ion densities n{sub i} {approximately} 10{sup 11}/cm{sup 3}, at {approximately}100 W average input power. Cathodic arc sources have also been used to produce filtered metallic and C plasmas for implantation and deposition either in vacuum, or in conjunction with a background gas for production of highly adherent ceramic coatings.

  8. Huazhong Science Technology University Yongtai Science Technology...

    Open Energy Info (EERE)

    Huazhong Science Technology University Yongtai Science Technology Co Ltd Jump to: navigation, search Name: Huazhong Science & Technology University Yongtai Science & Technology Co...

  9. Application of Plasma Waveguides to High Energy Accelerators

    SciTech Connect (OSTI)

    Milchberg, Howard M

    2013-03-30

    The eventual success of laser-plasma based acceleration schemes for high-energy particle physics will require the focusing and stable guiding of short intense laser pulses in reproducible plasma channels. For this goal to be realized, many scientific issues need to be addressed. These issues include an understanding of the basic physics of, and an exploration of various schemes for, plasma channel formation. In addition, the coupling of intense laser pulses to these channels and the stable propagation of pulses in the channels require study. Finally, new theoretical and computational tools need to be developed to aid in the design and analysis of experiments and future accelerators. Here we propose a 3-year renewal of our combined theoretical and experimental program on the applications of plasma waveguides to high-energy accelerators. During the past grant period we have made a number of significant advances in the science of laser-plasma based acceleration. We pioneered the development of clustered gases as a new highly efficient medium for plasma channel formation. Our contributions here include theoretical and experimental studies of the physics of cluster ionization, heating, explosion, and channel formation. We have demonstrated for the first time the generation of and guiding in a corrugated plasma waveguide. The fine structure demonstrated in these guides is only possible with cluster jet heating by lasers. The corrugated guide is a slow wave structure operable at arbitrarily high laser intensities, allowing direct laser acceleration, a process we have explored in detail with simulations. The development of these guides opens the possibility of direct laser acceleration, a true miniature analogue of the SLAC RF-based accelerator. Our theoretical studies during this period have also contributed to the further development of the simulation codes, Wake and QuickPIC, which can be used for both laser driven and beam driven plasma based acceleration schemes. We will continue our development of advanced simulation tools by modifying the QuickPIC algorithm to allow for the simulation of plasma particle pick-up by the wake fields. We have also performed extensive simulations of plasma slow wave structures for efficient THz generation by guided laser beams or accelerated electron beams. We will pursue experimental studies of direct laser acceleration, and THz generation by two methods, ponderomotive-induced THz polarization, and THz radiation by laser accelerated electron beams. We also plan to study both conventional and corrugated plasma channels using our new 30 TW in our new lab facilities. We will investigate production of very long hydrogen plasma waveguides (5 cm). We will study guiding at increasing power levels through the onset of laser-induced cavitation (bubble regime) to assess the role played by the preformed channel. Experiments in direct acceleration will be performed, using laser plasma wakefields as the electron injector. Finally, we will use 2-colour ionization of gases as a high frequency THz source (<60 THz) in order for femtosecond measurements of low plasma densities in waveguides and beams.

  10. Snowflake Science

    Broader source: Energy.gov [DOE]

    Physicists at the Princeton Plasma Physics Laboratory are using a device called a "snowflake divertor” to solve one of the grand challenges of magnetic fusion.

  11. Laser beat wave excitation of terahertz radiation in a plasma slab

    SciTech Connect (OSTI)

    Chauhan, Santosh; Parashar, Jetendra

    2014-10-15

    Terahertz (THz) radiation generation by nonlinear mixing of lasers, obliquely incident on a plasma slab is investigated. Two cases are considered: (i) electron density profile is parabolic but density peak is below the critical density corresponding to the beat frequency, (ii) plasma boundaries are sharp and density is uniform. In both cases, nonlinearity arises through the ponderomotive force that gives rise to electron drift at the beat frequency. In the case of inhomogeneous plasma, non zero curl of the nonlinear current density gives rise to electromagnetic THz generation. In case of uniform plasma, the sharp density variation at the plasma boundaries leads to radiation generation. In a slab width of less than a terahertz wavelength, plasma density one fourth of terahertz critical density, laser intensities ?10{sup 17?}W/cm{sup 2} at 1??m, one obtains the THz intensity ?1?GW/cm{sup 2} at 3 THz radiation frequency.

  12. Climate & Earth Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Human-Induced Climate Change Reduces Chance of Flooding in Okavango Delta Energy Science Engineering Science Environmental Science Fusion Science Math & Computer Science Nuclear...

  13. Science DMZ for ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ @ UF Science DMZ @ CU...

  14. Stellar science unveiled at space conference

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Stellar science unveiled at space conference Stellar science unveiled at space conference The Laboratory will be represented in more than 20 papers to be given at the 42nd Lunar and Planetary Science Conference in Houston. March 8, 2011 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

  15. Vortex stabilized electron beam compressed fusion grade plasma

    SciTech Connect (OSTI)

    Hershcovitch, Ady

    2014-03-19

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  16. Science on Saturday: Starlight Detectives: How Astronomers, Inventors, and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Eccentrics Discovered the Modern Universe | Princeton Plasma Physics Lab January 9, 2016, 9:30am Science On Saturday Princeton Plasma Physics Laboratory, MBG Auditorium Science on Saturday: Starlight Detectives: How Astronomers, Inventors, and Eccentrics Discovered the Modern Universe Professor Alan Hirshfeld University of Massachusetts Abstract: PDF icon 01 Hirshfeld.pdf Science_on_Saturday09Jan2016_A.Hirshfield Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov

  17. Science DMZ Case Studies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science DMZ Case Studies Science DMZ @ UF Science DMZ @ CU Science DMZ @ Penn & VTTI Science DMZ @ NOAA Science DMZ @ NERSC Science DMZ @ ALS Multi-facility Workflow Case Study...

  18. L-Mode Plasmas in Alcator C-Mod I. Cziegler, J. L. Terry, B....

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    C-Mod I. Cziegler, J. L. Terry, B. LaBombard MIT - Plasma Science and Fusion Center APS Division of Plasma Physics Orlando FL, November 2007 Background and Motivation Both L-...

  19. Plasma Sources Sci. Technol.

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sources Sci. Technol. 6 (1997) 492-498. Printed in the UK PII: S0963-0252(97)87196-4 Impurities, temperature and density in a miniature electrostatic plasma and current source D J Den Hartog†, D J Craig†, G Fiksel‡ and J S Sarff‡ † Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706, USA ‡ Sterling Scientific, Inc., 1415 Rutledge Street, Madison, WI 53703, USA Received 23 October 1996, in final form 25 July 1997 Abstract. We have

  20. Method of accelerating photons by a relativistic plasma wave

    DOE Patents [OSTI]

    Dawson, John M. (Pacific Palisades, CA); Wilks, Scott C. (Santa Monica, CA)

    1990-01-01

    Photons of a laser pulse have their group velocity accelerated in a plasma as they are placed on a downward density gradient of a plasma wave of which the phase velocity nearly matches the group velocity of the photons. This acceleration results in a frequency upshift. If the unperturbed plasma has a slight density gradient in the direction of propagation, the photon frequencies can be continuously upshifted to significantly greater values.

  1. A restoration model of distorted electron density in wave-cutoff probe measurement

    SciTech Connect (OSTI)

    Jun, Hyun-Su Lee, Yun-Seong

    2014-02-15

    This study investigates the problem of electron density distortion and how the density can be restored in a wave-cutoff probe. Despite recent plasma diagnostics research using a wave-cutoff probe, the problem of electron density distortion caused by plasma conditions has not been resolved. Experimental results indicate that electron density measured using the wave-cutoff method is highly susceptible to variations in the probe tip gap. This electron density distortion is caused by the bulk plasma disturbance between probe tips, and it must be removed for calculating the absolute electron density. To do this, a detailed analytic model was developed using the power balance equation near probe tips. This model demonstrates the characteristics of plasma distortion in wave-cutoff probe measurement and successfully restored the absolute value of electron density with varying probe tip gaps.

  2. NSTX Plasma Response to Lithium Coated Divertor

    SciTech Connect (OSTI)

    H.W. Kugel, M.G. Bell, J.P. Allain, R.E. Bell, S. Ding, S.P. Gerhardt, M.A. Jaworski, R. Kaita, J. Kallman, S.M. Kaye, B.P. LeBlanc, R. Maingi, R. Majeski, R. Maqueda, D.K. Mansfield, D. Mueller, R. Nygren, S.F. Paul, R. Raman, A.L. Roquemore, S.A. Sabbagh, H. Schneider, C.H. Skinner, V.A. Soukhanovskii, C.N. Taylor, J.R. Timberlak, W.R. Wampler, L.E. Zakharov, S.J. Zweben, and the NSTX Research Team

    2011-01-21

    NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, <0.1%. Initial results are reported from operation with a Liquid Lithium Divertor (LLD) recently installed.

  3. Characteristic of a triple-cathode vacuum arc plasma source

    SciTech Connect (OSTI)

    Xiang, W.; Li, M.; Chen, L.

    2012-02-15

    In order to generate a better ion beam, a triple-cathode vacuum arc plasma source has been developed. Three plasma generators in the vacuum arc plasma source are equally located on a circle. Each generator initiated by means of a high-voltage breakdown between the cathode and the anode could be operated separately or simultaneously. The arc plasma expands from the cathode spot region in vacuum. In order to study the behaviors of expanding plasma plume generated in the vacuum arc plasma source, a Langmuir probe array is employed to measure the saturated ion current of the vacuum arc plasma source. The time-dependence profiles of the saturated current density of the triple vacuum arc plasma source operated separately and simultaneously are given. Furthermore, the plasma characteristic of this vacuum arc plasma source is also presented in the paper.

  4. Shock compression of low-density foams

    SciTech Connect (OSTI)

    Holmes, N.C.

    1993-07-01

    Shock compression of very low density micro-cellular materials allows entirely new regimes of hot fluid states to be investigated experimentally. Using a two-stage light-gas gun to generate strong shocks, temperatures of several eV are readily achieved at densities of roughly 0.5--1 g/cm{sup 3} in large, uniform volumes. The conditions in these hot, expanded fluids are readily found using the Hugoniot jump conditions. We will briefly describe the basic methodology for sample preparation and experimental measurement of shock velocities. We present data for several materials over a range of initial densities. This paper will explore the applications of these methods for investigations of equations of state and phase diagrams, spectroscopy, and plasma physics. Finally, we discus the need for future work on these and related low-density materials.

  5. Characteristics of plasma properties in an ablative pulsed plasma thruster

    SciTech Connect (OSTI)

    Schoenherr, Tony; Nees, Frank; Arakawa, Yoshihiro; Komurasaki, Kimiya; Herdrich, Georg

    2013-03-15

    Pulsed plasma thrusters are electric space propulsion devices which create a highly transient plasma bulk in a short-time arc discharge that is expelled to create thrust. The transitional character and the dependency on the discharge properties are yet to be elucidated. In this study, optical emission spectroscopy and Mach-Zehnder interferometry are applied to investigate the plasma properties in variation of time, space, and discharge energy. Electron temperature, electron density, and Knudsen numbers are derived for the plasma bulk and discussed. Temperatures were found to be in the order of 1.7 to 3.1 eV, whereas electron densities showed maximum values of more than 10{sup 17} cm{sup -3}. Both values showed strong dependency on the discharge voltage and were typically higher closer to the electrodes. Capacitance and time showed less influence. Knudsen numbers were derived to be in the order of 10{sup -3}-10{sup -2}, thus, indicating a continuum flow behavior in the main plasma bulk.

  6. Solitary and shock waves in magnetized electron-positron plasma

    SciTech Connect (OSTI)

    Lu, Ding; Li, Zi-Liang; Abdukerim, Nuriman; Xie, Bai-Song

    2014-02-15

    An Ohm's law for electron-positron (EP) plasma is obtained. In the framework of EP magnetohydrodynamics, we investigate nonrelativistic nonlinear waves' solutions in a magnetized EP plasma. In the collisionless limit, quasistationary propagating solitary wave structures for the magnetic field and the plasma density are obtained. It is found that the wave amplitude increases with the Mach number and the Alfvén speed. However, the dependence on the plasma temperature is just the opposite. Moreover, for a cold EP plasma, the existence range of the solitary waves depends only on the Alfvén speed. For a hot EP plasma, the existence range depends on the Alfvén speed as well as the plasma temperature. In the presence of collision, the electromagnetic fields and the plasma density can appear as oscillatory shock structures because of the dissipation caused by the collisions. As the collision frequency increases, the oscillatory shock structure becomes more and more monotonic.

  7. One-dimensional time-dependent fluid model of a very high density

    Office of Scientific and Technical Information (OSTI)

    low-pressure inductively coupled plasma (Journal Article) | DOE PAGES One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma This content will become publicly available on December 28, 2016 Title: One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma A time-dependent two-fluid model has been developed to understand axial variations in the plasma parameters in a very high density (peak ne~

  8. Three-dimensional simulation of H-mode plasmas with localized...

    Office of Scientific and Technical Information (OSTI)

    Heslington, York YO10 5DD, United Kingdom Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA ITER Organization, Route de Vinon-sur-Verdon, CS 90046 - ...

  9. Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Photon Science Along with its primary missions-global security, energy security, basic science, and national competitiveness-the NIF & Photon Science Directorate also pursues research and development projects to innovate and develop cutting-edge technologies in support of those missions. This effort strategically invests in new technologies and development of large-scale photon systems for various federal agencies and industry sponsors. NIF&PS researchers are developing world-class

  10. Fermilab | Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    feature photo feature photo feature photo feature photo feature photo Science Navbar Toggle About Quick Info Science History Organization Photo and video gallery Diversity Education Safety Sustainability and environment Contact Newsroom Spotlight Press releases Fact sheets and brochures symmetry Interactions.org Photo and video archive Resources for ... Employees Researchers, Postdocs and Graduate Students Job Seekers Neighbors Industry K-12 Students, Teachers and Undergraduates Media Science

  11. Contacts - Plasma Couette Experiment - Cary Forest Group - UW Plasma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Contacts UW Madison Plasma Couette Experiment Contacts PCX HomeResearch MissionPhysics TopicsDeviceDiagnosticsContacts LinksPCX People CPLA Home Directory Publications Links University of Wisconsin Physics Department Department of Energy National Science Foundation Contacts Principal Investigator Cary B. Forest Graduate Student Cami Collins Engineers John Wallace Mike Clark Undergraduate Researchers Jonathan Jara-Almonte Kristine Garot

  12. Fire Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion ...

  13. Information Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Information Science and Technology (ASIS&T) American Society for Indexing (ASI) Digital Library Federation (DLF) National Archives and Records Administration (NARA) Special...

  14. SCIENCE Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Program early science program Early at the Argonne Leadership Computing Facility CONTACT Argonne Leadership Computing Facility | www.alcf.anl.gov | (877) 737-8615...

  15. Energy Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Scientists are advancing the fundamental science of materials within the context of global energy-related challenges. They are developing experimental and theoretical...

  16. Runaway electrons in a fully and partially ionized nonideal plasma

    SciTech Connect (OSTI)

    Ramazanov, T.S.; Turekhanova, K.M.

    2005-10-01

    This paper reports on a study of electron runaway for a nonideal plasma in an external electric field. Based on pseudopotential models of nonideal fully and partially ionized plasmas, the friction force was derived as a function of electron velocities. Dependences of the electron free path on plasma density and nonideality parameters were obtained. The impact of the relative number of runaway electrons on their velocity and temperature was considered for classical and semiclassical models of a nonideal plasma. It has been shown that for the defined intervals of the coupled plasma parameter, the difference between the relative numbers of runaway electron values is essential for various plasma models.

  17. News | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News Primary tabs View High Resolution(active tab) Princeton, Max Planck Society launch new research center for plasma physics Click on an image below to view the high resolution image. Then right click on the image and select "Save Image" or "Save Image As..." (From left to right) Princeton University Professor of Astrophysical Sciences James Stone, Princeton University President Shirley M. Tilghman, Princeton University Dean for Research A. J. Stewart Smith, Max Planck

  18. Plasma technology

    SciTech Connect (OSTI)

    Herlitz, H.G.

    1986-11-01

    This paper describes the uses of plasma technology for the thermal destruction of hazardous wastes such as PCBs, dioxins, hydrocarbons, military chemicals and biological materials; for metals recovery from steel making dusts. One advantage of the process is that destruction of wastes can be carried out on site. Systems in several countries use the excess thermal energy for district heating.

  19. News | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Top-5 Achievements at the Princeton Plasma Physics Laboratory in 2015 Click on an image below to view the high resolution image. Then right click on the image and select "Save Image" or "Save Image As..." From top left: 1.Magnetic island geometry revealing the mechanism for the density limit. (Reprinted with permission from Phys. Plasmas 22, 022514 2015); 2.Carlos Paz-Soldan and Raffi Nazikian advanced understanding of the control of heat bursts; 3.interior of the NSTX-U

  20. The Olympics of science knowledge at DOE's New Jersey Regional Science Bowl

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at PPPL | Princeton Plasma Physics Lab The Olympics of science knowledge at DOE's New Jersey Regional Science Bowl at PPPL By Jeanne Jackson DeVoe March 3, 2014 Tweet Widget Google Plus One Share on Facebook The J Droids, a science club in Warren, N.J., at the end of a long day of competing with the Science Bowl trophies in the foreground. They took home the largest of the trophies after winning the U.S. Department of Energy's New Jersey Regional Middle School Science Bowl on Feb. 21. (Photo

  1. The Olympics of science knowledge at PPPL's NJ Regional Science Bowl |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Princeton Plasma Physics Lab The Olympics of science knowledge at PPPL's NJ Regional Science Bowl By Jeanne Jackson DeVoe March 3, 2014 Tweet Widget Google Plus One Share on Facebook The J Droids, a science club in Warren, N.J., at the end of a long day of competing with the Science Bowl trophies in the foreground. They took home the largest of the trophies after winning the U.S. Department of Energy's New Jersey Regional Middle School Science Bowl on Feb. 21. (Photo by Elle Starkman/PPPL

  2. Picture of the Week: Plasma cubed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0 Plasma cubed Drawing on expertise from astrophysics, applied mathematics, fluid mechanics, data management, and computer science, a interdisciplinary multi-institution research team including Los Alamos scientists have discovered that turbulence may be key to solving the mystery of "fast magnetic reconnection" that has puzzled physicists for decades. August 3, 2015 Plasma cubed x Drawing on expertise from astrophysics, applied mathematics, fluid mechanics, data management, and

  3. Head, Engineering Department | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Head, Engineering Department Department: Engineering Supervisor(s): Deputy Director for Operations Staff: ENG 10 Requisition Number: 1600061 Position Summary: The Head of Engineering is responsible for planning and directing all engineering activities within the Princeton Plasma Physics Laboratory, and supporting the Laboratory mission by designing and operating world class fusion and plasma science experiments and engineering research. The successful candidate will be responsible for recruiting

  4. Fatima Ebrahimi | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fatima Ebrahimi Fatima Ebrahimi is the topical science group leader for theory/modeling of solenoid-free startup & ramp-up in NSTX-U. She has many years of experience in theoretical and global computational extended (magnetohydrodynamic) MHD with wide applications to astrophysical, laboratory and fusion plasmas. Studies of MHD stability in fusion plasmas, momentum transport, dynamo, and magnetic reconnection in fusion/laboratory and astrophysical plas- mas constitute her main research

  5. Hantao Ji | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hantao Ji Managing Principal Research Physicist Hantao Ji is a professor of Astrophysical Sciences at Princeton University and a Distinguished Research Fellow at PPPL. For more than 20 years he has been interested in the growing fields of plasma physics and astrophysics, and has dedicated his career to bringing them closer together. Interests Plasma astrophysics Magnetic reconnection Magnetorotational instability Dynamo effects and magnetic self-organization Free-surface liquid metal flows

  6. Outreach Efforts | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Outreach Efforts Excitement about plasmas and fusion comes alive when members of PPPL go out into the community or invite the public inside to sample the world of fusion research. The Laboratory has a variety of portable and at-home scientific demonstrations, laboratories and experiments that explain the beauty and wonder of science, fusion, and plasmas. The Laboratory hosts Open Houses and exhibits at local, regional, and national events such as Communiversity and the American Physical

  7. Nanotube array controlled carbon plasma deposition

    SciTech Connect (OSTI)

    Qian, Shi; Cao, Huiliang; Liu, Xuanyong; Ding, Chuanxian

    2013-06-17

    Finding approaches to control the elementary processes of plasma-solid interactions and direct the fluxes of matter at nano-scales becomes an important aspect in science. This letter reports that, by taking advantages of the spacing characteristics of discrete TiO{sub 2} nanotube arrays, the flying trajectories and the subsequent implantation and deposition manner of energetic carbon ions can be directed and controlled to fabricate hollow conical arrays. The study provides an alternative method for plasma nano-manufacturing.

  8. Effect of argon addition on plasma parameters and dust charging in hydrogen plasma

    SciTech Connect (OSTI)

    Kakati, B. Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.; Saxena, Y. C.

    2014-10-28

    Experimental results on effect of adding argon gas to hydrogen plasma in a multi-cusp dusty plasma device are reported. Addition of argon modifies plasma density, electron temperature, degree of hydrogen dissociation, dust current as well as dust charge. From the dust charging profile, it is observed that the dust current and dust charge decrease significantly up to 40% addition of argon flow rate in hydrogen plasma. But beyond 40% of argon flow rate, the changes in dust current and dust charge are insignificant. Results show that the addition of argon to hydrogen plasma in a dusty plasma device can be used as a tool to control the dust charging in a low pressure dusty plasma.

  9. A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma

    SciTech Connect (OSTI)

    Yang Min; Li Xiaoping; Xie Kai; Liu Donglin; Liu Yanming

    2013-01-15

    A large volume uniform plasma generator is proposed for the experiments of electromagnetic (EM) wave propagation in plasma, to reproduce a 'black out' phenomenon with long duration in an environment of the ordinary laboratory. The plasma generator achieves a controllable approximate uniform plasma in volume of 260 mm Multiplication-Sign 260 mm Multiplication-Sign 180 mm without the magnetic confinement. The plasma is produced by the glow discharge, and the special discharge structure is built to bring a steady approximate uniform plasma environment in the electromagnetic wave propagation path without any other barriers. In addition, the electron density and luminosity distributions of plasma under different discharge conditions were diagnosed and experimentally investigated. Both the electron density and the plasma uniformity are directly proportional to the input power and in roughly reverse proportion to the gas pressure in the chamber. Furthermore, the experiments of electromagnetic wave propagation in plasma are conducted in this plasma generator. Blackout phenomena at GPS signal are observed under this system and the measured attenuation curve is of reasonable agreement with the theoretical one, which suggests the effectiveness of the proposed method.

  10. Visualization of electronic density

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Grosso, Bastien; Cooper, Valentino R.; Pine, Polina; Hashibon, Adham; Yaish, Yuval; Adler, Joan

    2015-04-22

    An atom’s volume depends on its electronic density. Although this density can only be evaluated exactly for hydrogen-like atoms, there are many excellent numerical algorithms and packages to calculate it for other materials. 3D visualization of charge density is challenging, especially when several molecular/atomic levels are intertwined in space. We explore several approaches to 3D charge density visualization, including the extension of an anaglyphic stereo visualization application based on the AViz package to larger structures such as nanotubes. We will describe motivations and potential applications of these tools for answering interesting questions about nanotube properties.

  11. DIVERSITY. EDUCATION. SCIENCE. The ...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sciences-Biology, Computer, Information Technology, Geology, Mathematics, Microbiology, and Physics. Social Sciences-Economics, Organizational Psychology, Political Science, ...

  12. Flush-mounted probe diagnostics for argon glow discharge plasma

    SciTech Connect (OSTI)

    Xu, Liang Cao, Jinxiang; Liu, Yu; Wang, Jian; Du, Yinchang; Zheng, Zhe; Zhang, Xiao; Wang, Pi; Zhang, Jin; Li, Xiao; Qin, Yongqiang; Zhao, Liang

    2014-09-15

    A comparison is made between plasma parameters measured by a flush-mounted probe (FP) and a cylindrical probe (CP) in argon glow discharge plasma. Parameters compared include the space potential, the plasma density, and the effective electron temperature. It is found that the ion density determined by the FP agrees well with the electron density determined by the CP in the quasi-neutral plasma to better than 10%. Moreover, the space potential and effective electron temperature calculated from electron energy distribution function measured by the FP is consistent with that measured by the CP over the operated discharge current and pressure ranges. These results present the FP can be used as a reliable diagnostic tool in the stable laboratory plasma and also be anticipated to be applied in other complicated plasmas, such as tokamaks, the region of boundary-layer, and so on.

  13. NREL: Energy Sciences - Chemical and Materials Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the U.S. Department of Energy (DOE) National Photovoltaic Program and DOE Basic Energy Sciences Program. Materials Science. The Materials Science Group's research...

  14. National Security Science Archive

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science NSS Archive National Security Science Latest Issue:July 2015 past issues All Issues submit National Security Science Archive National Security Science magazine...

  15. Kando, M.; Esirkepov, T.Zh.; and others 70 PLASMA PHYSICS AND...

    Office of Scientific and Technical Information (OSTI)

    targets Pirozhkov, A.S.; Kando, M.; Esirkepov, T.Zh.; and others 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BEAM-PLASMA SYSTEMS; ELECTRON DENSITY; EV RANGE; HARMONIC GENERATION;...

  16. Density-dependent covariant energy density functionals

    SciTech Connect (OSTI)

    Lalazissis, G. A.

    2012-10-20

    Relativistic nuclear energy density functionals are applied to the description of a variety of nuclear structure phenomena at and away fromstability line. Isoscalar monopole, isovector dipole and isoscalar quadrupole giant resonances are calculated using fully self-consistent relativistic quasiparticle randomphase approximation, based on the relativistic Hartree-Bogoliubovmodel. The impact of pairing correlations on the fission barriers in heavy and superheavy nuclei is examined. The role of pion in constructing desnity functionals is also investigated.

  17. Secretary Steven Chu Visits Princeton Plasma Physics Laboratory...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    said has been at the center of the intellectual birth and coming of age of plasma and fusion science. Discussing our need for scientists to address our country's energy issues,...

  18. Distribution of Radiation Density in a Homogeneous Cloudy Laye

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Radiation Density in a Homogeneous Cloudy Layer S. V. Dvoryashin, K. A. Shukorov, A. H. Shukurov, and G. S. Golitsyn A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia The program block (Monte-Carlo method) allowing calculating radiation density in homogeneous and non-uniform clouds is developed for a homogeneous layer with various factors and phase functions of scattering the field of radiation density are calculated. On the basis of the calculated data

  19. Science on Saturday: Reimagining the Possible: Scientific Transformations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Shaping the Path Towards Fusion Energy | Princeton Plasma Physics Lab March 5, 2016, 9:30am Science On Saturday MBG Auditorium at PPPL Science on Saturday: Reimagining the Possible: Scientific Transformations Shaping the Path Towards Fusion Energy Dr. Edmund Synakowski Department of Energy, Office of Science Abstract: PDF icon Synakowski.pdf Science_on_Saturday05Mar2016_ESynakowski Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov Host(s): Dr. Andrew Zwicker

  20. Frontiers in Science Lectures focus on saving energy through

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    superconductivity Frontiers in Science Lectures Frontiers in Science Lectures focus on saving energy through superconductivity Dean Peterson discusses the science of high-temperature superconductivity in a series of Frontiers in Science lectures. June 12, 2009 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma

  1. FES Budget | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Budget Fusion Energy Sciences (FES) FES Home About Organization Chart .pdf file (80KB) Staff FES Budget FES Committees of Visitors Directions Jobs Fusion and Plasmas Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584 E: Email

  2. PPPL's science lecture debuts Jan. 10 with new name honoring long-time

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    organizer | Princeton Plasma Physics Lab PPPL's science lecture debuts Jan. 10 with new name honoring long-time organizer By Jeanne Jackson DeVoe December 22, 2014 Tweet Widget Google Plus One Share on Facebook The late Ron Hatcher hosted PPPL's Science on Saturday lectures. (Photo by Photo by Elle Starkman/ PPPL Office of Communications) The late Ron Hatcher hosted PPPL's Science on Saturday lectures. The U.S. Department of Energy's Princeton Plasma Laboratory's popular Science on Saturday

  3. Massachusetts Institute of Technology (MIT) | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Massachusetts Institute of Technology (MIT) Subscribe to RSS - Massachusetts Institute of Technology (MIT) Massachusetts Institute of Technology (MIT) Image: Massachusetts Institute of Technology (MIT) Applying physics, teamwork to fusion energy science Read more about Applying physics, teamwork to fusion energy science A Tour of Plasma Physics in Downtown Cambridge Read more about A Tour of Plasma Physics in Downtown Cambridge Placing Fusion Power on a Pedestal Read more about Placing Fusion

  4. DOE New Jersey Regional High School Science Bowl *NO LECTURE* | Princeton

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Physics Lab 1, 2015, 9:00am to 4:00pm Science Education Lab-wide DOE New Jersey Regional High School Science Bowl *NO LECTURE* Contact Information Coordinator(s): Deedee Ortiz-Arias, Science Education Department Program Administraor dortiz@ppl.gov Host(s): Dr. Andrew Zwicker, Science Education Department Head azwicker@pppl.gov

  5. Science Magazine

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & ANALYSIS www.sciencemag.org SCIENCE VOL 339 8 FEBRUARY 2013 635 Steven Chu, the fi rst Nobel-winning scien- tist to lead the sprawling U.S. Department of Energy (DOE), has rarely...

  6. Science Museum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nanotechnology and algae biofuels exhibits open July 26 at the Bradbury Science Museum July 22, 2013 LOS ALAMOS, N.M., July 22, 2013-Los Alamos National Laboratory's Bradbury Science Museum is opening two new exhibits July 26 as part of the Laboratory's 70th Anniversary celebration. One is a nanotechnology exhibit featuring the Laboratory's Center for Integrated Nanotechnologies (CINT) and the other is an algae biofuel exhibit from the Laboratory and the New Mexico Consortium. An opening

  7. Isotope Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science and Production 35 years of experience in isotope production, processing, and applications. Llllll Committed to the safe and reliable production of radioisotopes, products, and services. Contact: Kevin John LANL Isotope Program Manager kjohn@lanl.gov 505-667-3602 Sponsored by the Department of Energy National Isotope Program http://www.nuclear.energy.gov/isotopes/nelsotopes2a.html Isotopes for Environmental Science Isotopes produced at Los Alamos National Laboratory are used as

  8. Energy Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Science Energy Science Print Our current fossil-fuel-based system is causing potentially catastrophic changes to our planet. The quest for renewable, nonpolluting sources of energy requires us to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels. Light-source facilities-the synchrotrons of today and the next-generation light sources of tomorrow-are the scientific tools of choice for exploring the electronic and atomic structure

  9. Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Highlights Science Highlights Science highlights feature research conducted by staff and users at the ALS. If a Power Point summary slide or a PDF handout of the highlight is available, you will find it linked beneath the highlight listing and on the highlight's page. You may also print a version of a highlight by clicking the print icon associated with each highlight. Manganese Reduction-Oxidation Drives Plant Debris Decomposition Print Monday, 22 February 2016 00:00 ALS research has shown that

  10. Measurement Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wins 2016 Joseph F. Keithley Award for Advances in Measurement Science October 15, 2015 Honors to Albert Migliori, developer of resonant ultrasound spectroscopy LOS ALAMOS, N.M., Oct. 15, 2015-Los Alamos National Laboratory physicist Albert Migliori, having led the development of a powerful tool for important measurements in condensed matter physics including superconductivity, is being given the Joseph F. Keithley Award For Advances in Measurement Science, the top instrumentation prize of the

  11. Nuclear Science

    Energy Savers [EERE]

    and Engineering Education Sourcebook 2013 American Nuclear Society US Department of Energy Nuclear Science & Engineering Education Sourcebook 2013 North American Edition American Nuclear Society Education, Training, and Workforce Division US Department of Energy Office of Nuclear Energy Editor and Founder John Gilligan Professor of Nuclear Engineering North Carolina State University Version 5.13 Welcome to the 2013 Edition of the Nuclear Science and Engineering Education (NS&EE)

  12. What Makes Science, Science? Research, Shared Effort ... & A...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Makes Science, Science? Research, Shared Effort ... & A New Office of Science Website What Makes Science, Science? Research, Shared Effort ... & A New Office of Science Website ...

  13. Internal field, density & temperature measurements in MTF plasmas...

    Office of Scientific and Technical Information (OSTI)

    Have feedback or suggestions for a way to improve these results? Save Share this Record Citation Formats MLA APA Chicago Bibtex Export Metadata Endnote Excel CSV XML Save to My ...

  14. High Energy Density Laboratory Plasmas Program | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration Program | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional Testimony Fact Sheets Newsletters Press Releases Photo Gallery Jobs Apply for Our Jobs Our Jobs Working

  15. High Energy Density Laboratory Plasmas | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional Testimony Fact Sheets Newsletters Press Releases Photo Gallery Jobs Apply for Our Jobs Our Jobs Working at

  16. Multi-Scale Investigation of Sheared Flows In Magnetized Plasmas

    SciTech Connect (OSTI)

    Edward, Jr., Thomas

    2014-09-19

    Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

  17. Magneto-inertial Fusion: An Emerging Concept for Inertial Fusion and Dense Plasmas in Ultrahigh Magnetic Fields

    SciTech Connect (OSTI)

    Thio, Francis Y.C.

    2008-01-01

    An overview of the U.S. program in magneto-inertial fusion (MIF) is given in terms of its technical rationale, scientific goals, vision, research plans, needs, and the research facilities currently available in support of the program. Magneto-inertial fusion is an emerging concept for inertial fusion and a pathway to the study of dense plasmas in ultrahigh magnetic fields (magnetic fields in excess of 500 T). The presence of magnetic field in an inertial fusion target suppresses cross-field thermal transport and potentially could enable more attractive inertial fusion energy systems. A vigorous program in magnetized high energy density laboratory plasmas (HED-LP) addressing the scientific basis of magneto-inertial fusion has been initiated by the Office of Fusion Energy Sciences of the U.S. Department of Energy involving a number of universities, government laboratories and private institutions.

  18. Volumetric plasma source development and characterization.

    SciTech Connect (OSTI)

    Crain, Marlon D. (National Security Technologies, LLC, Las Vegas, NV); Maron, Yitzhak (Weizmann Institute of Science, Rehovot, Israel); Oliver, Bryan Velten; Starbird, Robert L. (National Security Technologies, LLC, Las Vegas, NV); Johnston, Mark D.; Hahn, Kelly Denise; Mehlhorn, Thomas Alan; Droemer, Darryl W. (National Security Technologies, LLC, Las Vegas, NV); National Security Technologies, LLC, Las Vegas, NV

    2008-09-01

    The development of plasma sources with densities and temperatures in the 10{sup 15}-10{sup 17} cm{sup -3} and 1-10eV ranges which are slowly varying over several hundreds of nanoseconds within several cubic centimeter volumes is of interest for applications such as intense electron beam focusing as part of the x-ray radiography program. In particular, theoretical work [1,2] suggests that replacing neutral gas in electron beam focusing cells with highly conductive, pre-ionized plasma increases the time-averaged e-beam intensity on target, resulting in brighter x-ray sources. This LDRD project was an attempt to generate such a plasma source from fine metal wires. A high voltage (20-60kV), high current (12-45kA) capacitive discharge was sent through a 100 {micro}m diameter aluminum wire forming a plasma. The plasma's expansion was measured in time and space using spectroscopic techniques. Lineshapes and intensities from various plasma species were used to determine electron and ion densities and temperatures. Electron densities from the mid-10{sup 15} to mid-10{sup 16} cm{sup -3} were generated with corresponding electron temperatures of between 1 and 10eV. These parameters were measured at distances of up to 1.85 cm from the wire surface at times in excess of 1 {micro}s from the initial wire breakdown event. In addition, a hydrocarbon plasma from surface contaminants on the wire was also measured. Control of these contaminants by judicious choice of wire material, size, and/or surface coating allows for the ability to generate plasmas with similar density and temperature to those given above, but with lower atomic masses.

  19. Meter Scale Plasma Source for Plasma Wakefield Experiments (Journal...

    Office of Scientific and Technical Information (OSTI)

    Meter Scale Plasma Source for Plasma Wakefield Experiments Citation Details In-Document Search Title: Meter Scale Plasma Source for Plasma Wakefield Experiments Authors:...

  20. University of Maryland component of the Center for Multiscale Plasma

    Office of Scientific and Technical Information (OSTI)

    Dynamics: Final Technical Report (Technical Report) | SciTech Connect SciTech Connect Search Results Technical Report: University of Maryland component of the Center for Multiscale Plasma Dynamics: Final Technical Report Citation Details In-Document Search Title: University of Maryland component of the Center for Multiscale Plasma Dynamics: Final Technical Report The Center for Multiscale Plasma Dynamics (CMPD) was a five-year Fusion Science Center. The University of Maryland (UMD) and UCLA

  1. Multinational achievement: PPPL collaborates on record fusion plasma in

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tokamak in China | Princeton Plasma Physics Lab Multinational achievement: PPPL collaborates on record fusion plasma in tokamak in China By John Greenwald November 25, 2013 Tweet Widget Google Plus One Share on Facebook Interior view of EAST tokamak (Photo by Institute of Plasma Physics, Chinese Academy of Sciences ) Interior view of EAST tokamak A multinational team led by Chinese researchers in collaboration with U.S. and European partners has successfully demonstrated a novel technique

  2. Multinational achievement: PPPL collaborates on record fusion plasma in

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tokamak in China | Princeton Plasma Physics Lab Multinational achievement: PPPL collaborates on record fusion plasma in tokamak in China By John Greenwald December 9, 2013 Tweet Widget Google Plus One Share on Facebook Interior view of EAST tokamak (Photo by Institute of Plasma Physics, Chinese Academy of Sciences ) Interior view of EAST tokamak A multinational team led by Chinese researchers in collaboration with U.S. and European partners has successfully demonstrated a novel technique for

  3. Adam Cohen becomes Deputy Under Secretary for Science and Energy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), Adam Cohen has been named Deputy Under Secretary for Science and Energy in Washington D.C....

  4. Spectroscopic Determination of the Magnetic Fields in Exploding Wire and X-pinch Plasmas

    SciTech Connect (OSTI)

    Hammer, David A.

    2013-12-19

    In this report, we summarize the progress that was made toward developing a new magnetic field diagnostic known as Zeeman Broadening for current carrying high energy density plasmas.

  5. Plasma wake field XUV radiation source

    DOE Patents [OSTI]

    Prono, Daniel S. (Los Alamos, NM); Jones, Michael E. (Los Alamos, NM)

    1997-01-01

    A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

  6. International science conferences in Santa Fe

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    International science conferences International science conferences in Santa Fe The conference are 2012 International Conference on Defects in Insulating Materials and Computer Simulation of Radiation Effects in Solids. June 22, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los

  7. Langmuir Probe Measurements in Plasma Shadows

    SciTech Connect (OSTI)

    Waldmann, O.; Koch, B.; Fussmann, G.

    2006-01-15

    When immersing a target into a plasma streaming along magnetic field lines, a distinct shadow region extending over large distances is observed by the naked eye downstream of the target.In this work we present an experimental study of the effect applying Langmuir probes. In contrast to expectations, there are only marginal changes in the profiles of temperature and density behind masks that cut away about 50% of the plasma cross-section. On the other hand, the mean density is drastically reduced by an order of magnitude. First attempts to simulate the observations by solving the classical 2D diffusion equation were not successful.

  8. One-dimensional time-dependent fluid model of a very high density

    Office of Scientific and Technical Information (OSTI)

    low-pressure inductively coupled plasma (Journal Article) | SciTech Connect One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma Citation Details In-Document Search This content will become publicly available on December 28, 2016 Title: One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma A time-dependent two-fluid model has been developed to understand axial variations in the plasma

  9. Nanodiamonds in dusty low-pressure plasmas

    SciTech Connect (OSTI)

    Vandenbulcke, L.; Gries, T.; Rouzaud, J. N.

    2009-01-26

    Dusty plasmas composed of carbon, hydrogen, and oxygen have been evidenced by optical emission spectroscopy and microwave interferometry, due to the increase in electron energy and the decrease in electron density. These plasmas allow homogeneous synthesis of nanodiamond grains composed of either pure diamond nanocrystals only (2-10 nm in size) or of diamond nanocrystals and some sp{sup 2}-hybridized carbon entities. The control of their size and their microstructure could open ways for a wide range of fields. Their formation from a plasma-activated gaseous phase is also attractive because the formation of nanodiamonds in the universe is still a matter of controversy.

  10. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1995-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  11. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, L.A.

    1995-11-14

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

  12. ECR apparatus with magnetic coil for plasma refractive index control

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1994-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  13. ECR apparatus with magnetic coil for plasma refractive index control

    DOE Patents [OSTI]

    Berry, L.A.

    1994-04-26

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figures.

  14. Reproducing continuous radio blackout using glow discharge plasma

    SciTech Connect (OSTI)

    Xie, Kai; Li, Xiaoping; Liu, Donglin; Shao, Mingxu [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China)] [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China); Zhang, Hanlu [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)] [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)

    2013-10-15

    A novel plasma generator is described that offers large-scale, continuous, non-magnetized plasma with a 30-cm-diameter hollow structure, which provides a path for an electromagnetic wave. The plasma is excited by a low-pressure glow discharge, with varying electron densities ranging from 10{sup 9} to 2.5 × 10{sup 11} cm{sup ?3}. An electromagnetic wave propagation experiment reproduced a continuous radio blackout in UHF-, L-, and S-bands. The results are consistent with theoretical expectations. The proposed method is suitable in simulating a plasma sheath, and in researching communications, navigation, electromagnetic mitigations, and antenna compensation in plasma sheaths.

  15. A Space-Charge-Neutralizing Plasma for Beam Drift Compression

    SciTech Connect (OSTI)

    Roy, P.K.; Seidl, P.A.; Anders, A.; Bieniosek, F.M.; Coleman, J.E.; Gilson, E.P.; Greenway, W.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Sefkow, A.B.; Waldron, W.L.; Welch, D.R.

    2008-08-01

    Simultaneous radial focusing and longitudinal compression of intense ion beams are being studied to heat matter to the warm dense matter, or strongly coupled plasma regime. Higher compression ratios can be achieved if the beam compression takes place in a plasma-filled drift region in which the space-charge forces of the ion beam are neutralized. Recently, a system of four cathodic arc plasma sources has been fabricated and the axial plasma density has been measured. A movable plasma probe array has been developed to measure the radial and axial plasma distribution inside and outside of a {approx} 10 cm long final focus solenoid (FFS). Measured data show that the plasma forms a thin column of diameter {approx} 5 mm along the solenoid axis when the FFS is powered with an 8T field. Measured plasma density of {ge} 1 x 10{sup 13} cm{sup -3} meets the challenge of n{sub p}/Zn{sub b} > 1, where n{sub p} and n{sub b} are the plasma and ion beam density, respectively, and Z is the mean ion charge state of the plasma ions.

  16. Plasma 101 | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma 101 10 Facts You Should Know About Plasma By Larry Bernard February 22, 2016 Tweet Widget Google Plus One Share on Facebook The Aurora Borealis (Northern Lights) (Photo by Philippe Moussette for Nasa.gov) The Aurora Borealis (Northern Lights) Gallery: NSTX interior NSTX interior W7-X plasma W7-X plasma The sun (Photo by nasa.gov) The sun It's the fourth state of matter: Solid, liquid, gas, and plasma. Plasma is a super-heated gas, so hot that its electrons get out of the atom's orbit and

  17. ?Linear Gas Jet with Tailored Density Profile"

    SciTech Connect (OSTI)

    KRISHNAN, Mahadevan

    2012-12-10

    Supersonic, highly collimated gas jets and gas-filled capillary discharge waveguides are two primary targets of choice for Laser Plasma Accelerators (LPA) . Present gas jets have lengths of only 2-4 mm at densities of 1-4E19 cm-3, sufficient for self trapping and electron acceleration to energies up to ~150 MeV. Capillary structures 3 cm long have been used to accelerate beams up to 1 GeV. Capillary discharges used in LPAs serve to guide the pump laser and optimize the energy gain. A wall-stabilized capillary discharge provides a transverse profile across the channel that helps guide the laser and combat diffraction. Gas injection via a fast nozzle at one end provides some longitudinal density control, to improve the coupling. Gas jets with uniform or controlled density profiles may be used to control electron bunch injection and are being integrated into capillary experiments to add tuning of density. The gas jet for electron injection has not yet been optimized. Our Ph-I results have provided the LPA community with an alternative path to realizing a 2-3GeV electron bunch using just a gas jet. For example, our slit/blade combination gives a 15-20mm long acceleration path with tunable density profile, serving as an alternative to a 20-mm long capillary discharge with gas injection at one end. In Ph-II, we will extend these results to longer nozzles, to see whether we can synthesize 30 or 40-mm long plasma channels for LPAs.

  18. Science Museum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Maintaining nuclear stability in times of transition focus of talk at Bradbury Science Museum January 9, 2014 First in series of evening lectures open to public LOS ALAMOS, N.M., Jan. 9, 2014-Los Alamos National Laboratory Senior Fellow Houston "Terry" Hawkins talks about the role that the nation's nuclear weapons stockpile plays in maintaining the nation's defense - and that of our allies - in a talk at 5:30 p.m., Jan. 15 at the Bradbury Science Museum. The talk is the first in a

  19. Science Museum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Emerging threats to global security focus of March 12 talk at Bradbury Science Museum March 6, 2014 Terry Wallace to address Lab's role in helping the government meet national security challenges LOS ALAMOS, N.M., March 6, 2014-Terry Wallace, principal associate director for Global Security at Los Alamos National Laboratory, will talk about potential emerging threats in a lecture at 5:30 p.m., March 12 at the Bradbury Science Museum. The talk is the third in a series of evening lectures planned

  20. Princeton University Plasma Physics Laboratory, Princeton, New Jersey. Annual report, October 1, 1990--September 30, 1991

    SciTech Connect (OSTI)

    Not Available

    1991-12-31

    This report discusses the following topics: Principal parameters of experimental devices; Tokamak Fusion Test Reactor; Burning Plasma Experiment; Princeton Beta Experiment-Modification; Current Drive Experiment-Upgrade; International Thermonuclear Experimental Reactor; International Collaboration; X-Ray Laser Studies; Hyperthermal Atomic Beam Source; Pure Electron Plasma Experiments; Plasma Processing: Deposition and Etching of Thin Films; Theoretical Studies; Tokamak Modeling; Engineering Department; Environment, Safety, and Health and Quality Assurance; Technology Transfer; Office of Human Resources and Administration; PPPL Patent Invention Disclosures; Office of Resource Management; Graduate Education: Plasma Physics; Graduate Education: Program in Plasma Science and Technology; and Science Education Program.

  1. Microsoft Word - Defense Science Quarterly 05-08.doc

    National Nuclear Security Administration (NNSA)

    Office of Defense Science May 2008 Defense Science Quarterly Inside This Issue 1 Message from the Director 2 Advanced Certification 3 Delivering High Energy Density Physics Data on the National Ignition Facility to Validate Predictive Physics Models 5 Texas Petawatt Laser Achieves Power Milestone 6 Sandia Light Gas Gun Tests Demonstrate the Ability to Deliver an Engineered Shock Wave Using a Graded-Density Thermal Spray Coating 7 Stewardship Science Academic Alliances Symposium Highlights 9

  2. Microsoft Word - Defense Science Quarterly 11-08 v2.doc

    National Nuclear Security Administration (NNSA)

    ... energy density physics experiments, molecular dynamics simulations of plasmas, ... have slowly transitioned from a base of design validation through nuclear testing to one ...

  3. Computer tomography of large dust clouds in complex plasmas

    SciTech Connect (OSTI)

    Killer, Carsten; Himpel, Michael; Melzer, André

    2014-10-15

    The dust density is a central parameter of a dusty plasma. Here, a tomography setup for the determination of the three-dimensionally resolved density distribution of spatially extended dust clouds is presented. The dust clouds consist of micron-sized particles confined in a radio frequency argon plasma, where they fill almost the entire discharge volume. First, a line-of-sight integrated dust density is obtained from extinction measurements, where the incident light from an LED panel is scattered and absorbed by the dust. Performing these extinction measurements from many different angles allows the reconstruction of the 3D dust density distribution, analogous to a computer tomography in medical applications.

  4. Ultra-High Intensity Magnetic Field Generation in Dense Plasma

    SciTech Connect (OSTI)

    Fisch, Nathaniel J

    2014-01-08

    I. Grant Objective The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereasthefficient generation of electric current in low-­?energy-­? density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­?energy-­? density plasma the ideas for steady-­?state current drive developed for low-­?energy-­? density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­?energy-­?density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.

  5. TM01-mode microwave propagation property analysis for plasmas...

    Office of Scientific and Technical Information (OSTI)

    ... This comes from a reason that a larger electron density in the surface-wave plasma absorbs a larger quantity of the microwave power. From the above comparisons between results ...

  6. Better Fusion Plasma Operating Scenarios are Being Explored and Extended on

    Office of Science (SC) Website

    the Alcator C-Mod Tokamak | U.S. DOE Office of Science (SC) Better Fusion Plasma Operating Scenarios are Being Explored and Extended on the Alcator C-Mod Tokamak Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585

  7. New Theoretical Model of the Complex Edge Region of Fusion Plasmas Proves

    Office of Science (SC) Website

    Accurate | U.S. DOE Office of Science (SC) New Theoretical Model of the Complex Edge Region of Fusion Plasmas Proves Accurate Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584

  8. Large Plasma Flow Discovered in the Helically Symmetric Experiment | U.S.

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DOE Office of Science (SC) Large Plasma Flow Discovered in the Helically Symmetric Experiment Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584 E: Email Us More Information »

  9. Radio frequency discharge with control of plasma potential distribution

    SciTech Connect (OSTI)

    Dudnikov, Vadim; Dudnikov, A.

    2012-02-15

    A RF discharge plasma generator with additional electrodes for independent control of plasma potential distribution is proposed. With positive biasing of this ring electrode relative end flanges and longitudinal magnetic field a confinement of fast electrons in the discharge will be improved for reliable triggering of pulsed RF discharge at low gas density and rate of ion generation will be enhanced. In the proposed discharge combination, the electron energy is enhanced by RF field and the fast electron confinement is improved by enhanced positive plasma potential which improves the efficiency of plasma generation significantly. This combination creates a synergetic effect with a significantly improving the plasma generation performance at low gas density. The discharge parameters can be optimized for enhance plasma generation with acceptable electrode sputtering.

  10. Plasma physics | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    physics Subscribe to RSS - Plasma physics The study of plasma, a partially-ionized gas that is electrically conductive and able to be confined within a magnetic field, and how it ...

  11. Plasma astrophysics | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Subscribe to RSS - Plasma astrophysics A field of physics that is growing in interest ... McComas named vice president for the Princeton Plasma Physics Laboratory David McComas, an ...

  12. Information Science, Computing, Applied Math

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Capabilities Information Science, Computing, Applied Math science-innovationassetsimagesicon-science.jpg Information Science, Computing, Applied Math National security ...

  13. Impact of anomalous dispersion on the interferometer measurements of plasmas

    SciTech Connect (OSTI)

    Nilsen, J; Johnson, W R; Iglesias, C A; Scofield, J H

    2004-12-16

    For many decades optical interferometers have been used to measure the electron density of plasmas. During the last ten years X-ray lasers in the wavelength range 14 to 47 nm have enabled researchers to use interferometers to probe even higher density plasmas. The data analysis assumes that the index of refraction is due only to the free electrons, which makes the index of refraction less than one and the electron density proportional to the number of fringe shifts. Recent experiments in Al plasmas observed plasmas with an index of refraction greater than one and made us question the validity of the usual formula for calculating the index of refraction. Recent calculations showed how the anomalous dispersion from the bound electrons can dominate the index of refraction in many types of plasma and make the index greater than one or enhance the index such that one would greatly overestimate the electron density of the plasma using interferometers. In this work we calculate the index of refraction of C, Al, Ti, and Pd plasmas for photon energies from 0 to 100 eV (12.4 nm) using a new average-atom code. The results show large variations from the free electron approximation under many different plasma conditions. We validate the average-atom code against the more detailed OPAL code for carbon and aluminum plasmas. During the next decade X-ray free electron lasers and other sources will be available to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

  14. Density Equalizing Map Projections

    Energy Science and Technology Software Center (OSTI)

    1995-07-01

    A geographic map is mathematically transformed so that the subareas of the map are proportional to a given quantity such as population. In other words, population density is equalized over the entire map. The transformed map can be used as a display tool, or it can be statistically analyzed. For example, cases of disease plotted on the transformed map should be uniformly distributed at random, if disease rates are everywhere equal. Geographic clusters of diseasemore »can be readily identified, and their statistical significance determined, on a density equalized map.« less

  15. Plasma research shows promise for future compact accelerators

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma research shows promise for future compact accelerators Plasma research shows promise for future compact accelerators A transformative breakthrough in controlling ion beams allows small-scale laser-plasma accelerators to deliver unprecedented power densities. December 21, 2015 The team in front of the Trident Target Chamber. Back, from left: Tom Shimada, Sha-Marie Reid, Adam Sefkow, Miguel Santiago, and Chris Hamilton. Front, from left: Russ Mortensen, Chengkun Huang, Sasi Palaniyappan,

  16. Ion Beam Neutralization by a Tenuous Background Plasma ---- Inventors Igor

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Kaganovich and William Berdanier | Princeton Plasma Physics Lab Ion Beam Neutralization by a Tenuous Background Plasma ---- Inventors Igor Kaganovich and William Berdanier The neutralization and focusing of intense charged particle beam pulses by electrons form the basis for a wide range of applications for accelerators, heavy ion fusion, and astrophysics. This invention shows that for intense ion beam pulses, a background plasma with a low relative density can be used to effectively

  17. Optical Spectroscopic Diagnostics Of Dusty Plasma In RF Discharge

    SciTech Connect (OSTI)

    Orazbayev, S. A.; Jumagulov, M. N.; Dosbolayev, M. K.; Silamiya, M.; Ramazanov, T. S.; Boufendi, L.

    2011-11-29

    The parameters of the buffer plasma containing dust particles were measured by means of spectroscopic methods. The change in the emission spectrum of the buffer plasma with addition of dust was observed. It seems to relate to changing in temperature and number density of electrons due to the influence of dusts.

  18. Interparticle interaction and transport processes in dense semiclassical plasmas

    SciTech Connect (OSTI)

    Baimbetov, F.B.; Giniyatova, Sh.G.

    2005-04-15

    On the basis of the density response formalism an expression for the pseudopotential of dense semiclassical plasma, which takes account of quantum-mechanical effects, local field corrections, and electronic screening effects is obtained. The static structure factors taking into account both local fields and quantum-mechanical effects are calculated. An electrical conductivity, thermal conductivity, and viscosity of dense semiclassical plasma are studied.

  19. Top Science of 2013

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    RAPTOR telescope witnesses black hole birth science-innovationassetsimagesicon-science.jpg Top Science of 2013 Our strong interdisciplinary teaming and unique research...

  20. Top Science of 2013

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Liquid-scanning technology boosts airport security science-innovationassetsimagesicon-science.jpg Top Science of 2013 Our strong interdisciplinary teaming and unique research...

  1. National Security Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science National Security Science Latest Issue:July 2015 past issues All Issues submit National Security Science Showcasing Los Alamos National Laboratory's work on nuclear...

  2. ARM - Key Science Questions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govScienceKey Science Questions Science Research Themes Research Highlights Journal Articles Collaborations Atmospheric System Research (ASR) Earth System Modeling Regional &...

  3. Top Science of 2013

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Roadrunner firsts pave way for greener, faster supercomputing science-innovationassetsimagesicon-science.jpg Top Science of 2013 Our strong interdisciplinary teaming and ...

  4. Nuclear Science & Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nuclear Science & Technology Nuclear Science & Technology1354608000000Nuclear Science & TechnologySome of these resources are LANL-only and will require Remote Access. No...

  5. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, T.W.

    1994-09-06

    A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

  6. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, Terry W. (Tracy, CA)

    1994-01-01

    A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

  7. Global coherence of dust density waves

    SciTech Connect (OSTI)

    Killer, Carsten; Melzer, André

    2014-06-15

    The coherence of self-excited three-dimensional dust density waves has been experimentally investigated by comparing global and local wave properties. For that purpose, three-dimensional dust clouds have been confined in a radio frequency plasma with thermophoretic levitation. Global wave properties have been measured from the line-of-sight integrated dust density obtained from homogenous light extinction measurements. Local wave properties have been obtained from thin, two-dimensional illuminated laser slices of the cloud. By correlating the simultaneous global and local wave properties, the spatial coherence of the waves has been determined. We find that linear waves with small amplitudes tend to be fragmented, featuring an incoherent wave field. Strongly non-linear waves with large amplitudes, however, feature a strong spatial coherence throughout the dust cloud, indicating a high level of synchronization.

  8. Plasma parameters and electron energy distribution functions in a magnetically focused plasma

    SciTech Connect (OSTI)

    Samuell, C. M.; Blackwell, B. D.; Howard, J.; Corr, C. S. [Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra (Australia)

    2013-03-15

    Spatially resolved measurements of ion density, electron temperature, floating potential, and the electron energy distribution function (EEDF) are presented for a magnetically focused plasma. The measurements identify a central plasma column displaying Maxwellian EEDFs at an electron temperature of about 5 eV indicating the presence of a significant fraction of electrons in the inelastic energy range (energies above 15 eV). It is observed that the EEDF remains Maxwellian along the axis of the discharge with an increase in density, at constant electron temperature, observed in the region of highest magnetic field strength. Both electron density and temperature decrease at the plasma radial edge. Electron temperature isotherms measured in the downstream region are found to coincide with the magnetic field lines.

  9. Density gradient effects on transverse shear driven lower hybrid waves

    SciTech Connect (OSTI)

    DuBois, Ami M.; Thomas, Edward; Amatucci, William E.; Ganguli, Gurudas

    2014-06-15

    Shear driven instabilities are commonly observed in the near-Earth space, particularly in boundary layer plasmas. When the shear scale length (L{sub E}) is much less than the ion gyro-radius (?{sub i}) but greater than the electron gyro-radius (?{sub e}), the electrons are magnetized in the shear layer, but the ions are effectively un-magnetized. The resulting shear driven instability, the electron-ion hybrid (EIH) instability, is investigated in a new interpenetrating plasma configuration in the Auburn Linear EXperiment for Instability Studies. In order to understand the dynamics of magnetospheric boundary layers, the EIH instability is studied in the presence of a density gradient located at the boundary layer between two plasmas. This paper reports on a recent experiment in which electrostatic lower hybrid waves are identified as the EIH instability, and the effect of a density gradient on the instability properties are investigated.

  10. Is sustainability science really a science?

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Is sustainability science really a science? Is sustainability science really a science? The team's work shows that although sustainability science has been growing explosively since the late 1980s, only in the last decade has the field matured into a cohesive area of science. November 22, 2011 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience,

  11. Inductively generated streaming plasma ion source

    DOE Patents [OSTI]

    Glidden, Steven C.; Sanders, Howard D.; Greenly, John B.

    2006-07-25

    A novel pulsed, neutralized ion beam source is provided. The source uses pulsed inductive breakdown of neutral gas, and magnetic acceleration and control of the resulting plasma, to form a beam. The beam supplies ions for applications requiring excellent control of ion species, low remittance, high current density, and spatial uniformity.

  12. Energy Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Science Print Our current fossil-fuel-based system is causing potentially catastrophic changes to our planet. The quest for renewable, nonpolluting sources of energy requires us to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels. Light-source facilities-the synchrotrons of today and the next-generation light sources of tomorrow-are the scientific tools of choice for exploring the electronic and atomic structure of matter. As

  13. Fire Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear Energy

  14. Chemical Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemical Sciences - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced

  15. Computational Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear Energy

  16. Discovery Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Discovery Science Since the beginning of civilization, humans have marveled at the night sky and pondered the vast stretches of the universe. The invention of telescopes in the 17th century revealed the first details of the Moon and the planets in our solar system. Four hundred years later, space-based observatories such as NASA's Hubble and Kepler regularly capture amazing vistas of billions of galaxies millions of light years away. Despite these advances, astronomers have only been able to

  17. Information Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 Information Sciences Uncovering actionable knowledge and generating insight into exascale datasets from heterogeneous sources in real time Leadership Group Leader Patrick M. Kelly Email Deputy Group Leader Amy Larson Email Contact Us Administrator Yvonne McKelvey Email Conceptual illustration of futuristic data stream processing. Developing methods and tools for understanding complex interactions and extracting actionable information from massive data streams. Basic and applied research

  18. Stewardship Science Academic Alliances Program | National Nuclear Security

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Administration Stewardship Science Academic Alliances (SSAA) Program Overview Established in 2002, the Stewardship Science Academic Alliances Program funds academic research in the areas of materials under extreme conditions, low energy nuclear science, radiochemistry, and high energy density physics. One of the goals of the program is to fund research projects at universities that conduct fundamental science and technology research that is of relevance to stockpile stewardship. An important

  19. Density Log | Open Energy Information

    Open Energy Info (EERE)

    Density Log Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Density Log Details Activities (7) Areas (6) Regions (0) NEPA(0) Exploration...

  20. Rock Density | Open Energy Information

    Open Energy Info (EERE)

    Density Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Density Details Activities (2) Areas (2) Regions (0) NEPA(0) Exploration Technique...

  1. Three regimes of relativistic beam - plasma interaction

    SciTech Connect (OSTI)

    Muggli, P.; Allen, B.; Fang, Y.; Yakimenko, V.; Babzien, M.; Kusche, K.; Fedurin, M.; Vieira, J.; Martins, J.; Silva, L.

    2012-12-21

    Three regimes of relativistic beam - plasma interaction can in principle be reached at the ATF depending on the relative transverse and longitudinal size of the electron bunch when compared to the cold plasma collisionless skin depth c?{omega}{sub pe}: the plasma wakefield accelerator (PWFA), the self-modulation instability (SMI), and the current filamentation instability (CFI) regime. In addition, by choosing the bunch density, the linear, quasi-nonlinear and non linear regime of the PWFA can be reached. In the case of the two instabilities, the bunch density determines the growth rate and therefore the occurrence or not of the instability. We briefly describe these three regimes and outline results demonstrating that all these regime have or will be reached experimentally. We also outline planned and possible follow-on experiments.

  2. Numerical Studies of Impurities in Fusion Plasmas

    DOE R&D Accomplishments [OSTI]

    Hulse, R. A.

    1982-09-01

    The coupled partial differential equations used to describe the behavior of impurity ions in magnetically confined controlled fusion plasmas require numerical solution for cases of practical interest. Computer codes developed for impurity modeling at the Princeton Plasma Physics Laboratory are used as examples of the types of codes employed for this purpose. These codes solve for the impurity ionization state densities and associated radiation rates using atomic physics appropriate for these low-density, high-temperature plasmas. The simpler codes solve local equations in zero spatial dimensions while more complex cases require codes which explicitly include transport of the impurity ions simultaneously with the atomic processes of ionization and recombination. Typical applications are discussed and computational results are presented for selected cases of interest.

  3. Science DMZ Implemented at NERSC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NERSC Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ @ UF Science DMZ @...

  4. Science on Saturday: Brutal Efficiency: How Mating and Reproduction

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Influence C. Elegans Longevity | Princeton Plasma Physics Lab 7, 2016, 9:30am Science On Saturday MBG Auditorium, PPPL Science on Saturday: Brutal Efficiency: How Mating and Reproduction Influence C. Elegans Longevity Professor Coleen Murphy Princeton University Abstract: PDF icon 07 Murphy.pdf Science_on_Saturday27Feb2016_CMurphy Contact Information Coordinator(s): Ms. Deedee Ortiz-Arias dortiz@pppl.gov Host(s): Dr. Andrew Zwicker azwicker@pppl.gov PPPL Entrance Procedures Visitor

  5. DOE Office of Science Computing Facility Operational Assessment Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Computing Facility Operational Assessment Program Stephane Ethier Princeton Plasma Physics Lab NUG Meeting, 17 Sep 2007 Objective * The DOE Office of Science is required to conduct an Operational Assessment (OA) Review of the efficiencies in the steady-state operations of each of the DOE Office of Science High Performance Computing (HPC) Facilities. * OMB requirement for capital planning once an asset is procured and operational * Focuses on the measurement of customer results, business

  6. Christina Behr-Andres named science advisor to governor

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science advisor to governor Christina Behr-Andres named science advisor to governor Behr-Andres will aid indevelopment and promotion of science and technology policies for economic and educational opportunities. June 9, 2011 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos

  7. Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

    SciTech Connect (OSTI)

    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.

  8. Plasma sweeper. [Patents

    DOE Patents [OSTI]

    Motley, R.W.; Glanz, J.

    1982-10-25

    A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

  9. Preface: Special Topic on Advances in Density Functional Theory

    SciTech Connect (OSTI)

    Yang, Weitao

    2014-05-14

    This Special Topic Issue on the Advances in Density Functional Theory, published as a celebration of the fifty years of density functional theory, contains a retrospective article, a perspective article, and a collection of original research articles that showcase recent theoretical advances in the field. It provides a timely discussion reflecting a cross section of our understanding, and the theoretical and computational developments, which have significant implications in broad areas of sciences and engineering.

  10. Negative plasma potential in a multidipole chamber with a dielectric coated plasma boundary

    SciTech Connect (OSTI)

    Sheehan, J. P.; Hershkowitz, Noah

    2012-05-15

    Negative plasma potentials with respect to a grounded wall that was coated with a dielectric have been achieved in an electropositive plasma confined by a multidipole device. A Langmuir probe was used to measure the density and temperatures of the bi-Maxwellian distribution electrons and an emissive probe was used to measure the plasma potential profile near the plasma boundary. For many discharge parameters, the potential profile was that of a typical electropositive sheath, but it was shifted negative due to negative charge accumulated on the plasma-surface boundary. A virtual cathode was observed near the boundary when the neutral pressure, primary electron energy, and/or discharge current were low ({approx}2 x 10{sup -4} Torr, {approx}60 eV, and 80 mA, respectively). The behavior of the sheath potential was shown to be consistent with that predicted by particle balance and a qualitative mechanism for wall charging is presented.

  11. The density gradient effect on quantum Weibel instability

    SciTech Connect (OSTI)

    Mahdavi, M. Khodadadi Azadboni, F.

    2015-03-15

    The Weibel instability plays an important role in stopping the hot electrons and energy deposition mechanism in the fast ignition of inertial fusion process. In this paper, the effects of the density gradient and degeneracy on Weibel instability growth rate are investigated. Calculations show that decreasing the density degenerate in the plasma corona, near the relativistic electron beam emitting region by 8.5% leads to a 92% reduction in the degeneracy parameter and about 90% reduction in Weibel instability growth rate. Also, decreasing the degenerate density near the fuel core by 8.5% leads to 1% reduction in the degeneracy parameter and about 8.5% reduction in Weibel instability growth rate. The Weibel instability growth rate shrinks to zero and the deposition condition of relativistic electron beam energy can be shifted to the fuel core for a suitable ignition by increasing the degeneracy parameter in the first layer of plasma corona.

  12. Science Brief Submission Form

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Brief Submission Form Science Brief Submission Form Print Tuesday, 01 May 2007 00:00 Loading... < Prev

  13. Science and Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation /science-innovation/_assets/images/icon-science.jpg Science and Innovation Our strong interdisciplinary teaming and unique research facilities allow us to develop solutions to complex problems, and to support partners and collaborators, all with the goal of strengthening national security and making a safer world. Science & Engineering Capabilities» Science Programs» Science Facilities» Features» Capabilities Strategy: Science Pillars» Top Ten Innovations of 2013 Science and

  14. Life sciences and environmental sciences

    SciTech Connect (OSTI)

    Not Available

    1992-02-01

    The DOE laboratories play a unique role in bringing multidisciplinary talents -- in biology, physics, chemistry, computer sciences, and engineering -- to bear on major problems in the life and environmental sciences. Specifically, the laboratories utilize these talents to fulfill OHER's mission of exploring and mitigating the health and environmental effects of energy use, and of developing health and medical applications of nuclear energy-related phenomena. At Lawrence Berkeley Laboratory (LBL) support of this mission is evident across the spectrum of OHER-sponsored research, especially in the broad areas of genomics, structural biology, basic cell and molecular biology, carcinogenesis, energy and environment, applications to biotechnology, and molecular, nuclear and radiation medicine. These research areas are briefly described.

  15. Life sciences and environmental sciences

    SciTech Connect (OSTI)

    Not Available

    1992-02-01

    The DOE laboratories play a unique role in bringing multidisciplinary talents -- in biology, physics, chemistry, computer sciences, and engineering -- to bear on major problems in the life and environmental sciences. Specifically, the laboratories utilize these talents to fulfill OHER`s mission of exploring and mitigating the health and environmental effects of energy use, and of developing health and medical applications of nuclear energy-related phenomena. At Lawrence Berkeley Laboratory (LBL) support of this mission is evident across the spectrum of OHER-sponsored research, especially in the broad areas of genomics, structural biology, basic cell and molecular biology, carcinogenesis, energy and environment, applications to biotechnology, and molecular, nuclear and radiation medicine. These research areas are briefly described.

  16. Study on the effect of target on plasma parameters of magnetron sputtering discharge plasma

    SciTech Connect (OSTI)

    Saikia, P.; Kakati, B.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur-782 402, Kamrup, Assam (India)] [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur-782 402, Kamrup, Assam (India)

    2013-10-15

    In this study, the effect of magnetron target on different plasma parameters of Argon/Hydrogen (Ar - H{sub 2}) direct current (DC) magnetron discharge is examined. Here, Copper (Cu) and Chromium (Cr) are used as magnetron targets. The value of plasma parameters such as electron temperature (kT{sub e}), electron density (N{sub e}), ion density (N{sub i}), degree of ionization of Ar, and degree of dissociation of H{sub 2} for both the target are studied as a function of input power and hydrogen content in the discharge. The plasma parameters are determined by using Langmuir probe and Optical emission spectroscopy. On the basis of the different reactions in the gas phase, the variation of plasma parameters and sputtering rate are explained. The obtained results show that electron and ion density decline with gradual addition of Hydrogen in the discharge and increase with rising input power. It brings significant changes on the degree of ionization of Ar and dissociation of H{sub 2}. The enhanced value of electron density (N{sub e}), ion density (N{sub i}), degree of Ionization of Ar, and degree of dissociation of H{sub 2} for Cr compared to Cu target is explained on the basis of it's higher Ion Induced Secondary Electron Emission Coefficient (ISEE) value.

  17. Shapes of Spectral Lines of Nonuniform Plasma of Electric Arc Discharge Between Copper Electrodes

    SciTech Connect (OSTI)

    Babich, Ida L.; Boretskij, Viacheslav F.; Veklich, Anatoly N.

    2007-09-28

    The radial profiles of the temperature and electron density in the plasma of the free burning electric arc between copper electrodes are studied by optical spectroscopy techniques. The electron density and the temperature in plasma as initial parameters were used in the calculation of the plasma composition in local thermodynamic equilibrium (LTE) assumption. We used the Saha's equation for copper, nitrogen and oxygen, dissociation equation for nitrogen and oxygen, the equation of plasma electrical neutrality and Dalton's law as well. So, it would be possible to determine the amounts of metal vapours in plasma.

  18. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect (OSTI)

    Myra, J. R.

    2014-02-15

    Radio frequency waves for heating and current drive of plasmas in tokamaks and other magnetic confinement devices must first traverse the scrape-off-layer (SOL) before they can be put to their intended use. The SOL plasma is strongly turbulent and intermittent in space and time. These turbulent properties of the SOL, which are not routinely taken into account in wave propagation codes, can have an important effect on the coupling of waves through an evanescent SOL or edge plasma region. The effective scale length for fast wave (FW) evanescence in the presence of short-scale field-aligned filamentary plasma turbulence is addressed in this paper. It is shown that although the FW wavelength or evanescent scale length is long compared with the dimensions of the turbulence, the FW does not simply average over the turbulent density; rather, the average is over the exponentiation rate. Implications for practical situations are discussed.

  19. Gedanken densities and exact constraints in density functional theory

    SciTech Connect (OSTI)

    Perdew, John P.; Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122 ; Ruzsinszky, Adrienn; Sun, Jianwei; Burke, Kieron

    2014-05-14

    Approximations to the exact density functional for the exchange-correlation energy of a many-electron ground state can be constructed by satisfying constraints that are universal, i.e., valid for all electron densities. Gedanken densities are designed for the purpose of this construction, but need not be realistic. The uniform electron gas is an old gedanken density. Here, we propose a spherical two-electron gedanken density in which the dimensionless density gradient can be an arbitrary positive constant wherever the density is non-zero. The Lieb-Oxford lower bound on the exchange energy can be satisfied within a generalized gradient approximation (GGA) by bounding its enhancement factor or simplest GGA exchange-energy density. This enhancement-factor bound is well known to be sufficient, but our gedanken density shows that it is also necessary. The conventional exact exchange-energy density satisfies no such local bound, but energy densities are not unique, and the simplest GGA exchange-energy density is not an approximation to it. We further derive a strongly and optimally tightened bound on the exchange enhancement factor of a two-electron density, which is satisfied by the local density approximation but is violated by all published GGA's or meta-GGA’s. Finally, some consequences of the non-uniform density-scaling behavior for the asymptotics of the exchange enhancement factor of a GGA or meta-GGA are given.

  20. Science Cafe

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cafés Science Cafe April 27, 2015-Special ALS Colloquium Print Wednesday, 22 April 2015 13:19 Special Event on Monday, April 27 @ 12 noon, USB 15-253 X-Ray Microscopy: The First 120 Years Janos Kirz, ALS Abstract Röntgen's great discovery became an instant public sensation. Fascination with the "new kind of rays" that could reveal the structure of opaque objects swept the world in 1896. Fifty years later it was widely recognized that the short wavelength of the radiation should open

  1. Effect of plasma parameters on growth and field emission properties of spherical carbon nanotube tip

    SciTech Connect (OSTI)

    Sharma, Suresh C.; Tewari, Aarti

    2011-06-15

    The effect of plasma parameters (e.g., electron density and temperature, ion density and temperature, neutral atom density and temperature) on the growth (without a catalyst), structure, and field emission properties of a spherical carbon nanotube (CNT) tip has been theoretically investigated. A theoretical model of charge neutrality, including the kinetics of electrons, positively charged ions, and neutral atoms and the energy balance of the various species in plasma, has been developed. Numerical calculations of the radius of the spherical CNT tip for different CNT number densities and plasma parameters have been carried out for the typical glow discharge plasma parameters. It is found that upon an increase in the CNT number density and plasma parameters, the radius of the spherical CNT tip decreases, and consequently the field emission factor for the spherical CNT tip increases.

  2. Large area atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S. (Los Alamos, NM); Henins, Ivars (Los Alamos, NM); Babayan, Steve E. (Huntington Beach, CA); Hicks, Robert F. (Los Angeles, CA)

    2001-01-01

    Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.

  3. Cold atmospheric plasma in cancer therapy

    SciTech Connect (OSTI)

    Keidar, Michael; Shashurin, Alex; Volotskova, Olga; Ann Stepp, Mary; Srinivasan, Priya; Sandler, Anthony; Trink, Barry

    2013-05-15

    Recent progress in atmospheric plasmas has led to the creation of cold plasmas with ion temperature close to room temperature. This paper outlines recent progress in understanding of cold plasma physics as well as application of cold atmospheric plasma (CAP) in cancer therapy. Varieties of novel plasma diagnostic techniques were developed recently in a quest to understand physics of CAP. It was established that the streamer head charge is about 10{sup 8} electrons, the electrical field in the head vicinity is about 10{sup 7} V/m, and the electron density of the streamer column is about 10{sup 19} m{sup ?3}. Both in-vitro and in-vivo studies of CAP action on cancer were performed. It was shown that the cold plasma application selectively eradicates cancer cells in-vitro without damaging normal cells and significantly reduces tumor size in-vivo. Studies indicate that the mechanism of action of cold plasma on cancer cells is related to generation of reactive oxygen species with possible induction of the apoptosis pathway. It is also shown that the cancer cells are more susceptible to the effects of CAP because a greater percentage of cells are in the S phase of the cell cycle.

  4. Influence of electron injection into 27 cm audio plasma cell on the plasma diagnostics

    SciTech Connect (OSTI)

    Haleem, N. A.; Ragheb, M. S.; Zakhary, S. G.; El Fiki, S. A.; Nouh, S. A.; El Disoki, T. M.

    2013-08-15

    In this article, the plasma is created in a Pyrex tube (L = 27 cm, ?= 4 cm) as a single cell, by a capacitive audio frequency (AF) discharge (f = 10–100 kHz), at a definite pressure of ?0.2 Torr. A couple of tube linear and deviating arrangements show plasma characteristic conformity. The applied AF plasma and the injection of electrons into two gas mediums Ar and N{sub 2} revealed the increase of electron density at distinct tube regions by one order to attain 10{sup 13}/cm{sup 3}. The electrons temperature and density strengths are in contrast to each other. While their distributions differ along the plasma tube length, they show a decaying sinusoidal shape where their peaks position varies by the gas type. The electrons injection moderates electron temperature and expands their density. The later highest peak holds for the N{sub 2} gas, at electrons injection it changes to hold for the Ar. The sinusoidal decaying density behavior generates electric fields depending on the gas used and independent of tube geometry. The effect of the injected electrons performs a responsive impact on electrons density not attributed to the gas discharge. Analytical tools investigate the interaction of the plasma, the discharge current, and the gas used on the electrodes. It points to the emigration of atoms from each one but for greater majority they behave to a preferred direction. Meanwhile, only in the linear regime, small percentage of atoms still moves in reverse direction. Traces of gas atoms revealed on both electrodes due to sheath regions denote lack of their participation in the discharge current. In addition, atoms travel from one electrode to the other by overcoming the sheaths regions occurring transportation of particles agglomeration from one electrode to the other. The electrons injection has contributed to increase the plasma electron density peaks. These electrons populations have raised the generated electrostatic fields assisting the elemental ions emigration to a preferred electrode direction. Regardless of plasma electrodes positions and plasma shape, ions can be departed from one electrode to deposit on the other one. In consequence, as an application the AF plasma type can enhance the metal deposition from one electrode to the other.

  5. Dense Metal Plasma in a Solenoid for Ion Beam Neutralization

    SciTech Connect (OSTI)

    Anders, Andre; Kauffeldt, Marina; Oks, Efim M.; Roy, Prabir K.

    2010-10-30

    Space-charge neutralization is required to compress and focus a pulsed, high-current ion beam on a target for warm dense matter physics or heavy ion fusion experiments. We described approaches to produce dense plasma in and near the final focusing solenoid through which the ion beam travels, thereby providing an opportunity for the beam to acquire the necessary space-charge compensating electrons. Among the options are plasma injection from pulsed vacuum arc sources located outside the solenoid, and using a high current (> 4 kA) pulsed vacuum arc plasma from a ring cathode near the edge of the solenoid. The plasma distribution is characterized by photographic means, by an array of movable Langmuir probes, by a small single probe, and by evaluating Stark broadening of the Balmer H beta spectral line. In the main approach described here, the plasma is produced at several cathode spots distributed azimuthally on the ring cathode. It is shown that the plasma is essentially hollow, as determined by the structure of the magnetic field, though the plasma density exceeds 1014 cm-3 in practically all zones of the solenoid volume if the ring electrode is placed a few centimeters off the center of the solenoid. The plasma is non-uniform and fluctuating, however, since its density exceeds the ion beam density it is believed that this approach could provide a practical solution to the space charge neutralization challenge.

  6. High Energy Density Capacitors

    SciTech Connect (OSTI)

    2010-07-01

    BEEST Project: Recapping is developing a capacitor that could rival the energy storage potential and price of today’s best EV batteries. When power is needed, the capacitor rapidly releases its stored energy, similar to lightning being discharged from a cloud. Capacitors are an ideal substitute for batteries if their energy storage capacity can be improved. Recapping is addressing storage capacity by experimenting with the material that separates the positive and negative electrodes of its capacitors. These separators could significantly improve the energy density of electrochemical devices.

  7. 2013 Plasma Camp | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Camp View larger image View larger image View larger image View larger image View larger image View larger image View larger image

  8. Nonlinear plasma wave in magnetized plasmas

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991; Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 ; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Hosokai, Tomonao; Zhidkov, Alexei G.; Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 ; Kodama, Ryosuke; Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  9. Bradbury Science Museum - Science on Wheels

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bradbury Science Museum - Science on Wheels Our Mission: To stimulate interest in and enthusiasm for science, technology, engineering and mathematics and promote public understanding and appreciation of Los Alamos National Laboratory Our Vision: The public interested in and excited about science, technology, engineering and mathematics, and the work of Los Alamos National Laboratory Program Description During the school year, the Bradbury Science Museum Educators drive there van to schools

  10. DOE and Fusion Links | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DOE and Fusion Links United States Department of Energy U.S. Department of Energy Office of Science Office of Fusion Energy Sciences U.S. D.O.E. Princeton Site Office Map showing U.S. Fusion Program Participants U.S. D.O.E. Science Laboratories U.S. D.O.E. User Facilities U.S. D.O.E. Funding Opportunities Other Fusion Research Sites United States Sites General Atomics (GA) MIT Plasma Science and Fusion Center U.S. ITER National Ignition Facility (NIF) American Fusion News International Sites

  11. Office of Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Office of Science /science-innovation/_assets/images/icon-science.jpg Office of Science Enabling remarkable discoveries and tools that transform our understanding of energy and matter and advance national, economic, and energy security. Advanced Scientific Computing Research» Basic Energy Sciences» Biological and Environmental Research» Fusion Energy Sciences» High Energy Physics» Nuclear Physics» Fusion Energy Science Research LANL fusion materials researchers use Titan supercomputer to

  12. Capabilities: Science Pillars

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pillars /science-innovation/_assets/images/icon-science.jpg Capabilities: Science Pillars The Lab's four Science Pillars harness our scientific capabilities for national security solutions. What are the Los Alamos National Laboratory's Science Pillars? The Laboratory has established the Science Pillars under four main themes to bring together the Laboratory's diverse array of scientific capabilities and expertise: Information, Science, and Technology Pillar Materials for the Future Pillar

  13. Princeton Plasma Physics Laboratory. Annual report, October 1, 1989--September 30, 1990

    SciTech Connect (OSTI)

    Not Available

    1990-12-31

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  14. Characterization of a Filtered High Current Pulsed Cathodic Vacuum Arc Plasma Source: Plasma Transport Analysis

    SciTech Connect (OSTI)

    Sangines, R.; Tarrant, R. N.; Bilek, M. M. M.; McKenzie, D. R.; Andruczyk, D.

    2008-03-19

    Studies of plasma behavior produced by a filtered high current pulsed cathodic vacuum arc system are reported. Titanium plasma is initiated from the cathode by surface flash over triggering at the centre of the cathode disk. The multiple arc spots move outwards due to their mutual repulsion and the arc current pulse is terminated as the arc spots reach the edge of the cathode disk. The plasma moves into a positively biased quarter-torus magnetic filter and is guided towards the substrate position located 150 mm beyond the filter exit. Electron density and plasma current measurements have been employed to analyze the transport of the plasma associated with different cathode currents, and its dependence on confining magnetic field and bias conditions. For a given cathode current, the optimum plasma transport to the substrate requires the right combination of the strength of the confining magnetic field and the magnetic filter positive bias. The optimum values of these two parameters were found to increase with increasing cathode current. Initially the optimum throughput of plasma increases more strongly than the arc current (roughly 1.5 times the increase in the current); however, at high cathode current regimes (2.4 kA) a significant change of the plasma behavior is seen and transport efficiency is reduced.

  15. Determination of the transient electron temperature in a femtosecond-laser-induced air plasma filament

    SciTech Connect (OSTI)

    Sun Zhanliang; Chen Jinhai; Rudolph, Wolfgang

    2011-04-15

    The transient electron temperature in a weakly ionized femtosecond-laser-produced air plasma filament was determined from optical absorption and diffraction experiments. The electron temperature and plasma density decay on similar time scales of a few hundred picoseconds. Comparison with plasma theory reveals the importance of inelastic collisions that lead to energy transfer to vibrational degrees of freedom of air molecules during the plasma cooling.

  16. Diagnosis of femtosecond plasma filament by channeling microwaves along the filament

    SciTech Connect (OSTI)

    Alshershby, Mostafa; Ren, Yu; Qin, Jiang; Hao, Zuoqiang; Lin, Jingquan

    2013-05-20

    We introduce a simple, fast, and non-intrusive experimental method to obtain the basic parameters of femtosecond laser-generated plasma filament. The method is based on the channeling of microwaves along both a plasma filament and a well-defined conducting wire. By comparing the detected microwaves that propagate along the plasma filament and a copper wire with known conductivity and spatial dimension, the basic parameters of the plasma filament can be easily obtained. As a result of the possibility of channeling microwave radiation along the plasma filament, we were then able to obtain the plasma density distribution along the filament length.

  17. Low density microcellular foams

    DOE Patents [OSTI]

    LeMay, J.D.

    1991-11-19

    Disclosed is a process of producing microcellular foam which comprises the steps of: (a) selecting a multifunctional epoxy oligomer resin; (b) mixing said epoxy resin with a non-reactive diluent to form a resin-diluent mixture; (c) forming a diluent containing cross-linked epoxy gel from said resin-diluent mixture; (d) replacing said diluent with a solvent therefore; (e) replacing said solvent with liquid carbon dioxide; and (f) vaporizing off said liquid carbon dioxide under supercritical conditions, whereby a foam having a density in the range of 35-150 mg/cc and cell diameters less than about 1 [mu]m is produced. Also disclosed are the foams produced by the process. 8 figures.

  18. Low density microcellular foams

    DOE Patents [OSTI]

    LeMay, James D. (Castro Valley, CA)

    1991-01-01

    Disclosed is a process of producing microcellular foam which comprises the steps of: (a) selecting a multifunctional epoxy oligomer resin; (b) mixing said epoxy resin with a non-reactive diluent to form a resin-diluent mixture; (c) forming a diluent containing cross-linked epoxy gel from said resin-diluent mixture; (d) replacing said diluent with a solvent therefore; (e) replacing said solvent with liquid carbon dioxide; and (f) vaporizing off said liquid carbon dioxide under supercritical conditions, whereby a foam having a density in the range of 35-150 mg/cc and cell diameters less than about 1 .mu.m is produced. Also disclosed are the foams produced by the process.

  19. Low density microcellular foams

    DOE Patents [OSTI]

    LeMay, James D. (Castro Valley, CA)

    1992-01-01

    Disclosed is a process of producing microcellular from which comprises the steps of: (a) selecting a multifunctional epoxy oligomer resin; (b) mixing said epoxy resin with a non-reactive diluent to form a resin-diluent mixture; (c) forming a diluent containing cross-linked epoxy gel from said resin-diluent mixture; (d) replacing said diluent with a solvent therefore; (e) replacing said solvent with liquid carbon dioxide; and (f) vaporizing off said liquid carbon dioxide under supercritical conditions, whereby a foam having a density in the range of 35-150 mg/cc and cell diameters less than about 1 .mu.m is produced. Also disclosed are the foams produced by the process.

  20. Low density microcellular foams

    DOE Patents [OSTI]

    Aubert, James H. (Albuquerque, NM); Clough, Roger L. (Albuquerque, NM); Curro, John G. (Placitas, NM); Quintana, Carlos A. (Albuquerque, NM); Russick, Edward M. (Albuquerque, NM); Shaw, Montgomery T. (Mansfield Center, CT)

    1987-01-01

    Low density, microporous polymer foams are provided by a process which comprises forming a solution of polymer and a suitable solvent followed by rapid cooling of the solution to form a phase-separated system and freeze the phase-separated system. The phase-separated system comprises a polymer phase and a solvent phase, each of which is substantially continuous within the other. The morphology of the polymer phase prior to and subsequent to freezing determine the morphology of the resultant foam. Both isotropic and anisotropic foams can be produced. If isotropic foams are produced, the polymer and solvent are tailored such that the solution spontaneously phase-separates prior to the point at which any component freezes. The morphology of the resultant polymer phase determines the morphology of the resultant foam and the morphology of the polymer phase is retained by cooling the system at a rate sufficient to freeze one or both components of the system before a change in morphology can occur. Anisotropic foams are produced by forming a solution of polymer and solvent that will not phase separate prior to freezing of one or both components of the solution. In such a process, the solvent typically freezes before phase separation occurs. The morphology of the resultant frozen two-phase system determines the morphology of the resultant foam. The process involves subjecting the solution to essentially one-dimensional cooling. Means for subjecting such a solvent to one-dimensional cooling are also provided. Foams having a density of less than 0.1 g/cc and a uniform cell size of less than 10 .mu.m and a volume such that the foams have a length greater than 1 cm are provided.