The CPS Plasma Award at the Intel Science and Engineering Fair

NASA Astrophysics Data System (ADS)

Berry, Lee

2012-10-01

For the past eight years, the Coalition for Plasma Science (CPS) has presented an award for a plasma project at the Intel International Science and Engineering Fair (ISEF). We reported on the first five years of this award at the 2009 DPP Symposium. Pulsed neutron-producing experiments are a recurring topic, with the efforts now turning to applications. The most recent award at the Pittsburgh ISEF this past May was given for analysis of data from Brookhaven's Relativistic Heavy Ion Collider. The effort had the goal of understanding the fluid properties of the quark-gluon plasma. All of the CPS award-winning projects so far have been based on experiments, with four awards going to women students and four to men. In 2009 we noted that the number and quality of projects was improving. Since then, as we we predicted (hoped for), that trend has continued. The CPS looks forward to continuing its work with students who are excited about the possibilities of plasma. You too can share this excitement by judging at the 2013 fair in Phoenix on May 12-17. Information may be obtained by emailing cps@plasmacoalition.org.

Helping Teachers Teach Plasma Physics

NASA Astrophysics Data System (ADS)

Correll, Donald

2008-11-01

Lawrence Livermore National Laboratory's E/O program in Fusion Science and Plasma Physics now includes both `pre-service' as well as `in-service' high school science teacher professional development activities. Teachers are instructed and mentored by `master teachers' and LLNL plasma researchers working in concert. The Fusion/Plasma E/O program exploits a unique science education partnership that exists between LLNL's Science Education Program and the UC Davis Edward Teller Education Center. For `in-service' teachers, the Fusion & Astrophysics Teacher Research Academy (TRA) has four levels of workshops that are designed to give in-service high school science teachers experience in promoting and conducting research, most notably in the filed of plasma spectroscopy. Participating teachers in all four TRA levels may earn up to ten units of graduate credit from Cal-State University East Bay, and may apply these units toward a Masters of Science in Education. For `pre-service' teachers, the Science Teacher and Researcher (STAR) program, as a partnership with the California State University System, includes attracting undergraduate science majors to teaching careers by allowing them to pursue professional identities as both a research scientist as well as a science teacher. Participating `pre-service' STAR students are provided research internships at LLNL and work closely with the `in-service' TRA teachers. Results from the continuum `pre-service' to `in-service' science teacher professional development programs will be presented.

Plasma Science and Innovation Center (PSI-Center) at Washington, Wisconsin, and Utah State, ARRA Supplement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sovinec, Carl

The objective of the Plasma Science and Innovation Center (PSI-Center) is to develop and deploy computational models that simulate conditions in smaller, concept-exploration plasma experiments. The PSIC group at the University of Wisconsin-Madison, led by Prof. Carl Sovinec, uses and enhances the Non-Ideal Magnetohydrodynamics with Rotation, Open Discussion (NIMROD) code, to simulate macroscopic plasma dynamics in a number of magnetic confinement configurations. These numerical simulations provide information on how magnetic fields and plasma flows evolve over all three spatial dimensions, which supplements the limited access of diagnostics in plasma experiments. The information gained from simulation helps explain how plasma evolves.more » It is also used to engineer more effective plasma confinement systems, reducing the need for building many experiments to cover the physical parameter space. The ultimate benefit is a more cost-effective approach to the development of fusion energy for peaceful power production. The supplemental funds provided by the American Recovery and Reinvestment Act of 2009 were used to purchase computer components that were assembled into a 48-core system with 256 Gb of shared memory. The system was engineered and constructed by the group's system administrator at the time, Anthony Hammond. It was successfully used by then graduate student, Dr. John O'Bryan, for computing magnetic relaxation dynamics that occur during experimental tests of non-inductive startup in the Pegasus Toroidal Experiment (pegasus.ep.wisc.edu). Dr. O'Bryan's simulations provided the first detailed explanation of how the driven helical filament of electrical current evolves into a toroidal tokamak-like plasma configuration.« less

Electrodeless Plasma Source: Phase II Update

NASA Astrophysics Data System (ADS)

Prager, James; Ziemba, Timothy; Miller, Kenneth

2012-10-01

Eagle Harbor Technologies, in collaboration with the University of Washington, has developed a low-impurity, electrode-less plasma source (EPS) for start-up and source plasma injection for fusion science applications. In order to not interfere with the experiment, a pre-ionizer/plasma source must meet a few critical criteria including low impurity production, low electromagnetic interference (EMI), and minimal disruption to the magnetic geometry of the experiment. This system was designed to be UHV compatible and bakable. Here we present the results of the EPS Phase II upgrade. The output plasma density was increased by two orders of magnitude to >10^17 m-3 in hydrogen with no magnetic field injected. EPS system integration with the HIT-SI experiment has begun.

Numerical design of a magnetized turbulence experiment at the National Ignition Facility

NASA Astrophysics Data System (ADS)

Feister, Scott; Tzeferacos, Petros; Meinecke, Jena; Bott, Archie; Caprioli, Damiano; Laune, Jt; Bell, Tony; Casner, Alexis; Koenig, Michel; Li, Chikang; Miniati, Francesco; Petrasso, Richard; Remington, Bruce; Reville, Brian; Ross, J. Steven; Ryu, Dongsu; Ryutov, Dmitri; Sio, Hong; Turnbull, David; Zylstra, Alex; Schekochihin, Alexander; Froula, Dustin; Park, Hye-Sook; Lamb, Don; Gregori, Gianluca

2017-10-01

The origin and amplification of magnetic fields remains an active astrophysical research topic. We discuss design (using three-dimensional FLASH simulations) of a magnetized turbulence experiment at the National Ignition Facility (NIF). NIF lasers drive together two counter-propagating plasma flows to form a hot, turbulent plasma at the center. In the simulations, plasma temperatures are high enough to reach super-critical values of magnetic Reynolds number (Rm). Biermann battery seed magnetic fields (generated during laser-target interaction) are advected into the turbulent region and amplified by fluctuation dynamo in the above-unity Prandtl number regime. Plasma diagnostics are modeled with FLASH for planning and direct comparison with NIF experimental data. This work was supported in part at the University of Chicago by the DOE NNSA, the DOE Office of Science, and the NSF. The numerical simulations were conducted at ALCF's Mira under the auspices of the DOE Office of Science ALCC program.

Making of the NSTX Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

C. Neumeyer; M. Ono; S.M. Kaye

1999-11-01

The NSTX (National Spherical Torus Experiment) facility located at Princeton Plasma Physics Laboratory is the newest national fusion science experimental facility for the restructured US Fusion Energy Science Program. The NSTX project was approved in FY 97 as the first proof-of-principle national fusion facility dedicated to the spherical torus research. On Feb. 15, 1999, the first plasma was achieved 10 weeks ahead of schedule. The project was completed on budget and with an outstanding safety record. This paper gives an overview of the NSTX facility construction and the initial plasma operations.

The Demonstration and Science Experiments (DSX) Mission

NASA Astrophysics Data System (ADS)

McCollough, J. P., II; Johnston, W. R.; Starks, M. J.; Albert, J.

2015-12-01

In 2016, the Air Force Research Laboratory will launch its Demonstration and Science Experiments mission to investigate wave-particle interactions and the particle and space environment in medium Earth orbit (MEO). The DSX spacecraft includes three experiment packages. The Wave Particle Interaction Experiment (WPIx) will perform active and passive investigations involving VLF waves and their interaction with plasma and energetic electrons in MEO. The Space Weather Experiment (SWx) includes five particle instruments to survey the MEO electron and proton environment. The Space Environmental Effects Experiment (SFx) will investigate effects of the MEO environment on electronics and materials. We will describe the capabilities of the DSX science payloads, science plans, and opportunities for collaborative studies such as conjunction observations and far-field measurements.

Computations in Plasma Physics.

ERIC Educational Resources Information Center

Cohen, Bruce I.; Killeen, John

1983-01-01

Discusses contributions of computers to research in magnetic and inertial-confinement fusion, charged-particle-beam propogation, and space sciences. Considers use in design/control of laboratory and spacecraft experiments and in data acquisition; and reviews major plasma computational methods and some of the important physics problems they…

Overview of the HIT-SI3 spheromak experiment

NASA Astrophysics Data System (ADS)

Hossack, A. C.; Jarboe, T. R.; Chandra, R. N.; Morgan, K. D.; Sutherland, D. A.; Everson, C. J.; Penna, J. M.; Nelson, B. A.

2017-10-01

The HIT-SI and HIT-SI3 spheromak experiments (a = 23 cm) study efficient, steady-state current drive for magnetic confinement plasmas using a novel method which is ideal for low aspect ratio, toroidal geometries. Sustained spheromaks show coherent, imposed plasma motion and low plasma-generated mode activity, indicating stability. Analysis of surface magnetic fields in HIT-SI indicates large n = 0 and 1 mode amplitudes and little energy in higher modes. Within measurement uncertainties all the n = 1 energy is imposed by the injectors, rather than being plasma-generated. The fluctuating field imposed by the injectors is sufficient to sustain the toroidal current through dynamo action whereas the plasma-generated field is not (Hossack et al., Phys. Plasmas, 2017). Ion Doppler spectroscopy shows coherent, imposed plasma motion inside r 10 cm in HIT-SI and a smaller volume of coherent motion in HIT-SI3. Coherent motion indicates the spheromak is stable and a lack of plasma-generated n = 1 energy indicates the maximum q is maintained below 1 for stability during sustainment. In HIT-SI3, the imposed mode structure is varied to test the plasma response (Hossack et al., Nucl. Fusion, 2017). Imposing n = 2, n = 3, or large, rotating n = 1 perturbations is correlated with transient plasma-generated activity. Work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences, under Award Number DE-FG02-96ER54361.

Dose Measurements in a 20-J Repetitive Plasma Focus

NASA Astrophysics Data System (ADS)

Goudarzi, S.; Babaee, H.; Esmaeli, A.; Nasiri, A.; Mazandarani, A.

2018-02-01

In this article, the results of X-ray dose measurements executed using thermoluminescent dosimeters in experiments with a very small (20 J) repetitive plasma focus device named SORENA-1 are presented and analyzed. The working gas in these experiments was Argon. Also, pinch formation in experiments with this device has been observed. This device has been designed and constructed in Plasma and Nuclear Fusion Research School of Nuclear Science and Technology Research Institute of Iran. From these results, it is concluded that we can do experiments with this device using Ar as working gas all over the working days of year, and a good symmetry for measured dose around the device has been seen.

Charged dust phenomena in the near-Earth space environment.

PubMed

Scales, W A; Mahmoudian, A

2016-10-01

Dusty (or complex) plasmas in the Earth's middle and upper atmosphere ultimately result in exotic phenomena that are currently forefront research issues in the space science community. This paper presents some of the basic criteria and fundamental physical processes associated with the creation, evolution and dynamics of dusty plasmas in the near-Earth space environment. Recent remote sensing techniques to probe naturally created dusty plasma regions are also discussed. These include ground-based experiments employing high-power radio wave interaction. Some characteristics of the dusty plasmas that are actively produced by space-borne aerosol release experiments are discussed. Basic models that may be used to investigate the characteristics of such dusty plasma regions are presented.

A review of astrophysics experiments on intense lasers

NASA Astrophysics Data System (ADS)

Remington, B. A.

1999-11-01

Modern, high power laser facilities open new possibilities for simulating astrophysical systems in the laboratory.(S.J. Rose, Laser & Part. Beams 9, 869 (1991); B.H. Ripin et al., Laser & Part. Beams 8, 183 (1990); B.A. Remington et al., Science 284, 1488 (1999); H. Takabe et al., Plasma Phys. Contr. Fusion 41, A75 (1999); R.P. Drake, J. Geophys. Res. 104, 14505 (1999).) Scaled investigations of the hydrodynamics.(J. Kane et al., Phys. Plasmas 6, 2065 (1999); R.P. Drake et al., Ap. J. 500, L157 (1998); D. Ryutov et al., Ap. J. 518, 821 (1999).) and radiative transfer.(J. Wark et al., Phys. Plasmas 4, 2004 (1997); P.K. Patel et al., JQSRT 58, 835 (1997).) relevant to supernovae, and opacities relevant to stellar interiors.(F.J. Rogers and C.A. Iglesias, Science 263, 50 (1994); H. Merdji et al., JSQRT 58, 783 (1997).) are now possible with laser experiments. Equations of state relevant to the interiors of giant planets and brown dwarfs are also being experimentally accessed.(G.W. Collins et al., Science 281, 1178 (1998); A. Benuzzi et al., Phys. Rev. E 54, 2162 (1996).) With the construction of the NIF laser in the U.S., and the LIL and LMJ lasers in France, controlled investigations of thermonuclear burn physics will become possible in the next decade. And with existing and future ultra-high intensity short pulse lasers, investigations of relativistic astrophysical plasmas are becoming possible.(M.H. Key et al., Phys. Plasmas 5, 1966 (1998); F. Pegoraro et al., Plasma Phys. Contr. Fus. 39, B261 (1997).) A review of laboratory astrophysics experiments using intense lasers will be presented, and the potential for the future will be discussed.

A Platform for X-Ray Thomson Scattering Measurements of Radiation Hydrodynamics Experiments on the NIF

NASA Astrophysics Data System (ADS)

Lefevre, Heath; Ma, Kevin; Belancourt, Patrick; MacDonald, Michael; Doeppner, Tilo; Keiter, Paul; Kuranz, Carolyn

2017-10-01

A recent experiment on the National Ignition Facility (NIF) radiographed the evolution of the Rayleigh-Taylor (RT) instability under high and low drive cases. This experiment showed that under a high drive the growth rate of the RT instability is reduced relative to the low drive case. The high drive launches a radiative shock, increases the temperature of the post-shock region, and ablates the spikes, which reduces the RT growth rate. The plasma parameters must be measured to validate this claim. We present a target design for making X-Ray Thomson Scattering (XRTS) measurements on radiation hydrodynamics experiments on NIF to measure the electron temperature of the shocked region in the above cases. Specifically, we show that a previously fielded NIF radiation hydrodynamics platform can be modified to allow sufficient signal and temperature resolution for XRTS measurements. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956 and the National Science Foundation through the Basic Plasma Science and Engineering program.

Scientist in the Classroom: The First Year Highlights of a Plasma Outreach Program

NASA Astrophysics Data System (ADS)

Nagy, A.; Danielson, C. A.; Lee, R. L.; Winter, P. S.; Valentine, J. R.

1999-11-01

The General Atomics education program ``Scientist in the Classroom'' uses scientists, engineers, and technicians to discuss plasma physics with students in the classroom. A program goal is to make science an enjoyable experience while showing students how plasma physics plays an important role in their world. A fusion overview is presented, including topics on energy and environment. Using hands-on equipment, students manipulate plasma discharges using magnetic fields and observe their spectral properties. Students also observe physical properties of liquid nitrogen, infrared waves, and radioactive particles. The benefit of this program, relative to facility tours, is that it optimizes cost and scheduling between the scientific staff and students. This program and its equipment are receiving accolades as an adjunct teaching option available to schools at no cost. This year we have presented to over 1000 students at 11 schools. Student exit interviews reflect strong positive comments regarding their hands-on learning experience and science appreciation.

First Plasma Results from the Levitated Dipole Experiment

NASA Astrophysics Data System (ADS)

Garnier, Darren T.

2005-04-01

On August 13, 2004, the first plasma physics experiments were conducted using the Levitated Dipole Experiment(LDX)http://www.psfc.mit.edu/ldx/. LDX was built at MIT's Plasma Science and Fusion Center as a joint research project of Columbia University and MIT. LDX is a first-of-its-kind experiment incorporating three superconducting magnets and exploring the physics of high-temperature plasma confined by dipole magnetic fields, similar to planetary magnetospheres. It will test recent theories that suggest that stable, high-β plasma can be confined without good curvature or magnetic shear, instead using plasma compressibility to provide stability. (Plasma β is the ratio of plasma pressure to magnetic pressure.) In initial experiments, 750 kA of current was induced in the dipole coil which was physically supported in the center of the 5 m diameter vacuum chamber. Deuterium plasma discharges, lasting from 4 to 10 seconds, were formed with multi-frequency ECRH microwave heating of up to 6.2 kW. Each plasma contained a large fraction of energetic and relativistic electrons that created a significant pressure that caused outward expansion of the magnetic field. Reconstruction of the magnetic equilibrium from external magnetic diagnostics indicate local peak plasma β 7 %. Along with an overview of the LDX device, results from numerous diagnostics operating during this initial supported campaign measuring the basic plasma parameters will be presented. In addition, observations of instabilities leading to rapid plasma loss and the effects of changing plasma compressibility will be explored.

The Earth's magnetosphere as a sample of the plasma universe

NASA Technical Reports Server (NTRS)

Faelthammar, Carl-Gunne

1986-01-01

Plasma processes in the Earth's neighborhood determine the environmental conditions under which space-based equipment for science or technology must operate. These processes are peculiar to a state of matter that is rare on Earth but dominates the universe as whole. The physical, and especially the electrodynamic, properties of this state of matter is still far from well understood. By fortunate circumstances, the magnetosphere-ionosphere system of the Earth provides a rich sample of widely different plasma populations, and, even more importantly, it is the site of a remarkable variety of plasma processes. In different combinations such processes must be important throughout the universe, which is overwhelmingly dominated by matter in the plasma state. Therefore, observations and experiments in the near-Earth plasma serve a multitude of purposes. They will not only (1) clarify the dynamics of the space environment but also (2) widen the understanding of matter, (3) form a basis for interpretating remote observations of astrophysical objects, thereby even (4) help to reconstruct events that led to the evolution of the solar system. Last but not least they will (5) provide know-how required for adapting space-based technology to the plasma environment. Such observations and experiments will require a close mutual interplay between science and technology.

Recent advances in plasma modeling for space applications

NASA Astrophysics Data System (ADS)

Srinivasan, Bhuvana; Scales, Wayne; Cagas, Petr; Glesner, Colin

2017-02-01

This paper presents a brief overview of the application of advanced plasma modeling techniques to several space science and engineering problems currently of significant interest. Recent advances in both kinetic and fluid modeling provide the ability to study a wide variety of problems that may be important to space plasmas including spacecraft-environment interactions, plasma-material interactions for propulsion systems such as Hall thrusters, ionospheric plasma instabilities, plasma separation from magnetic nozzles, active space experiments, and a host of additional problems. Some of the key findings are summarized here.

Observations at venus encounter by the plasma science experiment on mariner 10.

PubMed

Bridge, H S; Lazarus, A J; Scudder, J D; Ogilvie, K W; Hartle, R E; Asbridge, J R; Bame, S J; Feldman, W C; Siscoe, G L

1974-03-29

Preliminary results from the rearward-looking electrostatic analyzer of the plasma science experiment during the Mariner 10 encounter with Venus are described. They show that the solar-wind interaction with the planet probably involves a bow shock rather than an extended exosphere, but that this is not a thin boundary at the point where it was crossed by Mariner 10. An observed reduction in the flux of electrons with energies greater than 100 electron volts is interpreted as evidence for somne direct interaction with the exosphere. Unusual intermittent features observed downstream of the planet indicate the presence of a comet-like tail hundreds of scale lengths in length.

Observations at Venus encounter by the plasma science experiment on Mariner 10

NASA Technical Reports Server (NTRS)

Bridge, H. S.; Lazarus, A. J.; Scudder, J. D.; Ogilvie, K. W.; Hartle, R. E.; Asbridge, J. R.; Bame, S. J.; Feldman, W. C.; Siscoe, G. L.

1974-01-01

Preliminary results from the rearward-looking electrostatic analyzer of the plasma science experiment during the Mariner 10 encounter with Venus are described. They show that the solar-wind interaction with the planet probably involves a bow shock rather than an extended exosphere, but that this is not a thin boundary at the point where it was crossed by Mariner 10. An observed reduction in the flux of electrons with energies greater than 100 electron volts is interpreted as evidence for some direct interaction with the exosphere. Unusual intermittent features observed downstream of the planet indicate the presence of a comet-like tail hundreds of scale lengths in length.

PLASMA PHYSICS AND STATISTICAL MECHANICS IN BRUSSELS, BELGIUM,

DTIC Science & Technology

significant research in the theory and experiment of the Tonks-Dattner resonances in a cylindrical plasma column. The second visit was to Professors I ...Prigogine and R. Balescu , of the Faculte des Sciences, Universite Libre de Bruxelles, who together direct a large group of scientists working on all

Solar array module plasma interactions experiment (SAMPIE) - Science and technology objectives

NASA Technical Reports Server (NTRS)

Hillard, G. B.; Ferguson, Dale C.

1993-01-01

The solar array module plasma interactions experiment (SAMPIE) is an approved NASA flight experiment manifested for Shuttle deployment in early 1994. The SAMPIE experiment is designed to investigate the interaction of high voltage space power systems with ionospheric plasma. To study the behavior of solar cells, a number of solar cell coupons (representing design technologies of current interest) will be biased to high voltages to measure both arcing and current collection. Various theories of arc suppression will be tested by including several specially modified cell coupons. Finally, SAMPIE will include experiments to study the basic nature of arcing and current collection. This paper describes the rationale for a space flight experiment, the measurements to be made, and the significance of the expected results. A future paper will present a detailed discussion of the engineering design.

Spacelab Science Results Study. Volume 1; External Observations

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Compiler)

1999-01-01

Some of the 36 Spacelab missions were more or less dedicated to specific scientific disciplines, while other carried a eclectic mixture of experiments ranging from astrophysics to life sciences. However, the experiments can be logically classified into two general categories; those that make use of the Shuttle as an observing platform for external phenomena (including those which use the Shuttle in an interactive mode) and those which use the Shuttle as a microgravity laboratory. This first volume of this Spacelab Science Results study will be devoted to experiments of the first category. The disciplines included are Astrophysics, Solar Physics, Space Plasma Physics, Atmospheric Sciences, and Earth Sciences. Because of the large number of microgravity investigations, Volume 2 will be devoted to Microgravity Sciences, which includes Fluid Physics, Combustion Science, Materials Science, and Biotechnology, and Volume 3 will be devoted to Space Life Sciences, which studies the response and adaptability of living organisms to the microgravity environment.

Optimization of confocal laser induced fluorescence for long focal length applications

NASA Astrophysics Data System (ADS)

Jemiolo, Andrew J.; Henriquez, Miguel F.; Thompson, Derek S.; Scime, Earl E.

2017-10-01

Laser induced fluorescence (LIF) is a non-perturbative diagnostic for measuring ion and neutral particle velocities and temperatures in a plasma. The conventional method for single-photon LIF requires intersecting optical paths for light injection and collection. The multiple vacuum windows needed for such measurements are unavailable in many plasma experiments. Confocal LIF eliminates the need for perpendicular intersecting optical paths by using concentric injection and collection paths through a single window. One of the main challenges with using confocal LIF is achieving high resolution measurements at the longer focal lengths needed for many plasma experiments. We present confocal LIF measurements in HELIX, a helicon plasma experiment at West Virginia University, demonstrating spatial resolution dependence on focal length and spatial filtering. By combining aberration mitigating optics with spatial filtering, our results show high resolution measurements at focal lengths of 0.5 m, long enough to access the interiors of many laboratory plasma experiments. This work was supported by U.S. National Science Foundation Grant No. PHY-1360278.

AMPS sciences objectives and philosophy. [Atmospheric, Magnetospheric and Plasmas-in-Space project on Spacelab

NASA Technical Reports Server (NTRS)

Schmerling, E. R.

1975-01-01

The Space Shuttle will open a new era in the exploration of earth's near-space environment, where the weight and power capabilities of Spacelab and the ability to use man in real time add important new features. The Atmospheric, Magnetospheric, and Plasmas-in-Space project (AMPS) is conceived of as a facility where flexible core instruments can be flown repeatedly to perform different observations and experiments. The twin thrusts of remote sensing of the atmosphere below 120 km and active experiments on the space plasma are the major themes. They have broader implications in increasing our understanding of plasma physics and of energy conversion processes elsewhere in the universe.

First Spacelab mission status and lessons learned

NASA Technical Reports Server (NTRS)

Craft, H. G., Jr.; Smith, M. J.; Mullinger, D.

1982-01-01

There are 38 experiments and/or facilities currently under development, or undergoing testing, which will be incorporated into Spacelab for its first mission. These experiments cover a range of scientific disciplines which includes atmospheric research, life sciences, space plasma research, materials science, and space industrialization technology. In addition to the full development of individual experiments, the final design of the integrated payload and the development of all requisite integration hardware have been accomplished. Attention is given to the project management lessons learned during payload integration development.

Atomic kinetics of a neon photoionized plasma experiment at Z

NASA Astrophysics Data System (ADS)

Mayes, D. C.; Mancini, R. C.; Schoenfeld, R. P.; Bailey, J. E.; Loisel, G. P.; Rochau, G. A.; ZAPP Collaboration

2017-10-01

We discuss an experimental effort to study the atomic kinetics in neon photoionized plasmas via K-shell line absorption spectroscopy. The experiment employs the intense x-ray flux emitted at the collapse of a Z-pinch to heat and backlight a photoionized plasma contained within a cm-scale gas cell placed at various distances from the Z-pinch and filled with neon gas pressures in the range from 3.5 to 120 Torr. The experimental platform affords an order of magnitude range in the ionization parameter characterizing the photoionized plasma from about 5 to 80 erg*cm/s. Thus, the experiment allows for the study of trends in ionization distribution as a function of the ionization parameter. An x-ray crystal spectrometer capable of collecting both time-integrated and time-gated data is used to collect absorption spectra. The spectra show line absorption by several ionization stages of neon, including Be-, Li-, He-, and H-like ions. Analysis of these spectra yields ion areal-densities and charge state distributions, which can be compared with results from atomic kinetics codes. In addition, the electron temperature is extracted from level population ratios of nearby energy levels in Li- and Be-like ions, which can be used to test heating models of photoionized plasmas. This work was sponsored in part by DOE Office of Science Grant DE-SC0014451, and the Z Facility Fundamental Science Program of SNL.

The WIND-HAARP Experiment: Initial Results of High Power Radiowave Interactions with Space Plasmas

DTIC Science & Technology

1997-11-10

Results from the first science experiment with the new HF Active Auroral Research Program ( HAARP ) facility in Alaska are reported. The initial...experiments involved transmission of high frequency waves from HAARP to the NASA/WIND satellite. The objective was to investigate the effects of space

Guerilla Science: Outreach at music and art festival

NASA Astrophysics Data System (ADS)

Rosin, Mark

2012-10-01

Guerilla Science a non-profit science education organization that, since 2007, has brought live events to unconventional venues for science, such as music festivals, art galleries, banquets, department stores and theaters. Guerilla Science sets science free by taking it out of the lab and into the traditional domains of the arts. By producing events that mix science with art, music and play, they create unique opportunities for adult audiences to experience science in unorthodox ways, such as interactive events, games, live experiments, demonstrations and performances by academics, artists, musicians, actors, and professional science communicators. Much of Guerilla Science's work has focused on astrophysical and terrestrial plasmas, and this presentation will provide an overview of Guerilla Science's work in this area. Guerilla Science has produced over twenty events, receiving international media coverage, and directly reached over fifteen thousand members of the public.

Modeling experimental plasma diagnostics in the FLASH code: Thomson scattering

NASA Astrophysics Data System (ADS)

Weide, Klaus; Flocke, Norbert; Feister, Scott; Tzeferacos, Petros; Lamb, Donald

2017-10-01

Spectral analysis of the Thomson scattering of laser light sent into a plasma provides an experimental method to quantify plasma properties in laser-driven plasma experiments. We have implemented such a synthetic Thomson scattering diagnostic unit in the FLASH code, to emulate the probe-laser propagation, scattering and spectral detection. User-defined laser rays propagate into the FLASH simulation region and experience scattering (change in direction and frequency) based on plasma parameters. After scattering, the rays propagate out of the interaction region and are spectrally characterized. The diagnostic unit can be used either during a physics simulation or in post-processing of simulation results. FLASH is publicly available at flash.uchicago.edu. U.S. DOE NNSA, U.S. DOE NNSA ASC, U.S. DOE Office of Science and NSF.

Computer Simulation of Compression and Energy Release upon Laser Irradiation of Cylindrically Symmetric Target

NASA Astrophysics Data System (ADS)

Kuzenov, V. V.

2017-12-01

The paper is devoted to the theoretical and computational study of compression and energy release for magneto-inertial plasma confinement. This approach makes it possible to create new high-density plasma sources, apply them in materials science experiments, and use them in promising areas of power engineering.

Experimental studies of collisional plasma shocks and plasma interpenetration via merging supersonic plasma jets

NASA Astrophysics Data System (ADS)

Hsu, S. C.; Moser, A. L.; Merritt, E. C.; Adams, C. S.

2015-11-01

Over the past 4 years on the Plasma Liner Experiment (PLX) at LANL, we have studied obliquely and head-on-merging supersonic plasma jets of an argon/impurity or hydrogen/impurity mixture. The jets are formed/launched by pulsed-power-driven railguns. In successive experimental campaigns, we characterized the (a) evolution of plasma parameters of a single plasma jet as it propagated up to ~ 1 m away from the railgun nozzle, (b) density profiles and 2D morphology of the stagnation layer and oblique shocks that formed between obliquely merging jets, and (c) collisionless interpenetration transitioning to collisional stagnation between head-on-merging jets. Key plasma diagnostics included a fast-framing CCD camera, an 8-chord visible interferometer, a survey spectrometer, and a photodiode array. This talk summarizes the primary results mentioned above, and highlights analyses of inferred post-shock temperatures based on observations of density gradients that we attribute to shock-layer thickness. We also briefly describe more recent PLX experiments on Rayleigh-Taylor-instability evolution with magnetic and viscous effects, and potential future collisionless shock experiments enabled by low-impurity, higher-velocity plasma jets formed by contoured-gap coaxial guns. Supported by DOE Fusion Energy Sciences and LANL LDRD.

Radio Aurora Explorer : Mission overview and the science objectives

NASA Astrophysics Data System (ADS)

Bahcivan, H.; Cutler, J.; Buonocore, J.; Bennett, M.

2009-12-01

Radio Aurora Explorer (RAX) is the first CubeSat mission funded by the NSF Small Satellite Program as a collaborative research of SRI International and the University of Michigan. The mission is a ground-to-space bi-static radar experiment enabling exploration of small-scale turbulent ionospheric structures in the high latitudes not accessible from the ground or space alone. The primary science objective is to understand the microphysics of plasma instabilities that lead to meter-scale plasma turbulence in the form of field-aligned irregularities of electron density between the altitudes of 80 and 400 km. The best-known radar target for the mission is the Farley-Buneman (two-stream) instability occurring in the ionospheric E region when the convection electric field exceeds a threshold of ~20 mV/m. Other targets include spiky structures associated with electrostatic ion cyclotron waves, Post-Rosenbluth, lower, and upper hybrid waves. The science objectives are (1) to determine the altitude distribution of high-latitude ionospheric irregularities as a function of the convection electric field magnitude and direction, (2) to identify the plasma waves responsible for the scattering, and (3) to determine to what extent the irregularities are field-aligned? The mission will measure for the first time the 3-D k-spectrum of the irregularities, in particular measuring their magnetic field alignment. The irregularities will be irradiated by an incoherent scatter radar (PFISR for the first experiments) and the scattered radiation will form a hallow cone-shaped radio aurora into space as illustrated in the figure below. The satellite radar receiver will the scattered signals as the satellite passes through the radio aurora. Irregularity locations will be determined using the time delay between ISR transmissions and satellite receptions. Experiments throughout the lifetime of the mission will determine irregularity intensities as a function altitude, magnetic aspect angle, and as a function of plasma parameters such as convection electric field, plasma density, and temperatures, which are measured effectively simultaneously by the ISR. In this regard, the mission is a well-controlled plasma experiment in a wall-less laboratory.

Pathway to STEM: Using Outreach Initiatives as a Method of Identifying, Educating and Recruiting the Next Generation of Scientists and Engineers

NASA Astrophysics Data System (ADS)

Ortiz-Arias, Deedee; Zwicker, Andrew; Dominguez, Arturo; Greco, Shannon

2017-10-01

The Princeton Plasma Physics Laboratory (PPPL) uses a host of outreach initiatives to inform the general population: the Young Women's Conference, Science Bowl, Science Undergraduate Laboratory Internship, My Brother's Keeper, a variety of workshops for university faculty and undergraduate students, public and scheduled lab tours, school and community interactive plasma science demonstrations. In addition to informing and educating the public about the laboratory's important work in the areas of Plasma and Fusion, these outreach initiatives, are also used as an opportunity to identify/educate/recruit the next generation of the STEM workforce. These programs provide the laboratory with the ability to: engage the next generation at different paths along their development (K-12, undergraduate, graduate, professional), at different levels of scientific content (science demonstrations, remote experiments, lectures, tours), in some instances, targeting underrepresented groups in STEM (women and minorities), and train additional STEM educators to take learned content into their own classrooms.

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. DeLooper; A. DeMeo; P. Lucas

The U. S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) has an energetic science education program and outreach effort. This overview describes the components of the programs and evaluates the changes that have occurred in this effort during the last several years. Efforts have been expanded to reach more students, as well as the public in general. The primary goal is to inform the public regarding the fusion and plasma research at PPPL and to excite students so that they can appreciate science and technology. A student's interest in science can be raised by tours, summer research experiences, in-classroommore » presentations, plasma expos, teacher workshops and web-based materials. The ultimate result of this effort is a better-informed public, as well as an increase in the number of women and minorities who choose science as a vocation. Measuring the results is difficult, but current metrics are reviewed. The science education and outreach programs are supported by a de dicated core group of individuals and supplemented by other members of the PPPL staff and consultants who perform various outreach and educational activities.« less

Progress in magnet design activities for the material plasma exposure experiment

DOE PAGES

Duckworth, Robert; Lumsdaine, Arnold; Rapp, Juergen; ...

2017-07-01

One of the critical challenges for the development of next generation fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or DEMO, is the understanding of plasma material interactions (PMI). Making progress in PMI research will require integrated facilities that can provide the types of conditions that will be seen in the first wall and divertor regions of future fusion facilities. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX), is proposed. In order to generate high ion fluence to simulate fusion divertor conditions, a steady-state plasma will be generated andmore » confined with superconducting magnets. Finally, the on-axis fields will range from 1 to 2.5 T in order to meet the requirements of the various plasma source and heating systems. Details on the pre-conceptual design of the magnets and cryogenic system are presented.« less

Diagnostics for the plasma liner experiment.

PubMed

Lynn, A G; Merritt, E; Gilmore, M; Hsu, S C; Witherspoon, F D; Cassibry, J T

2010-10-01

The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ∼0.1 Mbar using ∼1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)∼10(16) cm(-3), T(e)≈T(i)∼1 eV at the plasma gun mouth to n(i)>10(19) cm(-3), T(e)≈T(i)∼0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

Status and future prospects of laser fusion and high power laser applications

NASA Astrophysics Data System (ADS)

Mima, Kunioki

2010-08-01

In Asia, there are many institutes for the R&D of high power laser science and applications. They are 5 major institutes in Japan, 4 major institutes in China, 2 institutes in Korea, and 3 institutes in India. The recent achievements and future prospects of those institutes will be over viewed. In the laser fusion research, the FIREX-I project in Japan has been progressing. The 10kJ short pulse LFEX laser has completed and started the experiments with a single beam. About 1kJ pulse energy will be injected into a cone target. The experimental results of the FIREX experiments will be presented. As the target design for the experiments, a new target, namely, a double cone target was proposed, in which the high energy electrons are well confined and the heating efficiency is significantly improved. Together with the fusion experiments, Osaka University has carried out laboratory astrophysics experiments on photo ionizing plasmas to observe a unique X-ray spectrum from non-LTE plasmas. In 2008, Osaka university has started a new Photon research center in relation with the new program: Consortium for Photon Science and Technology: C-PhoST, in which ultra intense laser plasmas research and related education will be carried out for 10 years. At APRI, JAEA, the fundamental science on the relativistic laser plasmas and the applications of laser particle acceleration has been developed. The application of laser ion acceleration has been investigated on the beam cancer therapy since 2007. In China, The high power glass laser: Shenguan-II and a peta watt beam have been operated to work on radiation hydro dynamics at SIOFM Shanghai. The laser material and optics are developed at SIOFM and LFRC. The IAPCM and the IOP continued the studies on radiation hydrodynamics and on relativistic laser plasmas interactions. At LFRC in China, the construction of Shenguan III glass laser of 200kJ in blue has progressed and will be completed in 2012. Together with the Korean program, I will overview the above Asian programs.

Kuipers holds the Plasma-03 experiment container as Foale looks on during Expedition 9 / Expedition 8

NASA Image and Video Library

2004-04-29

ISS008-E-22393 (29 April 2004) --- European Space Agency (ESA) astronaut Andre Kuipers of the Netherlands, holds a Complex “Plasma-03” canister in the Zvezda Service Module of the International Space Station (ISS). Astronaut C. Michael Foale, Expedition 8 commander and NASA ISS science officer, is at right.

Studies of beam plasma interactions in a space simulation chamber using prototype Space Shuttle instruments

NASA Technical Reports Server (NTRS)

Banks, P. M.; Raitt, W. J.; Denig, W. F.

1982-01-01

In March, 1981, electron beam experiments were conducted in a large space simulation chamber using equipment destined to be flown aboard NASA's Office of Space Science-1 pallet (OSS-1). Two major flight experiments were involved. They include the Vehicle Charging and Potential (VCAP) experiment and the Plasma Diagnostics Package (PDP). Apparatus connected with VCAP included a Fast Pulse Electron Gun (FPEG), and a Charge and Current Probe (CCP). A preliminary view is provided of the results obtained when the electron emissions were held steady over relatively long periods of time such that steady state conditions could be obtained with respect to the electron beam interaction with the neutral gases and plasma of the vacuum chamber. Of particular interest was the plasma instability feature known as the Beam Plasma Discharge. For the present experiments the FPEG was used in a dc mode with a range of currents of 2 to 80 mA at a beam energy of 970 eV. Attention is given to the emissions of VLF and HF noise associated with the dc beam.

Development of Technologies to Utilize Laser Plasma Radiations Sources for Radiation Effects Sciences

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, J F

2007-01-31

This final report will cover work performed over the period of November 11, 2005 to September 30, 2006 on the contract to develop technologies using laser sources for radiation effects sciences. The report will discuss four topic areas; the laser source experiments on the Gekko Laser at Osaka, Japan, planning for the Charge State Freeze Out experiments to be performed in calendar year 2007, a review of previous xenon gasbags on the LANL Trident laser to provide planning support to the May-June 2007 HELEN experiments.

Spacelab Science Results Study

NASA Technical Reports Server (NTRS)

Naumann, R. J.; Lundquist, C. A.; Tandberg-Hanssen, E.; Horwitz, J. L.; Germany, G. A.; Cruise, J. F.; Lewis, M. L.; Murphy, K. L.

2009-01-01

Beginning with OSTA-1 in November 1981 and ending with Neurolab in March 1998, a total of 36 Shuttle missions carried various Spacelab components such as the Spacelab module, pallet, instrument pointing system, or mission peculiar experiment support structure. The experiments carried out during these flights included astrophysics, solar physics, plasma physics, atmospheric science, Earth observations, and a wide range of microgravity experiments in life sciences, biotechnology, materials science, and fluid physics which includes combustion and critical point phenomena. In all, some 764 experiments were conducted by investigators from the U.S., Europe, and Japan. The purpose of this Spacelab Science Results Study is to document the contributions made in each of the major research areas by giving a brief synopsis of the more significant experiments and an extensive list of the publications that were produced. We have also endeavored to show how these results impacted the existing body of knowledge, where they have spawned new fields, and if appropriate, where the knowledge they produced has been applied.

Properties of the ion-ion hybrid resonator in fusion plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morales, George J.

2015-10-06

The project developed theoretical and numerical descriptions of the properties of ion-ion hybrid Alfvén resonators that are expected to arise in the operation of a fusion reactor. The methodology and theoretical concepts were successfully compared to observations made in basic experiments in the LAPD device at UCLA. An assessment was made of the excitation of resonator modes by energetic alpha particles for burning plasma conditions expected in the ITER device. The broader impacts included the generation of basic insight useful to magnetic fusion and space science researchers, defining new avenues for exploration in basic laboratory experiments, establishing broader contacts betweenmore » experimentalists and theoreticians, completion of a Ph.D. dissertation, and promotion of interest in science through community outreach events and classroom instruction.« less

Science in orbit: The shuttle and spacelab experience, 1981-1986

NASA Technical Reports Server (NTRS)

1988-01-01

Significant achievements across all scientific disciplines and missions for the first six years of Shuttle flights are presented. Topics covered include science on the Space Shuttle and Spacelab, living and working in space, studying materials and processes in microgravity, observing the sun and earth, space plasma physics, atmospheric science, astronony and astrophysics, and testing new technology in space. Future research aboard the Shuttle/Spacelab is also briefly mentioned.

Characterization and Mitigation of ICRF Antenna - Plasma Edge Interaction

NASA Astrophysics Data System (ADS)

Hong, Rongjie; Tynan, George; Wukitch, Steve; Lin, Yijun; Terry, Jim; Chilenski, M.; Golfinopoulos, T.; Hubbard, A.; Mumgaard, R. T.; Perkins, R.; Reinke, M. L.; Alcator C-Mod Team

2017-10-01

Recent experiments reveal that RF-induced potentials (VRF) in the SOL and impurity source at the antenna can be reduced to background levels via optimizing the power ratio between the inner and outer current straps, Pcent /Pout . Experiments indicate the antenna impurity source reduction for the field aligned antenna is due to geometrical alignment rather than electrical symmetry. Additional experiments performed without an optimized Pcent /Pout showed that VRF and the associated convection cells do not influence the impurity penetration or core impurity confinement. These results suggest the core impurity contamination associated with ICRF heating is dominated by an increased impurity source rather than a change in impurity transport. Further, the convective cell strength was expected to scale inversely with B-field. The observed poloidal velocity (measure of convective cell strength), however, decreased less than expected. In addition, the measured maximum VRF increased and penetrated farther into the SOL at higher B-field and plasma current. Results also suggest VRF is strongly influenced by the SOL plasma parameters rather than by RF parameters. Work supported by the U.S. DoE, Office of Science, Office of Fusion Energy Sciences, User Facility Alcator C-Mod under DE-FC02-99ER54512 and DE-SC 0010720.

Excitation of slow waves in front of an ICRF antenna in a basic plasma experiment

NASA Astrophysics Data System (ADS)

Soni, Kunal; van Compernolle, Bart; Crombe, Kristel; van Eester, Dirk

2017-10-01

Recent results of ICRF experiments at the Large Plasma Device (LAPD) indicate parasitic coupling to the slow wave by the fast wave antenna. Plasma parameters in LAPD are similar to the scrape-off layer of current fusion devices. The machine has a 17 m long, 60 cm diameter magnetized plasma column with typical plasma parameters ne 1012 -1013 cm-3, Te 1 - 10 eV and B0 1000 G. It was found that coupling to the slow mode occurs when the plasma density in front of the antenna is low enough such that the lower hybrid resonance is present in the plasma. The radial density profile is tailored to allow for fast mode propagation in the high density core and slow mode propagation in the low density edge region. Measurements of the wave fields clearly show two distinct modes, one long wavelength m=1 fast wave mode in the core and a short wavelength backward propagating mode in the edge. Perpendicular wave numbers compare favorably to the predicted values. The experiment was done for varying frequencies, ω /Ωi = 25 , 6 and 1.5. Future experiments will investigate the dependence on antenna tilt angle with respect to the magnetic field, with and without Faraday screen. This work is performed at the Basic Plasma Science Facility, sponsored jointly by DOE and NSF.

TROPIX: A solar electric propulsion flight experiment

NASA Technical Reports Server (NTRS)

Hickman, J. Mark; Hillard, G. Barry; Oleson, Steven R.

1993-01-01

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

Selected OAST/OSSA space experiment activities in support of Space Station Freedom

NASA Astrophysics Data System (ADS)

Delombard, Richard

The Space Experiments Division at NASA Lewis Research Center is developing technology and science space experiments for the Office of Aeronautics and Space Technology (OAST) and the Office of Space Sciences and Applications (OSSA). Selected precursor experiments and technology development activities supporting the Space Station Freedom (SSF) are presented. The Tank Pressure Control Experiment (TPCE) is an OAST-funded cryogenic fluid dynamics experiment, the objective of which is to determine the effectiveness of jet mixing as a means of equilibrating fluid temperatures and controlling tank pressures, thereby permitting the design of lighter cryogenic tanks. The information from experiments such as this will be utilized in the design and operation of on board cryogenic storage for programs such as SSF. The Thermal Energy Storage Flight Project (TES) is an OAST-funded thermal management experiment involving phase change materials for thermal energy storage. The objective of this project is to develop and fly in-space experiments to characterize void shape and location in phase change materials used in a thermal energy storage configuration representative of an advanced solar dynamic system design. The information from experiments such as this will be utilized in the design of future solar dynamic power systems. The Solar Array Module Plasma Interaction Experiment (SAMPIE) is an OAST-funded experiment to determine the environmental effects of the low earth orbit (LEO) space plasma environment on state-of-the-art solar cell modules biased to high potentials relative to the plasma. Future spacecraft designs and structures will push the operating limits of solar cell arrays and other high voltage systems. SAMPIE will provide key information necessary for optimum module design and construction. The Vibration Isolation Technology (VIT) Advanced Technology Development effort is funded by OSSA to provide technology necessary to maintain a stable microgravity environment for sensitive payloads on board spacecraft. The proof of concept will be demonstrated by laboratory tests and in low-gravity aircraft flights. VIT is expected to be utilized by many SSF microgravity science payloads. The Space Acceleration Measurement System (SAMS) is an OSSA-funded instrument to measure the microgravity acceleration environment for OSSA payloads on the shuttle and SSF.

Selected OAST/OSSA space experiment activities in support of Space Station Freedom

NASA Technical Reports Server (NTRS)

Delombard, Richard

1992-01-01

The Space Experiments Division at NASA Lewis Research Center is developing technology and science space experiments for the Office of Aeronautics and Space Technology (OAST) and the Office of Space Sciences and Applications (OSSA). Selected precursor experiments and technology development activities supporting the Space Station Freedom (SSF) are presented. The Tank Pressure Control Experiment (TPCE) is an OAST-funded cryogenic fluid dynamics experiment, the objective of which is to determine the effectiveness of jet mixing as a means of equilibrating fluid temperatures and controlling tank pressures, thereby permitting the design of lighter cryogenic tanks. The information from experiments such as this will be utilized in the design and operation of on board cryogenic storage for programs such as SSF. The Thermal Energy Storage Flight Project (TES) is an OAST-funded thermal management experiment involving phase change materials for thermal energy storage. The objective of this project is to develop and fly in-space experiments to characterize void shape and location in phase change materials used in a thermal energy storage configuration representative of an advanced solar dynamic system design. The information from experiments such as this will be utilized in the design of future solar dynamic power systems. The Solar Array Module Plasma Interaction Experiment (SAMPIE) is an OAST-funded experiment to determine the environmental effects of the low earth orbit (LEO) space plasma environment on state-of-the-art solar cell modules biased to high potentials relative to the plasma. Future spacecraft designs and structures will push the operating limits of solar cell arrays and other high voltage systems. SAMPIE will provide key information necessary for optimum module design and construction. The Vibration Isolation Technology (VIT) Advanced Technology Development effort is funded by OSSA to provide technology necessary to maintain a stable microgravity environment for sensitive payloads on board spacecraft. The proof of concept will be demonstrated by laboratory tests and in low-gravity aircraft flights. VIT is expected to be utilized by many SSF microgravity science payloads. The Space Acceleration Measurement System (SAMS) is an OSSA-funded instrument to measure the microgravity acceleration environment for OSSA payloads on the shuttle and SSF.

Study of energetic particle dynamics in Harbin Dipole eXperiment (HDX) on Space Plasma Environment Research Facility (SPERF)

NASA Astrophysics Data System (ADS)

Zhibin, W.; Xiao, Q.; Wang, X.; Xiao, C.; Zheng, J.; E, P.; Ji, H.; Ding, W.; Lu, Q.; Ren, Y.; Mao, A.

2015-12-01

Zhibin Wang1, Qingmei Xiao1, Xiaogang Wang1, Chijie Xiao2, Jinxing Zheng3, Peng E1, Hantao Ji1,5, Weixing Ding4, Quaming Lu6, Y. Ren1,5, Aohua Mao11 Laboratory for Space Environment and Physical Sciences, Harbin Institute of Technology, Harbin, China 150001 2 State Key Lab of Nuclear Physics & Technology, and School of Physics, Peking University, Beijing, China 100871 3ASIPP, Hefei, China, 230031 4University of California at Los Angeles, Los Angeles, CA, 90095 5Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 6University of Science and Technology of China, Hefei, China, 230026 A new terrella device for laboratory studies of space physics relevant to the inner magnetospheric plasmas, Harbin Dipole eXperiment (HDX), is scheduled to be built at Harbin Institute of Technology (HIT), China. HDX is one of two essential parts of Space Plasma Environment Research Facility (SPERF), which is a major national research facility for space physics studies. HDX is designed to provide a laboratory experimental platform to reproduce the earth's magnetospheric structure for investigations on the mechanism of acceleration/loss and wave-particle interaction of energetic particles in radiation belt, and on the influence of magnetic storms on the inner magnetosphere. It can be operated together with Harbin Reconnection eXperiment (HRX), which is another part of SPERF, to study the fundamental processes during interactions between solar wind and Earth's magnetosphere. In this presentation, the scientific goals and experimental plans for HDX, together with the means applied to generate the plasma with desired parameters, including multiple plasma sources and different kinds of coils with specific functions, as well as advanced diagnostics designed to be equipped to the facility for multi-functions, are reviewed. Three typical scenarios of HDX with operations of various coils and plasma sources to study specific physical processes in space plasmas will also be presented.

Spacelab Science Results Study. Volume 2; Microgravity Science

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Editor); Lundquist, C. A. (Editor); Tandberg-Hanssen, E. (Editor); Horwitz, J. L. (Editor); Germany, G. A. (Editor); Cruise, J. F. (Editor); Lewis, M. L. (Editor); Murphy, K. L. (Editor)

1999-01-01

Beginning with OSTA-1 in November 1981, and ending with Neurolab n March 1998, thirty-six shuttle missions are considered Spacelab missions because they carried various Spacelab components such as the Spacelab module, the pallet, the Instrument Pointing System (IPS), or the MPESS (Mission Peculiar Experiment Support Structure). The experiments carried out during these flights included astrophysics, solar physics, plasma physics, atmospheric science, Earth observations, and a wide range of microgravity experiments in life sciences, biotechnology, materials science, and fluid physics which includes combustion and critical point phenomena. In all, some 764 experiments were conducted by investigators from the United States, Europe, and Japan. These experiments resulted in several thousand papers published in refereed journals, and thousands more in conference proceedings, chapters in books, and other publications. The purpose of this Spacelab Science Results Study is to document the contributions made in each of the major research areas by giving a brief synopsis of the more significant experiments and an extensive list of the publications that were produced. We have also endeavored to show how these results impacted the existing body of knowledge, where they have spawned new fields, and, if appropriate, where the knowledge they produced has been applied.

Progress towards experimental realization of extreme-velocity flow-dominated magnetized plasmas

NASA Astrophysics Data System (ADS)

Weber, T. E.; Adams, C. S.; Welch, D. R.; Kagan, G.; Bean, I. A.; Henderson, B. R.; Klim, A. J.

2017-10-01

Interactions of flow-dominated plasmas with other plasmas, neutral gases, magnetic fields, solids etc., take place with sufficient velocity that kinetic energy dominates the dynamics of the interaction (as opposed to magnetic or thermal energy, which dominates in most laboratory plasma experiments). Building upon progress made by the Magnetized Shock Experiment (MSX) at LANL, we are developing the experimental and modeling capability to increase our ultimate attainable plasma velocities well in excess of 1000 km/s. Ongoing work includes designing new pulsed power switches, triggering, and inductive adder topologies; development of novel high-speed optical diagnostics; and exploration of new numerical techniques to specifically model the unique physics of translating/stagnating flow-dominated plasmas. Furthering our understanding of the physical mechanisms of energy conversion from kinetic to other forms, such as thermal energy, non-thermal tails/accelerated populations, enhanced magnetic fields, and radiation (both continuum and line), has wide-ranging significance in basic plasma science, astrophysics, and plasma technology applications such as inertial confinement fusion and intense radiation sources. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration. LA-UR-17-25786.

The Effect of New Experimental System Design Related to the Plasma State on Achievement of Candidate Elementary Science Teachers

ERIC Educational Resources Information Center

Korkmaz, S. D.; Aybek, E. C.; Pat, S.

2015-01-01

The educational objectives related to the plasma state of matter, which comprises more than 90% of our universe, are located in the "properties of substances" unit in the 9th grade high school physics course curriculum. If there are physical and technical limitations while performing an experiment, the use of different techniques is…

Hydrodynamic instabilities at an oblique interface: Experiments and Simulations

NASA Astrophysics Data System (ADS)

Douglas-Mann, E.; Fiedler Kawaguchi, C.; Trantham, M. A.; Malamud, G.; Wan, W. C.; Klein, S. R.; Kuranz, C. C.

2017-10-01

Hydrodynamic instabilities are important phenomena that occur in high-energy-density systems, such as astrophysical systems and inertial confinement fusion experiments, where pressure, density, and velocity gradients are present. Using a 30 ns laser pulse from the Omega EP laser system, a steady shock wave is driven into a target. A Spherical Crystal Imager provides high-resolution x-ray radiographs to study the evolution of complex hydrodynamic structures. This experiment has a light-to-heavy interface at an oblique angle with a precision-machined perturbation. The incident shock wave deposits shear and vorticity at the interface causing the perturbation to grow via Richtmyer-Meshkov and Kelvin-Helmholtz processes. We present results from analysis of radiographic data and hydrodynamics simulations showing the evolution of the shock and unstable structure. This work is supported by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956 and the National Science Foundation through the Basic Plasma Science and Engineering program and LILAC.

New Outreach Initiatives at the Princeton Plasma Physics Laboratory

NASA Astrophysics Data System (ADS)

Zwicker, Andrew; Dominguez, Arturo; Greco, Shannon; Ortiz, Deedee; Delooper, John

2015-11-01

In FY15, PPPL concentrated its efforts on a portfolio of outreach activities centered around plasma science and fusion energy that have the potential to reach a large audience and have a significant and measurable impact. The overall goal of these outreach activities is to expose the public (within New Jersey, the US and the world) to the Department of Energy's scientific endeavors and specifically to PPPL's research regarding fusion and plasma science. The projects include several new activities along with upgrades to existing ones. The new activities include the development of outreach demos for the plasma physics community and the upgrade of the Internet Plasma Physics Experience (IPPEX). Our first plasma demo is a low cost DC glow discharge, suitable for tours as well as for student laboratories (plasma breakdown, spectroscopy, probes). This has been field tested in a variety of classes and events. The upgrade to the IPPEX web site includes a new template and a new interactive virtual tokamak. Future work on IPPEX will provide users limited access to data from NSTX-U. Finally, our Young Women's Conference was expanded and improved. These and other new outreach activities will be presented.

ICPP: Introduction to Dusty Plasma Physics

NASA Astrophysics Data System (ADS)

Kant Shukla, Padma

2000-10-01

Two omnipresent ingredients of the Universe are plasmas and charged dust. The interplay between these two has opened up a new and fascinating research area, that of dusty plasmas, which are ubiquitous in in different parts of our solar system, namely planetary rings, circumsolar dust rings, interplanetary medium, cometary comae and tails, interstellar molecular clouds, etc. Dusty plasmas also occur in noctilucent clouds in the arctic troposphere and mesosphere, cloud-to-ground lightening in thunderstorms containing smoke-contaminated air over the US, in the flame of humble candle, as well as in microelectronics and in low-temperature laboratory discharges. In the latter, charged dust grains are strongly correlated. Dusty plasma physics has appeared as one of the most rapidly growing field of science, besides the field of the Bose-Einstein condensate, as demonstrated by the number of published papers in scientific journals and conference proceedings. In fact, it is a truly interdisciplinary science because it has many potential applications in astrophysics (viz. in understanding the formation of dust clusters and structures, instabilities of interstellar molecular clouds and star formation, decoupling of magnetic fields from plasmas, etc.) as well as in the planetary magnetospheres of our solar system [viz. the Saturn (particularly, the physics of spokes and braids in B and F rings), Jupiter, Uranus, Neptune, and Mars] and in strongly coupled laboratory dusty plasmas. Since dusty plasma system involves the charging and the dynamics of extremely massive charged dust particulates, it can be characterized as a complex plasma system with new physics insights. In this talk, I shall describe the basic physics of dusty plasmas and present the status of numerous collective processes that are relevant to space research and laboratory experiments. The focus will be on theoretical and experimental observations of novel waves and instabilities, various forces, and some nonlinear structures (such as dust ion-acoustic shocks, Mach cones, dust voids, vortices, etc). The latter are typical in astrophysical settings and in microgravity experiments. It appears that collective processes in a complex dusty plasma would have excellent future perspectives in the twenty first century, because they have not only potential applications in interplanetary space environments, or in understanding the physics of our universe, but also in advancing our scientific knowledge in multi-disciplinary areas of science.

Voyager backgrounder

NASA Technical Reports Server (NTRS)

1981-01-01

The Voyager spacecraft and experiments are described. The spacecraft description includes the structure and configuration, communications systems, power supplies, computer command subsystems, and the science platform. The experiments discussed are investigations of cosmic rays, low-energy charged particles, magnetic fields, and plasma waves, along with studies in radio astronomy photopolarimetry. The tracking and data acquisition procedures for the missions are presented.

The PLX- α project: demonstrating the viability of spherically imploding plasma liners as an MIF driver

NASA Astrophysics Data System (ADS)

Hsu, S. C.; Witherspoon, F. D.; Cassibry, J. T.; Gilmore, M.; Samulyak, R.; Stoltz, P.; the PLX-α Team

2015-11-01

Under ARPA-E's ALPHA program, the Plasma Liner Experiment-ALPHA (PLX- α) project aims to demonstrate the viability and scalability of spherically imploding plasma liners as a standoff, high-implosion-velocity magneto-inertial-fusion (MIF) driver that is potentially compatible with both low- and high- β targets. The project has three major objectives: (a) advancing existing contoured-gap coaxial-gun technology to achieve higher operational reliability/precision and better control/reproducibility of plasma-jet properties and profiles; (2) conducting ~ π / 2 -solid-angle plasma-liner experiments with 9 guns to demonstrate (along with extrapolations from modeling) that the jet-merging process leads to Mach-number degradation and liner uniformity that are acceptable for MIF; and (3) conducting 4 π experiments with up to 60 guns to demonstrate the formation of an imploding spherical plasma liner for the first time, and to provide empirical ram-pressure and uniformity scaling data for benchmarking our codes and informing us whether the scalings justify further development beyond ALPHA. This talk will provide an overview of the PLX- α project as well as key research results to date. Supported by ARPA-E's ALPHA program; original PLX construction supported by DOE Fusion Energy Sciences.

Spacelab Science Results Study. Volume 3; Microgravity Science

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Editor); Lewis, Marian L. (Editor); Murphy, Karen L. (Compiler)

1999-01-01

Beginning with OSTA-1 in November 1981, and ending with Neurolab in March 1998, thirty-six shuttle missions are considered Spacelab missions because they carried various Spacelab components such as the Spacelab module, the pallet, the Instrument Pointing System (IPS), or the MPESS. The experiments carried out during these flights included astrophysics, solar physics, plasma physics, atmospheric science, Earth observations, and a wide range of microgravity experiments in life sciences, biotechnology, materials science, and fluid physics which includes combustion and critical point phenomena. In all, some 764 experiments were conducted by investigators from the United States, Europe, and Japan. These experiments resulted in several thousand papers published in refereed journals, and thousands more in conference proceedings, chapters in books, and other publications. The purpose of this Spacelab Science Results Study is to document the contributions made in each of the major research areas by giving a brief synopsis of the more significant experiments and an extensive list of the publications that were produced. We have also endeavored to show how these results impacted the existing body of knowledge, where they have spawned new fields, and, if appropriate, where the knowledge they produced has been applied.

Freak waves in negative-ion plasmas: an experiment revisited

NASA Astrophysics Data System (ADS)

Kourakis, Ioannis; Elkamash, Ibrahem; Reville, Brian

2016-10-01

Extreme events in the form of rogue waves (freak waves) occur widely in the open sea. These are space- and time-localised excitations, which appear unexpectedly and are characterised by a significant amplitude. Beyond ocean dynamics, the mechanisms underlying rogue wave formation are now being investigated in various physical contexts, including materials science, nonlinear optics and plasma physics, to mention but a few. We have undertaken an investigation, from first principles, of the occurrence of rogue waves associated with the propagation of electrostatic wavepackets in plasmas. Motivated by recent experimental considerations involving freak waves in negative-ion plasmas (NIP), we have addresed the occurrence of freak waves in NIP from first principles. An extended range of plasma parameter values was identified, where freak wave formation is possible, in terms of relevant plasma parameters. Our results extend -and partly contradict- the underlying assumptions in the interpretation of the aforementioned experiment, where a critical plasma configuration was considered and a Gardner equation approach was adopted. This work was supported from CPP/QUB funding. One of us (I. Elkamash) acknowledges financial support by an Egyptian Government fellowship.

Surface-Plasma Interaction on the Moon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horanyi, M.; Wang, X.; Robertson, S.

2008-09-07

The electrostatic levitation and transport of lunar dust remains a controversial science issue since the Apollo era. As a function of time and location, the lunar surface is exposed to solar wind plasma, UV radiation, and/or the plasma environment of our magnetosphere. Dust grains on the lunar surface emit and absorb plasma particles and are exposed to solar UV photons. There are several in situ and remote sensing observations that indicate that dusty plasma processes are responsible for the mobilization and transport of lunar soil. We briefly discuss the existing observations, and report on a series of experiments that addressmore » some of the most relevant processes acting on dusty surfaces exposed to plasmas and UV radiation.« less

The low energy plasma in the Uranian magnetosphere

NASA Technical Reports Server (NTRS)

Mcnutt, R. L., Jr.; Belcher, J.; Bridge, H.; Lazarus, A. J.; Richardson, J.; Sands, M.; Bagenal, F.; Eviatar, A.; Goertz, C.; Ogilvie, K.

1987-01-01

The Plasma Science experiment on Voyager 2 detected a magnetosphere filled with a tenuous plasma, rotating with the planet. Temperatures of the plasma, composed of protons and electrons, ranged from 10 eV to about 1 keV. The sources of these protons and electrons are probably the ionosphere of Uranus or the extended neutral hydrogen cloud surrounding the planet. As at earth, Jupiter, and Saturn, there is an extended magnetotail with a central plasma sheet. Although similar in global structure to the magnetospheres of these planets, the large angle between the rotation and magnetic axes of the planet and the orientation of the rotation axis with respect to the solar wind flow make the Uranian magnetosphere unique.

The HelCat dual-source plasma device.

PubMed

Lynn, Alan G; Gilmore, Mark; Watts, Christopher; Herrea, Janis; Kelly, Ralph; Will, Steve; Xie, Shuangwei; Yan, Lincan; Zhang, Yue

2009-10-01

The HelCat (Helicon-Cathode) device has been constructed to support a broad range of basic plasma science experiments relevant to the areas of solar physics, laboratory astrophysics, plasma nonlinear dynamics, and turbulence. These research topics require a relatively large plasma source capable of operating over a broad region of parameter space with a plasma duration up to at least several milliseconds. To achieve these parameters a novel dual-source system was developed utilizing both helicon and thermionic cathode sources. Plasma parameters of n(e) approximately 0.5-50 x 10(18) m(-3) and T(e) approximately 3-12 eV allow access to a wide range of collisionalities important to the research. The HelCat device and initial characterization of plasma behavior during dual-source operation are described.

Message From the Editor for Contributions to the 2012 Real Time Conference Issue of TNS

NASA Astrophysics Data System (ADS)

Schmeling, Sascha Marc

2013-10-01

The papers in this special issue were originally presented at the 18th IEEE-NPSS Real Time Conference (RT2012) on Computing Applications in Nuclear and Plasma Sciences, held in Berkeley, California, USA, in June 2012. These contributions come from a broad range of fields of application, including Astrophysics, Medical Imaging, Nuclear and Plasma Physics, Particle Accelerators, and Particle Physics Experiments.

ZAPP shot summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loisel, Guillaume Pascal

This was the second Z Astrophysical Plasma Properties (ZAPP) fundamental science shot series of 2015. ZAPP experiments measure fundamental properties of atoms in plasmas to solve the following important astrophysical puzzles: Why can’t we accurately model the opacity of Fe at the convection zone boundary in the Sun? How accurate are the photoionization models used to interpret data from xray satellite observations? and Why doesn’t spectral fitting provide the correct properties for White Dwarfs?

Experimental study of the performance of a very small repetitive plasma focus device in different working conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goudarzi, S., E-mail: sgoudarzi@aeoi.org.ir; Babaee, H.; Esmaeli, A.

SORENA-1 is a very small repetitive Mather-type plasma focus device (20 J) that can operate at frequencies up to 1 Hz. This device has been designed and constructed in the Plasma and Nuclear Fusion Research School of the Nuclear Science and Technology Research Institute of Iran. In this article, the structure of SORENA-1 is described and results of experiments with Ar, Ne, and D{sub 2} working gases at several discharge voltages and initial pressures are presented and analyzed.

Experimental study of the performance of a very small repetitive plasma focus device in different working conditions

NASA Astrophysics Data System (ADS)

Goudarzi, S.; Babaee, H.; Esmaeli, A.; Nasiri, A.

2017-01-01

SORENA-1 is a very small repetitive Mather-type plasma focus device (20 J) that can operate at frequencies up to 1 Hz. This device has been designed and constructed in the Plasma and Nuclear Fusion Research School of the Nuclear Science and Technology Research Institute of Iran. In this article, the structure of SORENA-1 is described and results of experiments with Ar, Ne, and D2 working gases at several discharge voltages and initial pressures are presented and analyzed.

GITR Simulation of Helium Exposed Tungsten Erosion and Redistribution in PISCES-A

NASA Astrophysics Data System (ADS)

Younkin, T. R.; Green, D. L.; Doerner, R. P.; Nishijima, D.; Drobny, J.; Canik, J. M.; Wirth, B. D.

2017-10-01

The extreme heat, charged particle, and neutron flux / fluence to plasma facing materials in magnetically confined fusion devices has motivated research to understand, predict, and mitigate the associated detrimental effects. Of relevance to the ITER divertor is the helium interaction with the tungsten divertor, the resulting erosion and migration of impurities. The linear plasma device PISCES A has performed dedicated experiments for high (4x10-22 m-2s-1) and low (4x10-21 m-2s-1) flux, 250 eV He exposed tungsten targets to assess the net and gross erosion of tungsten and volumetric transport. The temperature of the target was held between 400 and 600 degrees C. We present results of the erosion / migration / re-deposition of W during the experiment from the GITR (Global Impurity Transport) code coupled to materials response models. In particular, the modeled and experimental W I emission spectroscopy data for the 429.4 nm wavelength and net erosion through target and collector mass difference measurements are compared. Overall, the predictions are in good agreement with experiments. This material is supported by the US DOE, Office of Science, Office of Fusion Energy Sciences and Office of Advanced Scientific Computing Research through the SciDAC program on Plasma-Surface Interactions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koepke, Mark

Collaborative research between WVU and PPPL was carried out at WVU for the purpose of incorporating the sophisticated diagnostic technique known as laser-induced fluorescence (LIF) in the Paul-Trap Simulation Experiment (PTSX) at PPPL. WVU assembled a LIF system at WVU, transported it to PPPL, helped make LIF experiments on the PTSX device, participated in PTSX science, and trained PPPL staff in LIF techniques. In summary, WVU refurbished a non-operational LIF system being loaned from University of Maryland to PPPL and, by doing so, provided PPPL with additional diagnostic capability for its PTSX device and other General Plasma Science experiments. WVUmore » students, staff, and faculty will visit PPPL to collaborate on PTSX experiments in the future.« less

Response function of modulated grid Faraday cup plasma instruments

NASA Technical Reports Server (NTRS)

Barnett, A.; Olbert, S.

1986-01-01

Modulated grid Faraday cup plasma analyzers are a very useful tool for making in situ measurements of space plasmas. One of their great attributes is that their simplicity permits their angular response function to be calculated theoretically. An expression is derived for this response function by computing the trajectories of the charged particles inside the cup. The Voyager plasma science experiment is used as a specific example. Two approximations to the rigorous response function useful for data analysis are discussed. Multisensor analysis of solar wind data indicates that the formulas represent the true cup response function for all angles of incidence with a maximum error of only a few percent.

Uranus science planning. [considering Mariner Jupiter-Uranus mission

NASA Technical Reports Server (NTRS)

Moore, J.

1974-01-01

Recommendations for a 1979 Mariner Jupiter-Uranus mission are discussed with the possibility of launching the first outer planet atmospheric entry probe. Measurement categories considered for the mission include conducting imaging experiments, observations in both the IR and UV spectral range, experiments associated with magnetic fields, plasma, charged particles, and S- and X-band occultation measurements.

Plasma Physics at the National Science Foundation

NASA Astrophysics Data System (ADS)

Lukin, Vyacheslav

2017-10-01

The Town Meeting on Plasma Physics at the National Science Foundation will provide an opportunity for Q&A about the variety of NSF programs and solicitations relevant to a broad cross-section of the academic plasma science community, from graduating college seniors to senior leaders in the field, and from plasma astrophysics to basic physics to plasma engineering communities. We will discuss recent NSF-hosted events, research awards, and multi-agency partnerships aimed at enabling the progress of science in plasma science and engineering. Future outlook for plasma physics and broader plasma science support at NSF, with an emphasis on how you can help NSF to help the community, will be speculated upon within the uncertainty of the federal budgeting process.

ALPhA Laboratory Immersion in Plasma Physics

NASA Astrophysics Data System (ADS)

Dominguez, A.; Zwicker, A.; Williams, J. D.

2016-10-01

According to the FESAC, as recently as 2014 there were a total of just 14 universities offering strong curricula in MFE sciences. Similarly, it was reported that 8 and 19 universities offer strong HEDPL and Discovery Plasma programs respectively. At the undergraduate level, there is also a lack of plasma physics in the curricula. This, regardless of its rich insights into the core subfields of physics, i.e., classical mechanics, electrodynamics, statistical mechanics and quantum phenomena. The coauthors have been leading a plasma physics workshop for the last 3 years directed at undergraduate physics professors and lecturers. The workshop is centered around a versatile and relatively inexpensive (< 10 k) plasma discharge experiment which lets students explore Panchen's Law, spectroscopy and Langmuir probes. The workshop is part of the Advanced Laboratory Physics Association (ALPhA) Laboratory Immersions, and its objective is for the participants to become familiar with the experiments and incorporate them into their home institution's curricula as junior labs, senior labs or independent student projects.

Growing a Science Internship One Year at a Time: Updates to the Science Undergraduate Laboratory Internship Program D. Ortiz-Arias, A. Dominguez, A. Zwicker, S. Greco

NASA Astrophysics Data System (ADS)

Ortiz, Deedee; Dominguez, Arturo; Zwicker, Andrew; Greco, Shannon

2016-10-01

Between 1993-2014, the National Undergraduate Fellowship (NUF) program, sponsored by the DOE Office of Fusion Energy Sciences, provided summer research internships for outstanding undergraduate students from around the country. Since then, the NUF program was merged into the Science Undergraduate Laboratory Internship (SULI) program, sponsored by the DOE Office of Workforce Development for Teachers and Students. While there were many similarities between the two programs, the SULI program did not include the one-week introductory course in plasma physics or the opportunity for participants to present their summer research results at this meeting. In the past two years, working with representatives from both OFES and WDTS, we have again implemented some of the most important components of the NUF program. The week-long, introductory course in plasma physics is included and streamed live- especially important since most undergraduate physics students have not taken a plasma physics course before they begin their research. Students are again able to present their research to our community, a critical component of a full research experience and plans are underway to obtain additional funding to once again include universities as eligible host sites.

Phase I Development of Neutral Beam Injector Solid-State Power System

NASA Astrophysics Data System (ADS)

Prager, James; Ziemba, Timothy; Miller, Kenneth E.; Slobodov, Ilia; Anderson, Seth

2017-10-01

Neutral beam injection (NBI) is an important tool for plasma heating, current drive and a diagnostic at fusion science experiments around the United States, including tokamaks, validation platform experiments, and privately funded fusion concepts. Currently, there are no vendors in the United States for NBI power systems. Eagle Harbor Technologies (EHT), Inc. is developing a new power system for NBI that takes advantage of the latest developments in solid-state switching. EHT has developed a resonant converter that can be scaled to the power levels required for NBI at small-scale validation platform experiments like the Lithium Tokamak Experiment. This power system can be used to modulate the NBI voltages over the course of a plasma shot, which can lead to improved control over the plasma. EHT will present initial modeling used to design this system as well as experimental data showing operation at 15 kV and 40 A for 10 ms into a test load. With support of DOE SBIR.

Fusion/Astrophysics Teacher Research Academy

NASA Astrophysics Data System (ADS)

Correll, Donald

2005-10-01

In order to engage California high school science teachers in the area of plasma physics and fusion research, LLNL's Fusion Energy Program has partnered with the UC Davis Edward Teller Education Center, ETEC (http://etec.ucdavis.edu), the Stanford University Solar Center (http://solar-center.stanford.edu) and LLNL's Science / Technology Education Program, STEP (http://education.llnl.gov). A four-level ``Fusion & Astrophysics Research Academy'' has been designed to give teachers experience in conducting research using spectroscopy with their students. Spectroscopy, and its relationship to atomic physics and electromagnetism, provides for an ideal plasma `bridge' to the CA Science Education Standards (http://www.cde.ca.gov/be/st/ss/scphysics.asp). Teachers attend multiple-day professional development workshops to explore new research activities for use in the high school science classroom. A Level I, 3-day program consists of two days where teachers learn how plasma researchers use spectrometers followed by instructions on how to use a research grade spectrometer for their own investigations. A 3rd day includes touring LLNL's SSPX (http://www.mfescience.org/sspx/) facility to see spectrometry being used to measure plasma properties. Spectrometry classroom kits are made available for loaning to participating teachers. Level I workshop results (http://education.llnl.gov/fusion&_slash;astro/) will be presented along with plans being developed for Level II (one week advanced SKA's), Level III (pre-internship), and Level IV (summer internship) research academies.

Voyager 1 examines Jupiter

NASA Technical Reports Server (NTRS)

1979-01-01

An overview of the Voyager mission to Jupiter, Saturn, and possibly Uranus is presented. Scientific instruments onboard the spacecraft are described as well as methods used for their calibration and evaluation during the cruise phase of the mission. Experiments to be performed cover the following areas: imaging science, radio science, cosmic rays, ultraviolet spectroscopy, photopolarimetry, planetary radio astronomy, magnetic fields, low-energy charged particles, plasma science, and infrared radiometry and spectroscopy. A list of the satellites of Jupiter and their diameters, distances, and periods is included.

Net current measurements and secondary electron emission characteristics of the Voyager plasma science experiment and their impact on data interpretation

NASA Technical Reports Server (NTRS)

Mcnutt, Ralph L., Jr.

1988-01-01

The Voyager Plasma Science (PLS) instrument is capable of returning integral (DC) current measurements, similar in some respects to measurements made with a Langmuir probe or a retarding potential analyzer, although there are significant differences. The integral measurements were made during a calibration sequence in the solar wind, during Cruise Science Maneuvers, and within the magnetospheres of Jupiter and Saturn by Voyager 1. After the failure of the PLS experiment following the Saturn encounter, that instrument was placed in the DC return mode returning possibly usable data from early 1981 through early 1985. The DC return measurements are difficult to interpret and are above threshold values only for relatively large fluxes; the determination of the measured current level is dependent on the operating temperature of the preamplifiers which further complicates the interpretation. Nevertheless, these measurements can be used to determine the efficiency of the suppressor grid at preventing the loss of secondary electrons off the collector plate. Some DC return measurements have been invaluable in aiding in the interpretation of some electron plasma measurements not previously understood. It is found that electron spectra can be significantly modified by the presence of second generation secondary electrons produced by either first generation secondaries or photoelectrons on the support ring of the negative high voltage modulator grid within the instrument housing.

Particle and heat flux estimates in Proto-MPEX in Helicon Mode with IR imaging

NASA Astrophysics Data System (ADS)

Showers, M. A.; Biewer, T. M.; Caughman, J. B. O.; Donovan, D. C.; Goulding, R. H.; Rapp, J.

2016-10-01

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory (ORNL) is a linear plasma device developing the plasma source concept for the Material Plasma Exposure eXperiment (MPEX), which will address plasma material interaction (PMI) science for future fusion reactors. To better understand how and where energy is being lost from the Proto-MPEX plasma during ``helicon mode'' operations, particle and heat fluxes are quantified at multiple locations along the machine length. Relevant diagnostics include infrared (IR) cameras, four double Langmuir probes (LPs), and in-vessel thermocouples (TCs). The IR cameras provide temperature measurements of Proto-MPEX's plasma-facing dump and target plates, located on either end of the machine. The change in surface temperature is measured over the duration of the plasma shot to determine the heat flux hitting the plates. The IR cameras additionally provide 2-D thermal load distribution images of these plates, highlighting Proto-MPEX plasma behaviors, such as hot spots. The LPs and TCs provide additional plasma measurements required to determine particle and heat fluxes. Quantifying axial variations in fluxes will help identify machine operating parameters that will improve Proto-MPEX's performance, increasing its PMI research capabilities. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

Vacuum System and Modeling for the Materials Plasma Exposure Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lumsdaine, Arnold; Meitner, Steve; Graves, Van

Understanding the science of plasma-material interactions (PMI) is essential for the future development of fusion facilities. The design of divertors and first walls for the next generation of long-pulse fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or a DEMO, requires significant PMI research and development. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX) is proposed, which will produce divertor relevant plasma conditions for these next generation facilities. The device will be capable of handling low activation irradiated samples and be able to remove and replace samples without breakingmore » vacuum. A Target Exchange Chamber (TEC) which can be disconnected from the high field environment in order to perform in-situ diagnostics is planned for the facility as well. The vacuum system for MPEX must be carefully designed in order to meet the requirements of the different heating systems, and to provide conditions at the target similar to those expected in a divertor. An automated coupling-decoupling (“autocoupler”) system is designed to create a high vacuum seal, and will allow the TEC to be disconnected without breaking vacuum in either the TEC or the primary plasma materials interaction chamber. This autocoupler, which can be actuated remotely in the presence of the high magnetic fields, has been designed and prototyped, and shows robustness in a variety of conditions. The vacuum system has been modeled using a simplified finite element analysis, and indicates that the design goals for the pressures in key regions of the facility are achievable.« less

Vacuum System and Modeling for the Materials Plasma Exposure Experiment

DOE PAGES

Lumsdaine, Arnold; Meitner, Steve; Graves, Van; ...

2017-08-07

Understanding the science of plasma-material interactions (PMI) is essential for the future development of fusion facilities. The design of divertors and first walls for the next generation of long-pulse fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or a DEMO, requires significant PMI research and development. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX) is proposed, which will produce divertor relevant plasma conditions for these next generation facilities. The device will be capable of handling low activation irradiated samples and be able to remove and replace samples without breakingmore » vacuum. A Target Exchange Chamber (TEC) which can be disconnected from the high field environment in order to perform in-situ diagnostics is planned for the facility as well. The vacuum system for MPEX must be carefully designed in order to meet the requirements of the different heating systems, and to provide conditions at the target similar to those expected in a divertor. An automated coupling-decoupling (“autocoupler”) system is designed to create a high vacuum seal, and will allow the TEC to be disconnected without breaking vacuum in either the TEC or the primary plasma materials interaction chamber. This autocoupler, which can be actuated remotely in the presence of the high magnetic fields, has been designed and prototyped, and shows robustness in a variety of conditions. The vacuum system has been modeled using a simplified finite element analysis, and indicates that the design goals for the pressures in key regions of the facility are achievable.« less

Physics of neutral gas jet interaction with magnetized plasmas

NASA Astrophysics Data System (ADS)

Wang, Zhanhui; Xu, Xueqiao; Diamond, Patrick; Xu, Min; Duan, Xuru; Yu, Deliang; Zhou, Yulin; Shi, Yongfu; Nie, Lin; Ke, Rui; Zhong, Wulv; Shi, Zhongbing; Sun, Aiping; Li, Jiquan; Yao, Lianghua

2017-10-01

It is critical to understand the physics and transport dynamics during the plasma fuelling process. Plasma and neutral interactions involve the transfer of charge, momentum, and energy in ion-neutral and electron-neutral collisions. Thus, a seven field fluid model of neutral gas jet injection (NGJI) is obtained, which couples plasma density, heat, and momentum transport equations together with neutrals density and momentum transport equations of both molecules and atoms. Transport dynamics of plasma and neutrals are simulated for a complete range of discharge times, including steady state before NGJI, transport during NGJI, and relaxation after NGJI. With the trans-neut module of BOUT + + code, the simulations of mean profile variations and fueling depths during fueling have been benchmarked well with other codes and also validated with HL-2A experiment results. Both fast component (FC) and slow component (SC) of NGJI are simulated and validated with the HL-2A experimental measurements. The plasma blocking effect on the FC penetration is also simulated and validated well with the experiment. This work is supported by the National Natural Science Foundation of China under Grant No. 11575055.

Education Outreach at M.I.T. Plasma Science and Fusion Center

NASA Astrophysics Data System (ADS)

Rivenberg, P.; Censabella, V.

2000-10-01

At the MIT PSFC student and staff volunteers work together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PSFC holds a number of outreach activities throughout the year, including Middle and High School Outreach Days and the Mr. Magnet program. During the past year, in collaboration with the MIT Museum, the PSFC reprogrammed their C-Mod, Jr Video Game to be operated via the keyboard instead of joysticks. The game will eventually be available on the web and on disc. The PSFC maintains a Home Page on the World Wide Web, which can be reached at http://www.psfc.mit.edu.

Fast wave experiments in LAPD: RF sheaths, convective cells and density modifications

NASA Astrophysics Data System (ADS)

Carter, T. A.; van Compernolle, B.; Martin, M.; Gekelman, W.; Pribyl, P.; van Eester, D.; Crombe, K.; Perkins, R.; Lau, C.; Martin, E.; Caughman, J.; Tripathi, S. K. P.; Vincena, S.

2017-10-01

An overview is presented of recent work on ICRF physics at the Large Plasma Device (LAPD) at UCLA. The LAPD has typical plasma parameters ne 1012 -1013 cm-3, Te 1 - 10 eV and B 1000 G. A new high-power ( 150 kW) RF system and fast wave antenna have been developed for LAPD. The source runs at a frequency of 2.4 MHz, corresponding to 1 - 7fci , depending on plasma parameters. Evidence of rectified RF sheaths is seen in large increases ( 10Te) in the plasma potential on field lines connected to the antenna. The rectified potential scales linearly with antenna current. The rectified RF sheaths set up convective cells of local E × B flows, measured indirectly by potential measurements, and measured directly with Mach probes. At high antenna powers substantial modifications of the density profile were observed. The plasma density profile initially exhibits transient low frequency oscillations (10 kHz). The amplitude of the fast wave fields in the core plasma is modulated at the same low frequency, suggesting fast wave coupling is affected by the density rearrangement. Work performed at the Basic Plasma Science Facility, supported jointly by the National Science Foundation and the Department of Energy.

Spacelab Science Results Study: Executive Summary

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Editor)

1999-01-01

Beginning with OSTA-1 in November 1981, and ending with Neurolab in March 1998, thirty-six shuttle missions are considered Spacelab missions because they carried various Spacelab components such as the Spacelab module, the pallet, the Instrument Pointing System (IPS), or the MPESS. The experiments carried out during these flights included astrophysics, solar physics, plasma physics, atmospheric science, Earth observations, and a wide range of microgravity experiments in life sciences, biotechnology, materials science, and fluid physics which includes combustion and critical point phenomena. In all, some 764 experiments were conducted by investigators from the United States, Europe, and Japan. These experiments resulted in several thousand papers published In refereed journals, and thousands more in conference proceedings, chapters in books, and other publications. The purpose of this Spacelab Science Results Study is to document the contributions made in each of the major research areas by giving a brief synopsis of the more significant experiments and an extensive list of the publications that were produced. We have also endeavored to show how these results impacted the existing body of knowledge, where they have spawned new fields, and, if appropriate, where the knowledge they produced has been applied.

Initial Results of HamSCI Ham Radio 21 August 2017 Eclipse Ionospheric Experiments

NASA Astrophysics Data System (ADS)

Frissell, N. A.; Gerrard, A. J.; Vega, J. S.; Katz, J. D.; West, M. L.; Gunning, S. W.; Moses, M. L.; Miller, E. S.; Erickson, P. J.; Huba, J.; Silver, H. W.; Ceglia, F.; Smith, P.; Williams, R.; Shovkoplyas, A.; Earle, G. D.; Gerzoff, R.; Gladstone, P.; Reyer, S. E.; Ackermann, J. R.; Bern, D.; Rose, S. W.

2017-12-01

On 21 August 2017, a total solar eclipse will cause the shadow of the moon to traverse the United States from Oregon to South Carolina in just over 90 minutes. The sudden absence of sunlight due to the eclipse, especially solar UV and x-rays, provides an impulse function to the upper atmosphere that modifies the neutral dynamics, plasma concentrations, and related properties. Despite more than 60 years of research, questions remain regarding eclipse-induced ionospheric impacts. Ham radio operators' advanced technical skills and inherent interest in ionospheric science make the amateur radio community ideal for contributing to and and participating in large-scale ionospheric sounding experiments. We present initial results from three amateur radio experiments designed to study the 2017 total solar eclipse: the Solar Eclipse QSO Party (SEQP), the HF Wideband Recording Experiment, and the Eclipse Frequency Measurement Test (FMT). These experiments are coordinated by HamSCI, the Ham Radio Science Citizen Investigation, a citizen science organization that connects the amateur radio community to the professional space science research community for mutual benefit.

Participation in the definition, conduct, and analysis of particle accelerator experiments for the first Spacelab Mission

NASA Technical Reports Server (NTRS)

Burch, J. L.

1994-01-01

The Space Experiments with Particle Accelerators (SEPAC) is a joint endeavor between NASA and the Institute of Space and Aeronautical Sciences (ISAS) in Japan. Its objectives are to use energetic electron beams to investigate beam-atmosphere interactions and beam-plasma interactions in the earth's upper atmosphere and ionosphere using the shuttle Spacelab. Two flights of SEPAC have occurred to date (Spacelab 1 on STS-9 in Nov.-Dec. 1983 and ATLAS 1 on STS-45 in Mar.-Apr. 1992). The SEPAC instrumentation is available for future missions, and the scientific results of the first two missions justify further investigations; however, at present there are no identifiable future flight opportunities. As specified in the contract, the primary purpose of this report is to review the scientific accomplishments of the ATLAS 1 SEPAC experiments, which have been documented in the published literature, with only a brief review of the earlier Spacelab 1 results. One of the main results of the Spacelab 1 SEPAC experiments was that the ejection of plasma from the magnetoplasmadynamic (MPD) arcjet was effective in maintaining vehicle charge neutralization during electron beam firings, but only for a brief period of 10 ms or so. Therefore, a xenon plasma contactor, which can provide continuous vehicle charge neutralization, was developed for the ATLAS 1 SEPAC experiments. Because of the successful operation of the plasma contactor on ATLAS 1, it was possible to perform experiments on beam-plasma interactions and beam-atmosphere interactions at the highest beam power levels of SEPAC. In addition, the ability of the plasma contactor to eject neutral xenon led to a successful experiment on the critical ionization velocity (CIV) phenomena on ATLAS 1.

National Spherical Torus Experiment (NSTX) and Planned Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Yueng Kay Martin; Ono, M.; Kaye, S.

1998-01-01

The U.S. fusion energy sciences program began in 1996 to increase emphasis on confinement concept innovation. The NSTX is being built at PPPL as a national fusion science research facility in response to this emphasis. NSTX is to test fusion science principles of the Spherical Torus (ST) plasmas, which include: (1) High plasma pressure in low magnetic field for high fusion power density, (2) Good energy confinement is a small-size plasma, (3) Nearly fully self-driven (bootstrap) plasma current, (4) Dispersed heat and particle fluxes, and (5) Plasma startup without complicated in board solenoid magnet. These properties of the ST plasma,more » if verified, would lead to possible future fusion devices of high fusion performance, small size, feasible power handling, and improved economy. The design of NSTX is depicted in a figure. The vessel will be covered fully with graphite tiles and can be baked to 350 C. Other wall condition techniques are also planned. The NSTX facilty extensively utilizes the equipment at PPPL and other reasearch institutions in collaboration. These include 6-MW High Harmonic Fast Wave (HHFW) power at {approx}30 MHz for 5 s, which will be the primary heating and current drive system following the first plasma planned for April 1999, and small ECH systems to assist breakdown for initiation. A plethora of diagnostics from TFTR and collaborators are planned. A NBI system from TFTR capable of delivering 5 MW at 80 keV for 5 s, and more powerful ECH systems are also planned for installation in 2000. The baseline plan for diagnostics systems are laid out in a figure and include: (1) Rogowski coils to measure total plasma and halo curents.« less

Atmospheric, Magnetospheric and Plasmas in space (AMPS) spacelab payload definition study. Volume 2: Mission support requirements document

NASA Technical Reports Server (NTRS)

1976-01-01

The science objectives, the experiment and instrument requirements, and the total ground and mission related requirements to be implemented by GSFC and other NASA centers for each AMPS/Labcraft mission are defined.

Measuring the Silver Composition of Nanocolloids by Inductively Coupled Plasma-Optical Emission Spectroscopy: A Laboratory Experiment for Chemistry and Engineering Students

ERIC Educational Resources Information Center

Brittle, Seth W.; Baker, Joshua D.; Dorney, Kevin M.; Dagher, Jessica M.; Ebrahimian, Tala; Higgins, Steven R.; Pavel Sizemore, Ioana E.

2015-01-01

The increased worldwide exploitation of nanomaterials has reinforced the importance of introducing nanoscale aspects into the undergraduate and graduate curriculum. To meet this need, a novel nano-laboratory module was developed and successfully performed by science and engineering students. The main goal of the experiment was to accurately…

Plasma Sources for Medical Applications - A Comparison of Spot Like Plasmas and Large Area Plasmas

NASA Astrophysics Data System (ADS)

Weltmann, Klaus-Dieter

2015-09-01

Plasma applications in life science are currently emerging worldwide. Whereas today's commercially available plasma surgical technologies such as argon plasma coagulation (APC) or ablation are mainly based on lethal plasma effects on living systems, the newly emerging therapeutic applications will be based on selective, at least partially non-lethal, possibly stimulating plasma effects on living cells and tissue. Promising results could be obtained by different research groups worldwide revealing a huge potential for the application of low temperature atmospheric pressure plasma in fields such as tissue engineering, healing of chronic wounds, treatment of skin diseases, tumor treatment based on specific induction of apoptotic processes, inhibition of biofilm formation and direct action on biofilms or treatment of dental diseases. The development of suitable and reliable plasma sources for the different therapies requires an in-depth knowledge of their physics, chemistry and parameters. Therefore much basic research still needs to be conducted to minimize risk and to provide a scientific fundament for new plasma-based medical therapies. It is essential to perform a comprehensive assessment of physical and biological experiments to clarify minimum standards for plasma sources for applications in life science and for comparison of different sources. One result is the DIN-SPEC 91315, which is now open for further improvements. This contribution intends to give an overview on the status of commercial cold plasma sources as well as cold plasma sources still under development for medical use. It will discuss needs, prospects and approaches for the characterization of plasmas from different points of view. Regarding the manageability in everyday medical life, atmospheric pressure plasma jets (APPJ) and dielectric barrier discharges (DBD) are of special interest. A comprehensive risk-benefit assessment including the state of the art of commercial sources for medical use will be discussed.

Kinetic and radiation-hydrodynamic modeling of x-ray heating in laboratory photoionized plasmas

NASA Astrophysics Data System (ADS)

Mancini, Roberto

2017-06-01

In experiments performed at the Z facility of Sandia National Laboratories a cm-scale cell filled with neon gas was driven by the burst of broadband x-rays emitted at the collapse of a wire-array z-pinch turning the gas into a photoionized plasma. Transmission spectroscopy of a narrowband portion of the x-ray flux was used to diagnose the plasma. The data show a highly-ionized neon plasma with a rich line absorption spectrum that permits the extraction of the ionization distribution among Be-, Li-, He- and H-like ions. Analysis of the spectra produced atomic ground and low excited state areal densities in these ions, and from the ratio of first-excited to ground state populations in Li-like neon a temperature of 19±4eV was extracted to characterize the x-ray heating of the plasma. To interpret this observation, we have performed data-constrained view-factor calculations of the spectral distribution of the x-ray drive, self-consistent modeling of electron and atomic kinetics, and radiation-hydrodynamic simulations. For the conditions of the experiment, the electron distribution thermalizes quickly, has a negligible high-energy tail, and is very well approximated by a single Maxwellian distribution. Radiation-hydrodynamic simulations with either LTE or NLTE (i.e. non-equilibrium) atomic physics provide a more complete modeling of the experiment. We found that in order to compute electron temperatures consistent with observation inline non-equilibrium collisional-radiative neon atomic kinetics needs to be taken into account. We discuss the details of LTE and NLTE simulations, and the impact of atomic physics on the radiation heating and cooling rates that determine the plasma temperature. This work was sponsored in part by DOE Office of Science Grant DE-SC0014451, and the Z Facility Fundamental Science Program of SNL.

Hypervelocity Dust Impacts in Space and the Laboratory

NASA Astrophysics Data System (ADS)

Horanyi, Mihaly; Colorado CenterLunar Dust; Atmospheric Studies (CCLDAS) Team

2013-10-01

Interplanetary dust particles continually bombard all objects in the solar system, leading to the excavation of material from the target surfaces, the production of secondary ejecta particles, plasma, neutral gas, and electromagnetic radiation. These processes are of interest to basic plasma science, planetary and space physics, and engineering to protect humans and instruments against impact damages. The Colorado Center for Lunar Dust and Atmospheric Studies (CCLDAS) has recently completed a 3 MV dust accelerator, and this talk will summarize our initial science results. The 3 MV Pelletron contains a dust source, feeding positively charged micron and sub-micron sized particles into the accelerator. We will present the technical details of the facility and its capabilities, as well as the results of our initial experiments for damage assessment of optical devices, and penetration studies of thin films. We will also report on the completion of our dust impact detector, the Lunar Dust Experiment (LDEX), is expected to be flying onboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission by the time of this presentation. LDEX was tested, and calibrated at our dust accelerator. We will close by offering the opportunity to use this facility by the planetary, space and plasma physics communities.

Plasma-surface interaction in the context of ITER.

PubMed

Kleyn, A W; Lopes Cardozo, N J; Samm, U

2006-04-21

The decreasing availability of energy and concern about climate change necessitate the development of novel sustainable energy sources. Fusion energy is such a source. Although it will take several decades to develop it into routinely operated power sources, the ultimate potential of fusion energy is very high and badly needed. A major step forward in the development of fusion energy is the decision to construct the experimental test reactor ITER. ITER will stimulate research in many areas of science. This article serves as an introduction to some of those areas. In particular, we discuss research opportunities in the context of plasma-surface interactions. The fusion plasma, with a typical temperature of 10 keV, has to be brought into contact with a physical wall in order to remove the helium produced and drain the excess energy in the fusion plasma. The fusion plasma is far too hot to be brought into direct contact with a physical wall. It would degrade the wall and the debris from the wall would extinguish the plasma. Therefore, schemes are developed to cool down the plasma locally before it impacts on a physical surface. The resulting plasma-surface interaction in ITER is facing several challenges including surface erosion, material redeposition and tritium retention. In this article we introduce how the plasma-surface interaction relevant for ITER can be studied in small scale experiments. The various requirements for such experiments are introduced and examples of present and future experiments will be given. The emphasis in this article will be on the experimental studies of plasma-surface interactions.

All things White Dwarf: The State of Stellar Forensics at the University of Texas and Sandia National Laboratories

NASA Astrophysics Data System (ADS)

Winget, Donald

2011-10-01

Astronomy has always been considered an observational science, in contrast with other experimental sciences like physics, chemistry, biology, and geology. This is because it has not been possible to perform experiments on the objects we observe. This situation has changed in a way that is transformational. We are now able to make macroscopic bits of star stuff in the lab: plasmas created under conditions that are the same as the plasmas in stars. Although laboratory astrophysics has long been an important part of astronomical research, what has changed is the ability to produce large enough chunks of a star that we can make measurements and perform experiments. In this way, astronomy joins her sister sciences in becoming an experimental science as well as an observational one. I will describe how this came about, the technology behind it, and the results of recent laboratory experiments. Most importantly, we will discuss how this will change our understanding of the universe and its contents. This work will shed new light on our recent discoveries involving McDonald Observatory: planets around white dwarf stars, massive carbon/oxygen variable white dwarf stars, and white dwarf-white dwarf binaries -- including one detached double eclipsing system with an orbital period of 12 minutes. We should measure the rate of change of the orbital period in this system within a year and we expect it to be the highest S/N source of gravitational radiation, easily detectable with LISA or similar approaches.

Atmospheric science facility pallet-only mode space transportation system payload (feasibility study), Volume 1

NASA Technical Reports Server (NTRS)

1975-01-01

The economic and technical feasibility is assessed of employing a pallet-only mode for conducting Atmospheric Magnetospheric Plasmas-in-Space experiments. A baseline design incorporating the experiment and instrument descriptions is developed. The prime instruments are packaged into four pallets in a physical and functional manner compatible with the Space Transportation System capabilities and/or constraints and an orbiter seven-day mission timeline. Operational compatibility is verified between the orbiter/payload and supporting facilities. The development status and the schedule requirements applicable to the Atmospheric Science Facility mission are identified. Conclusions and recommendations are presented and discussed.

Modeling Laboratory Astrophysics Experiments using the CRASH code

NASA Astrophysics Data System (ADS)

Trantham, Matthew; Drake, R. P.; Grosskopf, Michael; Bauerle, Matthew; Kruanz, Carolyn; Keiter, Paul; Malamud, Guy; Crash Team

2013-10-01

The understanding of high energy density systems can be advanced by laboratory astrophysics experiments. Computer simulations can assist in the design and analysis of these experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport and electron heat conduction. This poster/talk will demonstrate some of the experiments the CRASH code has helped design or analyze including: Radiative shocks experiments, Kelvin-Helmholtz experiments, Rayleigh-Taylor experiments, plasma sheet, and interacting jets experiments. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via grant DEFC52- 08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-NA0000850.

Laboratory Experiments to Simulate and Investigate the Physics Underlying the Dynamics of Merging Solar Corona Structures

DTIC Science & Technology

2016-06-05

have attended and made presen- tations at the annual APS Division of Plasma Physics Meeting, the bi-annual High Energy Laboratory Astrophysics meeting...the AFOSR Space Science Pro- gram Review, the SHINE solar physics meeting, the International Astrophysics Conference, and the workshop “Complex plasma...tor k and Resolving Space-time Ambiguity. GR-Space Physics . submitted. Bellan, P. M., Zhai, X., Chai, K. B., & Ha, B. N. 2015. Complex astrophysical

Technical issues in the conduct of large space platform experiments in plasma physics and geoplasma sciences

NASA Technical Reports Server (NTRS)

Szuszczewicz, Edward P.

1986-01-01

Large, permanently-manned space platforms can provide exciting opportunities for discoveries in basic plasma and geoplasma sciences. The potential for these discoveries will depend very critically on the properties of the platform, its subsystems, and their abilities to fulfill a spectrum of scientific requirements. With this in mind, the planning of space station research initiatives and the development of attendant platform engineering should allow for the identification of critical science and technology issues that must be clarified far in advance of space station program implementation. An attempt is made to contribute to that process, with a perspective that looks to the development of the space station as a permanently-manned Spaceborne Ionospheric Weather Station. The development of this concept requires a synergism of science and technology which leads to several critical design issues. To explore the identification of these issues, the development of the concept of an Ionospheric Weather Station will necessarily touch upon a number of diverse areas. These areas are discussed.

State of the art in medical applications using non-thermal atmospheric pressure plasma

NASA Astrophysics Data System (ADS)

Tanaka, Hiromasa; Ishikawa, Kenji; Mizuno, Masaaki; Toyokuni, Shinya; Kajiyama, Hiroaki; Kikkawa, Fumitaka; Metelmann, Hans-Robert; Hori, Masaru

2017-12-01

Plasma medical science is a novel interdisciplinary field that combines studies on plasma science and medical science, with the anticipation that understanding the scientific principles governing plasma medical science will lead to innovations in the field. Non-thermal atmospheric pressure plasma has been used for medical treatments, such as for cancer, blood coagulation, and wound healing. The interactions that occur between plasma and cells/tissues have been analyzed extensively. Direct and indirect treatment of cells with plasma has broadened the applications of non-thermal atmospheric pressure plasma in medicine. Examples of indirect treatment include plasma-assisted immune-therapy and plasma-activated medium. Controlling intracellular redox balance may be key in plasma cancer treatment. Animal studies are required to test the effectiveness and safety of these treatments for future clinical applications.

Promoting Pre-college Science Education

NASA Astrophysics Data System (ADS)

Taylor, P. L.; Lee, R. L.

2000-10-01

The Fusion Education Program, with continued support from DOE, has strengthened its interactions with educators in promoting pre-college science education for students. Projects aggressively pursued this year include an on-site, college credited, laboratory-based 10-day educator workshop on plasma and fusion science; completion of `Starpower', a fusion power plant simulation on interactive CD; expansion of scientist visits to classrooms; broadened participation in an internet-based science olympiad; and enhancements to the tours of the DIII-D Facility. In the workshop, twelve teachers used bench top devices to explore basic plasma physics. Also included were radiation experiments, computer aided drafting, techniques to integrate fusion science and technology in the classroom, and visits to a University Physics lab and the San Diego Supercomputer Center. Our ``Scientist in a Classroom'' program reached more than 2200 students at 20 schools. Our `Starpower' CD allows a range of interactive learning from the effects of electric and magnetic fields on charged particles to operation of a Tokamak-based power plant. Continuing tours of the DIII-D facility were attended by more than 800 students this past year.

Rocket experiment METS Microwave Energy Transmission in Space

NASA Astrophysics Data System (ADS)

Kaya, N.; Matsumoto, H.; Akiba, R.

A METS (Microwave Energy Transmission in Space) rocket experiment is being planned by the SPS (Solar Power Satellite) Working Group at the Institute of Space and Astronautical Science (ISAS) in Japan for the forthcoming International Space Year (ISY), 1992. The METS experiment is an advanced version of our MINIX rocket experiment. This paper describes the conceptual design for the METS rocket experiment. Aims are to verify the feasibility of a newly developed microwave energy transmission system designed for use in space and to study nonlinear effects of the microwave energy beam on space plasma. A high power microwave (936 W) will be transmitted by a new phase-array antenna from a mother rocket to a separate target (daughter rocket) through the Earth's ionospheric plasma. The active phased-array system has the capability of being able to focus the microwave energy at any spatial point by individually controlling the digital phase shifters.

Rocket experiment METS - Microwave Energy Transmission in Space

NASA Astrophysics Data System (ADS)

Kaya, N.; Matsumoto, H.; Akiba, R.

A Microwave Energy Transmission in Space (METS) rocket experiment is being planned by the Solar Power Satellite Working Group at the Institute of Space and Astronautical Science in Japan for the forthcoming International Space Year, 1992. The METS experiment is an advanced version of the previous MINIX rocket experiment (Matsumoto et al., 1990). This paper describes a conceptual design of the METS rocket experiment. It aims at verifying a newly developed microwave energy transmission system for space use and to study nonlinear effects of the microwave energy beam in the space plasma environment. A high power microwave of 936 W will be transmitted by the new phased-array antenna from a mother rocket to a separated target (daughter rocket) through the ionospheric plasma. The active phased-array system has a capability of focusing the microwave energy around any spatial point by controlling the digital phase shifters individually.

PEPE is installed on Deep Space 1 in the PHSF

NASA Technical Reports Server (NTRS)

1998-01-01

The Plasma Experiment for Planetary Exploration (PEPE), one of two advanced science experiments flying on the Deep Space l mission, is prepared for installation on the spacecraft in the Payload Hazardous Servicing Facility. PEPE combines several instruments that study space plasma in one compact 13-pound (6- kilogram) package. Space plasma is composed of charged particles, most of which flow outward from the Sun. The first flight in NASA's New Millennium Program, Deep Space 1 is designed to validate 12 new technologies for scientific space missions of the next century. The spacecraft is scheduled to launch during a period opening Oct. 15 and closing Nov. 10, 1998. Most of its mission objectives will be completed within the first two months. A near-earth asteroid, 1992 KD, has also been selected for a possible flyby.

X-ray Heating and Electron Temperature of Laboratory Photoionized Plasmas

NASA Astrophysics Data System (ADS)

Mancini, Roberto; Lockard, Tom; Mayes, Daniel C.; Loisel, Guillaume; Bailey, James E.; Rochau, Gregory; Abdallah, J.; Golovkin, I.

2018-06-01

In separate experiments performed at the Z facility of Sandia National Laboratories two different samples were employed to produce and characterize photoionized plasmas. One was a gas cell filled with neon, and the other was a thin silicon layer coated with plastic. Both samples were driven by the broadband x-ray flux produced at the collapse of a wire array z-pinch implosion. Transmission spectroscopy of a narrowband portion of the x-ray flux was used to diagnose the charge state distribution, and the electron temperature was extracted from a Li-like ion level population ratio. To interpret the temperature measurement, we performed Boltzmann kinetics and radiation-hydrodynamic simulations. We found that non-equilibrium atomic physics and the coupling of the radiation flux to the atomic level population kinetics play a critical role in modeling the x-ray heating of photoionized plasmas. In spite of being driven by similar x-ray drives, differences of ionization and charged state distributions in the neon and silicon plasmas are reflected in the plasma heating and observed electron temperatures.This work was sponsored in part by DOE Office of Science Grant DE-SC0014451, and the Z Facility Fundamental Science Program of SNL.

Characterization of >100 T magnetic fields associated with relativistic Weibel instability in laser-produced plasmas

NASA Astrophysics Data System (ADS)

Mishra, Rohini; Ruyer, Charles; Goede, Sebastian; Roedel, Christian; Gauthier, Maxence; Zeil, Karl; Schramm, Ulrich; Glenzer, Siegfried; Fiuza, Frederico

2016-10-01

Weibel-type instabilities can occur in weakly magnetized and anisotropic plasmas of relevance to a wide range of astrophysical and laboratory scenarios. It leads to the conversion of a significant fraction of the kinetic energy of the plasma into magnetic energy. We will present a detailed numerical study, using 2D and 3D PIC simulations of the Weibel instability in relativistic laser-solid interactions. In this case, the instability develops due to the counter-streaming of laser-heated electrons and the background return current. We show that the growth rate of the instability is maximized near the critical density region on the rear side of the expanded plasma, producing up to 400 MG magnetic fields for Hydrogen plasmas. We have found that this strong field can be directly probed by energetic protons accelerated in rear side of the plasma by Target Normal Sheath Acceleration (TNSA). This allows the experimental characterization of the instability from the analysis of the spatial modulation of the detected protons. Our numerical results are compared with recent laser experiments with Hydrogen jets and show good agreement with the proton modulations observed experimentally. This work was supported by the DOE Office of Science, Fusion Energy Science (FWP 100182).

The design and implementation of the Dynamic Ionosphere Cubesat Experiment (DICE) science instruments

NASA Astrophysics Data System (ADS)

Burr, Steven Reed

Dynamic Ionosphere Cubesat Experiment (DICE) is a satellite project funded by the National Science Foundation (NSF) to study the ionosphere, more particularly Storm Enhanced Densities (SED) with a payload consisting of plasma diagnostic instrumentation. Three instruments onboard DICE include an Electric Field Probe (EFP), Ion Langmuir Probe (ILP), and Three Axis Magnetometer (TAM). The EFP measures electric fields from +/-8V and consists of three channels a DC to 40Hz channel, a Floating Potential Probe (FPP), and an spectrographic channel with four bands from 16Hz to 512Hz. The ILP measures plasma densities from 1x104 cm--3 to 2x107 cm--3. The TAM measures magnetic field strength with a range +/-0.5 Gauss with a sensitivity of 2nT. To achieve desired mission requirements careful selection of instrument requirements and planning of the instrumentation design to achieve mission success. The analog design of each instrument is described in addition to the digital framework required to sample the science data at a 70Hz rate and prepare the data for the Command and Data Handing (C&DH) system. Calibration results are also presented and show fulfillment of the mission and instrumentation requirements.

Measurement of OH, NO, O and N atoms in helium plasma jet for ROS/RNS controlled biomedical processes

NASA Astrophysics Data System (ADS)

Yonemori, Seiya; Kamakura, Taku; Ono, Ryo

2014-10-01

Atmospheric-pressure plasmas are of emerging interest for new plasma applications such as cancer treatment, cell activation and sterilization. In those biomedical processes, reactive oxygen/nitrogen species (ROS/RNS) are said that they play significant role. It is though that active species give oxidative stress and induce biomedical reactions. In this study, we measured OH, NO, O and N atoms using laser induced fluorescence (LIF) measurement and found that voltage polarity affect particular ROS. When negative high voltage was applied to the plasma jet, O atom density was tripled compared to the case of positive applied voltage. In that case, O atom density was around 3 × 1015 [cm-3] at maximum. In contrast, OH and NO density did not change their density depending on the polarity of applied voltage, measured as in order of 1013 and 1014 [cm-3] at maximum, respectively. From ICCD imaging measurement, it could be seen that negative high voltage enhanced secondary emission in plasma bullet propagation and it can affect the effective production of particular ROS. Since ROS/RNS dose can be a quantitative criterion to control plasma biomedical application, those measurement results is able to be applied for in vivo and in vitro plasma biomedical experiments. This study is supported by the Grant-in-Aid for Science Research by the Ministry of Education, Culture, Sport, Science and Technology.

Plasma Density Effects on Toroidal Flow Stabilization of Edge Localized Modes

NASA Astrophysics Data System (ADS)

Cheng, Shikui; Zhu, Ping; Banerjee, Debabrata

2016-10-01

Recent EAST experiments have demonstrated mitigation and suppression of edge localized modes (ELMs) with toroidal rotation flow in higher collisionality regime, suggesting potential roles of plasma density. In this work, the effects of plasma density on the toroidal flow stabilization of the high- n edge localized modes have been extensively studied in linear calculations for a circular-shaped limiter H-mode tokamak, using the initial-value extended MHD code NIMROD. In the single MHD model, toroidal flow has a weak stabilizing effects on the high- n modes. Such a stabilization, however, can be significantly enhanced with the increase in plasma density. Furthermore, our calculations show that the enhanced stabilization of high- n modes from toroidal flow with higher edge plasma density persists in the 2-fluid MHD model. These findings may explain the ELM mitigation and suppression by toroidal rotation in higher collisionality regime due to the enhancement of plasma density obtained in EAST experiment. Supported by the National Magnetic Confinement Fusion Program of China under Grant Nos. 2014GB124002 and 2015GB101004, the 100 Talent Program and the President International Fellowship Initiative of Chinese Academy of Sciences.

ADX: a high field, high power density, Advanced Divertor test eXperiment

NASA Astrophysics Data System (ADS)

Vieira, R.; Labombard, B.; Marmar, E.; Irby, J.; Shiraiwa, S.; Terry, J.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; ADX Team

2014-10-01

The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) - a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S ~ 1.5 MW/m2) facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side - a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R&D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO - in a timely manner, on a cost-effective research platform. Supported by DE-FC02-99ER54512.

Survey of the plasma electron environment of Jupiter: A view from Voyager

NASA Technical Reports Server (NTRS)

Scudder, J. D.; Sittler, E. C., Jr.; Bridge, H. S.

1980-01-01

The plasma environment within Jupiter's bow shock is considered in terms of the in situ, calibrated electron plasma measurements made between 10 eV and 5.95 keV by the Voyager plasma science experiment (PLS). Measurements were analyzed and corrected for spacecraft potential variations; the data were reduced to nearly model independent macroscopic parameters of the local electron density and temperature. It is tentatively concluded that the radial temperature profile within the plasma sheet is caused by the intermixing of two different electron populations that probably have different temporal histories and spatial paths to their local observation. The cool plasma source of the plasma sheet and spikes is probably the Io plasma torus and arrives in the plasma sheet as a result of flux tube interchange motions or other generalized transport which can be accomplished without diverting the plasma from the centrifugal equator. The hot suprathermal populations in the plasma sheet have most recently come from the sparse, hot mid-latitude "bath" of electrons which were directly observed juxtaposed to the plasma sheet.

The response function of modulated grid Faraday cup plasma instruments

NASA Technical Reports Server (NTRS)

Barnett, A.; Olbert, S.

1986-01-01

Modulated grid Faraday cup plasma analyzers are a very useful tool for making in situ measurements of space plasmas. One of their great attributes is that their simplicity permits their angular response function to be calculated theoretically. An expression is derived for this response function by computing the trajectories of the charged particles inside the cup. The Voyager Plasma Science (PLS) experiment is used as a specific example. Two approximations to the rigorous response function useful for data analysis are discussed. The theoretical formulas were tested by multi-sensor analysis of solar wind data. The tests indicate that the formulas represent the true cup response function for all angles of incidence with a maximum error of only a few percent.

14th High-Tech Plasma Processes Conference (HTPP 14)

NASA Astrophysics Data System (ADS)

2017-04-01

Preface The High-Tech Plasma Processes Conference (HTPP) is a bi-annual international conference based in Europe with topics encompassing the whole area of plasma processing science. This conference is open to all the international community in the world involved in plasma science and plasma technology. The aim of the conference is to bring different scientific communities together, facilitate the contacts between science, technology and industry and provide a platform for the exploration of both fundamental topics and new applications of plasmas. For this edition of HTPP, as was the case for the last, we have achieved a well balanced participation from the communities of both thermal and non-thermal plasma researchers. 75 people from 17 countries attended the conference with the total number of contributions being 74, consisting of 19 invited talks and 55 poster contributions. As a HTPP tradition a poster competition has been carried out during the conference. The winner of the poster competition was Fabrice Mavier from Université de Limoges, France with his paper “Pulsed arc plasma jet synchronized with drop-on-demand dispenser” All the participants also ejoyed the social program including an “unconventional” tour of the city, the visit to the famous Hofbräuhaus and the dinner at the Blutenburg, a beautiful inner-city castle. We have received papers corresponding to the contributions of HTPP-2014 that have been submitted for publication in this volume of Journal of Physics: Conference Series. Each submitted contribution has been peer reviewed and the Editors are very grateful to the referees for their careful support in improving the original manuscripts. In total, 18 manuscripts have been accepted for publication covering a range of topics of plasma processing science from plasma fundamentals to process applications through to experiments, diagnostics and modelling. We deeply thank the authors for their enthusiastic and high-grade contributions and we are convinced that this volume of Journal of Physics: Conference Series will be interesting for our community. Finally, we would like to thank the conference chairmen, the members of the steering committee, the international scientific committee, the local organizing committee, the organizing secretariat and the financial support from the conference sponsors that allowed the success of HTPP-2016. The Editors of the HTPP-2016 Proceedings Dr. Dirk Uhrlandt, head of the ISC Prof. Philippe Teulet Prof. Jochen Schein Neubiberg, 6th of March 2017

Radar investigation of barium releases over Arecibo Observatory, Puerto Rico

NASA Technical Reports Server (NTRS)

Djuth, Frank T.

1995-01-01

The NASA Combined Release and Radiation Effects Satellite (CRRES) El Coqui rocket campaign was successfully carried out in Puerto Rico during the period 18 May through 12 July 1992. This report describes five chemical release experiments in the upper ionosphere supported by Geospace Research, Inc. during the El Coqui campaign. Additional spin-off science is also discussed. The El Coqui releases are designated AA-1 (rocket 36-082), AA-2 (rocket 36-081), AA-3b (rocket 36-064), AA-4 (rocket 36-065), and AA-7 (rocket 36-083). Particular attention is paid to releases AA-2 and AA-4. These two experiments involved the illumination of ionospheric release regions with powerful high-frequency (HF) radio waves transmitted from the Arecibo HF facility. In the AA-2 experiment, microinstabilities excited by the HF wave in a Ba(+) plasma were examined. This release yielded a smooth plasma cloud that helped clarify several fundamental issues regarding the physics of wave plasma instabilities. During AA-2 extremely strong HF-induced Langmuir turbulence was detected with the Arecibo 430 MHz radar. CF3Br was released in the AA-4 study to create an ionospheric hole that focused the HF beam. This experiment successfully explored wave-plasma coupling in an O(+) ionosphere under conditions of very high HF electric field strengths.

Planetary science

NASA Technical Reports Server (NTRS)

Marshall, John R.; Bridges, Frank; Gault, Donald; Greeley, Ronald; Houpis, Harry; Lin, Douglas; Weidenschilling, Stuart

1987-01-01

The following types of experiments for a proposed Space Station Microgravity Particle Research Facility are described: (1) low velocity collisions between fragile particles; (2) low velocity collisions of ice particles; (3) plasma-dust interaction; and (4) aggregation of finely-comminuted geological materials. The required capabilities and desired hardware for the facility are detailed.

Review of the magnetic fusion program by the 1986 ERAB Fusion Panel

NASA Astrophysics Data System (ADS)

Davidson, Ronald C.

1987-09-01

The 1986 ERAB Fusion Panel finds that fusion energy continues to be an attractive energy source with great potential for the future, and that the magnetic fusion program continues to make substantial technical progress. In addition, fusion research advances plasma physics, a sophisticated and useful branch of applied science, as well as technologies important to industry and defense. These factors fully justify the substantial expenditures by the Department of Energy in fusion research and development (R&D). The Panel endorses the overall program direction, strategy, and plans, and recognizes the importance and timeliness of proceeding with a burning plasma experiment, such as the proposed Compact Ignition Tokamak (CIT) experiment.

Juno Radio Science Observations and Gravity Science Calibrations of Plasma Electron Content in Io Plasma Torus

NASA Astrophysics Data System (ADS)

Yang, Y. M.; Buccino, D.; Folkner, W. M.; Oudrhiri, K.; Phipps, P. H.; Parisi, M.; Kahan, D. S.

2017-12-01

Interplanetary and Earth ionosphere plasma electrons can have significant impacts on radio frequency signal propagation such as telecommunication between spacecraft and the Deep Space Network (DSN). On 27 August 2016, the first closest approach of The Juno spacecraft (Perijove 1) provided an opportunity to observe plasma electrons inside of the Io plasma torus using radio science measurements from Juno. Here, we report on the derivations of plasma electron content in the Io plasma torus by using two-way coherent radio science measurements made from Juno's Gravity Science Instrument and the Deep Space Network. During Perijove 1, Juno spacecraft passed through the inner region (perijove altitude of 1.06 Jovian Radii) between Jupiter and the Io plasma torus. Significant plasma electron variations of up to 30 TEC units were observed while the radio link between Juno and the DSN traveled through the Io plasma torus. In this research, we compare observations made by open-loop and closed-loop processes using different frequency radio signals, corresponding Io plasma torus model simulations, and other Earth ionosphere observations. The results of three-dimensional Io plasma model simulations are consistent with observations with some discrepancies. Results are shown to improve our understanding of the Io plasma torus effect on Juno gravity science measurements and its calibrations to reduce the corresponding (non-gravity field induced) radio frequency shift.

The first Spacelab payload - A joint NASA/ESA venture

NASA Technical Reports Server (NTRS)

Kennedy, R.; Pace, R.; Collet, J.; Sanfourche, J. P.

1977-01-01

Planning for the 1980 qualification flight of Spacelab, which will involve a long module and one pallet, is discussed. The mission will employ two payload specialists, one sponsored by NASA and the other by ESA. Management of the Spacelab mission functions, including definition and execution of the on-board experiments, development of the experimental hardware and training of the payload specialists, is considered; studies proposed in the areas of atmospheric physics, space plasma physics, solar physics, earth observations, astronomy, astrophysics, life sciences and material sciences are reviewed. Analyses of the Spacelab environment and the Spacelab-to-orbiter and Spacelab-to-experiment interactions are also planned.

Optimisation of parameters of Raman laser pulse compression in a plasma for its implementation using the PEARL laser facility (IAP RAS)

NASA Astrophysics Data System (ADS)

Balakin, A. A.; Levin, D. S.; Skobelev, S. A.

2018-04-01

We consider Raman compression of laser pulses in a plasma under the conditions of an experiment planned at the Institute of Applied Physics of the Russian Academy of Sciences on the PEARL laser facility. The analysis is based on the equations describing, among other things, the effect of plasma dispersion and relativistic nonlinearity, as well as the dynamics of the field near the plasma wave breaking threshold. It is shown that the main limiting factors are excessive frequency modulation of the pump pulse and a too low plasma density in which the plasma wave breaking can occur. To reduce the negative influence of these effects, we suggest using an intense and short (on the order of the plasma period) seed laser pulse. Numerical simulation shows the possibility of a hundredfold increase in the intensity of the compressed pulse in comparison with the intensity of the pump pulse at a length of uniform plasma of 2 cm.

Plasma bulk flow in Jupiter's dayside middle magnetosphere

NASA Technical Reports Server (NTRS)

Sands, Mark R.; Mcnutt, Ralph L., Jr.

1988-01-01

Using the plasma data obtained during the Voyager 1 encounter and the full response function of the Plasma Science (PLS) experiment, convective plasma velocities have been determined in the dayside middle magnetosphere of Jupiter (r = 10-25 Jupiter radii). It is found that temperature anisotropies have very little effect on plasma velocity determination and that the plasma data are well approximated by convected, isotropic Maxwellian ion distribution functions. The insensitivity of the analysis to any thermal anisotropies which may exist allows a good determination of the bulk plasma flow velocity. In addition to the subcorotational azimuthal flow, there exists a substantial nonazimuthal component of plasma flow. This nonazimuthal flow is mostly aligned (antialigned) with the local magnetic field but also exhibits a cross-field component. The velocity pattern is inconsistent with enhanced plasma outflow in the active sector, as suggested by the corotating convection model of plasma transport. The contribution of field-aligned flow along the curved magnetic field lines to the stress on the magnetic field is evaluated. In the region studied, such flow contributes up to one half the stress produced by the azimuthal plasma flow.

Design and Assembly of the Magnetized Dusty Plasma Experiment (MDPX)

NASA Astrophysics Data System (ADS)

Fisher, Ross; Artis, Darrick; Lynch, Brian; Wood, Keith; Shaw, Joseph; Gilmore, Kevin; Robinson, Daniel; Polka, Christian; Konopka, Uwe; Thomas, Edward; Merlino, Robert; Rosenberg, Marlene

2013-10-01

Over the last two years, the Magnetized Dusty Plasma Experiment (MDPX) has been under construction at Auburn University. This new research device, whose assembly will be completed in late Summer, 2013, uses a four-coil, superconducting, high magnetic field system (|B | >= 4 Tesla) to investigate the confinement, charging, transport, and instabilities in a dusty plasma. A new feature of the MDPX device is the ability to operate the magnetic coils independently to allow a variety of magnetic configurations from highly uniform to quadrapole-like. Envisioned as a multi-user facility, the MDPX device features a cylindrical vacuum vessel whose primary experimental region is an octagonal chamber that has a 35.5 cm inner diameter and is 19 cm tall. There is substantial diagnostics and optical access through eight, 10.2 cm × 12.7 cm side ports. The chamber can also be equipped with two 15.2 cm diameter, 76 cm long extensions to allow long plasma column experiments, particularly long wavelength dust wave studies. This presentation will discuss the final design, assembly, and installation of the MDPX device and will describe its supporting laboratory facility. This work is supported by a National Science Foundation - Major Research Instrumentation (NSF-MRI) award, PHY-1126067.

Role of Laboratory Plasma Experiments in exploring the Physics of Solar Eruptions

NASA Astrophysics Data System (ADS)

Tripathi, S.

2017-12-01

Solar eruptive events are triggered over a broad range of spatio-temporal scales by a variety of fundamental processes (e.g., force-imbalance, magnetic-reconnection, electrical-current driven instabilities) associated with arched magnetoplasma structures in the solar atmosphere. Contemporary research on solar eruptive events is at the forefront of solar and heliospheric physics due to its relevance to space weather. Details on the formation of magnetized plasma structures on the Sun, storage of magnetic energy in such structures over a long period (several Alfven transit times), and their impulsive eruptions have been recorded in numerous observations and simulated in computer models. Inherent limitations of space observations and uncontrolled nature of solar eruptions pose significant challenges in testing theoretical models and developing the predictive capability for space-weather. The pace of scientific progress in this area can be significantly boosted by tapping the potential of appropriately scaled laboratory plasma experiments to compliment solar observations, theoretical models, and computer simulations. To give an example, recent results from a laboratory plasma experiment on arched magnetic flux ropes will be presented and future challenges will be discussed. (Work supported by National Science Foundation, USA under award number 1619551)

Kinetic Modeling of Ultraintense X-ray Laser-Matter Interactions

NASA Astrophysics Data System (ADS)

Royle, Ryan; Sentoku, Yasuhiko; Mancini, Roberto

2016-10-01

Hard x-ray free-electron lasers (XFELs) have had a profound impact on the physical, chemical, and biological sciences. They can produce millijoule x-ray laser pulses just tens of femtoseconds in duration with more than 1012 photons each, making them the brightest laboratory x-ray sources ever produced by several orders of magnitude. An XFEL pulse can be intensified to 1020 W/cm2 when focused to submicron spot sizes, making it possible to isochorically heat solid matter well beyond 100 eV. These characteristics enable XFELs to create and probe well-characterized warm and hot dense plasmas of relevance to HED science, planetary science, laboratory astrophysics, relativistic laser plasmas, and fusion research. Several newly developed atomic physics models including photoionization, Auger ionization, and continuum-lowering have been implemented in a particle-in-cell code, PICLS, which self-consistently solves the x-ray transport, to enable the simulation of the non-LTE plasmas created by ultraintense x-ray laser interactions with solid density matter. The code is validated against the results of several recent experiments and is used to simulate the maximum-intensity x-ray heating of solid iron targets. This work was supported by DOE/OFES under Contract No. DE-SC0008827.

Investigating Trapped Particle Asymmetry Modes and Temperature Effects in the Lawrence Non-neutral Torus II

NASA Astrophysics Data System (ADS)

Nirwan, R.; Swanson, P.; Stoneking, M. R.

2017-10-01

Electron plasma is confined in the Lawrence Non-Neutral Torus II using a purely toroidal magnetic field (R0 = 18 cm, B < 1 kG) for confinement times exceeding 1 second. The LNT II can be configured for fully toroidal traps or variable-length partial toroidal traps. The behavior of the plasma is observed by monitoring the image charge on isolated wall sectors. The plasma is excited by application of a sinusoidal tone burst to selected wall sectors. Phase-space separatrices are introduced by applying squeeze potentials to toroidally localized, but poloidally continuous sectors and the resulting interaction between trapped and passing particles populations results in asymmetry modes and transport. These experiments provide a comparison with similar experiments in cylindrical traps. We also report on the development of temperature measurement techniques and assess temperature affects on diocotron and asymmetry modes. This work is supported by National Science Foundation Grant No. PHY-1202540.

An Experiment to Study Sporadic Sodium Layers in the Earth's Mesosphere and Lower Thermosphere

NASA Technical Reports Server (NTRS)

Swenson, Charles M.

2002-01-01

The Utah State University / Space Dynamics Lab was funded under a NASA Grant. This investigation has been part of Rockwell Universities Sudden Atom Layer Investigation (SAL). USU/SDL provided an electron density measurement instrument, the plasma frequency probe, which was launched on the vehicle 21.117 from Puerto-Rico in February of 1998. The instrument successfully measured electron density as designed and measurement techniques included in this version of the Plasma Frequency probe provided valuable insight into the electron density structures associated with sudden sodium layers in a collisional plasma. Electron density data was furnished to Rockwell University but no science meetings were held by Rockwell Data from the instrument was presented to the scientific community at the URSI General Session in 1999. A paper is in preparation for publication in Geophysical Research Letters. The following document provides a summary of the experiment and data obtained as a final report on this grant.

Measurements of Ion and Neutral Fluctuation Changes with Pressure in a Large-Scale Helicon Plasma

NASA Astrophysics Data System (ADS)

Dwyer, R. H.; Fisher, D. M.; Kelly, R. F.; Hatch, M. W.; Gilmore, M.

2017-10-01

Neutral particle dynamics may play an important role both in laboratory plasmas and in the edge of magnetic fusion devices. However, studies of neutral dynamics in these plasmas have been limited to date. Here we report on a basic study of ion and neutral fluctuations as a function of background neutral gas pressure. These experiments have been conducted in helicon discharges in the HelCat (Helicon-Cathode) dual-source plasma device at the University of New Mexico. The goal is to measure changes in ion and neutral density fluctuations with pressure and to gain an improved understanding of plasma-neutral interactions. Langmuir probe, Ar-I LIF, and high-speed imaging measurements of the fluctuations will be presented. Supported by U.S. National Science Foundation Award 1500423 and The University of New Mexico School of Engineering.

Overview of HIT-SI3 experiment: Simulations, Diagnostics, and Summary of Current Results

NASA Astrophysics Data System (ADS)

Penna, James; Jarboe, Thomas; Nelson, Brian; Hossack, Aaron; Sutherland, Derek; Morgan, Kyle; Hansen, Chris; Benedett, Thomas; Everson, Chris; Victor, Brian

2016-10-01

The Helicity Injected Torus - Steady Inductive 3(HIT-SI3)experiment forms and maintains spheromaks via Steady Inductive Helicity Injection (SIHI). Three injector units allow for continuous injection of helicity into a copper flux conserver in order to sustain a spheromak. Firing of the injectors with a phase difference allows finite rotation of the plasma to provide a stabilizing effect. Simulations in the MHD code NIMROD and the fluid-model code PSI-TET provide validation and a basis for interpretation of the observed experimental data. Thompson Scattering (TS) and Far Infrared (FIR) Interferometer systems allow temperature and line-averaged density measurements to be taken. An Ion Doppler Spectroscopy (IDS) system allows measurement of the plasma rotation and velocity. HIT-SI3 data has been used for validation of IDCD predictions, in particular the projected impedance of helicity injectors according to the theory. The experimental impedances have been calculated here for the first time for different HIT-SI3 regimes. Such experimental evidence will contribute to the design of future experiments employing IDCD as a current-drive mechanism. Work supported by the D.O.E., Office of Science, Office of Fusion Science.

Interactions of Deuterium Plasma with Lithiated and Boronized Surfaces in NSTX-U

NASA Astrophysics Data System (ADS)

Krstic, Predrag

2015-09-01

The main research goal of the presented research has been to understand the changes in surface composition and chemistry at the nanoscopic temporal and spatial scales for long pulse Plasma Facing Components (PFCs) and link these to the overall machine performance of the National Spherical Torus Experiment Upgrade (NSTX-U). A study is presented of the lithium surface science, with atomic spatial and temporal resolutions. The dynamic surface responds and evolves in a mixed material environments (D, Li, C, B, O, Mo, W) with impingement of plasma particles in the energy range below 100 eV. The results, obtained by quantum-classical molecular dynamics, include microstructure changes, erosion, surface chemistry, deuterium implantation and permeation. Main objectives of the research are i) a comparison of Li and B deposition on carbon, ii) the role of oxygen and other impurities e.g. boron, carbon in the lithium performance, and iii) how this performance will change when lithium is applied to a high-Z refractory metal substrate (Mo, W). In addition to predicting and understanding the phenomenology of the processes, we will show plasma induced erosion of PFCs, including chemical and physical sputtering yields at various temperatures (300-700 K) as well as deuterium uptake/recycling. This work is supported by the U.S. Department of Energy Office of Science, Office of Fusion Energy Science, Award Number DE-SC0013752.

Studying astrophysical particle acceleration with laser-driven plasmas

NASA Astrophysics Data System (ADS)

Fiuza, Frederico

2016-10-01

The acceleration of non-thermal particles in plasmas is critical for our understanding of explosive astrophysical phenomena, from solar flares to gamma ray bursts. Particle acceleration is thought to be mediated by collisionless shocks and magnetic reconnection. The microphysics underlying these processes and their ability to efficiently convert flow and magnetic energy into non-thermal particles, however, is not yet fully understood. By performing for the first time ab initio 3D particle-in-cell simulations of the interaction of both magnetized and unmagnetized laser-driven plasmas, it is now possible to identify the optimal parameters for the study of particle acceleration in the laboratory relevant to astrophysical scenarios. It is predicted for the Omega and NIF laser conditions that significant non-thermal acceleration can occur during magnetic reconnection of laser-driven magnetized plasmas. Electrons are accelerated by the electric field near the X-points and trapped in contracting magnetic islands. This leads to a power-law tail extending to nearly a hundred times the thermal energy of the plasma and that contains a large fraction of the magnetic energy. The study of unmagnetized interpenetrating plasmas also reveals the possibility of forming collisionless shocks mediated by the Weibel instability on NIF. Under such conditions, both electrons and ions can be energized by scattering out of the Weibel-mediated turbulence. This also leads to power-law spectra that can be detected experimentally. The resulting experimental requirements to probe the microphysics of plasma particle acceleration will be discussed, paving the way for the first experiments of these important processes in the laboratory. As a result of these simulations and theoretical analysis, there are new experiments being planned on the Omega, NIF, and LCLS laser facilities to test these theoretical predictions. This work was supported by the SLAC LDRD program and DOE Office of Science, Fusion Energy Science (FWP 100182).

Pulse Front Tilt and Laser Plasma Acceleration

NASA Astrophysics Data System (ADS)

Mittelberger, Daniel; Thévenet, Maxence; Nakamura, Kei; Lehe, Remi; Gonsalves, Anthony; Benedetti, Carlo; Leemans, Wim

2017-10-01

Pulse front tilt (PFT) is potentially present in any CPA laser system, but its effects may be overlooked because spatiotemporal pulse characterization is considerably more involved than measuring only spatial or temporal profile. PFT is particularly important for laser plasma accelerators (LPA) because it influences electron beam injection and steering. In this work, experimental results from the BELLA Center will be presented that demonstrate the effect of optical grating misalignment and optical compression, resulting in PFT, on accelerator performance. Theoretical models of laser and electron beam steering will be introduced based on particle-in-cell simulations showing distortion of the plasma wake. Theoretical predictions will be compared with experiments and complimentary simulations, and tolerances on PFT and optical compressor alignment will be developed as a function of LPA performance requirements. This work was supported by the Office of High Energy Physics, Office of Science, US Department of Energy under Contract DE-AC02-05CH11231 and the National Science Foundation under Grant PHY-1415596.

PANDORA, a new facility for interdisciplinary in-plasma physics

NASA Astrophysics Data System (ADS)

Mascali, D.; Musumarra, A.; Leone, F.; Romano, F. P.; Galatà, A.; Gammino, S.; Massimi, C.

2017-07-01

PANDORA, Plasmas for Astrophysics, Nuclear Decays Observation and Radiation for Archaeometry, is planned as a new facility based on a state-of-the-art plasma trap confining energetic plasma for performing interdisciplinary research in the fields of Nuclear Astrophysics, Astrophysics, Plasma Physics and Applications in Material Science and Archaeometry: the plasmas become the environment for measuring, for the first time, nuclear decay rates in stellar-like condition (such as 7Be decay and beta-decay involved in s-process nucleosynthesis), especially as a function of the ionization state of the plasma ions. These studies will give important contributions for addressing several astrophysical issues in both stellar and primordial nucleosynthesis environment ( e.g., determination of solar neutrino flux and 7Li Cosmological Problem), moreover the confined energetic plasma will be a unique light source for high-performance stellar spectroscopy measurements in the visible, UV and X-ray domains, offering advancements in observational astronomy. As to magnetic fields, the experimental validation of theoretical first- and second-order Landé factors will drive the layout of next-generation polarimetric units for the high-resolution spectrograph of the future giant telescopes. In PANDORA new plasma heating methods will be explored, that will push forward the ion beam output, in terms of extracted intensity and charge states. More, advanced and optimized injection methods of ions in an ECR plasma will be experimented, with the aim to optimize its capture efficiency. This will be applied to the ECR-based Charge Breeding technique, that will improve the performances of the SPES ISOL-facility at Laboratori Nazionali di Legnaro-INFN. Finally, PANDORA will be suitable for energy conversion, making the plasma a source of high-intensity electromagnetic radiation, for applications in material science and archaeometry.

Message From the Editor for Contributions to the 2016 Real Time Conference Issue of TNS

NASA Astrophysics Data System (ADS)

Schmeling, Sascha Marc

2017-06-01

This issue of the IEEE Transactions on Nuclear Science (TNS) is devoted to the 20th IEEE-NPSS Real Time Conference (RT2016) on Computing Applications in Nuclear and Plasma Sciences held in Padua, Italy, in June 2016. A total of 90 papers presented at the conference were submitted for possible publication in TNS. This conference issue presents 46 papers, which have been accepted so far after a thorough peer review process. These contributions come from a very broad range of fields of application, including Astrophysics, Medical Imaging, Nuclear and Plasma Physics, Particle Accelerators, and Particle Physics Experiments. Several papers were close to being accepted but did not make it into this special issue. They will be considered for further publication.

Plasma properties at 67P/Churyumov-Gerasimenko: a comparision between PP-SESAME/Philae/Rosetta and RPC/MIP/Rosetta

NASA Astrophysics Data System (ADS)

Schmidt, Walter; Henri, Pierre; Lebreton, Jean Pierre; Vallières, Xavier; Grard, Réjean; Hamelin, Michel; Le Gall, Alice; Lethuillier, Anthony; Ciarletti, Valerie; Caujolle-Bert, Sylvain; Seidensticker, Klaus; Fischer, Hans-Herbert

2016-04-01

On November 12, 2014, the Rosetta landing module Philae approached the nucleus of 67P/Churyumov-Gerasimenko and eventually settled on the surface in a location named Abydos, though its exact coordinates are still unknown. The Permittivity Probe (PP) as part of the SESAME (Surface Electric Sounding and Acoustic Monitoring Experiment) instrument package [1] was designed to not only measure the electrical properties of the comet's surface material by actively injecting an alternating current at different frequencies into the material underneath the Lander but also to monitor potential variations between its two receivers and the electrical conductivity of the plasma environment while still in space. By sampling the potential difference at 40 kHz between the soles of two of the feet attached to Philae's landing gear, plasma waves between 20 and 20 000 Hz should be detectable if their amplitudes are large enough. The injection of low frequency currents into the plasma environment during Philae's descent gives indications for changes of the plasma density when approaching the comet. In this paper we present observations from the cross-calibration campaign with the Rosetta plasma package instrument MIP (Mutual Impedance Probe) [2] during the Pre-Delivery Calibration and Science (PDCS) operations on October 17, 2014, during the descent towards the comet surface on November 12, 2014, and from the First Science Sequence at Abydos on November 13. During the PDCS campaign most PP observation slots coincided with plasma waves dominantly in the 100 to 150 kHz range according to MIP measurements. Accordingly PP did not register any signals. Only in the afternoon of the 17th low frequency waves were recorded by MIP. At the same time the measured PP wave power signal was above the background for frequencies below 500 Hz in several subsequent measurements. During the descent [3] the injected current at 758 Hz dropped suddenly by about 5 % possibly indicating a decrease in the plasma density at an altitude of about 18.5 km above the comet surface. During the First Science Sequence PP was monitoring low frequency wave-like activities starting two hours after local sunset. References: [1] K. J. Seidensticker, H-H. Fischer, D. Medlener, S. Schieke, K. Thiel, A. Peter, W. Schmidt and R. Trautner, 2004: The Rosetta lander experiment sesame and the new target comet 67P/Churyumov-Gerasimenko. The New ROSETTA Targets - Observations, Simulations and Instrument Performances, Astrophys. Space Sci. 311, 297-307 [2] J. G. Trotignon et al., RPC-MIP: the Mutual Impedance Probe of the Rosetta Plasma Consortium, Space Science Reviews, February 2007, Volume 128, Issue 1, pp 713-728 [3] H.Krüger et al., Dust Impact Monitor (SESAME-DIM) Measurements at Comet 67P/Churyumov-Gerasimenko, Astronomy&Astrophysics, Volume 583, November 2015, DOI http://dx.doi.org/10.1051/0004-6361/201526400

Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

J.D. Levine; V.L. Finley

1998-03-01

The results of the 1996 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the US Department of Energy and the public with information on the level of radioactive and nonradioactive pollutants, if any, that are added to the environment as a result of PPPL's operations. During Calendar Year 1996, PPPL's Tokamak Fusion Test Reactor (TFTR) continued to conduct fusion experiments. Having set a world record on November 2, 1994, by achieving approximately 10.7 million watts of controlled fusion power during the deuterium-tritium (D-T) plasmamore » experiments, researchers turned their attention to studying plasma science experiments, which included ''enhanced reverse shear techniques.'' Since November 1993, more than 700 tritium-fueled experiments were conducted, which generated more than 4 x 10(superscript 20) neutrons and 1.4 gigajoules of fusion energy. In 1996, the overall performance of Princeton Plasma Physics Laboratory was rated ''excellent'' by the US Department of Energy in the Laboratory Appraisal report issued in early 1997. The report cited the Laboratory's consistently excellent scientific and technological achievements and its successful management practices, which included high marks for environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents) and petroleum hydrocarbons (past leaks of releases of diesel fuel from underground storage tanks). Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report. During 1996, PPPL completed the removal of contaminated soil from two locations that were identified through the monitoring program: petroleum hydrocarbons along a drainage swale and chromium adjacent to the cooling tower.« less

CATE 2016 Indonesia: Science goals and student training for 2017

NASA Astrophysics Data System (ADS)

Penn, M. J.; McKay, M. A.; Kovac, S. A.; Jensen, L.; Hare, H. S.; Mitchell, A. M.; Bosh, R.; Watson, Z.; Baer, R.; Pierce, M.; Gelderman, R.; Walter, D. K.

2016-12-01

The Citizen Continental-America Telescopic Eclipse (CATE) Experiment for 2017 is being developed at the National Solar Observatory in partnership with universities, schools, astronomy clubs, and corporations. The CATE experiment will use more than 60 identical telescopes equipped with digital cameras from Oregon to South Carolina to image the solar corona. The project will then splice these images together to show the corona during a 90-minute period, revealing for the first time the plasma dynamics of the inner solar corona. The goals for the CATE experiment range from providing an authentic STEM research experience for students and lifelong learners, to making state-of-the-art solar coronal observations of the plasma dynamics of coronal polar plumes, to increasing the US scientific literacy. Private funds are being raised for the CATE equipment, and so the telescopes will stay with the volunteers after the eclipse and be used in follow-on citizen science astronomy projects. The 2017 eclipse will be viewed by hundreds of millions of people. Four sets of undergraduate students in the path of the 2017 eclipse have become local experts for the eclipse and trainers for the CATE volunteers. These students traveled to the 2016 March eclipse in Indonesia and collected observations with prototype CATE telescopes; science results from these 2016 observations will be discussed. Training videos for use in 2017 were developed and tested on volunteers. Finally several high school groups along the path of totality have been engaged in the CATE project and will participate in the eclipse data collection. This work was supported by the NSO "Training for the 2017 Citizen CATE Experiment" funded by NASA (NASA NNX16AB92A). The National Solar Observatory is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the NSF.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

The vision described here builds on the present U.S. activities in fusion plasma and materials science relevant to the energy goal and extends plasma science at the frontier of discovery. The plan is founded on recommendations made by the National Academies, a number of recent studies by the Fusion Energy Sciences Advisory Committee (FESAC), and the Administration’s views on the greatest opportunities for U.S. scientific leadership.This report highlights five areas of critical importance for the U.S. fusion energy sciences enterprise over the next decade: 1) Massively parallel computing with the goal of validated whole-fusion-device modeling will enable a transformation inmore » predictive power, which is required to minimize risk in future fusion energy development steps; 2) Materials science as it relates to plasma and fusion sciences will provide the scientific foundations for greatly improved plasma confinement and heat exhaust; 3) Research in the prediction and control of transient events that can be deleterious to toroidal fusion plasma confinement will provide greater confidence in machine designs and operation with stable plasmas; 4) Continued stewardship of discovery in plasma science that is not expressly driven by the energy goal will address frontier science issues underpinning great mysteries of the visible universe and help attract and retain a new generation of plasma/fusion science leaders; 5) FES user facilities will be kept world-leading through robust operations support and regular upgrades. Finally, we will continue leveraging resources among agencies and institutions and strengthening our partnerships with international research facilities.« less

DAGON: a 3D Maxwell-Bloch code

NASA Astrophysics Data System (ADS)

Oliva, Eduardo; Cotelo, Manuel; Escudero, Juan Carlos; González-Fernández, Agustín.; Sanchís, Alberto; Vera, Javier; Vicéns, Sergio; Velarde, Pedro

2017-05-01

The amplification of UV radiation and high order harmonics (HOH) in plasmas is a subject of raising interest due to its different potential applications in several fields like environment and security (detection at distance), biology, materials science and industry (3D imaging) and atomic and plasma physics (pump-probe experiments). In order to develop these sources, it is necessary to properly understand the amplification process. Being the plasma an inhomogeneous medium which changes with time, it is desirable to have a full time-dependent 3D description of the interaction of UV and XUV radiation with plasmas. For these reasons, at the Instituto de Fusíon Nuclear we have developed DAGON, a 3D Maxwell-Bloch code capable of studying the full spationtemporal structure of the amplification process abovementioned.

Summary of initial results from the Magnetized Dusty Plasma Experiment (MDPX) device

NASA Astrophysics Data System (ADS)

Thomas, Edward

2015-11-01

Dusty (or complex) plasmas are four-component plasma systems consisting of electrons, ions, neutral atoms and charged, solid particulates. These particulates, i.e., the ``dust,'' become charged through interactions with the surrounding plasma particles and are therefore fully coupled to the background. The study of dusty plasmas began with astrophysical studies and has developed into a distinct area of plasma science with contributions to industrial, space, and fundamental plasma science. However, the vast majority of the laboratory studies are performed without the presence of a magnetic field. This is because, compared to the masses of the electrons and ions, the dust particles are significantly more massive and therefore the charge-to-mass ratio of the dust is very small. As a result, large (B > 1 T) magnetic fields are required to achieve conditions in which the dynamics of electrons, ions, and dust particles are dominated by the magnetic field. This presentation will provide a brief description of the design of the large bore (50 cm diameter x 158 cm long), multi-configuration, 4-Tesla class, superconducting magnet and integrated plasma chamber optimized for the study of dusty plasmas at high magnetic field - the MDPX device. The presentation will then focus on initial results of measurements made using MDPX - including observations of a new type of imposed ordered structures formed by the dust particles in a magnetized plasma, E x B driven flows of the particles, and observations of instabilities. This work is a collaboration of the author with Uwe Konopka (Auburn), Robert L. Merlino (Univ. of Iowa), Marlene Rosenberg (UCSD), and the MDPX team at Auburn University. Construction of the MDPX device was supported by the NSF-MRI program. Operations are supported by the NSF and DOE.

PREFACE: 13th High-Tech Plasma Processes Conference (HTPP-2014)

NASA Astrophysics Data System (ADS)

2014-11-01

The High-Tech Plasma Processes - 13th European Plasma Conference (HTPP-2014) was held in Toulouse (France) on 22-27 June 2014. The conference series started in 1990 as a thermal plasma conference and has gradually expanded to include other related topics. Now the High-Tech Plasma Processes - European Plasma Conference (HTPP) is an international conference organised in Europe every two years with topics encompassing the whole field of plasma processing science. The aim of the conference is to bring different scientific communities together, to facilitate contacts between science, technology and industry and to provide a platform for the exploration of both the fundamental topics and new applications of plasmas. For this edition of HTPP, as was the case for the last, we have acheived a well balanced participation from the communities of both thermal and non-thermal plasma researchers. 142 people from 17 countries attended the conference with the total number of contributions being 155, consisting of 8 plenary and 8 invited talks plus 51 oral and 88 poster contributions. We have received numerous papers corresponding to the contributions of HTPP-2014 that have been submitted for publication in this volume of Journal of Physics: Conference Series. Each submitted contribution has been peer reviewed (60 referees with at least two reviewing each paper) and the Editors are very grateful to the referees for their careful support in improving the original manuscripts. In total, 52 manuscripts have been accepted for publication covering a range of topics of plasma processing science from plasma fundamentals to process applications through to experiments, diagnostics and modelling. We have grouped the papers into the following 5 topics: - Arc-Materials Interaction and Metallurgy - Plasma Torches and Spraying - Synthesis of Powders and Nanomaterials - Deposition and Surface Treatment - Non-Equilibrium Plasmas We deeply thank the authors for their enthusiastic and high-grade contributions and we are convinced that this volume of Journal of Physics: Conference Series will be interesting for our community. Finally, we would like to thank the conference chairmen, the members of the steering committee, the international scientific committee, the local organizing committee, the organizing secretariat and the financial support from the conference sponsors that allowed the success of HTPP-2014. The Editors of the HTPP-2014 Proceedings Dr Alain Gleizes, chairman of HTPP-2014 Prof. Jochen Schein, head of the ISC Prof. Philippe Teulet Toulouse, 14th October 2014

A Star on Earth

ScienceCinema

Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

2018-02-14

At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucia, M., E-mail: mlucia@pppl.gov; Kaita, R.; Majeski, R.

The Materials Analysis and Particle Probe (MAPP) is a compact in vacuo surface science diagnostic, designed to provide in situ surface characterization of plasma facing components in a tokamak environment. MAPP has been implemented for operation on the Lithium Tokamak Experiment at Princeton Plasma Physics Laboratory (PPPL), where all control and analysis systems are currently under development for full remote operation. Control systems include vacuum management, instrument power, and translational/rotational probe drive. Analysis systems include onboard Langmuir probes and all components required for x-ray photoelectron spectroscopy, low-energy ion scattering spectroscopy, direct recoil spectroscopy, and thermal desorption spectroscopy surface analysis techniques.

Bicoherence Analysis of Electrostatic Interchange Mode Coupling in a Turbulent Laboratory Magnetosphere

NASA Astrophysics Data System (ADS)

Abler, M. C.; Mauel, M. E.; Saperstein, A.

2017-12-01

Plasmas confined by a strong dipole field exhibit interchange and entropy mode turbulence, which previous experiments have shown respond locally to active feedback [1]. On the Collisionless Terrella Experiment (CTX), this turbulence is characterized by low frequency, low order, quasi-coherent modes with complex spectral dynamics. We apply bicoherence analysis [2] to study nonlinear phase coupling in a variety of scenarios. First, we study the self-interaction of the naturally occurring interchange turbulence; this analysis is then expanded to include the effects of single or multiple driven modes in the frequency range of the background turbulent oscillations. Initial measurements of coupling coefficients are presented in both cases. Driven low frequency interchange modes are observed to generate multiple harmonics which persist throughout the plasma, becoming weaker as they propagate away from the actuator in the direction of the electron magnetic drift. Future work is also discussed, including application of wavelet bicoherence analysis and applications to planetary magnetospheres. [1] Roberts, Mauel, and Worstell, Phys Plasmas (2015). [2] Grierson, Worstell, and Mauel, Phys Plasmas (2009). Supported by NSF-DOE Partnership for Plasma Science Grants DOE-DE-FG02-00ER54585 and NSF-PHY-1201896.

Surface morphology changes to tungsten under exposure to He ions from an electron cyclotron resonance plasma source

NASA Astrophysics Data System (ADS)

Donovan, David; Maan, Anurag; Duran, Jonah; Buchenauer, Dean; Whaley, Josh

2015-11-01

Exposure of tungsten to low energy (<100 eV) helium plasmas at temperatures between 900-1900 K in both laboratory experiments and tokamaks has been shown to cause severe nanoscale modification of the near surface resulting the growth of tungsten tendrils. We used a relatively low flux (2.5x1019 ions m-2 s-1) compact ECR plasma source at Sandia-California to investigate the early stages of helium induced tungsten damage. Exposures of polished tungsten discs were performed and characterized using SEM, AFM, and FIB cross section imaging. Bubbles have been seen on the exposed tungsten surface and in sub-surface cross sections growing to up to 150 nm in diameter. Comparisons were made between exposures of warm rolled Plansee tungsten discs and ALMT ITER grade tungsten samples. A similar He plasma exposure stage has now been developed at the University of Tennessee-Knoxville with an improved compact ECR plasma source. Status of the new UTK exposure stage will be discussed as well as planned experiments and new material characterization techniques (EBSD, GIXRD). Work supported by US DOE Contract DE-AC04-94AL85000 and the PSI Science Center.

3D nonlinear numerical simulation of the current-convective instability in detached diverter plasma

NASA Astrophysics Data System (ADS)

Stepanenko, Alexander; Krasheninnikov, Sergei

2017-10-01

One of the possible mechanisms responsible for strong radiation fluctuations observed in the recent experiments with detached plasmas at ASDEX Upgrade [Potzel et al., Nuclear Fusion, 2014] can be related to the onset of the current-convective instability (CCI) driven by strong asymmetry of detachment in the inner and outer tokamak divertors [Krasheninnikov and Smolyakov, PoP, 2016]. In this study we present the first results of 3D nonlinear numerical simulations of the CCI in divertor plasma for the conditions relevant to the AUG experiment. The general physical model used to simulate the CCI, qualitative estimates for the instability characteristic growth rate and transverse wavelengths derived for plasma, which is spatially inhomogeneous both across and along the magnetic field lines, are presented. The simulation results, demonstrating nonlinear dynamics of the CCI, provide the frequency spectra of turbulent divertor plasma fluctuations showing good agreement with the available experimental data. This material is based upon the work supported by the U.S. Department of Energy under Award No. DE-FG02-04ER54739 at UCSD and by the Russian Ministry of Education and Science Grant No. 14.Y26.31.0008 at MEPhI.

Data reduction and analysis of HELIOS plasma wave data

NASA Technical Reports Server (NTRS)

Anderson, Roger R.

1988-01-01

Reduction of data acquired from the HELIOS Solar Wind Plasma Wave Experiments on HELIOS 1 and 2 was continued. Production of 24 hour survey plots of the HELIOS 1 plasma wave data were continued and microfilm copies were submitted to the National Space Science Data Center. Much of the effort involved the shock memory from both HELIOS 1 and 2. This data had to be deconvoluted and time ordered before it could be displayed and plotted in an organized form. The UNIVAX 418-III computer was replaced by a DEC VAX 11/780 computer. In order to continue the reduction and analysis of the data set, all data reduction and analysis computer programs had to be rewritten.

Tornado-like transport in a magnetized plasma

NASA Astrophysics Data System (ADS)

Poulos, Matthew; van Compernolle, Bart; Morales, George

2017-10-01

Recent heat transport experiments conducted in the LAPD device at UCLA in which avalanche events have been previously documented have also lead to the identification of a new tornado-like transport phenomenon. These tornados occur much earlier than the avalanches events, essentially in the interval following the application of the bias voltage that causes the injection of an electron beam from a ring-shaped LaB6 cathode into the afterglow of a cold, magnetized plasma. The tornados exhibit a low-frequency (4 kHz) (much lower than drift-waves), spiraling, global eigenmode whose transient behavior is responsible for significant radial transport well outside the heated region. Detailed experimental observations are compared with a Braginskii transport code that includes the effects of ExB convection induced by the spiraling global eigenmode. New insights are gained into the necessary modifications of classical transport to accurately simulate the spiraling effects and the possible interaction with avalanches. This work is supported by the NSF/DOE partnership in basic plasma science and engineering, Grant Number 1619505, and is performed at the Basic Plasma Science Facility, sponsored jointly by DOE and NSF. Sponsored by DOE/NSF at BaPSF and NSF 1619505.

High Voltage, Fast-Switching Module for Active Control of Magnetic Fields and Edge Plasma Currents

NASA Astrophysics Data System (ADS)

Ziemba, Timothy; Miller, Kenneth; Prager, James; Slobodov, Ilia

2016-10-01

Fast, reliable, real-time control of plasma is critical to the success of magnetic fusion science. High voltage and current supplies are needed to mitigate instabilities in all experiments as well as disruption events in large scale tokamaks for steady-state operation. Silicon carbide (SiC) MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities; however, these devices are limited to 1.2-1.7 kV devices. As fusion enters the long-pulse and burning plasma eras, efficiency of power switching will be important. Eagle Harbor Technologies (EHT), Inc. developing a high voltage SiC MOSFET module that operates at 10 kV. This switch module utilizes EHT gate drive technology, which has demonstrated the ability to increase SiC MOSFET switching efficiency. The module will allow more rapid development of high voltage switching power supplies at lower cost necessary for the next generation of fast plasma feedback and control. EHT is partnering with the High Beta Tokamak group at Columbia to develop detailed high voltage module specifications, to ensure that the final product meets the needs of the fusion science community.

Parametric Decay Instability of Near-Acoustic Waves in Fluid and Kinetic Regimes

NASA Astrophysics Data System (ADS)

Affolter, M.; Anderegg, F.; Driscoll, C. F.; Valentini, F.

2016-10-01

We present quantitative measurements of parametric wave-wave coupling rates and decay instabilities in the range 10 meV Δω /2. In contrast, at higher temperatures, the mz = 2 wave is more unstable. The instability threshold is reduced from the cold fluid prediction as the plasma temperature is increased, which is in qualitative agreement with Vlasov simulations, but is not yet understood theoretically. Supported by DOE/HEDLP Grant DE-SC0008693 and DOE Fusion Energy Science Postdoctoral Research Program administered by the Oak Ridge Institute for Science and Education.

Exciting Alfven Waves using Modulated Electron Heating by High Power Microwaves

NASA Astrophysics Data System (ADS)

Wang, Yuhou; Gekelman, Walter; Pribyl, Patrick; van Compernolle, Bart; Papadopoulos, Konstantinos

2014-10-01

Experiments exploring the physics of ionospheric modification with intense perpendicular propagating waves (k-> ⊥B->0) on the Large Plasma Device (LaPD) at UCLA have been upgraded with the addition of a high power rapidly pulsed microwave source. The plasma is irradiated with ten pulses (250 kW X-band) near the upper-hybrid frequency. The pulses are modulated at a frequency of a fraction (0.1-1.0) of fci (ion cyclotron frequency). Based on a previous single-pulse experiment, the modulated electron heating may drive a large amplitude shear Alfvén wave (f

Increase in plasma total antioxidant capacity of grazing Japanese Black heifers and cows in forestland in Japan.

PubMed

Haga, Satoshi; Ishizaki, Hiroshi; Nakano, Miwa; Nakao, Seiji; Hirano, Kiyoshi; Yamamoto, Yoshito; Kitagawa, Miya; Sasaki, Hiroyuki; Kariya, Yoshihiro

2014-02-01

Blood total antioxidant capacity (TAC) has become a key bio-marker for animal health. Forest-grazing cattle are known to forage various native plants that have high TAC. This study evaluated differences of plasma TAC between forest-grazing (FG) and pasture-grazing cattle (PG). Experiment 1 monitored the plasma TAC levels of 32 Japanese Black cattle. The level in PG did not change throughout the grazing period. However, that in FG, which increased from summer, was significantly higher than that in PG through fall (P < 0.05). In experiment 2, we used nine Japanese Black heifers and investigated their blood antioxidant parameters and the TAC in plants that the cattle consumed in late June and September. The plasma TAC levels in FG were significantly higher than those in PG in both periods (P < 0.05). Plasma levels of lipid peroxidation in FG tended to be lower than that in PG (P = 0.098). Furthermore, the TAC levels in various species of shrubs and trees consumed by FG were higher than those in pasture grasses. Results of this study show that plasma TAC of grazing Japanese Black cattle in forestland increase from summer through fall. © 2013 Japanese Society of Animal Science.

Plasma wakefield acceleration experiments at FACET II

NASA Astrophysics Data System (ADS)

Joshi, C.; Adli, E.; An, W.; Clayton, C. E.; Corde, S.; Gessner, S.; Hogan, M. J.; Litos, M.; Lu, W.; Marsh, K. A.; Mori, W. B.; Vafaei-Najafabadi, N.; O'shea, B.; Xu, Xinlu; White, G.; Yakimenko, V.

2018-03-01

During the past two decades of research, the ultra-relativistic beam-driven plasma wakefield accelerator (PWFA) concept has achieved many significant milestones. These include the demonstration of ultra-high gradient acceleration of electrons over meter-scale plasma accelerator structures, efficient acceleration of a narrow energy spread electron bunch at high-gradients, positron acceleration using wakes in uniform plasmas and in hollow plasma channels, and demonstrating that highly nonlinear wakes in the ‘blow-out regime’ have the electric field structure necessary for preserving the emittance of the accelerating bunch. A new 10 GeV electron beam facility, Facilities for Accelerator Science and Experimental Test (FACET) II, is currently under construction at SLAC National Accelerator Laboratory for the next generation of PWFA research and development. The FACET II beams will enable the simultaneous demonstration of substantial energy gain of a small emittance electron bunch while demonstrating an efficient transfer of energy from the drive to the trailing bunch. In this paper we first describe the capabilities of the FACET II facility. We then describe a series of PWFA experiments supported by numerical and particle-in-cell simulations designed to demonstrate plasma wake generation where the drive beam is nearly depleted of its energy, high efficiency acceleration of the trailing bunch while doubling its energy and ultimately, quantifying the emittance growth in a single stage of a PWFA that has optimally designed matching sections. We then briefly discuss other FACET II plasma-based experiments including in situ positron generation and acceleration, and several schemes that are promising for generating sub-micron emittance bunches that will ultimately be needed for both an early application of a PWFA and for a plasma-based future linear collider.

Plasma wakefield acceleration experiments at FACET II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joshi, C.; Adli, E.; An, W.

During the past two decades of research, the ultra-relativistic beam-driven plasma wakefield accelerator (PWFA) concept has achieved many significant milestones. These include the demonstration of ultra-high gradient acceleration of electrons over meter-scale plasma accelerator structures, efficient acceleration of a narrow energy spread electron bunch at high-gradients, positron acceleration using wakes in uniform plasmas and in hollow plasma channels, and demonstrating that highly nonlinear wakes in the 'blow-out regime' have the electric field structure necessary for preserving the emittance of the accelerating bunch. A new 10 GeV electron beam facility, Facilities for Accelerator Science and Experimental Test (FACET) II, is currentlymore » under construction at SLAC National Accelerator Laboratory for the next generation of PWFA research and development. The FACET II beams will enable the simultaneous demonstration of substantial energy gain of a small emittance electron bunch while demonstrating an efficient transfer of energy from the drive to the trailing bunch. In this paper we first describe the capabilities of the FACET II facility. We then describe a series of PWFA experiments supported by numerical and particle-in-cell simulations designed to demonstrate plasma wake generation where the drive beam is nearly depleted of its energy, high efficiency acceleration of the trailing bunch while doubling its energy and ultimately, quantifying the emittance growth in a single stage of a PWFA that has optimally designed matching sections. Here, we briefly discuss other FACET II plasma-based experiments including in situ positron generation and acceleration, and several schemes that are promising for generating sub-micron emittance bunches that will ultimately be needed for both an early application of a PWFA and for a plasma-based future linear collider.« less

Plasma wakefield acceleration experiments at FACET II

DOE PAGES

Joshi, C.; Adli, E.; An, W.; ...

2018-01-12

During the past two decades of research, the ultra-relativistic beam-driven plasma wakefield accelerator (PWFA) concept has achieved many significant milestones. These include the demonstration of ultra-high gradient acceleration of electrons over meter-scale plasma accelerator structures, efficient acceleration of a narrow energy spread electron bunch at high-gradients, positron acceleration using wakes in uniform plasmas and in hollow plasma channels, and demonstrating that highly nonlinear wakes in the 'blow-out regime' have the electric field structure necessary for preserving the emittance of the accelerating bunch. A new 10 GeV electron beam facility, Facilities for Accelerator Science and Experimental Test (FACET) II, is currentlymore » under construction at SLAC National Accelerator Laboratory for the next generation of PWFA research and development. The FACET II beams will enable the simultaneous demonstration of substantial energy gain of a small emittance electron bunch while demonstrating an efficient transfer of energy from the drive to the trailing bunch. In this paper we first describe the capabilities of the FACET II facility. We then describe a series of PWFA experiments supported by numerical and particle-in-cell simulations designed to demonstrate plasma wake generation where the drive beam is nearly depleted of its energy, high efficiency acceleration of the trailing bunch while doubling its energy and ultimately, quantifying the emittance growth in a single stage of a PWFA that has optimally designed matching sections. Here, we briefly discuss other FACET II plasma-based experiments including in situ positron generation and acceleration, and several schemes that are promising for generating sub-micron emittance bunches that will ultimately be needed for both an early application of a PWFA and for a plasma-based future linear collider.« less

Understanding Turbulence using Active and Passive Multipoint Measurements in Laboratory Magnetospheres

NASA Astrophysics Data System (ADS)

Mauel, M. E.; Abler, M. C.; Qian, T. M.; Saperstein, A.; Yan, J. R.

2017-10-01

In a laboratory magnetosphere, plasma is confined by a strong dipole magnet, and interchange and entropy mode turbulence can be studied and controlled in near steady-state conditions. Turbulence is dominated by long wavelength modes exhibiting chaotic dynamics, intermitency, and an inverse spectral cascade. Here, we summarize recent results: (i) high-resolution measurement of the frequency-wavenumber power spectrum using Capon's ``maximum likelihood method'', and (ii) direct measurement of the nonlinear coupling of interchange/entropy modes in a turbulent plasma through driven current injection at multiple locations and frequencies. These observations well-characterize plasma turbulence over a broad band of wavelengths and frequencies. Finally, we also discuss the application of these techniques to space-based experiments and observations aimed to reveal the nature of heliospheric and magnetospheric plasma turbulence. Supported by NSF-DOE Partnership in Plasma Science Grant DE-FG02-00ER54585.

Overview of theory and simulations in the Heavy Ion Fusion Science Virtual National Laboratory

NASA Astrophysics Data System (ADS)

Friedman, Alex

2007-07-01

The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) is a collaboration of Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and Princeton Plasma Physics Laboratory. These laboratories, in cooperation with researchers at other institutions, are carrying out a coordinated effort to apply intense ion beams as drivers for studies of the physics of matter at extreme conditions, and ultimately for inertial fusion energy. Progress on this endeavor depends upon coordinated application of experiments, theory, and simulations. This paper describes the state of the art, with an emphasis on the coordination of modeling and experiment; developments in the simulation tools, and in the methods that underly them, are also treated.

Radar investigation of barium releases over Arecibo Observatory, Puerto Rico. Final report, 12 August 1991-30 June 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Djuth, F.T.

1995-07-01

The NASA Combined Release and Radiation Effects Satellite (CRRES) El Coqui rocket campaign was successfully carried out in Puerto Rico during the period 18 May through 12 July 1992. This report describes five chemical release experiments in the upper ionosphere supported by Geospace Research, Inc. during the El Coqui campaign. Additional spin-off science is also discussed. The El Coqui releases are designated AA-1 (rocket 36-082), AA-2 (rocket 36-081), AA-3b (rocket 36-064), AA-4 (rocket 36-065), and AA-7 (rocket 36-083). Particular attention is paid to releases AA-2 and AA-4. These two experiments involved the illumination of ionospheric release regions with powerful high-frequencymore » (HF) radio waves transmitted from the Arecibo HF facility. In the AA-2 experiment, microinstabilities excited by the HF wave in a Ba(+) plasma were examined. This release yielded a smooth plasma cloud that helped clarify several fundamental issues regarding the physics of wave plasma instabilities. During AA-2 extremely strong HF-induced Langmuir turbulence was detected with the Arecibo 430 MHz radar. CF3Br was released in the AA-4 study to create an ionospheric hole that focused the HF beam. This experiment successfully explored wave-plasma coupling in an O(+) ionosphere under conditions of very high HF electric field strengths.« less

Town Meeting on Plasma Physics at the National Science Foundation

NASA Astrophysics Data System (ADS)

2015-11-01

We invite you to the Town Meeting on the role of the National Science Foundation (NSF) in supporting basic and applied research in Plasma Physics in the U.S. The overarching goal of NSF is to promote the progress of science and to enable training of the next generation of scientists and engineers at US colleges and universities. In this context, the role of the NSF Physics Division in leading the nearly 20 year old NSF/DOE Partnership in Basic Plasma Science and Engineering serves as an example of the long history of NSF support for basic plasma physics research. Yet, the NSF interest in maintaining a healthy university research base in plasma sciences extends across the Foundation. A total of five NSF Divisions are participating in the most recent Partnership solicitation, and a host of other multi-disciplinary and core programs provide opportunities for scientists to perform research on applications of plasma physics to Space & Solar Physics, Astrophysics, Accelerator Science, Material Science, Plasma Medicine, and many sub-disciplines within Engineering. This Town Meeting will provide a chance to discuss the full range of relevant NSF funding opportunities, and to begin a conversation on the present and future role of NSF in stewarding basic plasma science and engineering research at US colleges and universities. We would like to particularly encourage early career scientists and graduate students to participate in this Town Meeting, though everyone is invited to join what we hope to be a lively discussion.

The Effects of Temperature and Oxidation on Deuterium Retention in Solid and Liquid Lithium Films on Molybdenum Plasma-Facing Components

NASA Astrophysics Data System (ADS)

Capece, Angela

2014-10-01

Liquid metal plasma-facing components (PFCs) enable in-situ renewal of the surface, thereby offering a solution to neutron damage, erosion, and thermal fatigue experienced by solid PFCs. Lithium in particular has a high chemical affinity for hydrogen, which has resulted in reduced recycling and enhanced plasma performance on many fusion devices including TFTR, T11-M, FTU, CDX-U, LTX, TJ-II, and NSTX. A key component to the improvement in plasma performance is deuterium retention in Li; however, this process is not well understood in the complex tokamak environment. Recent surface science experiments conducted at the Princeton Plasma Physics Laboratory have used electron spectroscopy and temperature programmed desorption to understand the mechanisms for D retention in Li coatings on Mo substrates. The experiments were designed to give monolayer-control of Li films and were conducted in ultrahigh vacuum under controlled environments. An electron cyclotron resonance plasma source was used to deliver a beam of deuterium ions to the surface over a range of ion energies. Our work shows that D is retained as LiD in metallic Li films. However, when oxygen is present in the film, either by diffusion from the subsurface at high temperature or as a contaminant during the deposition process, Li oxides are formed that retain D as LiOD. Experiments indicate that LiD is more thermally stable than LiOD, which decomposes to liberate D2 gas and D2O at temperatures 100 K lower than the LiD decomposition temperature. Other experiments show how D retention varies with substrate temperature to provide insight into the differences between solid and liquid lithium films. This work was supported by DOE Contract No. DE AC02-09CH11466.

The 2017 Plasma Roadmap: Low temperature plasma science and technology

USDA-ARS?s Scientific Manuscript database

Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic upd...

The Giotto radio-science experiment

NASA Technical Reports Server (NTRS)

Edenhofer, P.; Bird, M. K.; Buschert, H.; Esposito, P. B.; Porsche, H.; Volland, H.

1986-01-01

The scientific objectives of the Giotto Radio Science Experiment (GRE) are to determine the columnar electron content of Comet Halley/s ionosphere and the cometary mass fluence from atmospheric drag by using the radio signals from Giotto during the Halley encounter. The radio science data (S and X-band Doppler and range measurements) will be collected at NASA/s deep-space 64 m tracking antenna at Tidbinbilla near Canberra, in Australia. In order to separate the effects of the terrestrial ionosphere and the interplanetary plasma, S-band Doppler measurements will also be taken at Tidbinbilla along the line-of-sight of Japan/s cometary probe Sakigake during the Giotto-Halley Encounter. The measurements of cometary electron content and mass fluence will be inverted to derive the spatial distribution of the electron and mass (dust and gas) density within Halley/s coma. The GRE is the only experiment on Giotto capable of measuring the low-energy (10 eV) electron bulk population of Halley/s ionosphere and the total cometary mass flow impacting upon the spacecraft.

Numerical and Experimental Investigation on the Attenuation of Electromagnetic Waves in Unmagnetized Plasmas Using Inductively Coupled Plasma Actuator

NASA Astrophysics Data System (ADS)

Lin, Min; Xu, Haojun; Wei, Xiaolong; Liang, Hua; Song, Huimin; Sun, Quan; Zhang, Yanhua

2015-10-01

The attenuation of electromagnetic (EM) waves in unmagnetized plasma generated by an inductively coupled plasma (ICP) actuator has been investigated both theoretically and experimentally. A numerical study is conducted to investigate the propagation of EM waves in multilayer plasma structures which cover a square flat plate. Experimentally, an ICP actuator with dimensions of 20 cm×20 cm×4 cm is designed to produce a steady plasma slab. The attenuation of EM waves in the plasma generated by the ICP actuator is measured by a reflectivity arch test method at incident waves of 2.3 GHz and 10.1 GHz, respectively. A contrastive analysis of calculated and measured results of these incident wave frequencies is presented, which suggests that the experiment accords well with our theory. As expected, the plasma slab generated by the ICP actuator can effectively attenuate the EM waves, which may have great potential application prospects in aircraft stealth. supported by National Natural Science Foundation of China (Nos. 51276197, 11472306 and 11402301)

PREFACE: 26th Symposium on Plasma Science for Materials (SPSM-26)

NASA Astrophysics Data System (ADS)

2014-06-01

26th Symposium on Plasma Science for Materials (SPSM-26) Takayuki Watanabe The 26th Symposium on Plasma Science for Materials (SPSM-26) was held in Fukuoka, Japan on September 23-24, 2013. SPSM has been held annually since 1988 under the sponsorship of The 153rd Committee on Plasma Materials Science, Japan Society for the Promotion of Science (JSPS). This symposium is one of the major activities of the Committee, which is organized by researchers in academia and industry for the purpose of advancing intersectional scientific information exchange and discussion of science and technology of plasma materials processing. Plasma processing have attracted extensive attention due to their unique advantages, and it is expected to be utilized for a number of innovative industrial applications such as synthesis of high-quality and high-performance nanomaterials. The advantages of plasmas including high chemical reactivity in accordance with required chemical reactions are beneficial for innovative processing. In recent years, plasma materials processing with reactive plasmas has been extensively employed in the fields of environmental issues and biotechnology. This conference seeks to bring different scientific communities together to create a forum for discussing the latest developments and issues. The conference provides a platform for the exploration of both fundamental topics and new applications of plasmas by the contacts between science, technology, and industry. The conference was organized in plenary lectures, invited, contributed oral presentations, and poster sessions. At this meeting, we had 142 participants from 10 countries and 104 presentations, including 11 invited presentations. This year, we arranged special topical sessions that cover Plasma Medicine and Biotechnologies, Business and Academia Cooperation, Plasma with Liquids, Plasma Processes for Nanomaterials, together with Basic, Electronics, and Thermal Plasma sessions. This special issue presents 28 papers that are selected via strict peer-review process from full papers submitted for the proceedings of the conference. The topics range from basic physics and chemistry of plasma processing to a broad variety of materials processing and environmental applications. This proceeding offers an overview on the recent advances in thermal and non-equilibrium plasmas as well as the challenges ahead in the field of plasma research and applications among engineers and scientists. It is an honor to present this volume of Journal of Physics: Conference Series and we deeply thank the authors for their enthusiastic and high-grade contribution. The editors hope that this proceeding will be useful and helpful for deepening our understanding of science and technology of plasma materials processing and also for stimulating further development of the plasma technology. Finally, I would like to thank the organizing committee and organizing secretariat of SPSM-26, and the participants of the conference for contribution to a successful and exciting meeting. The conference was chaired by Prof. Masaharu Shiratani, Kyushu University. I would also like to thank the financial support from The 153rd Committee on Plasma Materials Science. Editors of SPMS-26 Prof Takayuki Watanabe, Kyushu University, Japan Prof Makoto Sekine, Nagoya University, Japan Prof Takanori Ichiki, The University of Tokyo, Japan Prof Masaharu Shiratani, Kyushu University, Japan Prof Akimitsu Hatta, Kochi University of Technology, Japan Sponsors and Supporting Organization: The 153rd Committee on Plasma Materials Science, Japan Society for the Promotion of Science

Advances in boronization on NSTX-Upgrade

DOE PAGES

Skinner, C. H.; Bedoya, F.; Scotti, F.; ...

2017-01-27

Boronization has been effective in reducing plasma impurities and enabling access to higher density, higher confinement plasmas in many magnetic fusion devices. The National Spherical Torus eXperiment, NSTX, has recently undergone a major upgrade to NSTX-U in order to develop the physics basis for a ST-based Fusion Nuclear Science Facility (FNSF) with capability for double the toroidal field, plasma current, and NBI heating power and increased pulse duration from 1–1.5 s to 5–8 s. A new deuterated tri-methyl boron conditioning system was implemented together with a novel surface analysis diagnostic. We report on the spatial distribution of the boron depositionmore » versus discharge pressure, gas injection and electrode location. The oxygen concentration of the plasma facing surface was measured by in-vacuo XPS and increased both with plasma exposure and with exposure to trace residual gases. Furthermore, this increase correlated with the rise of oxygen emission from the plasma.« less

PSI-Center Simulations of Validation Platform Experiments

NASA Astrophysics Data System (ADS)

Nelson, B. A.; Akcay, C.; Glasser, A. H.; Hansen, C. J.; Jarboe, T. R.; Marklin, G. J.; Milroy, R. D.; Morgan, K. D.; Norgaard, P. C.; Shumlak, U.; Victor, B. S.; Sovinec, C. R.; O'Bryan, J. B.; Held, E. D.; Ji, J.-Y.; Lukin, V. S.

2013-10-01

The Plasma Science and Innovation Center (PSI-Center - http://www.psicenter.org) supports collaborating validation platform experiments with extended MHD simulations. Collaborators include the Bellan Plasma Group (Caltech), CTH (Auburn U), FRX-L (Los Alamos National Laboratory), HIT-SI (U Wash - UW), LTX (PPPL), MAST (Culham), Pegasus (U Wisc-Madison), PHD/ELF (UW/MSNW), SSX (Swarthmore College), TCSU (UW), and ZaP/ZaP-HD (UW). Modifications have been made to the NIMROD, HiFi, and PSI-Tet codes to specifically model these experiments, including mesh generation/refinement, non-local closures, appropriate boundary conditions (external fields, insulating BCs, etc.), and kinetic and neutral particle interactions. The PSI-Center is exploring application of validation metrics between experimental data and simulations results. Biorthogonal decomposition is proving to be a powerful method to compare global temporal and spatial structures for validation. Results from these simulation and validation studies, as well as an overview of the PSI-Center status will be presented.

Developing the science and technology for the Material Plasma Exposure eXperiment

NASA Astrophysics Data System (ADS)

Rapp, J.; Biewer, T. M.; Bigelow, T. S.; Caneses, J. F.; Caughman, J. B. O.; Diem, S. J.; Goulding, R. H.; Isler, R. C.; Lumsdaine, A.; Beers, C. J.; Bjorholm, T.; Bradley, C.; Canik, J. M.; Donovan, D.; Duckworth, R. C.; Ellis, R. J.; Graves, V.; Giuliano, D.; Green, D. L.; Hillis, D. L.; Howard, R. H.; Kafle, N.; Katoh, Y.; Lasa, A.; Lessard, T.; Martin, E. H.; Meitner, S. J.; Luo, G.-N.; McGinnis, W. D.; Owen, L. W.; Ray, H. B.; Shaw, G. C.; Showers, M.; Varma, V.; the MPEX Team

2017-11-01

Linear plasma generators are cost effective facilities to simulate divertor plasma conditions of present and future fusion reactors. They are used to address important R&D gaps in the science of plasma material interactions and towards viable plasma facing components for fusion reactors. Next generation plasma generators have to be able to access the plasma conditions expected on the divertor targets in ITER and future devices. The steady-state linear plasma device MPEX will address this regime with electron temperatures of 1-10 eV and electron densities of 1021{\\text{}}-1020 m-3 . The resulting heat fluxes are about 10 MW m-2 . MPEX is designed to deliver those plasma conditions with a novel Radio Frequency plasma source able to produce high density plasmas and heat electron and ions separately with electron Bernstein wave (EBW) heating and ion cyclotron resonance heating with a total installed power of 800 kW. The linear device Proto-MPEX, forerunner of MPEX consisting of 12 water-cooled copper coils, has been operational since May 2014. Its helicon antenna (100 kW, 13.56 MHz) and EC heating systems (200 kW, 28 GHz) have been commissioned and 14 MW m-2 was delivered on target. Furthermore, electron temperatures of about 20 eV have been achieved in combined helicon and ECH heating schemes at low electron densities. Overdense heating with EBW was achieved at low heating powers. The operational space of the density production by the helicon antenna was pushed up to 1.1 × 1020 m-3 at high magnetic fields of 1.0 T at the target. The experimental results from Proto-MPEX will be used for code validation to enable predictions of the source and heating performance for MPEX. MPEX, in its last phase, will be capable to expose neutron-irradiated samples. In this concept, targets will be irradiated in ORNL’s High Flux Isotope Reactor and then subsequently exposed to fusion reactor relevant plasmas in MPEX.

A survey of dusty plasma physics

NASA Astrophysics Data System (ADS)

Shukla, P. K.

2001-05-01

Two omnipresent ingredients of the Universe are plasmas and charged dust. The interplay between these two has opened up a new and fascinating research area, that of dusty plasmas, which are ubiquitous in different parts of our solar system, namely planetary rings, circumsolar dust rings, the interplanetary medium, cometary comae and tails, as well as in interstellar molecular clouds, etc. Dusty plasmas also occur in noctilucent clouds in the arctic troposphere and mesosphere, cloud-to-ground lightening in thunderstorms containing smoke-contaminated air over the United States, in the flame of a humble candle, as well as in microelectronic processing devices, in low-temperature laboratory discharges, and in tokamaks. Dusty plasma physics has appeared as one of the most rapidly growing fields of science, besides the field of the Bose-Einstein condensate, as demonstrated by the number of published papers in scientific journals and conference proceedings. In fact, it is a truly interdisciplinary science because it has many potential applications in astrophysics (viz. in understanding the formation of dust clusters and structures, instabilities of interstellar molecular clouds and star formation, decoupling of magnetic fields from plasmas, etc.) as well as in the planetary magnetospheres of our solar system [viz. Saturn (particularly, the physics of spokes and braids in the B and F rings), Jupiter, Uranus, Neptune, and Mars] and in strongly coupled laboratory dusty plasmas. Since a dusty plasma system involves the charging and dynamics of massive charged dust grains, it can be characterized as a complex plasma system providing new physics insights. In this paper, the basic physics of dusty plasmas as well as numerous collective processes are discussed. The focus will be on theoretical and experimental observations of charging processes, waves and instabilities, associated forces, the dynamics of rotating and elongated dust grains, and some nonlinear structures (such as dust ion-acoustic shocks, Mach cones, dust voids, vortices, etc). The latter are typical in astrophysical settings and in several laboratory experiments. It appears that collective processes in a complex dusty plasma would have excellent future perspectives in the twenty-first century, because they have not only potential applications in interplanetary space environments, or in understanding the physics of our universe, but also in advancing our scientific knowledge in multidisciplinary areas of science.

Comparing nonlinear MHD simulations of low-aspect-ratio RFPs to RELAX experiments

NASA Astrophysics Data System (ADS)

McCollam, K. J.; den Hartog, D. J.; Jacobson, C. M.; Sovinec, C. R.; Masamune, S.; Sanpei, A.

2016-10-01

Standard reversed-field pinch (RFP) plasmas provide a nonlinear dynamical system as a validation domain for numerical MHD simulation codes, with applications in general toroidal confinement scenarios including tokamaks. Using the NIMROD code, we simulate the nonlinear evolution of RFP plasmas similar to those in the RELAX experiment. The experiment's modest Lundquist numbers S (as low as a few times 104) make closely matching MHD simulations tractable given present computing resources. Its low aspect ratio ( 2) motivates a comparison study using cylindrical and toroidal geometries in NIMROD. We present initial results from nonlinear single-fluid runs at S =104 for both geometries and a range of equilibrium parameters, which preliminarily show that the magnetic fluctuations are roughly similar between the two geometries and between simulation and experiment, though there appear to be some qualitative differences in their temporal evolution. Runs at higher S are planned. This work is supported by the U.S. DOE and by the Japan Society for the Promotion of Science.

XFEL resonant photo-pumping of dense plasmas and dynamic evolution of autoionizing core hole states

NASA Astrophysics Data System (ADS)

Rosmej, F. B.; Moinard, A.; Renner, O.; Galtier, E.; Lee, J. J.; Nagler, B.; Heimann, P. A.; Schlotter, W.; Turner, J. J.; Lee, R. W.; Makita, M.; Riley, D.; Seely, J.

2016-03-01

Similarly to the case of LIF (Laser-Induced Fluorescence), an equally revolutionary impact to science is expected from resonant X-ray photo-pumping. It will particularly contribute to a progress in high energy density science: pumped core hole states create X-ray transitions that can escape dense matter on a 10 fs-time scale without essential photoabsorption, thus providing a unique possibility to study matter under extreme conditions. In the first proof of principle experiment at the X-ray Free Electron Laser LCLS at SCLAC [Seely, J., Rosmej, F.B., Shepherd, R., Riley, D., Lee, R.W. Proposal to Perform the 1st High Energy Density Plasma Spectroscopic Pump/Probe Experiment”, approved LCLS proposal L332 (2010)] we have successfully pumped inner-shell X-ray transitions in dense plasmas. The plasma was generated with a YAG laser irradiating solid Al and Mg targets attached to a rotating cylinder. In parallel to the optical laser beam, the XFEL was focused into the plasma plume at different delay times and pump energies. Pumped X-ray transitions have been observed with a spherically bent crystal spectrometer coupled to a Princeton CCD. By using this experimental configuration, we have simultaneously achieved extremely high spectral (λ/δλ ≈ 5000) and spatial resolution (δx≈70 μm) while maintaining high luminosity and a large spectral range covered (6.90 - 8.35 Å). By precisely measuring the variations in spectra emitted from plasma under action of XFEL radiation, we have successfully demonstrated transient X- ray pumping in a dense plasma.

Magnetospheric Multiscale Mission Micrometeoroid/Orbital Debris Impacts

NASA Technical Reports Server (NTRS)

Williams, Trevor; Sedlak, Joseph; Shulman, Seth

2017-01-01

The MMS spacecraft are highly instrumented (accelerometers, star cameras, Sun sensors, science experiments for plasmas etc.). This presentation will discuss how data from these systems has allowed two micrometeoroid/orbital debris events to be studied: the Feb. 2, 2016 impact with an MMS4 shunt resistor, and the June 12, 2016 impact with an MMS4 wire boom.

Science & Technology Review September 2005

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aufderheide III, M B

2005-07-19

This month's issue has the following articles: (1) The Pursuit of Fusion Energy--Commentary by William H. Goldstein; (2) A Dynamo of a Plasma--The self-organizing magnetized plasmas in a Livermore fusion energy experiment are akin to solar flares and galactic jets; (3) How One Equation Changed the World--A three-page paper by Albert Einstein revolutionized physics by linking mass and energy; (4) Recycled Equations Help Verify Livermore Codes--New analytic solutions for imploding spherical shells give scientists additional tools for verifying codes; and (5) Dust That.s Worth Keeping--Scientists have solved the mystery of an astronomical spectral feature in interplanetary dust particles.

Effects of Density and Impurity on Edge Localized Modes in Tokamaks

NASA Astrophysics Data System (ADS)

Zhu, Ping

2017-10-01

Plasma density and impurity concentration are believed to be two of the key elements governing the edge tokamak plasma conditions. Optimal levels of plasma density and impurity concentration in the edge region have been searched for in order to achieve the desired fusion gain and divertor heat/particle load mitigation. However, how plasma density or impurity would affect the edge pedestal stability may have not been well known. Our recent MHD theory modeling and simulations using the NIMROD code have found novel effects of density and impurity on the dynamics of edge-localized modes (ELMs) in tokamaks. First, previous MHD analyses often predict merely a weak stabilizing effect of toroidal flow on ELMs in experimentally relevant regimes. We find that the stabilizing effects on the high- n ELMs from toroidal flow can be significantly enhanced with the increased edge plasma density. Here n denotes the toroidal mode number. Second, the stabilizing effects of the enhanced edge resistivity due to lithium-conditioning on the low- n ELMs in the high confinement (H-mode) discharges in NSTX have been identified. Linear stability analysis of the experimentally constrained equilibrium suggests that the change in the equilibrium plasma density and pressure profiles alone due to lithium-conditioning may not be sufficient for a complete suppression of the low- n ELMs. The enhanced resistivity due to the increased effective electric charge number Zeff after lithium-conditioning provides additional stabilization of the low- n ELMs. These new effects revealed in our theory analyses may help further understand recent ELM experiments and suggest new control schemes for ELM suppression and mitigation in future experiments. They may also pose additional constraints on the optimal levels of plasma density and impurity concentration in the edge region for H-mode tokamak operation. Supported by National Magnetic Confinement Fusion Science Program of China Grants 2014GB124002 and 2015GB101004, the 100 Talent Program of the Chinese Academy of Sciences, and U.S. Department of Energy Grants DE-FG02-86ER53218 and DE-FC02-08ER54975.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finley, V.L. and Levine, J.D.

The results of the 1997 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants, if any, that are added to the environment as a result of PPPL's operations. During Calendar Year 1997, PPPL's Tokamak Fusion Test Reactor (TFTR) completed fifteen years of fusion experiments begun in 1982. Over the course of three and half years of deuterium-tritium (D-T) plasma experiments, PPPL set a world record of 10.7more » million watts of controlled fusion power, more than 700 tritium shots pulsed into the reactor vessel generating more than 5.6 x 10 20 neutron and 1.6 gigajoules of fusion energy and researchers studied plasma science experimental data, which included "enhanced reverse shear techniques." As TFTR was completing its historic operations, PPPL participated with the Oak Ridge National Laboratory, Columbia University, and the University of Washington (Seattle) in a collaboration effort to design the National Spherical Torus Experiment (NSTX). This next device, NSTX, is located in the former TFTR Hot Cell on D site, and it is designed to be a smaller and more economical torus fusion reactor. Construction of this device began in late 1997, and first plasma in scheduled for early 1999. For 1997, the U.S. Department of Energy in its Laboratory Appraisal report rated the overall performance of Princeton Plasma Physics Laboratory as "excellent." The report cited the Laboratory's consistently excellent scientific and technological achievements and its successful management practices, which included high marks for environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an adjacent area to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.« less

The Transport of Solar Ions Through the Earth's Magnetosphere

NASA Technical Reports Server (NTRS)

Lennartsson, O. W.

1999-01-01

This report covers the initial phase of an investigation that was originally selected by NASA Headquarters for funding by a grant but was later transferred to NASA GSFC for continued funding under a new and separate contract. The principal objective of the investigation, led by Dr. O.W. Lennartsson, is to extract information about the solar origin plasma in Earth's magnetosphere, specifically about the entry and transport of this plasma, using energetic (10 eV/e to 18 keV/e) ion composition data from the Lockheed Plasma Composition Experiment on the NASA/ESA International Sun-Earth Explorer One (ISEE 1) satellite. These data were acquired many years ago, from November 1977 through March of 1982, but, because of subsequent failures of similar experiments on several other spacecraft, they are still the only substantial ion composition data available from Earth's magnetotail, beyond 10 R(sub E), in the critically important sub-kev to keV energy range. All of the Lockheed data now exist in a compacted scientific format, suitable for large-scale statistical investigations, which has been archived both at Lockheed Martin in Palo Alto and at the National Space Science Data Center (NSSDC) in Greenbelt. The completion of the archiving, by processing the remaining half of the data, was made possible by separate funding through a temporary NASA program for data restoration and was given priority over the data analysis by a no-cost extension of the subject grant. By chance, the period of performance coincided with an international study of source and loss processes of magnetospheric plasma, sponsored by the International Space Science Institute (ISSI) in Bern, Switzerland, for which Dr. Lennartsson was invited to serve as one of 12 co-chairs. This study meshed well with the continued analysis of the NASA/Lockheed ISEE ion composition data and provided a natural forum for a broader discussion of the results from this unique experiment. What follows is arranged, for the most part, in the context of the ISSI project.

PREFACE: 11th Asia-Pacific Conference on Plasma Science and Technology (APCPST-11) and 25th Symposium on Plasma Science for Materials (SPSM-25)

NASA Astrophysics Data System (ADS)

Watanabe, Takayuki; Kaneko, Toshio; Sekine, Makoto; Tanaka, Yasunori

2013-06-01

The 11th Asia-Pacific Conference on Plasma Science and Technology (APCPST-11) was held in Kyoto, Japan on 2-5 October 2012 with the 25th Symposium on Plasma Science for Materials (SPSM-25). SPSM has been held annually since 1988 under the sponsorship of The 153rd Committee on Plasma Materials Science, Japan Society for the Promotion of Science (JSPS). This symposium is one of the major activities of the Committee, which is organized by researchers in academia and industry for the purpose of advancing intersectional scientific information exchange and discussion of science and technology of plasma materials processing. APCPST and SPSM are jointly held biennially to survey the current status of low temperature and thermal plasma physics and chemistry for industrial applications. The whole area of plasma processing was covered from fundamentals to applications. Previous meetings were held in China, Japan, Korea, and Australia, attended by scientists from the Asia-Pacific and other countries. The joint conference was organized in plenary lectures, invited, contributed oral presentations and poster sessions. At this meeting, we had 386 participants from 10 countries and 398 presentations, including 26 invited presentations. This year, we arranged special topical sessions that covered green innovation, life innovation, and technical reports from industry. This conference seeks to bring the plasma community together and to create a forum for discussing the latest developments and issues, the challenges ahead in the field of plasma research and applications among engineers and scientists in Asia, the Pacific Rim, as well as Europe. This volume presents 44 papers that were selected via a strict peer-review process from full papers submitted for the proceedings of the conference. The topics range from the basic physics and chemistry of plasma processing to a broad variety of materials processing and environmental applications. This volume offers an overview of recent advances in thermal and non-equilibrium plasmas as well as on more new and innovative developments in the field of life innovation, green innovation and a technical report session. The editors hope that this volume will be useful and helpful for deepening our understanding of science and technology of plasma materials processing and also for stimulating further development of the plasma technology. Finally, we would like to thank the conference chairmen, the members of the organizing committee, the advisory committee, the executive committee, the program committee, the publication committee, organizing secretariat and financial support from The 153rd Committee on Plasma Materials Science, JSPS. Sponsors and Supporting Organization: The 153rd Committee on Plasma Materials Science, Japan Society for the Promotion of Science Organizing Committee Chairperson: Osamu Tsuji, SAMCO Corporation, Japan Advisory Committee Chairperson: Akihisa Matsuda, Osaka University, Japan Executive Committee Chairperson: Masaru Hori, Nagoya University, Japan Program Committee Chairperson: Takamasa Ishigaki, Hosei University, Japan Publication Committee Chairperson: Takayuki Watanabe, Kyushu University Editors of APCPST-11 and SPMS-25 Professor Takayuki Watanabe, Kyushu University, Japan Professor Toshio Kaneko, Tohoku University, Japan Professor Makoto Sekine, Nagoya University, Japan Professor Yasunori Tanaka, Kanazawa University, Japan

A 160 kJ dual plasma focus (DuPF) for fusion-relevant materials testing and nano-materials fabrication

NASA Astrophysics Data System (ADS)

Saw, S. H.; Damideh, V.; Chong, P. L.; Lee, P.; Rawat, R. S.; Lee, S.

2014-08-01

This paper summarizes PF-160 Dual Plasma Focus (DuPF) numerical experiments using the Lee Model code and preliminary 3D design drawings using SolidWorks software. This DuPF consists of two interchangeable electrodes enabling it to be optimized for both Slow Pinch Mode (SFM) and Fast Pinch Mode (FFM); the latter using a speed factor (SF) of 90 kA cm-1 Torr-0.5 for FFM in deuterium [S Lee et al, IEEE Trans Plasma Science 24, 1101-1105 (1996)]; and the former with SF of less than half that value for SFM. Starting with available 6 × 450 µF capacitors rated at 11kV (10% reversal), numerical experiments indicate safe operation at 9 kV, 6 Torr deuterium with FFM anode of 5 cm radius; producing intense ion beam and streaming plasma pulses which would be useful for studies of potential fusion reactor wall materials. On the other hand operating at 5 kV, 10 Torr deuterium with SFM anode of 10 cm radius leads to long-duration, uniform large-area flow which could be more suitable for synthesis of nano-materials. The dual plasma focus design is illustrated here with two figures showing FFM and SFM electrodes.

New Frontier Science Campaign on DIII-D launched in 2017

NASA Astrophysics Data System (ADS)

Koepke, M.; Buttery, R.; Carter, T.; Egedal, J.; Forest, C.; Fox, W.; Ji, H.; Howes, G.; Piovesan, P.; Sarff, J.; Skiff, F.; Spong, D.; DIII-D FSE Collaboration Collaboration

2017-10-01

The DIII-D Frontier Science Experiments initiative explores the potential to use the DIII-D tokamak facility to investigate questions of value beyond the usual fusion-energy science mission of DIII-D. The campaign is unique within DOE-SC-FES because the DIII-D tokamak supplied a multi-day-shot platform for non-fusion-energy-motivated research for the first time. All selected FSE campaign projects competed on the basis of potential intellectual impact and on the degree to which the ability to achieve success as a transformational advance relied on the capabilities of DIII-D. The motivation of the following FSE projects, as well as the selection process, will be summarized (1) Self-organization of Unstable Flux Ropes: Universal Structures in Space/Astrophysical Plasmas (2) Impact of Magnetic Perturbations on Turbulence: Zonal Flow Interactions and Saturation (3) Interaction of Alfvén/whistler fluctuations and Runaway Electrons (4) Self-consistent chaos in magnetic field dynamics These basic-plasma experiments, conducted in collaboration with the DIII-D team, were carried out during 5 shot days in FY2017. Additional days are earmarked in FY2018. Future studies with additional FSE-community members are envisioned. Opportunities exist to piggy back with DIII-D research A proper solicitation and peer review would be appropriate going forward if this activity on DIII-D continues Funding from U.S. DOE is gratefully acknowledged.

Space-Charge Effect on Residual Energy Under Intense Ultrashort Pulse Laser

NASA Astrophysics Data System (ADS)

Chen, Shi-gang; Wang, You-qin; Nie, Xiaebo

1996-12-01

Can the space-charge effect reduce the above-threshold-ionization (ATI) energy? This problem is analyzed by using the technique of multiple-time-scale perturbation. As the optical frequency is much larger than the plasma frequency, the space-charge effect is then reduced to the ponderomotive effect. It is found that the ponderomotive effect on residual energy is great as half plasma period is larger than pulse length, however, it cannot reduce the ATI energy over the whole density range. The relevant experiments are analyzed. Their results support our conclusions. Finally, it is pointed out that for a given pulse laser there may be a density range available for optical field ionization x-ray laser over which only the ATI heating plays role. The project supported by the National Natural Science Foundation of China and the Science Foundation of the Chinese Academy of Engineering Physics

Intense Plasma Waveguide Terahertz Sources for High-Field THz Probe Science with Ultrafast Lasers for Solid State Physics

DTIC Science & Technology

2016-08-25

AFRL-AFOSR-UK-TR-2016-0029 Intense Plasma-Waveguide Terahertz Sources for High-Field THz probe science with ultrafast lasers for Solid State Physics...Plasma-Waveguide Terahertz Sources for High-Field THz probe science with ultrafast lasers for Solid State Physics, 5a.  CONTRACT NUMBER 5b.  GRANT...an existing high energy laser system, has been applied to the study of intense terahertz radiation generated in gaseous plasmas in purpose

Educational Outreach at the M.I.T. Plasma Fusion Center

NASA Astrophysics Data System (ADS)

Censabella, V.

1996-11-01

Educational outreach at the MIT Plasma Fusion Center consists of volunteers working together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PFC holds a number of outreach activities throughout the year, such as Middle and High School Outreach Days. Outreach also includes the Mr. Magnet Program, which uses an interactive strategy to engage elementary school children. Included in this year's presentation will be a new and improved C-MOD Jr, a confinement video game which helps students to discover how computers manipulate magnetic pulses to keep a plasma confined for as long as possible. Also on display will be an educational toy created by the Cambridge Physics Outlet, a PFC spin-off company. The PFC maintains a Home Page on the World Wide Web, which can be reached at http://cmod2.pfc.mit.edu/.

Measurement of vertical stability metrics in KSTAR

NASA Astrophysics Data System (ADS)

Hahn, Sang-Hee; Humphreys, D. A.; Mueller, D.; Bak, J. G.; Eidietis, N. W.; Kim, H.-S.; Ko, J. S.; Walker, M. L.; Kstar Team

2017-10-01

The paper summarizes results of multi-year ITPA experiments regarding measurement of the vertical stabilization capability of KSTAR discharges, including most recent measurements at the highest achievable elongation (κ 2.0 - 2.1). The measurements of the open-loop growth rate of VDE (γz) and the maximum controllable vertical displacement (ΔZmax) are done by the release-and-catch method. The dynamics of the vertical movement of the plasma is verified by both relevant magnetic reconstructions and non-magnetic diagnostics. The measurements of γz and ΔZmax were done for different plasma currents, βp, internal inductances, elongations and different configurations of the vessel conductors that surround the plasma as the first wall. Effects of control design choice and diagnostics noise are discussed, and comparison with the axisymmetric plasma response model is given for partial accounting for the measured control capability. This work supported by Ministry of Science, ICT, and Future Planning under KSTAR project.

Relaunch of the Interactive Plasma Physics Educational Experience (IPPEX)

NASA Astrophysics Data System (ADS)

Dominguez, A.; Rusaitis, L.; Zwicker, A.; Stotler, D. P.

2015-11-01

In the late 1990's PPPL's Science Education Department developed an innovative online site called the Interactive Plasma Physics Educational Experience (IPPEX). It featured (among other modules) two Java based applications which simulated tokamak physics: A steady state tokamak (SST) and a time dependent tokamak (TDT). The physics underlying the SST and the TDT are based on the ASPECT code which is a global power balance code developed to evaluate the performance of fusion reactor designs. We have relaunched the IPPEX site with updated modules and functionalities: The site itself is now dynamic on all platforms. The graphic design of the site has been modified to current standards. The virtual tokamak programming has been redone in Javascript, taking advantage of the speed and compactness of the code. The GUI of the tokamak has been completely redesigned, including more intuitive representations of changes in the plasma, e.g., particles moving along magnetic field lines. The use of GPU accelerated computation provides accurate and smooth visual representations of the plasma. We will present the current version of IPPEX as well near term plans of incorporating real time NSTX-U data into the simulation.

Current fundamental science challenges in low temperature plasma science that impact energy security and international competitiveness

NASA Astrophysics Data System (ADS)

Hebner, Greg

2010-11-01

Products and consumer goods that utilize low temperature plasmas at some point in their creation touch and enrich our lives on almost a continuous basis. Examples are many but include the tremendous advances in microelectronics and the pervasive nature of the internet, advanced material coatings that increase the strength and reliability of products from turbine engines to potato chip bags, and the recent national emphasis on energy efficient lighting and compact fluorescent bulbs. Each of these products owes their contributions to energy security and international competiveness to fundamental research investments. However, it would be a mistake to believe that the great commercial success of these products implies a robust understanding of the complicated interactions inherent in plasma systems. Rather, current development of the next generation of low temperature plasma enabled products and processes is clearly exposing a new set of exciting scientific challenges that require leaps in fundamental understanding and interdisciplinary research teams. Emerging applications such as liquid-plasma systems to improve water quality and remediate hazardous chemicals, plasma-assisted combustion to increase energy efficiency and reduce emissions, and medical applications promise to improve our lives and the environment only if difficult science questions are solved. This talk will take a brief look back at the role of low temperature plasma science in enabling entirely new markets and then survey the next generation of emerging plasma applications. The emphasis will be on describing the key science questions and the opportunities for scientific cross cutting collaborations that underscore the need for increased outreach on the part of the plasma science community to improve visibility at the federal program level. This work is supported by the DOE, Office of Science for Fusion Energy Sciences, and Sandia National Laboratories, a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000

Scientist in the Classroom: Highlights of a Plasma Outreach Program

NASA Astrophysics Data System (ADS)

Nagy, A.; Lee, R. L.

2000-10-01

The General Atomics education program ``Scientist in the Classroom'' now in its third year, uses scientists and engineers to present ``Plasma the fourth state of matter,'' to students in the classroom. A program goal is to make science an enjoyable experience while showing students how plasma plays an important role in their world. A fusion overview is presented, including topics on energy and environment. Using hands-on equipment, students manipulate a plasma discharge using magnets, observe its spectral properties and observe the plasma in a fluorescent tube. In addition, they observe physical properties of liquid nitrogen, and use an infrared camera to observe radiant heat energy. Several program benefits are; it costs less than facility tours, is more flexible in scheduling, and is adaptable for grades 2--adult. The program has doubled in coverage since last year, with over 2200 students at 20 schools visited by 8 scientists. Increased participation by the DIII-D staff in this program has been achieved by enlisting them to bring the program to their children's school.

Building an infrastructure at PICKSC for the educational use of kinetic software tools

NASA Astrophysics Data System (ADS)

Mori, W. B.; Decyk, V. K.; Tableman, A.; Fonseca, R. A.; Tsung, F. S.; Hu, Q.; Winjum, B. J.; Amorim, L. D.; An, W.; Dalichaouch, T. N.; Davidson, A.; Joglekar, A.; Li, F.; May, J.; Touati, M.; Xu, X. L.; Yu, P.

2016-10-01

One aim of the Particle-In-Cell and Kinetic Simulation Center (PICKSC) at UCLA is to coordinate a community development of educational software for undergraduate and graduate courses in plasma physics and computer science. The rich array of physical behaviors exhibited by plasmas can be difficult to grasp by students. If they are given the ability to quickly and easily explore plasma physics through kinetic simulations, and to make illustrative visualizations of plasma waves, particle motion in electromagnetic fields, instabilities, or other phenomena, then they can be equipped with first-hand experiences that inform and contextualize conventional texts and lectures. We are developing an infrastructure for any interested persons to take our kinetic codes, run them without any prerequisite knowledge, and explore desired scenarios. Furthermore, we are actively interested in any ideas or input from other plasma physicists. This poster aims to illustrate what we have developed and gather a community of interested users and developers. Supported by NSF under Grant ACI-1339893.

Turbulence experiments on the PKU Plasma Test (PPT) device

NASA Astrophysics Data System (ADS)

Xu, Tianchao; Xiao, Chijie; Yang, Xiaoyi; Chen, Yihang; Yu, Yi; Xu, Min; Wang, Long; Lin, Chen; Wang, Xiaogang

2017-10-01

The PKU Plasma Test (PPT) device is a linear plasma device in Peking University, China. It has a vacuum chamber with 1000mm length and 500mm diameter. A pair of Helmholtz coils can generate toroidal magnetic field up to 2000 Gauss, and plasma was generated by a helicon source. Probes and fast camera were used to diagnose the parameters and got the turbulence spectrums, coherent structure, etc. The dynamics of turbulence, coherent structure and parameter profiles have been analyzed, and it has been found that the turbulence states are related to the equilibrium profiles; Some coherent structures exist and show strongly interactions with the background turbulences; The spatial and temporal evolutions of these coherent structures are related to the amplitude of the density gradient and electric field. These results will help on further studies of plasma transport. This work was supported by the National Natural Science Foundation of China under 11575014 and 11375053, CHINA MOST under 2012YQ030142 and ITER-CHINA program 2015GB120001.

“The Marshall Rosenbluth International Summer School – 2007: Plasma Thermonuclear Fusion and Plasma Astrophysics – 2007”

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stefan, Vladislav Alexander

Contents: H. Berk: Frequency Sweeping Due to Phase Space Structure Formation in Plasmas M. Campbell : The Legacy of Marshall Rosenbluth in the Development of the Laser Fusion Program in the United States J. Candy: Gyrokinetic Simulations of Fusion Plasmas P. Diamond: The Legacy of Marshall Rosenbluth in Magnetic Confinement Theory G-Y. Fu: Nonlinear Hybrid Simulations of Multiple Energetic Particle Driven Alfven Modes in Toroidal Plasmas O. Gurcan: Theory of Intrinsic Rotation and Momentum Transport V. L. Jacobs: Kinetic and Spectral Descriptions for Atomic Processes in Astrophysical and Laboratory Plasmas C. F. Kennel: Marshall Rosenbluth and Roald Sagdeev in Trieste:Themore » Birth of Modern Space Plasma N. A. Krall: The Contribution of Marshall Rosenbluth in the Development of Plasma Drift Wave and Universal Instability Theories C. S. Liu: The Legacy of Marshall Rosenbluth in Laser-Plasma Interaction Research N. Rostoker: Plasma Physics Research With Marshall Rosenbluth - My Teacher R. Z. Sagdeev: The Legacy of Marshall Rosenbluth in Plasma Physics V. Alexander Stefan A Note on the Rosenbluth Paper: Phys. Rev. Letters, 29, 565 (1972), and the Research in Parametric Plasma Theory Thereupon J. W. Van Dam: The Role of Marshall Rosenbluth in the Development of the Thermonuclear Fusion Program in the U.S.A. E. P. Velikhov: Problems in Plasma Astrophysics R. White: The Role of Marshall Rosenbluth in the Development of the Particle and MHD Interaction in Plasmas X. Xu: Edge Gyrokinetic Theory and Continuum Simulations Marshall Nicholas ROSENBLUTH (A Brief Biography) b. February 5,1927 - Albany, New York. d. September 28, 2003 - San Diego, California. M. N. Rosenbluth, a world-acclaimed scientist, is one of the ultimate authorities in plasma and thermonuclear fusion research, often indicated by the sobriquet the "Pope of Plasma Physics." His theoretical contributions have been central to the development of controlled thermonuclear fusion. In the 1950s his pioneering work in plasma instabilities, together with pioneering works of A. Sakharov, I. Tamm, L. Spitzer, Jr., L. A. Artsimovich, and others, led to the design of the TOKAMAK, the principal configuration used for contemporary magnetic fusion experiments. In addition to his research achievements, he has made significant administrative contributions as a scientific advisor in the fields of energy policy and national defense. He is the founder and the first director of The Institute for Fusion Studies at Austin, Texas. M. N. Rosenbluth has been the recipient of the E. O. Lawrence Memorial Award (1964),the Albert Einstein Award (1967),the James Clerk Maxwell prize in Plasma Physics(1976),and the Enrico Fermi Award (1986). M. N. Rosenbluth had been Science Advisor for the INSTITUTE for ADVANCED PHYSICS STUDIES (presently a division of The Stefan University) since 1989. He is the editor-in-chief of the FSRC, (Frontier Science Research Conferences) Book: "NEW IDEAS in TOKAMAK CONFINEMENT" Published by the American Institute of Physics (August 1994) in the Research Trends in Physics Series founded and edited by V. Alexander Stefan in 1989. M. N. Rosenbluth was a member of the American Academy of Arts and Sciences and the National Academy of Sciences of the USA, a Professor Emeritus at the University of California, San Diego, and a Senior Scientist at General Atomics, San Diego.« less

Particle-in-cell simulations of Magnetic Field Generation, Evolution, and Reconnection in Laser-driven Plasmas

NASA Astrophysics Data System (ADS)

Matteucci, Jack; Moissard, Clément; Fox, Will; Bhattacharjee, Amitava

2016-10-01

The advent of high-energy-density physics facilities has introduced the opportunity to experimentally investigate magnetic field dynamics relevant to both ICF and astrophysical plasmas. Recent experiments have demonstrated magnetic reconnection between colliding plasma plumes, where the reconnecting magnetic fields were self-generated in the plasma by the Biermann battery effect. In this study, we simulate these experiments from first principles using 2-D and 3-D particle-in-cell simulations. Simulations self-consistently demonstrate magnetic field generation by the Biermann battery effect, followed by advection by the Hall effect and ion flow. In 2-D simulations, we find in both the collisionless case and the semi-collisional case, defined by eVi × B >> Rei /ne (where Rei is the electron ion momentum transfer) that quantitative agreement with the generalized Ohm's law is only obtained with the inclusion of the pressure tensor. Finally, we document that significant field is destroyed at the reconnection site by the Biermann term, an inverse, `anti-Biermann' effect, which has not been considered previously in analysis of the experiment. The role of the anti-Biermann effect will be compared to standard reconnection mechanisms in 3-D reconnection simulations. This research used resources of the ORLC Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. DoE under Contract No. DE-AC05-00OR22725.

Science objectives of the magnetic field experiment onboard Aditya-L1 spacecraft

NASA Astrophysics Data System (ADS)

Yadav, Vipin K.; Srivastava, Nandita; Ghosh, S. S.; Srikar, P. T.; Subhalakshmi, Krishnamoorthy

2018-01-01

The Aditya-L1 is first Indian solar mission scheduled to be placed in a halo orbit around the first Lagrangian point (L1) of Sun-Earth system in the year 2018-19. The approved scientific payloads onboard Aditya-L1 spacecraft includes a Fluxgate Digital Magnetometer (FGM) to measure the local magnetic field which is necessary to supplement the outcome of other scientific experiments onboard. The in-situ vector magnetic field data at L1 is essential for better understanding of the data provided by the particle and plasma analysis experiments, onboard Aditya-L1 mission. Also, the dynamics of Coronal Mass Ejections (CMEs) can be better understood with the help of in-situ magnetic field data at the L1 point region. This data will also serve as crucial input for the short lead-time space weather forecasting models. The proposed FGM is a dual range magnetic sensor on a 6 m long boom mounted on the Sun viewing panel deck and configured to deploy along the negative roll direction of the spacecraft. Two sets of sensors (tri-axial each) are proposed to be mounted, one at the tip of boom (6 m from the spacecraft) and other, midway (3 m from the spacecraft). The main science objective of this experiment is to measure the magnitude and nature of the interplanetary magnetic field (IMF) locally and to study the disturbed magnetic conditions and extreme solar events by detecting the CME from Sun as a transient event. The proposed secondary science objectives are to study the impact of interplanetary structures and shock solar wind interaction on geo-space environment and to detect low frequency plasma waves emanating from the solar corona at L1 point. This will provide a better understanding on how the Sun affects interplanetary space. In this paper, we shall give the main scientific objectives of the magnetic field experiment and brief technical details of the FGM onboard Aditya-1 spacecraft.

Sunsat-2004 satellite and synoptic VLF payload

NASA Astrophysics Data System (ADS)

Milne, Gw; Hughes, A.; Mostert, S.; Steyn, Wh

Sunsat 2004 is a second satellite from the University of Stellenbosch, with intended suns-synchronous launch in late 2005. The first satellite, Sunsat, was launched in February 1999, and was Africa's first satellite The three-axis stabilised bus will normally point its main solar panel at the sun, but will rotate for imaging. The attitude determination and control system will use coarse sun sensors, magnetometers, rate gyros, and a star mapper, and use reaction wheels and torquer rods for actuation. The payloads include a multispectral pushbroom imager with less than 5m GSD, TV cameras, an Amateur Radio communications payload, and science experiments. The main South African science experiment is a VLF receiver. In the magnetosphere VLF waves play an important role in energy exchange processes with energetic particles. The wave-particle interactions can lead to particle precipitation into the atmosphere or introduce additional energy into particle populations in the magnetosphere. The former is important due to its effect on terrestrial communications while the latter is of interest, as it affects the environment in which satellites operate. A full understanding, of the magnetosphere and phenomena such as the aurora, airglow and particle precipitation, depends on comprehensive wave and particle models together with models of the background plasma density The energetic particle populations and background plasma densities have been extensively modelled using data from a large number of satellite, rocket and ground-based experiments but no comprehensive model of the wave environment exist. The proposed synoptic VLF experiment will start to address this need by locating and tracking the morphology of regions in the magnetosphere where waves are generated. The experiment would consist of a nine channel VLF receiver with a loop antenna. The data would be recorded on board and transmitted to ground stations at appropriate times. A number of additional science payloads are also being evaluated for the mission, and will be reported on in the paper.

Effect of hormonal and energy-related factors on plasma adiponectin in transition dairy cows.

PubMed

Krumm, C S; Giesy, S L; Caixeta, L S; Butler, W R; Sauerwein, H; Kim, J W; Boisclair, Y R

2017-11-01

In transition dairy cows, plasma levels of the insulin-sensitizing hormone adiponectin fall to a nadir at parturition and recover in early lactation. The transition period is also characterized by rapid changes in metabolic and hormonal factors implicated in other species as positive regulators of adiponectin production (i.e., negative energy balance, lipid mobilization) and others as negative regulators (i.e., reduced leptin and insulin and increased growth hormone and plasma fatty acids). To assess the role of onset of negative energy balance and lipid mobilization after parturition, dairy cows were either milked thrice daily (lactating) or never milked (nonlactating) for up to 4 wk after parturition. Plasma adiponectin was 21% higher across time in nonlactating than lactating cows. Moreover, nonlactating cows recovered plasma adiponectin at similar rates as lactating cows even though they failed to lose body condition. Next, we assessed the ability of individual hormones to alter plasma adiponectin in transition dairy cows. In the first experiment, dairy cows received a constant 96-h intravenous infusion of either saline or recombinant human leptin starting on d 8 of lactation. In the second experiment, dairy cows were studied in late pregnancy (LP, starting on prepartum d -31) and again in early lactation (EL, starting on d 7 postpartum) during a 66-h period of basal sampling followed by 48 h of hyperinsulinemic-euglycemia. In the third experiment, cows were studied either in LP (starting on d -40 prepartum) or EL (starting on d 7 postpartum) during a 3-h period of basal sampling followed by 5 d of bovine somatotropin treatment. Plasma adiponectin was reduced by an average of 21% in EL relative to LP in these experiments, but neither leptin, insulin, or growth hormone treatment affected adiponectin in LP or EL. Finally, the possibility that plasma fatty acids repress plasma adiponectin was evaluated by intravenous infusion of a lipid emulsion in nonpregnant, nonlactating cows in the absence or presence of glucagon for 16 consecutive hours. The intralipid infusion increased plasma fatty acid concentration from 102 to over 570 µM within 3 h but had no effect on plasma adiponectin irrespective of presence or absence of glucagon. Overall, these data suggest that energy balance around parturition may regulate plasma adiponectin but do not support roles for lipid mobilization or sustained changes in the plasma concentration of leptin, insulin, growth hormone, or fatty acids. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Ion beam generated modes in the lower hybrid frequency range in a laboratory magnetoplasma

NASA Astrophysics Data System (ADS)

Van Compernolle, B.; Tripathi, S.; Gekelman, W. N.; Colestock, P. L.; Pribyl, P.

2012-12-01

The generation of waves by ion ring distributions is of great importance in many instances in space plasmas. They occur naturally in the magnetosphere through the interaction with substorms, or they can be man-made in ionospheric experiments by photo-ionization of neutral atoms injected perpendicular to the earth's magnetic field. The interaction of a fast ion beam with a low β plasma has been studied in the laboratory. Experiments were performed at the LArge Plasma Device (LAPD) at UCLA. The experiments were done in a Helium plasma (n ≃ 1012 \\ cm-3, B0 = 1000 G - 1800 G, fpe}/f{ce ≃ 1 - 5, Te = 0.25\\ eV, vte ≤ vA). The ion beam \\cite{Tripathi_ionbeam} is a Helium beam with energies ranging from 5 keV to 18 keV. The fast ion velocity is on the order of the Alfvén velocity. The beam is injected from the end of the machine, and spirals down the linear device. Waves were observed below fci in the shear Alfvén wave regime, and in a broad spectrum above fci in the lower hybrid frequency range, the focus of this paper. The wave spectra have distinct peaks close to ion cyclotron harmonics, extending out to the 100th harmonic in some cases. The wave generation was studied for various magnetic fields and background plasma densities, as well as for different beam energies and pitch angles. The waves were measured with 3-axis electric and magnetic probes. Detailed measurements of the perpendicular mode structure will be shown. Langmuir probes were used to measure density and temperature evolution due to the beam-plasma interaction. Retarding field energy analyzers captured the ion beam profiles. The work was performed at the LArge Plasma Device at the Basic Plasma Science Facility (BaPSF) at UCLA, funded by DOE/NSF.

PSI-Center Validation Studies

NASA Astrophysics Data System (ADS)

Nelson, B. A.; Akcay, C.; Glasser, A. H.; Hansen, C. J.; Jarboe, T. R.; Marklin, G. J.; Milroy, R. D.; Morgan, K. D.; Norgaard, P. C.; Shumlak, U.; Sutherland, D. A.; Victor, B. S.; Sovinec, C. R.; O'Bryan, J. B.; Held, E. D.; Ji, J.-Y.; Lukin, V. S.

2014-10-01

The Plasma Science and Innovation Center (PSI-Center - http://www.psicenter.org) supports collaborating validation platform experiments with 3D extended MHD simulations using the NIMROD, HiFi, and PSI-TET codes. Collaborators include the Bellan Plasma Group (Caltech), CTH (Auburn U), HBT-EP (Columbia), HIT-SI (U Wash-UW), LTX (PPPL), MAST (Culham), Pegasus (U Wisc-Madison), SSX (Swarthmore College), TCSU (UW), and ZaP/ZaP-HD (UW). The PSI-Center is exploring application of validation metrics between experimental data and simulations results. Biorthogonal decomposition (BOD) is used to compare experiments with simulations. BOD separates data sets into spatial and temporal structures, giving greater weight to dominant structures. Several BOD metrics are being formulated with the goal of quantitive validation. Results from these simulation and validation studies, as well as an overview of the PSI-Center status will be presented.

High Energy Density Plasmas (HEDP) for studies of basic nuclear science relevant to Stellar and Big Bang Nucleosynthesis

NASA Astrophysics Data System (ADS)

Frenje, Johan

2014-06-01

Thermonuclear reaction rates and nuclear processes have been explored traditionally by means of conventional accelerator experiments, which are difficult to execute at conditions relevant to stellar nucleosynthesis. Thus, nuclear reactions at stellar energies are often studied through extrapolations from higher-energy data or in low-background underground experiments. Even when measurements are possible using accelerators at relevant energies, thermonuclear reaction rates in stars are inherently different from those in accelerator experiments. The fusing nuclei are surrounded by bound electrons in accelerator experiments, whereas electrons occupy mainly continuum states in a stellar environment. Nuclear astrophysics research will therefore benefit from an enlarged toolkit for studies of nuclear reactions. In this presentation, we report on the first use of High Energy Density Plasmas for studies of nuclear reactions relevant to basic nuclear science, stellar and Big Bang nucleosynthesis. These experiments were carried out at the OMEGA laser facility at University of Rochester and the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, in which spherical capsules were irradiated with powerful lasers to compress and heat the fuel to high enough temperatures and densities for nuclear reactions to occur. Four experiments will be highlighted in this presentation. In the first experiment, the differential cross section for the elastic neutron-triton (n-T) scattering at 14.1 MeV was measured with significantly higher accuracy than achieved in accelerator experiments. In the second experiment, the T(t,2n)4He reaction, a mirror reaction to the 3He(3He,2p)4He reaction that plays an important role in the proton-proton chain that transforms hydrogen into ordinary 4He in stars like our Sun, was studied at energies in the range 15-40 keV. In the third experiment, the 3He+3He solar fusion reaction was studied directly, and in the fourth experiment, we probed the T+3He reaction, possibly relevant to Big Bang nucleosynthesis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, S. E.; Schaeffer, D. B.; Everson, E. T.

Two-dimensional hybrid simulations of perpendicular collisionless shocks are modeled after potential laboratory conditions that are attainable in the LArge Plasma Device (LAPD) at the University of California, Los Angeles Basic Plasma Science Facility. The kJ class 1053 nm Nd:Glass Raptor laser will be used to ablate carbon targets in the LAPD with on-target energies of 100-500 J. The ablated debris ions will expand into ambient, partially ionized hydrogen or helium. A parameter study is performed via hybrid simulation to determine possible conditions that could lead to shock formation in future LAPD experiments. Simulation results are presented along with a comparisonmore » to an analytical coupling parameter.« less

Development progress of the Materials Analysis and Particle Probe

NASA Astrophysics Data System (ADS)

Lucia, M.; Kaita, R.; Majeski, R.; Bedoya, F.; Allain, J. P.; Boyle, D. P.; Schmitt, J. C.; Onge, D. A. St.

2014-11-01

The Materials Analysis and Particle Probe (MAPP) is a compact in vacuo surface science diagnostic, designed to provide in situ surface characterization of plasma facing components in a tokamak environment. MAPP has been implemented for operation on the Lithium Tokamak Experiment at Princeton Plasma Physics Laboratory (PPPL), where all control and analysis systems are currently under development for full remote operation. Control systems include vacuum management, instrument power, and translational/rotational probe drive. Analysis systems include onboard Langmuir probes and all components required for x-ray photoelectron spectroscopy, low-energy ion scattering spectroscopy, direct recoil spectroscopy, and thermal desorption spectroscopy surface analysis techniques.

Development progress of the Materials Analysis and Particle Probe.

PubMed

Lucia, M; Kaita, R; Majeski, R; Bedoya, F; Allain, J P; Boyle, D P; Schmitt, J C; Onge, D A St

2014-11-01

The Materials Analysis and Particle Probe (MAPP) is a compact in vacuo surface science diagnostic, designed to provide in situ surface characterization of plasma facing components in a tokamak environment. MAPP has been implemented for operation on the Lithium Tokamak Experiment at Princeton Plasma Physics Laboratory (PPPL), where all control and analysis systems are currently under development for full remote operation. Control systems include vacuum management, instrument power, and translational/rotational probe drive. Analysis systems include onboard Langmuir probes and all components required for x-ray photoelectron spectroscopy, low-energy ion scattering spectroscopy, direct recoil spectroscopy, and thermal desorption spectroscopy surface analysis techniques.

FOREWORD: 23rd National Symposium on Plasma Science & Technology (PLASMA-2008)

NASA Astrophysics Data System (ADS)

Das, A. K.

2010-01-01

The Twentieth Century has been a defining period for Plasma Science and Technology. The state of ionized matter, so named by Irving Langmuir in the early part of twentieth century, has now evolved in to a multidisciplinary area with scientists and engineers from various specializations working together to exploit the unique properties of the plasma medium. There have been great improvements in the basic understanding of plasmas as a many body system bound by complex collective Coulomb interactions of charges, atoms, molecules, free radicals and photons. Simultaneously, many advanced plasma based technologies are increasingly being implemented for industrial and societal use. The emergence of the multination collaborative project International Thermonuclear Experimental Reactor (ITER) project has provided the much needed boost to the researchers working on thermonuclear fusion plasmas. In addition, the other plasma applications like MHD converters, hydrogen generation, advanced materials (synthesis, processing and surface modification), environment (waste beneficiation, air and water pollution management), nanotechnology (synthesis, deposition and etching), light production, heating etc are actively being pursued in governmental and industrial sectors. For India, plasma science and technology has traditionally remained an important area of research. It was nearly a century earlier that the Saha ionization relation pioneered the way to interpret experimental data from a vast range of near equilibrium plasmas. Today, Indian research contributions and technology demonstration capabilities encompass thermonuclear fusion devices, nonlinear plasma phenomena, plasma accelerators, beam plasma interactions, dusty and nonneutral plasmas, industrial plasmas and plasma processing of materials, nano synthesis and structuring, astrophysical and space plasmas etc. India's participation in the ITER programme is now reflected in increased interest in the research and development efforts on Tokamak technology and physics of magnetized fusion plasmas. Our industries have already adopted a large number of plasma processes related to manufacturing, lighting and surface engineering. Indian universities and National Institutes have successfully taken up research projects and building of demonstration equipment that are being used in strategic as well as other industrial applications. In addition, and more importantly, plasma science has triggered research and development effort in many related areas like power supplies, specialized instrumentation and controls, magnets, diagnostics and monitoring, lasers, electron beams, vacuum systems, thermal engineering, material science, fluid dynamics, molecular and nano engineering, molecular chemistry etc. In short, plasma science and technology in India has reached a stage of maturity that can be harnessed for industrial and societal use. The expertise and core competence developed over the years need to be sustained through interactions among researchers as well as nurturing of new research efforts. The Annual Plasma Symposiums have eminently worked towards achievement of that purpose. Like all years, Plasma - 2008 is built around the entire national effort in this field with a special focus on 'Plasmas in Nuclear Fuel Cycle (PANFC)'. The program includes several plenary lectures, invited talks and contributed papers. The manuscripts have been peer reviewed and compiled in the form of Conference Proceedings. I am sure that the online proceedings will be useful and serve as a valuable reference material for active researchers in this field. I would like to take this opportunity to gratefully acknowledge the help and guidance of the National Advisory Committee Chaired by Professor P K Kaw, Director, Institute of Plasma Research, Gandhinagar during the organization of this symposium. My sincere thanks to Dr S Banerjee, Director, Bhabha Atomic Research Center, an acknowledged expert in the field of Materials Science and Technology, for delivering the key note address to set the tenor of the symposium. I would also like to thank the Plasma Science Society of India (PSSI) for agreeing to hold this important event at BARC. Thanks are due to Dr L M Gantayet, Director, BTDG, BARC and chairman, Scientific Program Committee and all my colleagues in the Symposium Organizing Committee who have made this symposium possible. Finally, our thanks to all the Funding agencies, Board of Research in Nuclear Science, Department of Science and Technology, The Board of Fusion Research, and all industrial exhibitor and sponsors for their unstinted support and encouragement. Dr A K Das Chairman, Organizing Committee Bhabha Atomic Research Center, Mumbai

Engaging high school students as plasma science outreach ambassadors

NASA Astrophysics Data System (ADS)

Wendt, Amy; Boffard, John

2017-10-01

Exposure to plasma science among future scientists and engineers is haphazard. In the U.S., plasma science is rare (or absent) in mainstream high school and introductory college physics curricula. As a result, talented students may be drawn to other careers simply due to a lack of awareness of the stimulating science and wide array of fulfilling career opportunities involving plasmas. In the interest of enabling informed decisions about career options, we have initiated an outreach collaboration with the Madison West High School Rocket Club. Rocket Club members regularly exhibit their activities at public venues, including large-scale expos that draw large audiences of all ages. Building on their historical emphasis on small scale rockets with chemical motors, we worked with the group to add a new feature to their exhibit that highlights plasma-based spacecraft propulsion for interplanetary probes. This new exhibit includes a model satellite with a working (low power) plasma thruster. The participating high school students led the development process, to be described, and enthusiastically learned to articulate concepts related to plasma thruster operation and to compare the relative advantages of chemical vs. plasma/electrical propulsion systems for different scenarios. Supported by NSF Grant PHY-1617602.

Developing the science and technology for the Material Plasma Exposure eXperiment

DOE PAGES

Rapp, J.; Biewer, T. M.; Bigelow, T. S.; ...

2017-07-27

Linear plasma generators are cost effective facilities to simulate divertor plasma conditions of present and future fusion reactors. They are used to address important R&D gaps in the science of plasma material interactions and towards viable plasma facing components for fusion reactors. Next generation plasma generators have to be able to access the plasma conditions expected on the divertor targets in ITER and future devices. The steady-state linear plasma device MPEX will address this regime with electron temperatures of 1–10 eV and electron densities ofmore » $$10^{21}{\\text{}}\\!-\\!10^{20}$$ $${\\rm m}^{-3}$$. The resulting heat fluxes are about 10 MW $${\\rm m}^{-2}$$ . MPEX is designed to deliver those plasma conditions with a novel Radio Frequency plasma source able to produce high density plasmas and heat electron and ions separately with electron Bernstein wave (EBW) heating and ion cyclotron resonance heating with a total installed power of 800 kW. The linear device Proto-MPEX, forerunner of MPEX consisting of 12 water-cooled copper coils, has been operational since May 2014. Its helicon antenna (100 kW, 13.56 MHz) and EC heating systems (200 kW, 28 GHz) have been commissioned and 14 MW $${\\rm m}^{-2}$$ was delivered on target. Furthermore, electron temperatures of about 20 eV have been achieved in combined helicon and ECH heating schemes at low electron densities. Overdense heating with EBW was achieved at low heating powers. The operational space of the density production by the helicon antenna was pushed up to $$1.1 \\times 10^{20}$$ $${\\rm m}^{-3}$$ at high magnetic fields of 1.0 T at the target. Finally, the experimental results from Proto-MPEX will be used for code validation to enable predictions of the source and heating performance for MPEX. MPEX, in its last phase, will be capable to expose neutron-irradiated samples. In this concept, targets will be irradiated in ORNL's High Flux Isotope Reactor and then subsequently exposed to fusion reactor relevant plasmas in MPEX.« less

Developing the science and technology for the Material Plasma Exposure eXperiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, J.; Biewer, T. M.; Bigelow, T. S.

Linear plasma generators are cost effective facilities to simulate divertor plasma conditions of present and future fusion reactors. They are used to address important R&D gaps in the science of plasma material interactions and towards viable plasma facing components for fusion reactors. Next generation plasma generators have to be able to access the plasma conditions expected on the divertor targets in ITER and future devices. The steady-state linear plasma device MPEX will address this regime with electron temperatures of 1–10 eV and electron densities ofmore » $$10^{21}{\\text{}}\\!-\\!10^{20}$$ $${\\rm m}^{-3}$$. The resulting heat fluxes are about 10 MW $${\\rm m}^{-2}$$ . MPEX is designed to deliver those plasma conditions with a novel Radio Frequency plasma source able to produce high density plasmas and heat electron and ions separately with electron Bernstein wave (EBW) heating and ion cyclotron resonance heating with a total installed power of 800 kW. The linear device Proto-MPEX, forerunner of MPEX consisting of 12 water-cooled copper coils, has been operational since May 2014. Its helicon antenna (100 kW, 13.56 MHz) and EC heating systems (200 kW, 28 GHz) have been commissioned and 14 MW $${\\rm m}^{-2}$$ was delivered on target. Furthermore, electron temperatures of about 20 eV have been achieved in combined helicon and ECH heating schemes at low electron densities. Overdense heating with EBW was achieved at low heating powers. The operational space of the density production by the helicon antenna was pushed up to $$1.1 \\times 10^{20}$$ $${\\rm m}^{-3}$$ at high magnetic fields of 1.0 T at the target. Finally, the experimental results from Proto-MPEX will be used for code validation to enable predictions of the source and heating performance for MPEX. MPEX, in its last phase, will be capable to expose neutron-irradiated samples. In this concept, targets will be irradiated in ORNL's High Flux Isotope Reactor and then subsequently exposed to fusion reactor relevant plasmas in MPEX.« less

Close-out report with links to abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marmar, Earl S.

This grant provided A/V support for two technical meetings of the Edge Coordinating Committee: (1) Nov 13, 2013 (co-located with the APS-DPP meeting in Denver, CO) https://ecc.mit.edu/fall-2013-technical-meeting#overlay-context=ecc-meetings; (2) April 28-May 1, 2015 (embedded sessions in the Transport Task Force Meeting, Salem, MA) http://www-internal.psfc.mit.edu/TTF2015/index.html. The ultimate goal of the U.S. Transport Task Force is to develop a physics-based understanding of particle, momentum and heat transport in magnetic fusion devices. This understanding should be of sufficient depth that it allows the development of predictive models of plasma transport that can be validated against experiment, and then used to anticipate the future performancemore » of burning plasmas in ITER, as well as to provide guidance for the design of next-step fusion nuclear science facilities. To achieve success in transport science, it is essential to characterize local fluctuations and transport in toroidal plasmas, to understand the basic mechanisms responsible for transport, and ultimately to control these transport processes. These goals must be pursued in multiple areas, and these topics evolve in order to reflect current interests.« less

Katherine E. Weimer Award: X-ray light sources from laser-plasma and laser-electron interaction: development and applications

NASA Astrophysics Data System (ADS)

Albert, Felicie

2017-10-01

Bright sources of x-rays, such as synchrotrons and x-ray free electron lasers (XFEL) are transformational tools for many fields of science. They are used for biology, material science, medicine, or industry. Such sources rely on conventional particle accelerators, where electrons are accelerated to gigaelectronvolts (GeV) energies. The accelerated particles are wiggled in magnetic structures to emit x-ray radiation that is commonly used for molecular crystallography, fluorescence studies, chemical analysis, medical imaging, and many other applications. One of the drawbacks of these machines is their size and cost, because electric field gradients are limited to about 100 V/M in conventional accelerators. Particle acceleration in laser-driven plasmas is an alternative to generate x-rays via betatron emission, Compton scattering, or bremsstrahlung. A plasma can sustain electrical fields many orders of magnitude higher than that in conventional radiofrequency accelerator structures. When short, intense laser pulses are focused into a gas, it produces electron plasma waves in which electrons can be trapped and accelerated to GeV energies. X-ray sources, driven by electrons from laser-wakefield acceleration, have unique properties that are analogous to synchrotron radiation, with a 1000-fold shorter pulse. An important use of x-rays from laser plasma accelerators is in High Energy Density (HED) science, which requires laser and XFEL facilities to create in the laboratory extreme conditions of temperatures and pressures that are usually found in the interiors of stars and planets. To diagnose such extreme states of matter, the development of efficient, versatile and fast (sub-picosecond scale) x-ray probes has become essential. In these experiments, x-ray photons can pass through dense material, and absorption of the x-rays can be directly measured, via spectroscopy or imaging, to inform scientists about the temperature and density of the targets being studied. Performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344, supported by the LLNL LDRD program (16ERD024), and by the DOE Office Science Early Career Research Program (SCW1575).

Two-temperature equilibration in warm dense hydrogen measured with x-ray scattering from the LCLS

NASA Astrophysics Data System (ADS)

Fletcher, Luke; High Energy Density Sciences Collaboration

2017-10-01

Understanding the properties of warm dense hydrogen plasmas is critical for modeling stellar and planetary interiors, as well as for inertial confinement fusion (ICF) experiments. Of central importance are the electron-ion collision and equilibration times that determine the microscopic properties in a high energy density state. Spectrally and angularly resolved x-ray scattering measurements from fs-laser heated hydrogen have resolved the picosecond evolution and energy relaxation from a two-temperature plasma towards thermodynamic equilibrium in the warm dense matter regime. The interaction of rapidly heated cryogenic hydrogen irradiated by a 400 nm, 5x1017 W/cm2 , 70 fs-laser is visualized with ultra-bright 5.5 kev x-ray pulses from the Linac Coherent Light (LCLS) source in 1 Hz repetition rate pump-probe setting. We demonstrate that the energy relaxation is faster than many classical binary collision theories that use ad hoc cutoff parameters used in the Landau-Spitzer determination of the Coulomb logarithm. This work was supported by the DOE Office of Science, Fusion Energy Science under contract No. SF00515 and supported under FWP 100182 and DOE Office of Basic Energy Sciences, Materials Sciences and Engineering Division, contract DE-AC02-76SF00515.

New Horizons at Pluto

NASA Technical Reports Server (NTRS)

2007-01-01

Artist's concept of the New Horizons spacecraft as it approaches Pluto and its largest moon, Charon, in July 2015. The craft's miniature cameras, radio science experiment, ultraviolet and infrared spectrometers and space plasma experiments will characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto's atmosphere in detail. The spacecraft's most prominent design feature is a nearly 7-foot (2.1-meter) dish antenna, through which it will communicate with Earth from as far as 4.7 billion miles (7.5 billion kilometers) away.

Final Scientific Report: Experimental Investigation of Reconnection in a Line-tied Plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forest, Cary

This grant used funding from the NSF/DoE Partnership on Plasma Science to investigate magnetic reconnection phenomena in a line-tied pinch experiment. The experiment was upgraded from a previous device intended to study fusion plasma-related instabilities to a new configuration capable of studying a number of new, previously unstudied configurations. A high spatial and time resolution array of magnetic probes was constructed to measure time evolving structures present as instability and turbulence developed. The most important new equilibrium made possible by this grant was a Zero-Net-Current equilibrium that models the footpoint twisting of solar flux tubes that occurs prior to solarmore » eruptions (flares and coronal mass ejections). This new equilibrium was successfully created in the lab, and it exhibited a host of instabilities. In particular, at low current when the equilibrium was not overly stressed, a saturated internal kink mode oscillation was observed. At high current, 2 D magnetic turbulence developed which we attribute to the lack of a equilibrium brought about by a subcritical transition to turbulence. A second set of experiments involved the turbulent interactions of a collection of flux tubes all being twisted independently, a problem known as the Parker Problem. Current profiles consisting of 2, 3 and 4 guns were used to impose a fine scale drive, and resulted in a new experimental platform in which the injection scale of the magnetic turbulence could be controlled. First experiments in this configuration support the conclusion that an inverse cascade of magnetic energy occurred which self-organized the plasma into a nearly axisymmetric current distribution.« less

Bicoherence Analysis of Electrostatic Interchange Mode Coupling in a Turbulent Laboratory Magnetosphere

NASA Astrophysics Data System (ADS)

Abler, M. C.; Saperstein, A.; Yan, J. R.; Mauel, M. E.

2017-10-01

Plasmas confined by a strong dipole field exhibit interchange and entropy mode turbulence, which previous experiments have shown respond locally to active feedback. On the Collisionless Terrella Experiment (CTX), this turbulence is characterized by low frequency, low order, quasi-coherent modes with complex spectral dynamics. We apply bicoherence analysis to study nonlinear phase coupling in a variety of scenarios. First, we study the self-interaction of the naturally occurring interchange turbulence; this analysis is then expanded to include the effects of driven modes in the frequency range of the background turbulent oscillations. Initial measurements of coupling coefficients are presented in both cases. Driven low frequency interchange modes are observed to generate multiple harmonics which persist throughout the plasma, becoming weaker as they propagate away from the actuator in the direction of the electron magnetic drift. Future work is also discussed, including application of wavelet bicoherence analysis, excitation of interchange modes at multiple frequencies, and applications to planetary magnetospheres. Supported by NSF-DOE Partnership for Plasma Science Grants DOE-DE-FG02-00ER54585.

Experiment-Model Comparisons of Turbulence, Transport, and Flows in a Magnetized Linear Plasma Using a Global Two-Fluid Braginskii Solver

NASA Astrophysics Data System (ADS)

Gilmore, M.; Fisher, D. M.; Kelly, R. F.; Hatch, M. W.; Rogers, B. N.

2017-10-01

Ongoing experiments and numerical modeling of the dynamics of electrostatic turbulence and transport in the presence of flow shear are being conducted in helicon plasmas in the linear HelCat (Helicon-Cathode) device. Modeling is being done using GBS, a 3D, global two-fluid Braginskii code that solves self-consistently for plasma equilibrium as well as fluctuations. Past experimental measurements of flows have been difficult to reconcile with simple expectations, such as azimuthal flows being dominated by Er x Bz rotation. Therefore, recent measurements have focused on understanding plasma flows, and the role of neutral dynamics. In the model, a set of two-fluid drift-reduced Braginskii equations are evolved using the Global Braginskii Solver Code (GBS). For low-field helicon-sourced Ar plasmas a non-negligible cross-field thermal collisional term must be added to shift the electric potential in the ion momentum and vorticity equations as the ions are unmagnetized. Significant radially and axially dependent neutral profiles are also included in the simulations to try and match those observed in HelCat. Ongoing simulations show a mode dependence on the axial magnetic field along with strong axial variations that suggest drift waves may be important in the low-field case. Supported by U.S. National Science Foundation Award 1500423.

Global Geospace Science/Polar Plasma Laboratory: POLAR

NASA Technical Reports Server (NTRS)

1996-01-01

The Global Geospace Science (GGS) Project is discussed as part of the International Solar-Terrestrial Physics (ISTP) Science Initiative. The objectives of Polar Plasma Laboratory (POLAR), one of the two spacecraft to be used by the Project to fill critical gaps in the scientific understanding of solar and plasma physics, are outlined. POLAR Laboratory is described, along with POLAR instrumentation, support subsystems, and orbits. Launch vehicle and injection into orbit are also addressed.

Spacelab

NASA Image and Video Library

1983-01-01

This double exposure image shows Spacelab-1 in the cargo bay of orbiter Columbia. From top to bottom inside the cargo bay are the Spacelab Access Turnel, which is connected to the mid-deck of the orbiter; the Spacelab module, a pressurized module in which scientists conduct experiments not possible on Earth; and Spacelab pallets, which can hold instruments for the experiments requiring direct exposure to space. The first Spacelab mission, Spacelab-1, sponsored jointly and shared equally by NASA and the European Space Agency, was a multidisciplinary mission; that is, investigations were performed in several different fields of scientific research. The overall goal of the mission was to verify Spacelab performance through a variety of scientific experiments. The disciplines represented by these experiments were astronomy and solar physics, earth observations, space plasma physics, materials sciences, atmospheric physics, and life sciences. International in nature, Spacelab-1 conducted experiments from the United States, Japan, the Netherlands, United Kingdom, Beluga, France, Germany, Italy, and Switzerland. Spacelab-1 was launched from the Kennedy Space Center on November 28, 1983 aboard the orbiter Columbia (STS-9). The Marshall Space Flight Center was responsible for managing the Spacelab missions.

Plasma Detachment Mechanisms in Propulsive Magnetic Nozzles

DTIC Science & Technology

2013-03-07

distribution is unlimited. 41A. Fruchtman, Phys. Rev. Lett. 96, 065002 (2006). 42M. Merino and E. Ahedo, IEEE Trans. Plasma Sci. 39, 2938 (2011). 43J...Ahedo, E., “Simulation of plasma flows in divergent magnetic nozzles,” IEEE Transactions on Plasma Science, Vol. 39, No. 11, 2011, pp. 2938 –2939...Plasma Science, Vol. 39, No. 11, 2011, pp. 2938 –2939. 14Zucrow, M. and Hoffman, J., Gas dynamics, Wiley, New York, 1976. 15Ahedo, E., “Parametric analysis

Discharge characteristics and hydrodynamics behaviors of atmospheric plasma jets produced in various gas flow patterns

NASA Astrophysics Data System (ADS)

Setsuhara, Yuichi; Uchida, Giichiro; Nakajima, Atsushi; Takenaka, Kosuke; Koga, Kazunori; Shiratani, Masaharu

2015-09-01

Atmospheric nonequilibrium plasma jets have been widely employed in biomedical applications. For biomedical applications, it is an important issue to understand the complicated mechanism of interaction of the plasma jet with liquid. In this study, we present analysis of the discharge characteristics of a plasma jet impinging onto the liquid surface under various gas flow patterns such as laminar and turbulence flows. For this purpose, we analyzed gas flow patters by using a Schlieren gas-flow imaging system in detail The plasma jet impinging into the liquid surface expands along the liquid surface. The diameter of the expanded plasma increases with gas flow rate, which is well explained by an increase in the diameter of the laminar gas-flow channel. When the gas flow rate is further increased, the gas flow mode transits from laminar to turbulence in the gas flow channel, which leads to the shortening of the plasm-jet length. Our experiment demonstrated that the gas flow patterns strongly affect the discharge characteristics in the plasma-jet system. This study was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas ``Plasma Medical Innovation'' (24108003) from the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT).

The Feasibility of Applying AC Driven Low-Temperature Plasma for Multi-Cycle Detonation Initiation

NASA Astrophysics Data System (ADS)

Zheng, Dianfeng

2016-11-01

Ignition is a key system in pulse detonation engines (PDE). As advanced ignition methods, nanosecond pulse discharge low-temperature plasma ignition is used in some combustion systems, and continuous alternating current (AC) driven low-temperature plasma using dielectric barrier discharge (DBD) is used for the combustion assistant. However, continuous AC driven plasmas cannot be used for ignition in pulse detonation engines. In this paper, experimental and numerical studies of pneumatic valve PDE using an AC driven low-temperature plasma igniter were described. The pneumatic valve was jointly designed with the low-temperature plasma igniter, and the numerical simulation of the cold-state flow field in the pneumatic valve showed that a complex flow in the discharge area, along with low speed, was beneficial for successful ignition. In the experiments ethylene was used as the fuel and air as oxidizing agent, ignition by an AC driven low-temperature plasma achieved multi-cycle intermittent detonation combustion on a PDE, the working frequency of the PDE reached 15 Hz and the peak pressure of the detonation wave was approximately 2.0 MPa. The experimental verifications of the feasibility in PDE ignition expanded the application field of AC driven low-temperature plasma. supported by National Natural Science Foundation of China (No. 51176001)

Laser acceleration

NASA Astrophysics Data System (ADS)

Tajima, T.; Nakajima, K.; Mourou, G.

2017-02-01

The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

The U.S. Rosetta Project at Its First Science Target: Asteroid (2867) Steins, 2008

NASA Technical Reports Server (NTRS)

Alexander, C.; Sweetnam, D.; Gulkis, S.; Weissman, P.; Holmes, D.; Parker, J.; Burch, J.; Goldstein, R.; Mokashi, P.; Fuselier, S.;

Analysis of pre-flight modulator voltage calibration data for the Voyager plasma science experiment

NASA Technical Reports Server (NTRS)

Nastov, Ognen

1988-01-01

The Voyager Plasma Science (PLS) modulator calibration (MVM) data analysis was undertaken in order to check the correctness of the fast A/D converter formulas that connect low voltage monitor signals (MV) with digital outputs (DN), to determine the proportionality constants between the actual modulator grid potential (V) and the monitor voltage (MV), and to establish an algorithm to link the digitized readouts (DN) with the actual grid potential (V). The analysis results are surprising in that the derived conversion constants deviate by fairly significant amounts from their nominal values. However, it must be kept in mind that the test results which were used for analysis may be very imprecise. Even if it is assumed that the test result errors are very large, they do no appear to be capable to account for all discrepancies between the theoretical expectations and the results of the analysis. Measurements with the flight spare instrument appear to be the only means of investigating these effects further.

Formation and dissociation of dust molecules in dusty plasma

NASA Astrophysics Data System (ADS)

Yan, Jia; Feng, Fan; Liu, Fucheng; Dong, Lifang; He, Yafeng

2016-09-01

Dust molecules are observed in a dusty plasma experiment. By using measurements with high spatial resolution, the formation and dissociation of the dust molecules are studied. The ion cloud in the wake of an upper dust grain attracts the lower dust grain nearby. When the interparticle distance between the upper dust grain and the lower one is less than a critical value, the two dust grains would form a dust molecule. The upper dust grain always leads the lower one as they travel. When the interparticle distance between them is larger than the critical value, the dust molecule would dissociate. Project supported by the National Natural Science Foundation of China (Grant Nos. 11205044 and 11405042), the Natural Science Foundation of Hebei Province, China (Grant Nos. A2011201006 and A2012201015), the Research Foundation of Education Bureau of Hebei Province, China (Grant No. Y2012009), the Program for Young Principal Investigators of Hebei Province, China, and the Midwest Universities Comprehensive Strength Promotion Project, China.

In situ measurements of the plasma bulk velocity near the Io flux tube

NASA Technical Reports Server (NTRS)

Barnett, A.

1985-01-01

The flow around the Io flux tube was studied by analyzing the eleven spectra taken by the Voyager 1 Plasma Science (PLS) experiment in its vicinity. The bulk plasma parameters were determined using a procedure that uses the full response function of the instrument and the data in all four PLS sensors. The mass density of the plasma in the vicinity of Io is found to be 22,500 + or - 2,500 amu/cu cm and its electron density is found to be 1500 + or - 200/cu cm. The Alfven speed was determined using three independent methods; the values obtained are consistent and taken together yield V sub A = 300 + or - 50 km/sec, corresponding to an Alfven Mach number of 0.19 + or - 0.02. For the flow pattern, good agreement was found with the model of Neubauer (1980), and it was concluded that the plasma flows around the flux tube with a pattern similar to the flow of an incompressible fluid around a long cylinder obstacle of radius 1.26 + or - 0.1 R sub Io.

Generating Long Scale-Length Plasma Jets Embedded in a Uniform, Multi-Tesla Magnetic-Field

NASA Astrophysics Data System (ADS)

Manuel, Mario; Kuranz, Carolyn; Rasmus, Alex; Klein, Sallee; Fein, Jeff; Belancourt, Patrick; Drake, R. P.; Pollock, Brad; Hazi, Andrew; Park, Jaebum; Williams, Jackson; Chen, Hui

2013-10-01

Collimated plasma jets emerge in many classes of astrophysical objects and are of great interest to explore in the laboratory. In many cases, these astrophysical jets exist within a background magnetic field where the magnetic pressure approaches the plasma pressure. Recent experiments performed at the Jupiter Laser Facility utilized a custom-designed solenoid to generate the multi-tesla fields necessary to achieve proper magnetization of the plasma. Time-gated interferometry, Schlieren imaging, and proton radiography were used to characterize jet evolution and collimation under varying degrees of magnetization. Experimental results will be presented and discussed. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-NA0001840, by the National Laser User Facility Program, grant number DE-NA0000850, by the Predictive Sciences Academic Alliances Program in NNSA-ASC, grant number DEFC52-08NA28616, and by NASA through Einstein Postdoctoral Fellowship grant number PF3-140111 awarded by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060.

DC response of dust to low frequency AC signals

NASA Astrophysics Data System (ADS)

McKinlay, Michael; Konopka, Uwe; Thomas, Edward

2017-10-01

Macroscopic changes in the shape and equilibrium position of clouds of charged microparticles suspended in a plasma have been observed in response to low frequency AC signals. In these experiments, dusty plasmas consisting of 2-micron diameter silica microspheres suspended between an anode and cathode in an argon, DC glow discharge plasma are produced in a grounded, 6-way cross vacuum chamber. An AC signal, produced by a function generator and amplified by a bipolar op-amp, is superimposed onto the potential from the cathode. The frequencies of the applied AC signals, ranging from tens to hundreds of kHz, are comparable to the ion-neutral collision frequency; well below the ion/electron plasma frequencies, but also considerably higher than the dust plasma frequency. This presentation will detail the experimental setup, present documentation and categorization of observations of the dust response, and present an initial model of the response. This work is supported by funding from the US Dept. of Energy, Grant Number DE-SC0016330, and by the National Science Foundation, Grant Number PHY-1613087.

Surface morphology changes to tungsten under exposure to He ions from an electron cyclotron resonance plasma source

NASA Astrophysics Data System (ADS)

Donovan, David; Buchenauer, Dean; Whaley, Josh; Friddle, Raymond; Wright, Graham

2014-10-01

Exposure of tungsten to low energy (<100 eV) helium plasmas at temperatures between 900-1900 K in both laboratory experiments and tokamaks has been shown to cause severe nanoscale modification of the near surface resulting the growth of tungsten tendrils. We are exploring the potential for using a compact ECR plasma in situ with scanning tunneling microscopy (STM) to investigate the early stages of helium induced tungsten migration. Here we report on characterization of the plasma source for helium plasmas with a desired ion flux of ~1 × 1019 ions m-2 s-1 and the surface morphology changes seen on the exposed tungsten surfaces. Exposures of polished tungsten discs have been performed and characterized using SEM, AFM, and FIB cross section imaging. Bubbles have been seen on the exposed tungsten surface and in sub-surface cross sections growing to up to 150 nm in diameter. Comparisons are made between exposures of warm rolled Plansee tungsten discs and ALMT ITER grade tungsten samples. Work supported by US DOE Contract DE-AC04-94AL85000 and the PSI Science Center.

Establishment and Assessment of Plasma Disruption and Warning Databases from EAST

NASA Astrophysics Data System (ADS)

Wang, Bo; Robert, Granetz; Xiao, Bingjia; Li, Jiangang; Yang, Fei; Li, Junjun; Chen, Dalong

2016-12-01

Disruption database and disruption warning database of the EAST tokamak had been established by a disruption research group. The disruption database, based on Structured Query Language (SQL), comprises 41 disruption parameters, which include current quench characteristics, EFIT equilibrium characteristics, kinetic parameters, halo currents, and vertical motion. Presently most disruption databases are based on plasma experiments of non-superconducting tokamak devices. The purposes of the EAST database are to find disruption characteristics and disruption statistics to the fully superconducting tokamak EAST, to elucidate the physics underlying tokamak disruptions, to explore the influence of disruption on superconducting magnets and to extrapolate toward future burning plasma devices. In order to quantitatively assess the usefulness of various plasma parameters for predicting disruptions, a similar SQL database to Alcator C-Mod for EAST has been created by compiling values for a number of proposed disruption-relevant parameters sampled from all plasma discharges in the 2015 campaign. The detailed statistic results and analysis of two databases on the EAST tokamak are presented. supported by the National Magnetic Confinement Fusion Science Program of China (No. 2014GB103000)

Laboratory studies of stagnating plasma flows with applications to inner solar system and stellar bow shocks

NASA Astrophysics Data System (ADS)

Weber, T. E.; Smith, R. J.; Hsu, S. C.

2016-10-01

Supercritical magnetized collisionless shocks are thought to play a dominant role in the overall partition of energy throughout the universe by converting flow kinetic energy to other forms such as thermal and supra-thermal populations, magnetic field enhancement, turbulence, and energetic particles. The Magnetized Shock Experiment (MSX) at LANL creates conditions similar to those of inner solar system and stellar bow shocks by accelerating hot (100s of eV during translation) dense (1022 - 1023 m-3) Field Reversed Configuration (FRC) plasmoids to 100s of km/s; resulting in β 1, collisionless plasma flows with Msonic and MAlfvén 10. The drifting FRC can be made to impinge upon a variety of static obstacles including: a strong mirror or cusp magnetic field (mimicking magnetically excited shocks such as the Earth's bow shock), plasma pileup from a solid obstacle (similar to the bow shocks of Mercury and the Moon), and a neural gas puff (bow shocks of Venus or the comets). Characteristic shock length and time scales that are both large enough to observe yet small enough to fit within the experiment, enabling study of the complex interplay of kinetic and fluid processes that mediate cosmic shocks and can generate non-thermal distributions, produce density and magnetic field enhancements much greater than predicted by fluid theory, and accelerate particles. An overview of the experimental program will be presented, including recent results. This work is supported by the U.S. DOE, Office of Science, Office of Fusion Energy Sciences under Contract No. DE-AC52-06NA25369.

Magnetic flux pile-up and ion heating in a current sheet formed by colliding magnetized plasma flows

NASA Astrophysics Data System (ADS)

Suttle, L.; Hare, J.; Lebedev, S.; Ciardi, A.; Loureiro, N.; Niasse, N.; Burdiak, G.; Clayson, T.; Lane, T.; Robinson, T.; Smith, R.; Stuart, N.; Suzuki-Vidal, F.

2017-10-01

We present data from experiments carried out at the Magpie pulsed power facility, which show the detailed structure of the interaction of counter-streaming magnetized plasma flows. In our quasi-2D setup, continuous supersonic flows are produced with strong embedded magnetic fields of opposing directions. Their interaction leads to the formation of a dense and long-lasting current sheet, where we observe the pile-up of the magnetic flux at the sheet boundary, as well as the annihilation of field inside, accompanied by an increase in plasma temperature. Spatially resolved measurements with Faraday rotation polarimetry, B-dot probes, XUV imaging, Thomson scattering and laser interferometry diagnostics show the detailed distribution of the magnetic field and other plasma parameters throughout the system. This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EP/G001324/1, and by the U.S. Department of Energy (DOE) Awards No. DE-F03-02NA00057 and No. DE-SC-0001063.

Plasma Acceleration by Rotating Magnetic Field Method using Helicon Source

NASA Astrophysics Data System (ADS)

Furukawa, Takeru; Shimura, Kaichi; Kuwahara, Daisuke; Shinohara, Shunjiro

2017-10-01

Electrodeless plasma thrusters are very promising due to no electrode damage, leading to realize further deep space exploration. As one of the important proposals, we have been concentrating on Rotating Magnetic Field (RMF) acceleration method. High-dense plasma (up to 1013 cm-3) can be generated by using a radio frequency (rf) external antenna, and also accelerated by an antenna wound around outside of a discharge tube. In this scheme, thrust increment is achieved by the axial Lorentz force caused by non linear effects. RMF penetration condition into plasma can be more satisfied than our previous experiment, by increasing RMF coil current and decreasing the RMF frequency, causing higher thrust and fuel efficiency. Measurements of AC RMF component s have been conducted to investigate the acceleration mechanism and the field penetration experimentally. This study has been partially supported by Grant-in-Aid for Scientific Research (B: 17H02995) from the Japan Society for the Promotion of Science.

The role of platelet rich plasma in musculoskeletal science

PubMed Central

Ahmad, Zafar; Howard, Daniel; Brooks, Roger A; Wardale, John; Henson, Fran MD; Getgood, Alan; Rushton, Neil

2012-01-01

The idea of using platelet rich plasma (PRP) in medicine has been around since the 1970s. It is only more recently that its use has been employed in the area of musculoskeletal science. Platelet rich plasma in this area has received much media attention being used by many celebrity sports athletes for musculoskeletal injuries. Therefore it is important for the musculoskeletal practitioner to be aware of the concepts surrounding its use and application. In this article we cover what platelet rich plasma is, how it is prepared and administered, its potential clinical application, and what the current literature discusses in the various areas of musculoskeletal science. PMID:22768374

Federal Plan for High-End Computing. Report of the High-End Computing Revitalization Task Force (HECRTF)

DTIC Science & Technology

2004-07-01

steadily for the past fifteen years, while memory latency and bandwidth have improved much more slowly. For example, Intel processor clock rates38 have... processor and memory performance) all greatly restrict the ability to achieve high levels of performance for science, engineering, and national...sub-nuclear distances. Guide experiments to identify transition from quantum chromodynamics to quark -gluon plasma. Accelerator Physics Accurate

Dusty (complex) plasmas: recent developments, advances, and unsolved problems

NASA Astrophysics Data System (ADS)

Popel, Sergey

The area of dusty (complex) plasma research is a vibrant subfield of plasma physics that be-longs to frontier research in physical sciences. This area is intrinsically interdisciplinary and encompasses astrophysics, planetary science, atmospheric science, magnetic fusion energy sci-ence, and various applied technologies. The research in dusty plasma started after two major discoveries in very different areas: (1) the discovery by the Voyager 2 spacecraft in 1980 of the radial spokes in Saturn's B ring, and (2) the discovery of the early 80's growth of contaminating dust particles in plasma processing. Dusty plasmas are ubiquitous in the universe; examples are proto-planetary and solar nebulae, molecular clouds, supernovae explosions, interplanetary medium, circumsolar rings, and asteroids. Within the solar system, we have planetary rings (e.g., Saturn and Jupiter), Martian atmosphere, cometary tails and comae, dust clouds on the Moon, etc. Close to the Earth, there are noctilucent clouds and polar mesospheric summer echoes, which are clouds of tiny (charged) ice particles that are formed in the summer polar mesosphere at the altitudes of about 82-95 km. Dust and dusty plasmas are also found in the vicinity of artificial satellites and space stations. Dust also turns out to be common in labo-ratory plasmas, such as in the processing of semiconductors and in tokamaks. In processing plasmas, dust particles are actually grown in the discharge from the reactive gases used to form the plasmas. An example of the relevance of industrial dusty plasmas is the growth of silicon microcrystals for improved solar cells in the future. In fact, nanostructured polymorphous sili-con films provide solar cells with high and time stable efficiency. These nano-materials can also be used for the fabrication of ultra-large-scale integration circuits, display devices, single elec-tron devices, light emitting diodes, laser diodes, and others. In microelectronic industries, dust has to be kept under control in the manufacture of microchips, otherwise charged dust particles (also known as killer particles) can destroy electronic circuits. In magnetic fusion research using tokamaks, one realizes that the absorption of tritium by dust fragments could cause a serious health hazard. The evaporation of dust particles could also lead to bremsstrahlung adversely affecting the energy gain of the tokamaks or other fusion devices. The specific features of dusty plasmas are a possibility of the formation of dust Coulomb lattices and the anomalous dissi-pation arising due to the interplay between plasmas and charged dust grains. These features determine new physics of dusty plasmas including, in particular, phase transitions and critical point phenomena, wave propagation, nonlinear effects and turbulence, dissipative and coherent structures, etc. The present review covers the main aspects of the area of dusty (complex) plasma research. The author acknowledges the financial support of the Division of Earth Sci-ences, Russian Academy of Sciences (the basic research program "Nanoscale particles in nature and technogenic products: conditions of existence, physical and chemical properties, and mech-anisms of formation"'), of the Division of Physical Sciences, Russian Academy of Sciences (the basic research program "Plasma physics in the Solar system"), of the Dynasty Foundation, as well as of the Russian Foundation for Basic Research.

INTRODUCTION: Award of the 2003 Hannes Alfvén Prize of the European Physical Society to Professor Vladimir Evgenievitch Fortov

NASA Astrophysics Data System (ADS)

Wagner, F.

2003-12-01

The Hannes Alfvén Prize of the European Physical Society for Outstanding Contributions to Plasma Physics (2003) has been awarded to Vladimir Evgenievitch Fortov `for his seminal contributions in the area of non-ideal plasmas and strongly coupled Coulomb systems, and for his pioneering work on the generation and investigation of plasmas under extreme conditions'. Vladimir Evgenievitch Fortov was born on 23 January 1946 in Noginsk, Russia. He studied physics at the Moscow Institute of Physics and Technology (PhD in 1976). In 1978 he was made a Professor and in 1991 he was awarded the Chair of the Moscow Institute of Physics and Technology. In the same year he became a Member of the Russian Academy of Sciences and was its vice-chairman from 1996 to 2001. From 1996 to 1998, Professor Fortov went into politics where he was just as successful, becoming Deputy Prime Minister of the Government of the Russian Federation and Minister of Science and Technology of the Russian Federation. Professor Fortov has made outstanding experimental and theoretical contributions to low temperature plasma physics. His pioneering work investigating non-ideal plasmas produced by intense shock waves initiated a new research field---the physical properties of highly compressed plasmas with strong inter-particle interactions. Under the leadership of Professor Fortov, experimental methods for generating and diagnosing these plasmas under extreme conditions were developed. To generate intense shock waves, a broad spectrum of drivers was used---chemical explosives, hypervelocity impact, lasers, relativistic electrons, heavy-ion and soft x-ray beams. Measurements of the equation of state, transport and optical properties of strongly coupled plasmas were carried out, including the interesting region lying between condensed matter and rarefied plasmas where specific plasma phase transitions and insulator--metal transitions were expected and explored. In another area of strongly coupled plasmas, Professor Fortov led theoretical and experimental studies on `dusty plasmas', carried out over a wide range of plasma parameters, using a broad spectrum of experimental techniques and devices. These studies embraced thermal combustion, glow and rf discharges and plasmas induced by cosmic ultraviolet and nuclear radiation. Under many of these conditions, ordered structures of dust in plasma liquids and plasma crystals were observed for the first time. Investigations of dusty plasmas induced by solar radiation and dust structures in DC glow discharges were first carried out on the Mir space station under micro-gravity conditions. The Russian--German experiment on dusty plasma crystals in space was successfully started on the International Space Station (ISS) in March 2001. This experiment was the first physics experiment on board the ISS. On the basis of his experimental results, Professor Fortov developed a general method of constructing semi-empirical equations of state of highly compressed materials. He put forward theoretical models of thermodynamical, transport and optical properties of strongly non-ideal plasmas. On the basis of these models Professor Fortov developed two-dimensional and three-dimensional computer codes for computer simulations of the processes in advanced energetic, space, nuclear and aviation systems based on high energy density plasmas. Professor Fortov has not only contributed to plasma theory but also to more applied topics. His laboratory participated in international space projects like the VEGA project (plasma dust impact phenomena), as well as the Halley Comet exploration, and studied plasma and shock wave phenomena stimulated by the impact of the Shoemaker-Levy 9 comet with Jupiter. Professor Fortov is an internationally well known scientist. He collaborates actively with many plasma laboratories and institutions. He has received many national and international awards, including several USSR and Russian State Awards, the A P Karpinskii-Toepfer Scientific Award for Physics and Chemistry (1997), the P Bridgman Award for High Pressure Plasma Investigations and Achievements in High Pressure Physics and Chemistry (1999), the A Einstein Medal of UNESCO (2000) and the Max Planck Award for Physics (2002). It is therefore with great pleasure and honour that the Plasma Physics Division of the European Physical Society has awarded the Hannes Alfvén prize this year to Professor Vladimir Evgenievitch Fortov. This article first appeared on the Europhyisics News website.

Short Intense Ion Pulses for Materials and Warm Dense Matter Research

NASA Astrophysics Data System (ADS)

Seidl, Peter; Ji, Q.; Lidia, S. M.; Persaud, A.; Stettler, M.; Takakuwa, J. H.; Waldron, W. L.; Schenkel, T.; Barnard, J. J.; Friedman, A.; Grote, D. P.; Davidson, R. C.; Gilson, E. P.; Kaganovich, I. D.

2015-11-01

We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r <1 mm within 2 ns FWHM and approximately 1010 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li + ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. We will describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminium perovskite using the fully integrated accelerator and neutralized drift compression components (arXiv:1506.05839). This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

Laboratory Studies of the Nonlinear Interactions of Kink-Unstable Flux Ropes and Shear Alfvén Waves

NASA Astrophysics Data System (ADS)

Vincena, S. T.; Tripathi, S.; Gekelman, W. N.; DeHaas, T.; Pribyl, P.

2017-12-01

Magnetic flux ropes and shear Alfvén waves occur simultaneously in plasmas ranging from solar prominences, to the solar wind, to planetary magnetospheres. If the flux ropes evolve to become unstable to the kink mode, interactions between the kink oscillations and the shear waves can arise, and may even lead to nonlinear phenomena. Experiments aimed at elucidating such interactions are performed in the upgraded Large Plasma Device at UCLA. Flux ropes are generated using a 20 cm x 20 cm LaB6 cathode-anode discharge (with L = 18 m and β ˜ 0.1.) The ropes are embedded in a larger, otherwise current-free, cylindrical (r = 30cm) ambient plasma produced by a second cathode. Shear Alfvén waves are launched using externally fed antennas having three separate polarizations (azimuthal mode numbers.) The counter-propagating, kink-unstable oscillations and driven shear waves are observed to nonlinearly generate sidebands about the higher, shear wave frequency (evident in power spectra) via three-wave coupling. This is demonstrated though bi-coherence calculations and k-matching. With a fixed kink-mode polarization, a total of six daughter wave patterns are presented. Energy flow is shown to proceed from larger to smaller perpendicular wavelengths. Future work will focus on increasing the plasma beta and wave amplitudes in the quest to observe an evolution to a turbulent state. Work is performed at the US Basic Plasma Science Facility, which is supported by the US Department of Energy and the National Science Foundation.

Converging Resonance Cones in the LAPTAG plasma

NASA Astrophysics Data System (ADS)

Katz, Cami; Ha, Chris; Gekelman, Walter; Pribyl, Patrick; Agmon, Nathan; Wise, Joe; Baker, Bob

2013-10-01

The LAPTAG laboratory is a high school outreach effort that has a 1.5m long 50 cm diameter magnetized plasma device. The plasma is produced by an ICP source (1X109 < n < 5X1011 cm-3) and has computer controlled data acquisition. Ring antennas are used to produce converging resonance cones. The experiment was performed in the quiescent plasma afterglow. The electrostatic cones were produced by rf applied to the rings (80 < f < 120 MHz), where fRF < f

EDITORIAL: Interrelationship between plasma phenomena in the laboratory and in space

NASA Astrophysics Data System (ADS)

Koepke, Mark

2008-07-01

The premise of investigating basic plasma phenomena relevant to space is that an alliance exists between both basic plasma physicists, using theory, computer modelling and laboratory experiments, and space science experimenters, using different instruments, either flown on different spacecraft in various orbits or stationed on the ground. The intent of this special issue on interrelated phenomena in laboratory and space plasmas is to promote the interpretation of scientific results in a broader context by sharing data, methods, knowledge, perspectives, and reasoning within this alliance. The desired outcomes are practical theories, predictive models, and credible interpretations based on the findings and expertise available. Laboratory-experiment papers that explicitly address a specific space mission or a specific manifestation of a space-plasma phenomenon, space-observation papers that explicitly address a specific laboratory experiment or a specific laboratory result, and theory or modelling papers that explicitly address a connection between both laboratory and space investigations were encouraged. Attention was given to the utility of the references for readers who seek further background, examples, and details. With the advent of instrumented spacecraft, the observation of waves (fluctuations), wind (flows), and weather (dynamics) in space plasmas was approached within the framework provided by theory with intuition provided by the laboratory experiments. Ideas on parallel electric field, magnetic topology, inhomogeneity, and anisotropy have been refined substantially by laboratory experiments. Satellite and rocket observations, theory and simulations, and laboratory experiments have contributed to the revelation of a complex set of processes affecting the accelerations of electrons and ions in the geospace plasma. The processes range from meso-scale of several thousands of kilometers to micro-scale of a few meters to kilometers. Papers included in this special issue serve to synthesise our current understanding of processes related to the coupling and feedback at disparate scales. Categories of topics included here are (1) ionospheric physics and (2) Alfvén-wave physics, both of which are related to the particle acceleration responsible for auroral displays, (3) whistler-mode triggering mechanism, which is relevant to radiation-belt dynamics, (4) plasmoid encountering a barrier, which has applications throughout the realm of space and astrophysical plasmas, and (5) laboratory investigations of the entire magnetosphere or the plasma surrounding the magnetosphere. The papers are ordered from processes that take place nearest the Earth to processes that take place at increasing distances from Earth. Many advances in understanding space plasma phenomena have been linked to insight derived from theoretical modeling and/or laboratory experiments. Observations from space-borne instruments are typically interpreted using theoretical models developed to predict the properties and dynamics of space and astrophysical plasmas. The usefulness of customized laboratory experiments for providing confirmation of theory by identifying, isolating, and studying physical phenomena efficiently, quickly, and economically has been demonstrated in the past. The benefits of laboratory experiments to investigating space-plasma physics are their reproducibility, controllability, diagnosability, reconfigurability, and affordability compared to a satellite mission or rocket campaign. Certainly, the plasma being investigated in a laboratory device is quite different from that being measured by a spaceborne instrument; nevertheless, laboratory experiments discover unexpected phenomena, benchmark theoretical models, develop physical insight, establish observational signatures, and pioneer diagnostic techniques. Explicit reference to such beneficial laboratory contributions is occasionally left out of the citations in the space-physics literature in favor of theory-paper counterparts and, thus, the scientific support that laboratory results can provide to the development of space-relevant theoretical models is often under-recognized. It is unrealistic to expect the dimensional parameters corresponding to space plasma to be matchable in the laboratory. However, a laboratory experiment is considered well designed if the subset of parameters relevant to a specific process shares the same phenomenological regime as the subset of analogous space parameters, even if less important parameters are mismatched. Regime boundaries are assigned by normalizing a dimensional parameter to an appropriate reference or scale value to make it dimensionless and noting the values at which transitions occur in the physical behavior or approximations. An example of matching regimes for cold-plasma waves is finding a 45° diagonal line on the log--log CMA diagram along which lie both a laboratory-observed wave and a space-observed wave. In such a circumstance, a space plasma and a lab plasma will support the same kind of modes if the dimensionless parameters are scaled properly (Bellan 2006 Fundamentals of Plasma Physics (Cambridge: Cambridge University Press) p 227). The plasma source, configuration geometry, and boundary conditions associated with a specific laboratory experiment are characteristic elements that affect the plasma and plasma processes that are being investigated. Space plasma is not exempt from an analogous set of constraining factors that likewise influence the phenomena that occur. Typically, each morphologically distinct region of space has associated with it plasma that is unique by virtue of the various mechanisms responsible for the plasma's presence there, as if the plasma were produced by a unique source. Boundary effects that typically constrain the possible parameter values to lie within one or more restricted ranges are inescapable in laboratory plasma. The goal of a laboratory experiment is to examine the relevant physics within these ranges and extrapolate the results to space conditions that may or may not be subject to any restrictions on the values of the plasma parameters. The interrelationship between laboratory and space plasma experiments has been cultivated at a low level and the potential scientific benefit in this area has yet to be realized. The few but excellent examples of joint papers, joint experiments, and directly relevant cross-disciplinary citations are a direct result of the emphasis placed on this interrelationship two decades ago. Building on this special issue Plasma Physics and Controlled Fusion plans to create a dedicated webpage to highlight papers directly relevant to this field published either in the recent past or in the future. It is hoped that this resource will appeal to the readership in the laboratory-experiment and space-plasma communities and improve the cross-fertilization between them.

High energy density Z-pinch plasmas using flow stabilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shumlak, U., E-mail: shumlak@uw.edu; Golingo, R. P., E-mail: shumlak@uw.edu; Nelson, B. A., E-mail: shumlak@uw.edu

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. Amore » 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.« less

America COMPETES Act and the FY2010 Budget

DTIC Science & Technology

2009-06-15

Outstanding Junior Investigator, Nuclear Physics Outstanding Junior Investigator, Fusion Energy Sciences Plasma Physics Junior Faculty Development...Spallation Neutron Source Instrumentation Fellowships, and the Fusion Energy Sciences Graduate Fellowships.2 If members of Congress agree with this...Nuclear Physics Outstanding Junior Investigator, Fusion Energy Sciences Plasma Physics Junior Faculty Development; Advanced Scientific Computing

America COMPETES Act and the FY2010 Budget

DTIC Science & Technology

2009-06-29

Outstanding Junior Investigator, Fusion Energy Sciences Plasma Physics Junior Faculty Development; Advanced Scientific Computing Research Early Career...the Fusion Energy Sciences Graduate Fellowships.2 If members of Congress agree with this contention, these America COMPETES Act programs were...Physics Outstanding Junior Investigator, Fusion Energy Sciences Plasma Physics Junior Faculty Development; Advanced Scientific Computing Research Early

The influence of space flight on erythrokinetics in man. Space Life Sciences Missions 1 and 2. Experiment E261

NASA Technical Reports Server (NTRS)

Alfrey, Clarence P.

1995-01-01

The purpose of this contract was to design and conduct experiments that would increase our understanding of the influence of space flight on erythrokinetics and the rapid change that occurs in the red blood cell mass during spaceflight. The experiment designated E261, was flown on Space Life Science missions SLS-1 and SLS-2 (STS 40 and STS 58). Unique features of this experiment included radionuclide tracer studies during flight and frequent in-flight blood samples specifically for the first three or four days of the mission. Plasma volume measurements were made early and late in the missions. Radioactive iron kinetics studies were initiated after one or three days in microgravity since the magnitude of the red blood cell mass decrease dictated that bone marrow production must be decreased very early in the flight. The schedule was designed to study the time course of the changes that occur during spaceflight and to possibly define a mechanism for the rapid reduction in red blood cell mass.

Atmospheric, Magnetospheric, and Plasmas in Space (AMPS) spacelab payload definition study, technical summary document

NASA Technical Reports Server (NTRS)

Keeley, J. T.

1976-01-01

Some 60 instrument candidates and 80 possible science investigations were evaluated. The early analysis emphasized the science aspect in terms of the functional requirements for each of the potential experiments identified by the AMPS science working group. These requirements were then used for the grouping of instruments into practical payloads which would fit the capabilities of the Shuttle/Spacelab. This analysis resulted in the definition of eleven different AMPS configurations. The data were then used to define a typical set of requirements for a flexible AMPS laboratory. The data gathered to this point showed that a planned sequential buildup of the laboratory would be necessary to meet both physical and funding limitations. This led to the definition of five strawman payloads by the science working group, which were used to establish a conceptual laboratory and to define preliminary design of a configuration which could satisfy AMPS needs during the early program period.

Plasma depletions in the Jovian magnetosphere - Evidence of transport and solar wind interaction

NASA Technical Reports Server (NTRS)

Mcnutt, Ralph L., Jr.; Coppi, Paolo S.; Selesnick, Richard S.; Coppi, Bruno

1987-01-01

A series of plasma voids ('dropouts') was observed by the Plasma Science (PLS) experiment in Jupiter's magnetosphere during the Voyager 2 encounter with that planet. A reexamination of Voyager 2 data has led to the conclusion that the dropout phenomenon cannot be a manifestation of a plasma wake produced by Ganymede. Rather, the appearance of the dropouts is attributed to changes in the upstream solar wind conditions and the global state of the magnetosphere; the proximity of Voyager 2 to Ganymede at the time is considered to be coincidental. It is suggested that these dropouts are evidence of a state of 'bubbling' of the magnetosphere that alternates with 'laminar' states in which, as in the case of the Voyager 1 encounter with Jupiter, voids are not present and that these states correspond to different processes by which plasma is transported out of the system. The nature of these states is related to changes in the magnitude of the upstream solar wind ram pressure. In the bubbling state, this pressure is higher than in the laminar state and drives an intermittent instability. The analysis presented is one of the first attempts to introduce, in space physics, recently acquired theoretical notions of the physics of the finite-beta plasmas of which the Jovian magnetospheric plasma is an important example.

Numerical and Experimental Investigation on Electromagnetic Attenuation by Semi-Ellipsoidal Shaped Plasma

NASA Astrophysics Data System (ADS)

He, Xiang; Chen, Jianping; Zhang, Yachun; Chen, Yudong; Zeng, Xiaojun; Tang, Chunmei

2015-10-01

Some reports presented that the radar cross section (RCS) from the radar antenna of military airplanes can be reduced by using a low-temperature plasma screen. This paper gives a numerical and experimental analysis of this RCS-reduction method. The shape of the plasma screen was designed as a semi-ellipsoid in order to make full use of the space in the radar dome. In simulations, we discussed the scattering of the electromagnetic (EM) wave by a perfect electric conductor (PEC) covered with this plasma screen using the finite-difference-time-domain (FDTD) method. The variations of their return loss as a function of wave frequency, plasma density profile, and collision frequency were presented. In the experiments, a semi-ellipsoidal shaped plasma screen was produced. Electromagnetic attenuation of 1.5 GHz EM wave was measured for a radio frequency (RF) power of 5 kW at an argon pressure of 200-1150 Pa. A good agreement is found between simulated and experimental results. It can be confirmed that the plasma screen is useful in applications for stealth of radar antenna. supported by National Natural Science Foundation of China (No. 51107033) and the Fundamental Research Funds for the Central Universities, China (No. 2013B33614)

Diagnosis of a short-pulse dielectric barrier discharge at atmospheric pressure in helium with hydrogen-methane admixtures

NASA Astrophysics Data System (ADS)

Nastuta, A. V.; Pohoata, V.; Mihaila, I.; Topala, I.

2018-04-01

In this study, we present results from electrical, optical, and spectroscopic diagnosis of a short-pulse (250 ns) high-power impulse (up to 11 kW) dielectric barrier discharge at atmospheric pressure running in a helium/helium-hydrogen/helium-hydrogen-methane gas mixture. This plasma source is able to generate up to 20 cm3 of plasma volume, pulsed in kilohertz range. The plasma spatio-temporal dynamics are found to be developed in three distinct phases. All the experimental observations reveal a similar dynamic to medium power microsecond barrier discharges, although the power per pulse and current density are up to two orders of magnitude higher than the case of microsecond barrier discharges. This might open the possibility for new applications in the field of gas or surface processing, and even life science. These devices can be used in laboratory experiments relevant for molecular astrophysics.

Influences of the shielding cylinder on the length of radio-frequency cold atmospheric plasma jets

NASA Astrophysics Data System (ADS)

Li, He-Ping; Li, Jing; Zhang, Xiao-Fei; Guo, Heng; Chen, Jian; Department of Engineering Physics Team

2017-10-01

Cold atmospheric plasma jets driven by a radio frequency power supply contain abundant species and complex chemical reactions, which have wide applications in the fields of materials processing and modifications, food engineering, bio-medical science, etc. Our previous experiments have shown that the total length of a radio-frequency cold atmospheric plasma (RF-CAP) jet can exceed 1 meter with the shielding of a quartz tube. However, the shielding mechanisms of the solid cylinder has not been studied systematically. In this study, a two-dimensional, quasi-steady fluid model is used to investigate the influences of the shielding tube on the length of the RF-CAP jets under different conditions. The simulation results show that the total jet length grows monotonously; while simultaneously, the jet length out of the tube shows a non-monotonic variation trend, with the increase of the tube length, which is in good agreement with the experimental observations. The shielding mechanisms of the solid cylinder on the RF-CAP jet is also discussed in detail based on the modeling results. This work was supported by the National Natural Science Foundation of China (11475103, 21627812), the National Key Research and Development Program of China (2016YFD0102106) and Tsinghua University Initiative Scientific Program (20161080108).

Characteristics of Single Cathode Cascaded Bias Voltage Arc Plasma

NASA Astrophysics Data System (ADS)

Ou, Wei; Deng, Baiquan; Zeng, Xianjun; Gou, Fujun; Xue, Xiaoyan; Zhang, Weiwei; Cao, Xiaogang; Yang, Dangxiao; Cao, Zhi

2016-06-01

A single cathode with a cascaded bias voltage arc plasma source has been developed with a new quartz cathode chamber, instead of the previous copper chambers, to provide better diagnostic observation and access to the plasma optical emission. The cathode chamber cooling scheme is also modified to be naturally cooled only by light emission without cooling water to improve the optical thin performance in the optical path. A single-parameter physical model has been developed to describe the power dissipated in the cascaded bias voltage arc discharge argon plasmas, which have been investigated by utilizing optical emission spectroscopy (OES) and Langmuir probe. In the experiments, discharge currents from 50 A to 100 A, argon flow rates from 800 sccm to 2000 sccm and magnetic fields of 0.1 T and 0.2 T were chosen. The results show: (a) the relationship between the averaged resistivity and the averaged current density exhibits an empirical scaling law as \\barη \\propto \\bar {j}-0.63369 and the power dissipated in the arc has a strong relation with the filling factor; (b) through the quartz, the argon ions optical emission lines have been easily observed and are dominating with wavelengths between 340 nm and 520 nm, which are the emissions of Ar+-434.81 nm and Ar+-442.60 nm line, and the intensities are increasing with the arc current and decreasing with the inlet argon flow rate; and (c) the electron density and temperature can reach 2.0 × 1019 m-3 and 0.48 eV, respectively, under the conditions of an arc current of 90 A and a magnetic field of 0.2 T. The half-width of the ne radial profile is approximatively equal to a few Larmor radii of electrons and can be regarded as the diameter of the plasma jet in the experiments. supported by the International Thermonuclear Experimental Reactor (ITER) Program Special of Ministry of Science and Technology (No. 2013GB114003), and National Natural Science Foundation of China (Nos. 11275135, 11475122)

Strategic Directions in Heliophysics Research Related to Weakly Ionized Plasmas

NASA Technical Reports Server (NTRS)

Spann, James F.

2010-01-01

In 2009, the Heliophysics Division of NASA published its triennial roadmap entitled "Heliophysics; the solar and space physics of a new era." In this document contains a science priority that is recommended that will serve as input into the recently initiated NRC Heliophysics Decadal Survey. The 2009 roadmap includes several science targets recommendations that are directly related to weakly ionized plasmas, including on entitled "Ion-Neutral Coupling in the Atmosphere." This talk will be a brief overview of the roadmap with particular focus on the science targets relevant to weakly ionized plasmas.

Current and Perspective Applications of Dense Plasma Focus Devices

NASA Astrophysics Data System (ADS)

Gribkov, V. A.

2008-04-01

Dense Plasma Focus (DPF) devices' applications, which are intended to support the main-stream large-scale nuclear fusion programs (NFP) from one side (both in fundamental problems of Dense Magnetized Plasma physics and in its engineering issues) as well as elaborated for an immediate use in a number of fields from the other one, are described. In the first direction such problems as self-generated magnetic fields, implosion stability of plasma shells having a high aspect ratio, etc. are important for the Inertial Confinement Fusion (ICF) programs (e.g. as NIF), whereas different problems of current disruption phenomenon, plasma turbulence, mechanisms of generation of fast particles and neutrons in magnetized plasmas are of great interest for the large devices of the Magnetic Plasma Confinement—MPC (e.g. as ITER). In a sphere of the engineering problems of NFP it is shown that in particular the radiation material sciences have DPF as a very efficient tool for radiation tests of prospect materials and for improvement of their characteristics. In the field of broad-band current applications some results obtained in the fields of radiation material sciences, radiobiology, nuclear medicine, express Neutron Activation Analysis (including a single-shot interrogation of hidden illegal objects), dynamic non-destructive quality control, X-Ray microlithography and micromachining, and micro-radiography are presented. As the examples of the potential future applications it is proposed to use DPF as a powerful high-flux neutron source to generate very powerful pulses of neutrons in the nanosecond (ns) range of its duration for innovative experiments in nuclear physics, for the goals of radiation treatment of malignant tumors, for neutron tests of materials of the first wall, blankets and NFP device's constructions (with fluences up to 1 dpa per a year term), and ns pulses of fast electrons, neutrons and hard X-Rays for brachytherapy.

Scattering of magnetic mirror trapped electrons by an Alfven wave

NASA Astrophysics Data System (ADS)

Wang, Y.; Gekelman, W. N.; Pribyl, P.; Papadopoulos, K.; Karavaev, A. V.; Shao, X.; Sharma, A. S.

2010-12-01

Highly energetic particles from large solar flares or other events can be trapped in the Earth’s magnetic mirror field and pose a danger to intricate space satellites. Aiming for artificially de-trapping these particles, an experimental and theoretical study of the interactions of a shear Alfven wave with electrons trapped in a magnetic mirror was performed on the Large Plasma Device (LaPD) at UCLA, with critical parameter ratios matched in the lab plasma to those in space. The experiment was done in a quiescent afterglow plasma with ne≈5×1011cm-3, Te≈0.5eV, B0≈1000G, L=18m, and diameter=60cm. A magnetic mirror was established in LaPD (mirror ratio≈1.5, Lmirror≈3m). An electron population with large v⊥ (E⊥≈1keV) was introduced by microwave heating at upper-hybrid frequency with a 2.45GHz pulsed microwave source at up to 5kW. A shear Alfven wave with arbitrary polarization (fwave≈0.5fci , Bwave/B0≈0.5%) was launched by a Rotating Magnetic Field (RMF) antenna axially 2m away from the center of the mirror. It was observed that the Alfven wave effectively eliminated the trapped electrons. A diagnostic probe was developed for this experiment to measure electrons with large v⊥ in the background plasma. Plasma density and temperature perturbations from the Alfven wave were observed along with electron scattering. Computer simulations tracking single particle motion with wave field are ongoing. In these the Alfven wave’s effect on the electrons pitch angle distribution by a Monte-Carlo method is studied. Planned experiments include upgrading the microwave source for up to 100kW pulses to make electrons with higher transverse energy and longer mirror trapping time. This work is supported by The Office of Naval Research under a MURI award. Work was done at the Basic Plasma Science Facility which is supported by DOE and NSF.

Two LANL laboratory astrophysics experiments

NASA Astrophysics Data System (ADS)

Intrator, Thomas; Weber, Thomas; Feng, Yan; Hutchinson, Trevor; Dunn, John; Akcay, Cihan

2014-06-01

Two laboratory experiments are described that have been built at Los Alamos (LANL) to gain access to a wide range of fundamental plasma physics issues germane to astro, space, and fusion plasmas. The over arching theme is magnetized plasma dynamics which includes significant currents, MHD forces and instabilities, magnetic field creation and annihilation, sheared flows and shocks. The Relaxation Scaling Experiment (RSX) creates current sheets and flux ropes that exhibit fully 3D dynamics, and can kink, bounce, merge and reconnect, shred, and reform in complicated ways. Recent movies from a large data set describe the 3D magnetic structure of a driven and dissipative single flux rope that spontaneously self saturates a kink instability. Examples of a coherent shear flow dynamo driven by colliding flux ropes will also be shown.The Magnetized Shock Experiment (MSX) uses Field reversed configuration (FRC) experimental hardware that forms and ejects FRCs at 150km/sec. This is sufficient to drive a collision less magnetized shock when stagnated into a mirror stopping field region with Alfven Mach number MA=3 so that super critical shocks can be studied. We are building a plasmoid accelerator to drive Mach numbers MA >> 3 to access solar wind and more exotic astrophysical regimes. Unique features of this experiment include access to parallel, oblique and perpendicular shocks, shock region much larger than ion gyro radii and ion inertial length, room for turbulence, and large magnetic and fluid Reynolds numbers.*DOE Office of Fusion Energy Sciences under LANS contract DE-AC52-06NA25396, NASA Geospace NNHIOA044I, Basic, Center for Magnetic Self Organization

Validation of Extended MHD Models using MST RFP Plasmas

NASA Astrophysics Data System (ADS)

Jacobson, C. M.; Chapman, B. E.; Craig, D.; McCollam, K. J.; Sovinec, C. R.

2016-10-01

Significant effort has been devoted to improvement of computational models used in fusion energy sciences. Rigorous validation of these models is necessary in order to increase confidence in their ability to predict the performance of future devices. MST is a well diagnosed reversed-field pinch (RFP) capable of operation over a wide range of parameters. In particular, the Lundquist number S, a key parameter in resistive magnetohydrodynamics (MHD), can be varied over a wide range and provide substantial overlap with MHD RFP simulations. MST RFP plasmas are simulated using both DEBS, a nonlinear single-fluid visco-resistive MHD code, and NIMROD, a nonlinear extended MHD code, with S ranging from 104 to 5 ×104 for single-fluid runs, with the magnetic Prandtl number Pm = 1 . Experiments with plasma current IP ranging from 60 kA to 500 kA result in S from 4 ×104 to 8 ×106 . Validation metric comparisons are presented, focusing on how magnetic fluctuations b scale with S. Single-fluid NIMROD results give S b - 0.21 , and experiments give S b - 0.28 for the dominant m = 1 , n = 6 mode. Preliminary two-fluid NIMROD results are also presented. Work supported by US DOE.

Repetitively Pulsed High Power RF Solid-State System

NASA Astrophysics Data System (ADS)

Bowman, Chris; Ziemba, Timothy; Miller, Kenneth E.; Prager, James; Quinley, Morgan

2017-10-01

Eagle Harbor Technologies, Inc. (EHT) is developing a low-cost, fully solid-state architecture for the generation of the RF frequencies and power levels necessary for plasma heating and diagnostic systems at validation platform experiments within the fusion science community. In Year 1 of this program, EHT has developed a solid-state RF system that combines an inductive adder, nonlinear transmission line (NLTL), and antenna into a single system that can be deployed at fusion science experiments. EHT has designed and optimized a lumped-element NLTL that will be suitable RF generation near the lower-hybrid frequency at the High Beta Tokamak (HBT) located at Columbia University. In Year 2, EHT will test this system at the Helicity Injected Torus at the University of Washington and HBT at Columbia. EHT will present results from Year 1 testing and optimization of the NLTL-based RF system. With support of DOE SBIR.

Short communication: Effect of a citrus extract in lactating dairy cows.

PubMed

Ying, Y; Niu, M; Clarke, A R; Harvatine, K J

2017-07-01

Dry matter intake is a main driver of energy balance in lactating dairy cows, and some plant extracts have been commercially fed to dairy cows to stimulate feed intake. Citrus extracts contain several bioactive components and have been shown to modify metabolism in other animal models. Our hypothesis was that a citrus extract would increase dry matter intake. Two experiments were conducted to determine the effect of a citrus extract on intake and milk production in lactating dairy cows. In experiment one, 11 early-lactation dairy cows (experiment 1; 77 ± 15 d in milk, mean ± standard deviation) were used in a switchback design, and in experiment two, 15 mid-lactation Holstein cows (experiment 2; 157 ± 44 d in milk, mean ± standard deviation) were used in a crossover design. In both experiments, treatments were control (no supplement) or a citrus extract (4 g/d in experiment 1 and 4.5 g/d in experiment 2). Treatment periods were 21 and 14 d in experiment 1 and experiment 2, respectively, with the final 7 d used for sample and data collection. No effect was observed for treatment on dry matter intake, feeding behavior, milk yield, milk fat yield, milk protein yield, or milk composition in either experiment. Treatment also had no effect on milk trans fatty acid profile, but the extract increased total 16 carbon fatty acids 0.9 and 0.6 percentage points in experiment 1 and experiment 2, respectively. Plasma nonesterified fatty acids were decreased 6 h after feeding in both experiments (11.1 and 16.0 μEq/L in experiment 1 and experiment 2, respectively). Plasma insulin was increased 1 h before feeding compared with the control in experiment 1 (3.36 vs. 2.13 µIU/mL) and tended to increase 1.79 units 1 h before feeding in experiment 2. The citrus extract had no effect on feed intake or milk production at the dose investigated, but changed plasma insulin and nonesterified fatty acids, indicating some metabolic effects requiring further investigation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Generation of Shear Alfvén Waves by Repetitive High Power Microwave Pulses Near the Electron Plasma Frequency - A laboratory study of a ``Virtual Antenna''

NASA Astrophysics Data System (ADS)

Wang, Yuhou; Gekelman, Walter; Pribyl, Patrick; van Compernolle, Bart; Papadopoulos, Konstantinos

2015-11-01

ELF / ULF waves are important in terrestrial radio communications but difficult to launch using ground-based structures due to their enormous wavelengths. In spite of this generation of such waves by field-aligned ionospheric heating modulation was first demonstrated using the HAARP facility. In the future heaters near the equator will be constructed and laboratory experiments on cross-field wave propagation could be key to the program's success. Here we report a detailed laboratory study conducted on the Large Plasma Device (LaPD) at UCLA. In this experiment, ten rapid pulses of high power microwaves (250 kW X-band) near the plasma frequency were launched transverse to the background field, and were modulated at a variable fraction (0.1-1.0) of fci. Along with bulk electron heating and density modification, the microwave pulses generated a population of fast electrons. The field-aligned current carried by the fast electrons acted as an antenna that radiated shear Alfvén waves. It was demonstrated that a controllable arbitrary frequency (f

Indirect monitoring shot-to-shot shock waves strength reproducibility during pump-probe experiments

NASA Astrophysics Data System (ADS)

Pikuz, T. A.; Faenov, A. Ya.; Ozaki, N.; Hartley, N. J.; Albertazzi, B.; Matsuoka, T.; Takahashi, K.; Habara, H.; Tange, Y.; Matsuyama, S.; Yamauchi, K.; Ochante, R.; Sueda, K.; Sakata, O.; Sekine, T.; Sato, T.; Umeda, Y.; Inubushi, Y.; Yabuuchi, T.; Togashi, T.; Katayama, T.; Yabashi, M.; Harmand, M.; Morard, G.; Koenig, M.; Zhakhovsky, V.; Inogamov, N.; Safronova, A. S.; Stafford, A.; Skobelev, I. Yu.; Pikuz, S. A.; Okuchi, T.; Seto, Y.; Tanaka, K. A.; Ishikawa, T.; Kodama, R.

2016-07-01

We present an indirect method of estimating the strength of a shock wave, allowing on line monitoring of its reproducibility in each laser shot. This method is based on a shot-to-shot measurement of the X-ray emission from the ablated plasma by a high resolution, spatially resolved focusing spectrometer. An optical pump laser with energy of 1.0 J and pulse duration of ˜660 ps was used to irradiate solid targets or foils with various thicknesses containing Oxygen, Aluminum, Iron, and Tantalum. The high sensitivity and resolving power of the X-ray spectrometer allowed spectra to be obtained on each laser shot and to control fluctuations of the spectral intensity emitted by different plasmas with an accuracy of ˜2%, implying an accuracy in the derived electron plasma temperature of 5%-10% in pump-probe high energy density science experiments. At nano- and sub-nanosecond duration of laser pulse with relatively low laser intensities and ratio Z/A ˜ 0.5, the electron temperature follows Te ˜ Ilas2/3. Thus, measurements of the electron plasma temperature allow indirect estimation of the laser flux on the target and control its shot-to-shot fluctuation. Knowing the laser flux intensity and its fluctuation gives us the possibility of monitoring shot-to-shot reproducibility of shock wave strength generation with high accuracy.

Conference Grant Proposal for ICOPS 2016

DOE Office of Scientific and Technical Information (OSTI.GOV)

Safronova, Alla

ICOPS (International Conference on Plasma Science) is an internationally renowned, well-attended annual conference that involves topics of direct interest to the Office of Fusion Energy Sciences of Department of Energy. In particular, ICOPS 2016 emphasized both the traditional areas of plasma science and the new areas of growth that include but are not limited to Fusion (Inertial, Magnetic and Alternate Concepts), Particle Acceleration with Laser and Beams, High Energy Density Matter, Laser Produced Plasma, Fast Z-pinches, Computational Plasma Physics, Plasma Diagnostics, and such frontiers as studying Warm Dense Matter using the X-ray free electron lasers. The travel support of themore » students at ICOPS comes usually from sponsor organizations. Increasing the participation of outstanding students at ICOPS 2016 who are the first authors of the abstracts and are selected to receive the travel support based on the scientific merit of the submitted abstracts is crucial for the creation of the new generation of the plasma physicists.« less

Development of a DC Glow Discharge Exhibit for the Demonstration of Plasma Behavior in a Magnetic Field

NASA Astrophysics Data System (ADS)

Bruder, Daniel

2010-11-01

The DC Glow Discharge Exhibit is intended to demonstrate the effects a magnetic field produces on a plasma in a vacuum chamber. The display, which will be featured as a part of The Liberty Science Center's ``Energy Quest Exhibition,'' consists of a DC glow discharge tube and information panels to educate the general public on plasma and its relation to fusion energy. Wall posters and an information booklet will offer brief descriptions of fusion-based science and technology, and will portray plasma's role in the development of fusion as a viable source of energy. The display features a horse-shoe magnet on a movable track, allowing viewers to witness the effects of a magnetic field upon a plasma. The plasma is created from air within a vacuum averaging between 100-200 mTorr. Signage within the casing describes the hardware components. The display is pending delivery to The Liberty Science Center, and will replace a similar, older exhibit presently at the museum.

An Industry Viewpoint on Electron Energy Distribution Function Control

NASA Astrophysics Data System (ADS)

Ventzek, Peter

2011-10-01

It is trite to note that plasmas play a key role in industrial technology. Lighting, laser, film coating and now medical technology require plasma science for their sustenance. One field stands out by virtue of its economic girth and impact. Semiconductor manufacturing and process science enabling its decades of innovation owe significant debt to progress in low temperature plasma science. Today, technology requires atomic level control from plasmas. Mere layers of atoms delineate good and bad device performance. While plasma sources meet nanoscale specifications over 100s cm scale dimensions, achieving atomic level control from plasmas is hindered by the absence of direct control of species velocity distribution functions. EEDF control translates to precise control of species flux and velocities at surfaces adjacent to the plasma. Electron energy distribution function (eedf) control is a challenge that, if successfully met, will have a huge impact on nanoscale device manufacturing. This lunchtime talk will attempt to provide context to the research advances presented at this Workshop. Touched on will be areas of new opportunity and the risks associated with missing these opportunities.

First Observation of a Hall Effect in a Dusty Plasma: A Charged Granular Flow with Relevance to Planetary Rings

NASA Astrophysics Data System (ADS)

Eiskowitz, Skylar; Ballew, Nolan; Rojas, Rubén; Lathrop, Daniel

2017-11-01

The particles in Saturn's rings exhibit complex dynamic behavior. They experience solar radiation pressure, electromagnetic forces, and granular collisions. To investigate the possibility of the Hall Effect in the dusty plasma that comprise Saturn's rings, we have built an experiment that demonstrates the Hall Effect in granular matter. We focus on the Hall Effect because the rings' grains become collisionally charged and experience Saturn's dipolar magnetic field and Lorentz forces as they orbit. The experimental setup includes a closed ring-like track where granular matter is forced to circulate driven by compressed air. The structure sits between two electromagnets so that a portion of the track experiences up to a 0.2 T magnetic field. We vary the strength of the field and the speed of the particles. We report the voltage differences between two conducting plates on opposite sides of the track. If Saturn's rings do experience the Hall Effect, the inside and outside of the rings will develop a charge separation that can lead to a radial electric field and various phenomena including orbital effects due to the additional electric forces. Observational evidence from Cassini suggests that Saturn's rings exhibit lighting, supporting the notion that they are electrically charged. TREND REU program sponsored by the National Science Foundation.

Simulations of ultrafast x-ray laser experiments

NASA Astrophysics Data System (ADS)

Fortmann-Grote, C.; Andreev, A. A.; Appel, K.; Branco, J.; Briggs, R.; Bussmann, M.; Buzmakov, A.; Garten, M.; Grund, A.; Huebl, A.; Jurek, Z.; Loh, N. D.; Nakatsutsumi, M.; Samoylova, L.; Santra, R.; Schneidmiller, E. A.; Sharma, A.; Steiniger, K.; Yakubov, S.; Yoon, C. H.; Yurkov, M. V.; Zastrau, U.; Ziaja-Motyka, B.; Mancuso, A. P.

2017-06-01

Simulations of experiments at modern light sources, such as optical laser laboratories, synchrotrons, and free electron lasers, become increasingly important for the successful preparation, execution, and analysis of these experiments investigating ever more complex physical systems, e.g. biomolecules, complex materials, and ultra-short lived states of matter at extreme conditions. We have implemented a platform for complete start-to-end simulations of various types of photon science experiments, tracking the radiation from the source through the beam transport optics to the sample or target under investigation, its interaction with and scattering from the sample, and registration in a photon detector. This tool allows researchers and facility operators to simulate their experiments and instruments under real life conditions, identify promising and unattainable regions of the parameter space and ultimately make better use of valuable beamtime. In this paper, we present an overview about status and future development of the simulation platform and discuss three applications: 1.) Single-particle imaging of biomolecules using x-ray free electron lasers and optimization of x-ray pulse properties, 2.) x-ray scattering diagnostics of hot dense plasmas in high power laser-matter interaction and identification of plasma instabilities, and 3.) x-ray absorption spectroscopy in warm dense matter created by high energy laser-matter interaction and pulse shape optimization for low-isentrope dynamic compression.

Harmonics generation near ion-cyclotron frequency of ECR plasma

NASA Astrophysics Data System (ADS)

Chowdhury, Satyajit; Biswas, Subir; Chakrabarti, Nikhil; Pal, Rabindranath

2017-10-01

Wave excitation at different frequency regime is employed in the MaPLE device ECR plasma for varied excitation amplitude. At very low amplitude excitation, mainly fundamental frequency mode of the exciter signal frequency comes into play. With the increase in amplitude of applied perturbation, harmonics are generated and dominant over the fundamental frequency mode. There is a fixed critical amplitude of exciter to yield the harmonics and is independent of applied frequency. Observed harmonics and the main frequency mode has propagation characteristics and are discussed here. Exact mode number and propagation nature are also tried to measure in the experiment. Detailed experimental results will be presented. Department of Science and Technology of Government of India (Project No. SB/S2/HEP-005/2014).

Advanced computations in plasma physics

NASA Astrophysics Data System (ADS)

Tang, W. M.

2002-05-01

Scientific simulation in tandem with theory and experiment is an essential tool for understanding complex plasma behavior. In this paper we review recent progress and future directions for advanced simulations in magnetically confined plasmas with illustrative examples chosen from magnetic confinement research areas such as microturbulence, magnetohydrodynamics, magnetic reconnection, and others. Significant recent progress has been made in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics, giving increasingly good agreement between experimental observations and computational modeling. This was made possible by innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales together with access to powerful new computational resources. In particular, the fusion energy science community has made excellent progress in developing advanced codes for which computer run-time and problem size scale well with the number of processors on massively parallel machines (MPP's). A good example is the effective usage of the full power of multi-teraflop (multi-trillion floating point computations per second) MPP's to produce three-dimensional, general geometry, nonlinear particle simulations which have accelerated progress in understanding the nature of turbulence self-regulation by zonal flows. It should be emphasized that these calculations, which typically utilized billions of particles for thousands of time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In general, results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. The associated scientific excitement should serve to stimulate improved cross-cutting collaborations with other fields and also to help attract bright young talent to plasma science.

Advanced Computation in Plasma Physics

NASA Astrophysics Data System (ADS)

Tang, William

2001-10-01

Scientific simulation in tandem with theory and experiment is an essential tool for understanding complex plasma behavior. This talk will review recent progress and future directions for advanced simulations in magnetically-confined plasmas with illustrative examples chosen from areas such as microturbulence, magnetohydrodynamics, magnetic reconnection, and others. Significant recent progress has been made in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics, giving increasingly good agreement between experimental observations and computational modeling. This was made possible by innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales together with access to powerful new computational resources. In particular, the fusion energy science community has made excellent progress in developing advanced codes for which computer run-time and problem size scale well with the number of processors on massively parallel machines (MPP's). A good example is the effective usage of the full power of multi-teraflop MPP's to produce 3-dimensional, general geometry, nonlinear particle simulations which have accelerated progress in understanding the nature of turbulence self-regulation by zonal flows. It should be emphasized that these calculations, which typically utilized billions of particles for tens of thousands time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In general, results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. The associated scientific excitement should serve to stimulate improved cross-cutting collaborations with other fields and also to help attract bright young talent to plasma science.

The America COMPETES Act and the FY2009 Budget

DTIC Science & Technology

2008-10-17

Junior Investigator, Nuclear Physics Outstanding Junior Investigator, Fusion Energy Sciences Plasma Physics Junior Faculty Development; Advanced...Instrumentation Fellowships, and the Fusion Energy Sciences Graduate Fellowships.20 The DOE Summer Institutes authorization in the act is $20 million in FY2009...corresponds to pre-existing High Energy Physics Outstanding Junior Investigator, Nuclear Physics Outstanding Junior Investigator, Fusion Energy Sciences Plasma

Increasing Plasma Parameters using Sheared Flow Stabilization of a Z-Pinch

NASA Astrophysics Data System (ADS)

Shumlak, Uri

2016-10-01

Recent experiments on the ZaP Flow Z-Pinch at the University of Washington have been successful in compressing the plasma column to smaller radii, producing the predicted increases in plasma density (1018 cm-3), temperature (200 eV), and magnetic fields (4 T), while maintaining plasma stability for many Alfven times (over 40 μs) using sheared plasma flows. These results indicate the suitability of the device as a discovery science platform for astrophysical and high energy density plasma research, and keeps open a possible path to achieving burning plasma conditions in a compact fusion device. Long-lived Z-pinch plasmas have been produced with dimensions of 1 cm radius and 100 cm long that are stabilized by sheared axial flows for over 1000 Alfven radial transit times. The observed plasma stability is coincident with the presence of a sheared flow as measured by time-resolved multi-chord ion Doppler spectroscopy applied to impurity ion radiation. These measurements yield insights into the evolution of the velocity profile and show that the stabilizing behavior of flow shear agrees with theoretical calculations and 2-D MHD computational simulations. The flow shear value, extent, and duration are shown to be consistent with theoretical models of the plasma viscosity, which places a design constraint on the maximum axial length of a sheared flow stabilized Z-pinch. Measurements of the magnetic field topology indicate simultaneous azimuthal symmetry and axial uniformity along the entire 100 cm length of the Z-pinch plasma. Separate control of plasma acceleration and compression have increased the accessible plasma parameters and have generated stable plasmas with radii below 0.5 cm, as measured with a high resolution digital holographic interferometer. This work was supported by Grants from U.S. DOE, NNSA, and ARPA-E.

Science Observations of Deep Space One

NASA Technical Reports Server (NTRS)

Nelson, Robert M.; Baganal, Fran; Boice, Daniel C.; Britt, Daniel T.; Brown, Robert H.; Buratti, Bonnie J.; Creary, Frank; Ip, Wing-Huan; Meier, Roland; Oberst, Juergen

1999-01-01

During the Deep Space One (DS1) primary mission, the spacecraft will fly by asteroid 1992 KD and possibly comet Borrelly. There are two technologies being validated on DS1 that will provide science observations of these targets, the Miniature Integrated Camera Spectrometer (MICAS) and the Plasma Experiment for Planetary Exploration (PEPE). MICAS encompasses a camera, an ultraviolet imaging spectrometer and an infrared imaging spectrometer. PEPE combines an ion and electron analyzer designed to determine the three-dimensional distribution of plasma over its field of view. MICAS includes two visible wavelength imaging channels, an ultraviolet imaging spectrometer, and an infrared imaging spectrometer all of which share a single 10-cm diameter telescope. Two types of visible wavelength detectors, both operating between about 500 and 1000 nm are used: a CCD with 13-microrad pixels and an 18-microrad-per-pixel, metal-on-silicon active pixel sensor (APS). Unlike the CCD the APS includes the timing and control electronics on the chip along with the detector. The UV spectrometer spans 80 to 185 nm with 0.64-nm spectral resolution and 316-microrad pixels. The IR spectrometer covers the range from 1200 to 2400 nm with 6.6-nm resolution and 54-microrad pixels PEPE includes a very low-power, low-mass micro-calorimeter to help understand plasma-surface interactions and a plasma analyzer to identify de individual molecules and atoms in the immediate vicinity of the spacecraft that have been eroded off the surface of asteroid 1992 KD. It employs common apertures with separate electrostatic energy analyzers. It measures electron and ion energies spanning a range of 3 eV to 30 keV, with a resolution of five percent. and measures ion mass from one to 135 atomic mass units with 5 percent resolution. It electrostatically sweeps its field of view both in elevation and azimuth. Both MICAS and PEPE represent a new direction for the evolution of science instruments for interplanetary spacecraft. These two instruments incorporate a large fraction of the capability of five instruments that had typically flown on NASA's deep space missions The Deep Space One science team acknowledges the support of Philip Varghese, David H. Lehman, Leslie Livesay, and Marc Rayman for providing invaluable assistance in making the science observations possible.

A perspective on the contributions of Ronald C. Davidson to plasma physics

NASA Astrophysics Data System (ADS)

Wurtele, Jonathan S.

2016-10-01

Starting in the 1960s and continuing for half a century, Ronald C. Davidson made fundamental theoretical contributions to a wide range of areas of pure and applied plasma physics. Davidson was one of the founders of nonneutral plasma physics and a pioneer in developing and applying kinetic theory and nonlinear stability theorems to collective interaction processes and nonlinear dynamics of nonneutral plasmas and intense charged particle beams. His textbooks on nonneutral plasmas are the classic references for the field and educated generations of graduate students. Davidson was a strong advocate for applying the ideas of plasma theory to develop techniques that benefit other branches of science. For example, one of the major derivative fields enabled by nonneutral plasmas is the study of antimatter plasmas and the synthesis of antihydrogen. This talk will review a few highlights of Ronald Davidson's impact on plasma physics and related fields of science.

The diverse applications of plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Mukul, E-mail: mukulsharma@acropolis.edu.in; Darwhekar, Gajanan, E-mail: gdarwhekar@acropolis.edu.in; Dubey, Shivani, E-mail: dubeyshivani08@rediffmail.com

Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteriamore » and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.« less

The diverse applications of plasma

NASA Astrophysics Data System (ADS)

Sharma, Mukul; Dubey, Shivani; Darwhekar, Gajanan; Jain, Sudhir Kumar

2015-07-01

Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

An Explorative Study to Use DBD Plasma Generation for Aircraft Icing Mitigation

NASA Astrophysics Data System (ADS)

Hu, Hui; Zhou, Wenwu; Liu, Yang; Kolbakir, Cem

2017-11-01

An explorative investigation was performed to demonstrate the feasibility of utilizing thermal effect induced by Dielectric-Barrier-Discharge (DBD) plasma generation for aircraft icing mitigation. The experimental study was performed in an Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT). A NACA0012 airfoil/wing model embedded with DBD plasma actuators was installed in ISU-IRT under typical glaze icing conditions pertinent to aircraft inflight icing phenomena. While a high-speed imaging system was used to record the dynamic ice accretion process over the airfoil surface for the test cases with and without switching on the DBD plasma actuators, an infrared (IR) thermal imaging system was utilized to map the corresponding temperature distributions to quantify the unsteady heat transfer and phase changing process over the airfoil surface. The thermal effect induced by DBD plasma generation was demonstrated to be able to keep the airfoil surface staying free of ice during the entire ice accretion experiment. The measured quantitative surface temperature distributions were correlated with the acquired images of the dynamic ice accretion and water runback processes to elucidate the underlying physics. National Science Foundation CBET-1064196 and CBET-1435590.

SciDAC GSEP: Gyrokinetic Simulation of Energetic Particle Turbulence and Transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Zhihong

Energetic particle (EP) confinement is a key physics issue for burning plasma experiment ITER, the crucial next step in the quest for clean and abundant energy, since ignition relies on self-heating by energetic fusion products (α-particles). Due to the strong coupling of EP with burning thermal plasmas, plasma confinement property in the ignition regime is one of the most uncertain factors when extrapolating from existing fusion devices to the ITER tokamak. EP population in current tokamaks are mostly produced by auxiliary heating such as neutral beam injection (NBI) and radio frequency (RF) heating. Remarkable progress in developing comprehensive EP simulationmore » codes and understanding basic EP physics has been made by two concurrent SciDAC EP projects GSEP funded by the Department of Energy (DOE) Office of Fusion Energy Science (OFES), which have successfully established gyrokinetic turbulence simulation as a necessary paradigm shift for studying the EP confinement in burning plasmas. Verification and validation have rapidly advanced through close collaborations between simulation, theory, and experiment. Furthermore, productive collaborations with computational scientists have enabled EP simulation codes to effectively utilize current petascale computers and emerging exascale computers. We review here key physics progress in the GSEP projects regarding verification and validation of gyrokinetic simulations, nonlinear EP physics, EP coupling with thermal plasmas, and reduced EP transport models. Advances in high performance computing through collaborations with computational scientists that enable these large scale electromagnetic simulations are also highlighted. These results have been widely disseminated in numerous peer-reviewed publications including many Phys. Rev. Lett. papers and many invited presentations at prominent fusion conferences such as the biennial International Atomic Energy Agency (IAEA) Fusion Energy Conference and the annual meeting of the American Physics Society, Division of Plasma Physics (APS-DPP).« less

JPRS Report, Science & Technology, USSR: Space Biology & Aerospace Medicine, Vol. 21, No. 3, May-June 1987

DTIC Science & Technology

1988-01-12

suffi- cient signal power (no more than 50 mW) [8, 18, 19, 35, 39]. Use of electric stimulation at subliminal levels of above current has a tonic...in the case of a manganese-deficient diet [57]. Retarded growth and sexual maturation, diminished concentration of zinc in plasma, red blood cells...metalloenzymes, stimulating effect on blood-forming organs, hemopoiesis and other functions. Our chronic experiments on animals and observations of

Laser-driven ion acceleration at BELLA

NASA Astrophysics Data System (ADS)

Bin, Jianhui; Steinke, Sven; Ji, Qing; Nakamura, Kei; Treffert, Franziska; Bulanov, Stepan; Roth, Markus; Toth, Csaba; Schroeder, Carl; Esarey, Eric; Schenkel, Thomas; Leemans, Wim

2017-10-01

BELLA is a high repetiton rate PW laser and we used it for high intensity laser plasma acceleration experiments. The BELLA-i program is focused on relativistic laser plasma interaction such as laser driven ion acceleration, aiming at establishing an unique collaborative research facility providing beam time to selected external groups for fundamental physics and advanced applications. Here we present our first parameter study of ion acceleration driven by the BELLA-PW laser with truly high repetition rate. The laser repetition rate of 1Hz allows for scanning the laser pulse duration, relative focus location and target thickness for the first time at laser peak powers of above 1 PW. Furthermore, the long focal length geometry of the experiment (f ∖65) and hence, large focus size provided ion beams of reduced divergence and unprecedented charge density. This work was supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

Near equality of ion phase space densities at earth, Jupiter, and Saturn

NASA Technical Reports Server (NTRS)

Cheng, A. F.; Krimigis, S. M.; Armstrong, T. P.

1985-01-01

Energetic-ion phase-space density profiles are strikingly similar in the inner magnetospheres of earth, Jupiter, and Saturn for ions of first adiabatic invariant near 100 MeV/G and small mirror latitudes. Losses occur inside L approximately equal to 7 for Jupiter and Saturn and inside L approximately equal to 5 at earth. At these L values there exist steep plasma-density gradients at all three planets, associated with the Io plasma torus at Jupiter, the Rhea-Dione-Tethys torus at Saturn, and the plasmasphere at earth. Measurements of ion flux-tube contents at Jupiter and Saturn by the low-energy charged-particle experiment show that these are similar (for O ions at L = 5-9) to those at earth (for protons at L = 2-6). Furthermore, the thermal-ion flux-tube contents from Voyager plasma-science data at Jupiter and Saturn are also very nearly equal, and again similar to those at earth, differing by less than a factor of 3 at the respective L values. The near equality of energetic and thermal ion flux-tube contents at earth, Jupiter, and Saturn suggests the possibility of strong physical analogies in the interaction between plasma and energetic particles at the plasma tori/plasma sheets of Jupiter and Saturn and the plasmasphere of earth.

Key and Driving Requirements for the Juno Payload of Instruments

NASA Technical Reports Server (NTRS)

Dodge, Randy; Boyles, Mark A.; Rasbach, Chuck E.

2007-01-01

The Juno Mission was selected in the summer of 2005 via NASA's New Frontiers competitive AO process (refer to http://www.nasa.gov/home/hqnews/2005/jun/HQ_05138_New_Frontiers_2.html). The Juno project is led by a Principle Investigator based at Southwest Research Institute [SwRI] in San Antonio, Texas, with project management based at the Jet Propulsion Laboratory [JPL] in Pasadena, California, while the Spacecraft design and Flight System Integration are under contract to Lockheed Martin Space Systems Company [LM-SSC] in Denver, Colorado. the payload suite consists of a large number of instruments covering a wide spectrum of experimentation. The science team includes a lead Co-investigator for each one of the following experiments: A Magnetometer experiment (consisting of both a FluxGate Magnetometer (FGM) built at Goddard Space Flight Center GSFC] and a Scalar Helium Magnetometer (SHM) built at JPL, a MicroWave Radiometer (MWR) also built at JPL, a Gravity Science experiment (GS) implemented via the telecom subsystem, two complementary particle instruments (Jovian Auroral Distribution Experiment, JADE developed by SwRI and Juno Energetic-particle Detector Instrument, JEDI from the Applied Physics Lab (APL)--JEDI and JADE both measure electrons and ions), an Ultraviolet Spectrometer (UVS) also developed at SwRI, and a radio and plasma (WAVES) experiment (from the University of Iowa). In addition, a visible camera (JunoCam) is included in the payload to facilitate education and public outreach (designed & fabricated by Malin Space Science Systems [MSSS]).

The Integrated Plasma Simulator: A Flexible Python Framework for Coupled Multiphysics Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foley, Samantha S; Elwasif, Wael R; Bernholdt, David E

2011-11-01

High-fidelity coupled multiphysics simulations are an increasingly important aspect of computational science. In many domains, however, there has been very limited experience with simulations of this sort, therefore research in coupled multiphysics often requires computational frameworks with significant flexibility to respond to the changing directions of the physics and mathematics. This paper presents the Integrated Plasma Simulator (IPS), a framework designed for loosely coupled simulations of fusion plasmas. The IPS provides users with a simple component architecture into which a wide range of existing plasma physics codes can be inserted as components. Simulations can take advantage of multiple levels ofmore » parallelism supported in the IPS, and can be controlled by a high-level ``driver'' component, or by other coordination mechanisms, such as an asynchronous event service. We describe the requirements and design of the framework, and how they were implemented in the Python language. We also illustrate the flexibility of the framework by providing examples of different types of simulations that utilize various features of the IPS.« less

Towards a better understanding of high-energy electron pitch-angle scattering by electromagnetic ion cyclotron waves

NASA Astrophysics Data System (ADS)

Vincena, S.; Gekelman, W.; Pribyl, P.; Tang, S., W.,; Papadopoulos, K.

2017-10-01

Shear Alfven waves are a fundamental mode in magnetized plasmas. Propagating near the ion cyclotron frequency, these waves are often termed electromagnetic ion cyclotron (EMIC) waves and can involve multiple ion species. Near the earth, for example, the wave may interact resonantly with oxygen ions at altitudes ranging from 1000 to 2000 km. The waves may either propagate from space towards the earth (possibly involving mode conversion), or be generated by RF transmitters on the ground. These preliminary experiments are motivated by theoretical predictions that such waves can pitch-angle scatter relativistic electrons trapped in the earth's dipole field. EMIC waves are launched in the Large Plasma Device at UCLA's Basic Plasma Science Facility in plasmas with single and multiple ion species into magnetic field gradients where ion cyclotron resonance is satisfied. We report here on the frequency and k-spectra in the critical layer and how they compare with theoretical predictions in computing an effective diffusion coefficient for high-energy electrons. Funding is provided by the NSF, DoE, and AFSOR.

On the magnetized disruption of inertially-confined plasma flows

NASA Astrophysics Data System (ADS)

Manuel, Mario; Kuranz, Carolyn; Rasmus, Alexander; Klein, Sallee; MacDonald, Michael; Trantham, Matt; Fein, Jeff; Belancourt, Patrick; Young, Rachel; Keiter, Paul; Drake, R. Paul; Pollock, Brad; Park, Jaebum; Hazi, Andrew; Williams, Jackson; Chen, Hui

2016-10-01

The creation and disruption of inertially-collimated plasma flows is investigated through experiment, simulation, and analytical modeling. Laser-generated plasma-jets are shown to be disrupted by an applied 5T B-field along the jet axis. An analytical model of the system describes the disruption mechanism through the competing effects of B-field advection and diffusion. These results indicate that for Rem 10-100, the ratio of inertial to magnetic pressures plays an important role in determining whether a jet is formed, but at high enough Rem , axial B-field amplification prevents inertial collimation altogether. This work is funded by the U.S. DOE, through the NNSA-DS and SC-OFES Joint Program in HED Laboratory Plasmas, Grant Number DE-NA0001840 and in collaboration with LLNL under contract DE-AC52-07NA27344. Support for this work was provided by NASA, under contract NAS8-03060, through Einstein Postdoctoral Fellowship Grant Number PF3-140111. Software used in this work was developed in part by the DOE NNSA ASC- and DOE Office of Science ASCR-supported Flash Center.

Pulsed Polarimetry and magnetic sensing on the Magnetized Shock Experiment (MSX)

NASA Astrophysics Data System (ADS)

Smith, R. J.; Hutchinson, T. M.; Weber, T. E.; Taylor, S. F.; Hsu, S. C.

2014-10-01

MSX is uniquely positioned to generate the conditions for collision-less magnetized supercritical shocks with Alvenic Mach numbers (MA) of the order 10 and higher. Significant operational strides have been made in forming plasmas over wide parameter ranges: (Te + Ti) of 10-200 eV, average neof 5-60×10+21 m-3, speeds up to 150 km/s and fields up to 1T with a highest plasma flow MA of 5 to date. The MSX plasma is unique in regards to large plasma size of 10 cm and average β higher than 0.8 making the FRC and the magnetized shock structure candidates for the application of Pulsed Polarimetry, a polarization sensitive Lidar technique. The shock dynamics are presently being investigated using internal probes, interferometry and imaging. Internal probe results and an assessment of the shock parameters will dictate the use of the UW pulsed polarimeter system in which internal ne, Teand B are to be measured. Recent results will be presented. Supported by DOE Office of Fusion Energy Sciences Funding DE-FOA-0000755.

Ionospheric Research with Miniaturized Plasma Sensors Aboard FalconSAT-3

NASA Astrophysics Data System (ADS)

Habash Krause, L.; Herrero, F. A.; Chun, F. K.; McHarg, M. G.

2003-12-01

Investigations into a novel technique to measure ionosphere-thermosphere parameters have culminated in the Flat Plasma Spectrometer (FLAPS) experiment, presently under development through a collaboration between NASA Goddard Space Flight Center (GSFC) and the U. S. Air Force Academy (USAFA). FLAPS is capable of providing measurements of the full neutral wind vector, full ion-drift velocity vector, neutral and ion temperatures, and deviations from thermalization. In addition, coarse mass spectroscopy is possible using an energy analysis technique. The suite of instruments is comprised of a set of 16 individual neutral and ion analyzers, each of which is designed to perform a specific function. Advances in miniaturization technology have enabled a design in which the 16-sensor suite resides on a circular microchannel plate with an effective area of 25 cm2. The FLAPS electronics package, consisting of low voltage and high voltage power supplies, a microprocessor, and Application Specific Integrated Circuit (ASIC) amplifiers, requires a volume of 290 cm3, power of 1.5 W, and a mass of 500 g. The suite requires a +5V regulated power line from the spacecraft, and the telemetry interface is a 5.0 V TTL-compatible serial connection. Data collection rates vary from 1 to 1000 (192 Byte) spectra per second. The motivation for the FLAPS experiment is driven by objectives that fall into both basic science and technology demonstration categories. Scientifically, there is strong interest in the effects of ionosphere-thermosphere coupling and non-thermalized plasma on the processes associated with equatorial F-region ionospheric plasma bubbles. These bubbles have been known to scintillate transionospheric propagation of radio waves, often resulting in disruptions of space-based communication and navigation systems. FLAPS investigations will assist in quantifying the impact of various processes on the instigation or suppression of plasma bubbles; certain outstanding questions include 1) What is the relevance of meridional winds in suppression of plasma bubble growth? 2) What role does a velocity space instability driven by non-thermalized plasma play in the generation of small scale (<1 km) bubbles? 3) What process is responsible for turbulence in plasma beyond the edges of a bubble structure? Technologically, the need for small yet capable instruments arises from the desire to make multipoint in situ measurements of "microscopic" plasma parameters to provide insight into "macroscopic" phenomena. Examples include coherency of spatial boundaries of large-scale ( ˜100 km) plasma bubbles, three dimensional structure of the equatorial wind and temperature anomaly, and vertical velocity gradients in the low latitude ionosphere. This paper provides an overview of the experiment motivation and instrument design of the FLAPS experiment.

The National Ignition Facility: Transition to a User Facility

NASA Astrophysics Data System (ADS)

Moses, E. I.; Atherton, J.; Lagin, L.; Larson, D.; Keane, C.; MacGowan, B.; Patterson, R.; Spaeth, M.; Van Wonterghem, B.; Wegner, P.; Kauffman, R.

2016-03-01

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) has been operational since March 2009 and has been transitioning to a user facility supporting ignition science, high energy density science (HEDS), national security applications, and fundamental science. The facility has achieved its design goal of 1.8 MJ and 500 TW of 3ω light on target, and has performed target experiments with 1.9 MJ at peak powers of 410 TW. The facility is on track to perform over 200 target shots this year in support of all of its user communities. The facility has nearly 60 diagnostic systems operational and has shown flexibility in laser pulse shape and performance to meet the requirements of its multiple users. Progress continues on its goal of demonstrating thermonuclear burn in the laboratory. It has performed over 40 indirect-drive experiments with cryogenic-layered capsules. New platforms are being developed for HEDS and fundamental science. Equation-of-state and material strength experiments have been done on a number of materials with pressures of over 50 MBars obtained in diamond, conditions never previously encountered in the laboratory and similar to those found in planetary interiors. Experiments are also in progress investigating radiation transport, hydrodynamic instabilities, and direct drive implosions. NIF continues to develop as an experimental facility. Advanced Radiographic Capability (ARC) is now being installed on NIF for producing high-energy radiographs of the imploded cores of ignition targets and for short pulse laser-plasma interaction experiments. One NIF beam is planned for conversion to two picosecond beams in 2014. Other new diagnostics such as x-ray Thomson scattering, low energy neutron spectrometer, and multi-layer reflecting x-ray optics are also planned. Incremental improvements in laser performance such as improved optics damage performance, beam balance, and back reflection control are being pursued.

Laboratory Simulations of CME-Solar Wind Interactions Using a Coaxial Gun and Background Plasma

NASA Astrophysics Data System (ADS)

Wallace, B. H.; Zhang, Y.; Fisher, D.; Gilmore, M.

2016-12-01

Understanding and predicting solar coronal mass ejections (CMEs) is of critical importance for mitigating their disruptive behavior on ground- and space-based technologies. While predictive models of CME propagation and evolution have relied primarily on sparse in-situ data along with ground and satellite images for validation purposes, emerging laboratory efforts have shown that CME-like events can be created with parameters applicable to the solar regime that may likewise aid in predictive modeling. A modified version of the coaxial plasma gun from the Plasma Bubble Expansion Experiment (PBEX) [A. G. Lynn, Y. Zhang, S. C. Hsu, H. Li, W. Liu, M. Gilmore, and C. Watts, Bull. Amer. Phys. Soc. 52, 53 (2007)] will be used in conjunction with the Helicon-Cathode (HelCat) basic plasma science device in order to observe the magnetic characteristics of CMEs as they propagate through the solar wind. The evolution of these interactions will be analyzed using a multi-tip Langmuir probe array, a 33-position B-dot probe array, and a high speed camera. The results of this investigation will be used alongside the University of Michigan's BATS-R-US 3-D MHD numerical code, which will be used to perform simulations of the coaxial plasma gun experiment. The results of these two approaches will be compared in order to validate the capabilities of the BATS-R-US code as well as to further our understanding of magnetic reconnection and other processes that take place as CMEs propagate through the solar wind. The details of the experimental setup as well as the analytical approach are discussed.

Wind tunnel experiments on flow separation control of an Unmanned Air Vehicle by nanosecond discharge plasma aerodynamic actuation

NASA Astrophysics Data System (ADS)

Kang, Chen; Hua, Liang

2016-02-01

Plasma flow control (PFC) is a new kind of active flow control technology, which can improve the aerodynamic performances of aircrafts remarkably. The flow separation control of an unmanned air vehicle (UAV) by nanosecond discharge plasma aerodynamic actuation (NDPAA) is investigated experimentally in this paper. Experimental results show that the applied voltages for both the nanosecond discharge and the millisecond discharge are nearly the same, but the current for nanosecond discharge (30 A) is much bigger than that for millisecond discharge (0.1 A). The flow field induced by the NDPAA is similar to a shock wave upward, and has a maximal velocity of less than 0.5 m/s. Fast heating effect for nanosecond discharge induces shock waves in the quiescent air. The lasting time of the shock waves is about 80 μs and its spread velocity is nearly 380 m/s. By using the NDPAA, the flow separation on the suction side of the UAV can be totally suppressed and the critical stall angle of attack increases from 20° to 27° with a maximal lift coefficient increment of 11.24%. The flow separation can be suppressed when the discharge voltage is larger than the threshold value, and the optimum operation frequency for the NDPAA is the one which makes the Strouhal number equal one. The NDPAA is more effective than the millisecond discharge plasma aerodynamic actuation (MDPAA) in boundary layer flow control. The main mechanism for nanosecond discharge is shock effect. Shock effect is more effective in flow control than momentum effect in high speed flow control. Project supported by the National Natural Science Foundation of China (Grant Nos. 61503302, 51207169, and 51276197), the China Postdoctoral Science Foundation (Grant No. 2014M562446), and the Natural Science Foundation of Shaanxi Province, China (Grant No. 2015JM1001).

Electrodynamic Tethers and E-Sails as Active Experiment Testbeds and Technologies in Space

NASA Astrophysics Data System (ADS)

Gilchrist, B. E.; Wiegmann, B.; Johnson, L.; Bilen, S. G.; Habash Krause, L.; Miars, G.; Leon, O.

2017-12-01

The use of small-to-large flexible structures in space such as tethers continues to be studied for scientific and technology applications. Here we will consider tether electrodynamic and electrostatic interactions with magneto-plasmas in ionospheres, magnetospheres, and interplanetary space. These systems are enabling fundamental studies of basic plasma physics phenomena, allowing direct studies of the space environment, and generating technological applications beneficial for science missions. Electrodynamic tethers can drive current through the tether based on the Lorenz force adding or extracting energy from its orbit allowing for the study of charged bodies or plasma plumes moving through meso-sonic magnetoplasmas [1]. Technologically, this also generates propulsive forces requiring no propellant and little or no consumables in any planetary system with a magnetic field and ionosphere, e.g., Jupiter [2]. Further, so called electric sails (E-sails) are being studied to provide thrust through momentum exchange with the hypersonic solar wind. The E-sail uses multiple, very long (10s of km) charged, mostly bare rotating conducting tethers to deflect solar wind protons. It is estimated that a spacecraft could achieve a velocity over 100 km/s with time [3,4]. 1. Banks, P.M., "Review of electrodynamic tethers for space plasma science," J. Spacecraft and Rockets, vol. 26, no. 4, pp. 234-239, 1989. 2. Talley, C., J. Moore, D. Gallagher, and L. Johnson, "Propulsion and power from a rotating electrodynamic tether at Jupiter," 38th AIAA Aerospace Sciences Meeting and Exhibit, January 2000. 3. Janhunen, P., "The electric sail—A new propulsion method which may enable fast missions to the outer solar system," J. British Interpl. Soc., vol. 61, no. 8, pp. 322-325, 2008. 4. Wiegman, B., T. Scheider, A. Heaton, J. Vaughn, N. Stone, and K. Wright, "The Heliopause Electrostatic Rapid Transit System (HERTS)—Design, trades, and analyses performed in a two-year NASA investigation of electric sail propulsion systems," 53rd AIAA/SAE/ASEE Joint Propulsion Conf., 10-12 July 2017, Atlanta, GA.

Influence of the solar wind/interplanetary medium on Saturnian kilometric radiation

NASA Technical Reports Server (NTRS)

Rucker, Helmut O.; Desch, M. D.

1990-01-01

Previous studies on the periodicities of the Saturnian kilometric radiation (SKR) suggested a considerable solar wind influence on the occurrence of SKR, so it was obvious to investigate the relationship between parameters of the solar wind/interplanetary medium and this Saturnian radio component. Voyager 2 data from the Plasma Science experiment, the Magnetometer experiment and the Planetary Radio Astronomy experiment were used to analyze the external control of SKR. Out of the examined quantities known to be important in controlling magnetospheric processes this investigation yielded a dominance of the solar wind momentum, ram pressure and kinetic energy flux, in stimulating SKR and controlling its activity and emitted energy, and confirmed the results of the Voyager 1 analysis.

Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, Juergen; Aaron, A. M.; Bell, Gary L.

2015-10-20

Fusion energy is the most promising energy source for the future, and one of the most important problems to be solved progressing to a commercial fusion reactor is the identification of plasma-facing materials compatible with the extreme conditions in the fusion reactor environment. The development of plasma–material interaction (PMI) science and the technology of plasma-facing components are key elements in the development of the next step fusion device in the United States, the so-called Fusion Nuclear Science Facility (FNSF). All of these PMI issues and the uncertain impact of the 14-MeV neutron irradiation have been identified in numerous expert panelmore » reports to the fusion community. The 2007 Greenwald report classifies reactor plasma-facing materials (PFCs) and materials as the only Tier 1 issues, requiring a “. . . major extrapolation from the current state of knowledge, need for qualitative improvements and substantial development for both the short and long term.” The Greenwald report goes on to list 19 gaps in understanding and performance related to the plasma–material interface for the technology facilities needed for DEMO-oriented R&D and DEMO itself. Of the 15 major gaps, six (G7, G9, G10, G12, G13) can possibly be addressed with ORNL’s proposal of an advanced Material Plasma Exposure eXperiment. Establishing this mid-scale plasma materials test facility at ORNL is a key element in ORNL’s strategy to secure a leadership role for decades of fusion R&D. That is to say, our end goal is to bring the “signature facility” FNSF home to ORNL. This project is related to the pre-conceptual design of an innovative target station for a future Material–Plasma Exposure eXperiment (MPEX). The target station will be designed to expose candidate fusion reactor plasma-facing materials and components (PFMs and PFCs) to conditions anticipated in fusion reactors, where PFCs will be exposed to dense high-temperature hydrogen plasmas providing steady-state heat fluxes of 5–20 MW/m 2 and ion fluxes up to 10 24 m -2s -1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.« less

Control of ROS and RNS productions in liquid in atmospheric pressure plasma-jet system

NASA Astrophysics Data System (ADS)

Uchida, Giichiro; Ito, Taiki; Takenaka, Kosuke; Ikeda, Junichiro; Setsuhara, Yuichi

2016-09-01

Non-thermal plasma jets are of current interest in biomedical applications such as wound disinfection and even treatment of cancer tumors. Beneficial therapeutic effects in medical applications are attributed to excited species of oxygen and nitrogen from air. However, to control the production of these species in the plasma jet is difficult because their production is strongly dependent on concentration of nitrogen and oxygen from ambient air into the plasma jet. In this study, we analyze the discharge characteristics and the ROS and RNS productions in liquid in low- and high-frequency plasma-jet systems. Our experiments demonstrated the marked effects of surrounding gas near the plasma jet on ROS and RNS productions in liquid. By controlling the surround gas, the O2 and N2 main plasma jets are selectively produced even in open air. We also show that the concentration ratio of NO2- to H2O2 in liquid is precisely tuned from 0 to 0.18 in deionized water by changing N2 gas ratio (N2 / (N2 +O2)) in the main discharge gas, where high NO2- ratio is obtained at N2 gas ratio at N2 / (N2 +O2) = 0 . 8 . The low-frequency plasma jet with controlled surrounding gas is an effective plasma source for ROS and RNS productions in liquid, and can be a useful tool for biomedical applications. This study was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas ``Plasma Medical Innovation'' (24108003) from the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT).

Feasibility Study for a Plasma Dynamo Facility to Investigate Fundamental Processes in Plasma Astrophysics. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forest, Cary B.

The scientific equipment purchased on this grant was used on the Plasma Dynamo Prototype Experiment as part of Professor Forest's feasibility study for determining if it would be worthwhile to propose building a larger plasma physics experiment to investigate various fundamental processes in plasma astrophysics. The initial research on the Plasma Dynamo Prototype Experiment was successful so Professor Forest and Professor Ellen Zweibel at UW-Madison submitted an NSF Major Research Instrumentation proposal titled "ARRA MRI: Development of a Plasma Dynamo Facility for Experimental Investigations of Fundamental Processes in Plasma Astrophysics." They received funding for this project and the Plasma Dynamomore » Facility also known as the "Madison Plasma Dynamo Experiment" was constructed. This experiment achieved its first plasma in the fall of 2012 and U.S. Dept. of Energy Grant No. DE-SC0008709 "Experimental Studies of Plasma Dynamos," now supports the research.« less

PREFACE: VI Scientific Technical Conference on "Low-temperature plasma during the deposition of functional coatings"

NASA Astrophysics Data System (ADS)

2014-11-01

The VI Republican Scientific Technical Conference "Low-temperature plasma during the deposition of functional coatings" took place from 4 to 7 November 2014 at the Academy of Sciences of the Republic of Tatarstan and the Kazan Federal University. The conference was chaired by a Member of the Academy of Sciences of the Republic of Tatarstan Nail Kashapov -Professor, Doctor of Technical Sciences- a member of the Scientific and Technical Council of the Ministry of Economy of the Republic of Tatarstan. At the conference, the participants discussed a wide range of issues affecting the theoretical and computational aspects of research problems in the physics and technology of low-temperature plasma. A series of works were devoted to the study of thin films obtained by low-temperature plasma. This year work dedicated to the related field of heat mass transfer in multiphase media and low-temperature plasma was also presented. Of special interest were reports on the exploration of gas discharges with liquid electrolytic electrotrodes and the study of dusty plasmas. Kashapov Nail, D.Sc., Professor (Kazan Federal University)

Survey of Voyager plasma science ions at Jupiter: 1. Analysis method

NASA Astrophysics Data System (ADS)

Bagenal, F.; Dougherty, L. P.; Bodisch, K. M.; Richardson, J. D.; Belcher, J. M.

2017-08-01

The Voyagers 1 and 2 spacecraft flew by Jupiter in March and July of 1979, respectively. The Plasma Science instrument (PLS) acquired detailed measurements of the plasma environment in the equatorial region of the magnetosphere between 4.9 and 4 RJ. While bulk plasma properties such as charge density, ion temperature, and bulk flow were reasonably well determined, the ion composition was only well constrained in occasional regions of cold plasma. The ion data obtained by the PLS instrument have been reanalyzed using physical chemistry models to constrain the composition and reduce the number of free parameters, particularly in regions of hotter plasma. This paper describes the method used for fitting the plasma data and presents the results versus time. Two companion papers describe the composition of heavy ions and present analysis of protons plus other minor ions.

Plasma Display at the Liberty Science Center

NASA Astrophysics Data System (ADS)

Bruder, Dan; Gilligan, Nick; Tarman, Lisa; Ferris, Pamella; Morgan, James; Delooper, John; Zwicker, Andrew

2009-11-01

The Liberty Science Center (LSC) is the largest (300,000 sq. ft.) education resource in the New Jersey -- New York City region. PPPL in collaboration with the LSC has had a display at the center since 2007 More than 1.5 million visitors have come to the museum since the plasma display has been introduced. The plasma display has had significant use during that time frame. During the summer of 2009 a redesigned plasma exhibit was created by a student teacher-team using the lessons learned from the existing exhibit. The display includes a DC glow discharge tube with a permanent external magnet allowing visitors to manipulate the plasma and see how plasma can be used for fusion research. The goal of the display is to allow an individual to see a plasma and understand the potential benefits of fusion energy.

Plasma Processing with a One Atmosphere Uniform Glow Discharge Plasma (OAUGDP)

NASA Astrophysics Data System (ADS)

Reece Roth, J.

2000-10-01

The vast majority of all industrial plasma processing is conducted with glow discharges at pressures below 10 torr. This has limited applications to high value workpieces as a result of the large capital cost of vacuum systems and the production constraints of batch processing. It has long been recognized that glow discharges would play a much larger industrial role if they could be operated at one atmosphere. The One Atmosphere Uniform Glow Discharge Plasma (OAUGDP) has been developed at the University of Tennessee Plasma Sciences Laboratory. The OAUGDP is non-thermal RF plasma with the time-resolved characteristics of a classical low pressure DC normal glow discharge. An interdisciplinary team was formed to conduct exploratory investigations of the physics and applications of the OAUGDP. This team includes collaborators from the UTK Textiles and Nonwovens Development Center (TANDEC) and the Departments of Electrical and Computer Engineering, Microbiology, Food Science and Technology, and Mechanical and Aerospace Engineering and Engineering Science. Exploratory tests were conducted on a variety of potential plasma processing and other applications. These include the use of OAUGDP to sterilize medical and dental equipment and air filters; diesel soot removal; plasma aerodynamic effects; electrohydrodynamic (EDH) flow control of the neutral working gas; increasing the surface energy of materials; increasing the wettability and wickability of fabrics; and plasma deposition and directional etching. A general overview of these topics will be presented.

Compact gain saturated plasma based X-ray lasers down to 6.9nm

NASA Astrophysics Data System (ADS)

Rocca, Jorge; Wang, Y.; Wang, S.; Rockwood, A.; Berrill, M.; Shlyaptsev, V.

2017-10-01

Plasma based soft x-ray amplifiers allow many experiments requiring bright, high energy soft x-ray laser pulses to be conducted in compact facilities. We have extended the wavelength of compact gain saturated x-ray lasers to 6.89 nm in a Ni-like Gd plasma generated by a Ti:Sa laser. Gain saturated laser operation was also obtained at 7.36 nm in Ni-like Sm. Isolectronic scaling and optimization of laser pre-pulse duration allowed us to also observe strong lasing at 6.6 nm and 6.1 nm in Ni-like Tb, and amplification at 6.4 nm and 5.89 nm in Ni-like Dy. The results were obtained by transient laser heating of solid targets with traveling wave excitation at progressively increased gracing incidence angles. We show that the optimum pump angle of incidence for collisional Ni-like lasers increases linearly with atomic number from Z =42 to Z =66, reaching 43 degrees for Ni-like Dy, in good agreement with hydrodynamic/atomic physics simulations. These results will enable single-shot nano-scale imaging and other application of sub-7 nm lasers to be performed at compact facilities. Work supported by Grant DE-FG02-4ER15592 of the Department of Energy, Office of Science, and by the National Science Foundation Grant ECCS 1509925.

Rare isotope accelerator project in Korea and its application to high energy density sciences

NASA Astrophysics Data System (ADS)

Chung, M.; Chung, Y. S.; Kim, S. K.; Lee, B. J.; Hoffmann, D. H. H.

2014-01-01

As a national science project, the Korean government has recently established the Institute for Basic Science (IBS) with the goal of conducting world-class research in basic sciences. One of the core facilities for the IBS will be the rare isotope accelerator which can produce high-intensity rare isotope beams to investigate the fundamental properties of nature, and also to support a broad research program in material sciences, medical and biosciences, and future nuclear energy technologies. The construction of the accelerator is scheduled to be completed by approximately 2017. The design of the accelerator complex is optimized to deliver high average beam current on targets, and to maximize the production of rare isotope beams through the simultaneous use of Isotope Separation On-Line (ISOL) and In-Flight Fragmentation (IFF) methods. The proposed accelerator is, however, not optimal for high energy density science, which usually requires very high peak currents on the target. In this study, we present possible beam-plasma experiments that can be done within the scope of the current accelerator design, and we also investigate possible future extension paths that may enable high energy density science with intense pulsed heavy ion beams.

Utilizing Social Media and Blogging to Teach Science Communication

NASA Astrophysics Data System (ADS)

Keesee, A. M.

2012-12-01

The National Science Foundation presented the Science: Becoming the Messenger Workshop at my university in Fall 2011. Following the workshop, I started a blog (http://plasma.physics.wvu.edu/), Facebook page (WVU Plasma Physics), and Twitter feed (@WVUPlasma) to promote the West Virginia University Plasma Physics Research Groups. Faculty, postdocs, and graduate students in plasma physics are assigned the task of writing a blog post on a rotating basis as one of three elements for our monthly Journal Club. Our Facebook page and Twitter feed are used to announce new blog posts and accomplishments by group members. We have found this process to be a good way for students to learn to describe their research to people outside of their field of expertise. Details on establishing and maintaining these resources and specific examples will be presented. Follow me @plasmaphysmom.

Experiment to Form and Characterize a Section of a Spherically Imploding Plasma Liner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, S. C.; Langendorf, S. J.; Yates, K. C.

Here, we describe an experiment to form and characterize a section of a spherically imploding plasma liner by merging six supersonic plasma jets that are launched by newly designed contoured-gap coaxial plasma guns. This experiment is a prelude to forming a fully spherical imploding plasma liner using many dozens of plasma guns, as a standoff driver for plasma-jet-driven magneto-inertial fusion. The objectives of the six-jet experiments are to assess the evolution and scalings of liner Mach number and uniformity, which are important metrics for spherically imploding plasma liners to compress magnetized target plasmas to fusion conditions. Lastly, this article describesmore » the design of the coaxial plasma guns, experimental characterization of the plasma jets, six-jet experimental setup and diagnostics, initial diagnostic data from three- and six-jet experiments, and the high-level objectives of associated numerical modeling.« less

Experiment to Form and Characterize a Section of a Spherically Imploding Plasma Liner

DOE PAGES

Hsu, S. C.; Langendorf, S. J.; Yates, K. C.; ...

2017-12-18

Here, we describe an experiment to form and characterize a section of a spherically imploding plasma liner by merging six supersonic plasma jets that are launched by newly designed contoured-gap coaxial plasma guns. This experiment is a prelude to forming a fully spherical imploding plasma liner using many dozens of plasma guns, as a standoff driver for plasma-jet-driven magneto-inertial fusion. The objectives of the six-jet experiments are to assess the evolution and scalings of liner Mach number and uniformity, which are important metrics for spherically imploding plasma liners to compress magnetized target plasmas to fusion conditions. Lastly, this article describesmore » the design of the coaxial plasma guns, experimental characterization of the plasma jets, six-jet experimental setup and diagnostics, initial diagnostic data from three- and six-jet experiments, and the high-level objectives of associated numerical modeling.« less

Observations at Mercury encounter by the plasma science experiment on Mariner 10

NASA Technical Reports Server (NTRS)

Ogilvie, K. W.; Scudder, J. D.; Hartle, R. E.; Siscoe, G. L.; Bridge, H. S.; Lazarus, A. J.; Asbridge, J. R.; Bame, S. J.; Yeates, C. M.

1974-01-01

A fully developed bow shock and magnetosheath were observed near Mercury, providing unambiguous evidence for a strong interaction between Mercury and the solar wind. Inside the sheath there is a distinct region analogous to the magnetosphere or magnetotail of earth, populated by electrons with lower density and higher temperature than the electrons observed in the solar wind or magnetosheath. At the time of encounter, conditions were such that a perpendicular shock was observed on the inbound leg and a parallel shock was observed on the outbound leg of the trajectory, and energetic plasma electron events were detected upstream from the outbound shock crossing. The interaction is most likely not atmospheric, but the data clearly indicate that the obstacle to solar wind flow is magnetic, either intrinsic or induced.

A laser application to nuclear astrophysics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barbui, M.; Hagel, K.; Schmidt, K.

2014-05-09

In the last decade, the availability in high-intensity laser beams capable of producing plasmas with ion energies large enough to induce nuclear reactions has opened new research paths in nuclear physics. We studied the reactions {sup 3}He(d,p){sup 4}He and d(d,n){sup 3}He at temperatures of few keV in a plasma, generated by the interaction of intense ultrafast laser pulses with molecular deuterium or deuterated-methane clusters mixed with {sup 3}He atoms. The yield of 14.7 MeV protons from the {sup 3}He(d,p){sup 4}He reaction was used to extract the astrophysical S factor. Results of the experiment performed at the Center for High Energymore » Density Science at The University of Texas at Austin will be presented.« less

Time domain structures in a colliding magnetic flux rope experiment

NASA Astrophysics Data System (ADS)

Tang, Shawn Wenjie; Gekelman, Walter; Dehaas, Timothy; Vincena, Steve; Pribyl, Patrick

2017-10-01

Electron phase-space holes, regions of positive potential on the scale of the Debye length, have been observed in auroras as well as in laboratory experiments. These potential structures, also known as Time Domain Structures (TDS), are packets of intense electric field spikes that have significant components parallel to the local magnetic field. In an ongoing investigation at UCLA, TDS were observed on the surface of two magnetized flux ropes produced within the Large Plasma Device (LAPD). A barium oxide (BaO) cathode was used to produce an 18 m long magnetized plasma column and a lanthanum hexaboride (LaB6) source was used to create 11 m long kink unstable flux ropes. Using two probes capable of measuring the local electric and magnetic fields, correlation analysis was performed on tens of thousands of these structures and their propagation velocities, probability distribution function and spatial distribution were determined. The TDS became abundant as the flux ropes collided and appear to emanate from the reconnection region in between them. In addition, a preliminary analysis of the permutation entropy and statistical complexity of the data suggests that the TDS signals may be chaotic in nature. Work done at the Basic Plasma Science Facility (BaPSF) at UCLA which is supported by DOE and NSF.

Upgrades toward high-heat flux, liquid lithium plasma-facing components in the NSTX-U

DOE PAGES

Jaworski, M. A.; Brooks, A.; Kaita, R.; ...

2016-08-08

Liquid metal plasma-facing components (PFCs) provide numerous potential advantages over solid-material components. One critique of the approach is the relatively less developed technologies associated with deploying these components in a fusion plasma-experiment. Exploration of the temperature limits of liquid lithium PFCs in a tokamak divertor and the corresponding consequences on core operation are a high priority informing the possibilities for future liquid lithium PFCs. An all-metal NSTX-U is envisioned to make direct comparison between all high-Z wall operation and liquid lithium PFCs in a single device. By executing the all-metal upgrades incrementally, scientific productivity will be maintained while enabling physicsmore » and engineering-science studies to further develop the solid- and liquid-metal components. Six major elements of a flowing liquid-metal divertor system are described and a three-step program for implementing this system is laid out. The upgrade steps involve the first high-Z divertor target upgrade in NSTX-U, pre-filled liquid metal targets and finally, an integrated, flowing liquid metal divertor target. As a result, two example issues are described where the engineering and physics experiments are shown to be closely related in examining the prospects for future liquid metal PFCs.« less

Study of plasma-facing components in the Lithium Tokamak Experiment with the Materials Analysis and Particle Probe

NASA Astrophysics Data System (ADS)

Lucia, M.; Kaita, R.; Majeski, R.; Boyle, D. P.; Granstedt, E. M.; Jacobson, C. M.; Schmitt, J. C.; Allain, J. P.; Bedoya, F.; Gonderman, S.

2013-10-01

The Lithium Tokamak Experiment (LTX) is a spherical torus designed to accommodate solid or liquid lithium as the primary plasma-facing component (PFC). We present initial results from the implementation on LTX of the Materials Analysis and Particle Probe (MAPP) diagnostic, a collaboration among PPPL, Purdue University, and the University of Illinois. MAPP is a compact in vacuo surface science diagnostic, and its operation on LTX will provide the first ever in situ surface measurements of a tokamak first wall environment. With MAPP's analysis techniques, we will study the evolution of the surface chemistry of LTX's first wall as a function of varied temperature and lithium coating. During its 2013 run campaign, LTX will use an electron beam to evaporate lithium onto the first wall from an in-vessel reservoir. We will use two quartz crystal microbalances to estimate thickness of lithium coatings thus applied to the MAPP probe. We have recently installed a set of triple Langmuir probes on LTX, and they will be used to relate LTX edge plasma parameters to MAPP results. We will combine data from MAPP and the triple probes to estimate the local edge recycling coefficient based on desorption of retained hydrogen. This work was supported by U.S. DOE contract DE-AC02-09CH11466.

Emerging trends in X-ray spectroscopic studies of plasma produced by intense laser beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arora, V., E-mail: arora@rrcat.gov.in; Chakera, J. A.; Naik, P. A.

2015-07-31

X-ray line emission from hot dense plasmas, produced by ultra-short high intensity laser systems, has been studied experimentally in recent years for applications in materials science as well as for back-lighter applications. By virtue of the CPA technology, several laser facilities delivering pulses with peak powers in excess of one petawatt (focused intensities > 10{sup 20} W-cm{sup −2}) have either been commissioned across the globe during the last few years or are presently under construction. On the other hand, hard x-ray sources on table top, generating ultra-short duration x-rays at a repetition rate up to 10 kHz, are routinely available formore » time resolved x-ray diffraction studies. In this paper, the recent experiments on x-ray spectroscopic studies of plasma produced by 45 fs, Ti:sapphire laser pulses (focused iintensity > 10{sup 18} W-cm{sup −2}) at RRCAT Indore will be presented.« less

Magnetic Inertial Confinement Fusion (MICF)

NASA Astrophysics Data System (ADS)

Miao, Feng; Zheng, Xianjun; Deng, Baiquan; Liu, Wei; Ou, Wei; Huang, Yi

2016-11-01

Based on the similarity in models of the early Sun and the 3-D common focal region of the micro-pinch in X-pinch experiments, a novel hybrid fusion configuration by continuous focusing of multiple Z-pinched plasma beams on spatially symmetric plasma is proposed. By replacing gravity with Lorentz force with subsequent centripetal spherical pinch, the beam-target fusion reactivity is enhanced in a quasi-spherical converging region, thus achieving MICF. An assessment, presented here, suggests that a practical fusion power source could be achieved using deuterium alone. Plasma instabilities can be suppressed by fast rotation resulting from an asymmetric tangential torsion in the spherical focal region of this configuration. Mathematical equivalence with the Sun allows the development of appropriate equations for the focal region of MICF, which are solved numerically to provide density, temperature and pressure distributions that produce net fusion energy output. An analysis of MICF physics and a preliminary experimental demonstration of a single beam are also carried out. supported by National Natural Science Foundation of China (Nos. 11374217 and 11176020)

Indirect monitoring shot-to-shot shock waves strength reproducibility during pump–probe experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pikuz, T. A., E-mail: tatiana.pikuz@eie.eng.osaka-u.ac.jp; Photon Pioneers Center, Osaka University, Suita, Osaka 565-0871 Japan; Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412

We present an indirect method of estimating the strength of a shock wave, allowing on line monitoring of its reproducibility in each laser shot. This method is based on a shot-to-shot measurement of the X-ray emission from the ablated plasma by a high resolution, spatially resolved focusing spectrometer. An optical pump laser with energy of 1.0 J and pulse duration of ∼660 ps was used to irradiate solid targets or foils with various thicknesses containing Oxygen, Aluminum, Iron, and Tantalum. The high sensitivity and resolving power of the X-ray spectrometer allowed spectra to be obtained on each laser shot and tomore » control fluctuations of the spectral intensity emitted by different plasmas with an accuracy of ∼2%, implying an accuracy in the derived electron plasma temperature of 5%–10% in pump–probe high energy density science experiments. At nano- and sub-nanosecond duration of laser pulse with relatively low laser intensities and ratio Z/A ∼ 0.5, the electron temperature follows T{sub e} ∼ I{sub las}{sup 2/3}. Thus, measurements of the electron plasma temperature allow indirect estimation of the laser flux on the target and control its shot-to-shot fluctuation. Knowing the laser flux intensity and its fluctuation gives us the possibility of monitoring shot-to-shot reproducibility of shock wave strength generation with high accuracy.« less

The spectroscopy and chemical dynamics of microparticles explored using an ultrasonic trap.

PubMed

Mason, N J; Drage, E A; Webb, S M; Dawes, A; McPheat, R; Hayes, G

2008-01-01

Microsized particles play an important role in many diverse areas of science and technology, for example, surface reactions of micron-sized particles play a key role in astrochemistry, plasma reactors and atmospheric chemistry. To date much of our knowledge of such surface chemistry is derived from 'traditional' surface science-based research. However, the large surface area and morphology of surface material commonly used in such surface science techniques may not necessarily mimic that on the surface of micron/nano scale particles. Hence, a new generation of experiments in which the spectroscopy (e.g., albedo) and chemical reactivity of micron-sized particles can be studied directly must be developed. One, as yet underexploited, non-invasive technique is the use of ultrasonic levitation. In this article, we describe the operation of an 'ultrasonic trap' to store and study the physical and chemical properties of microparticles.

Science and technology in the stockpile stewardship program, S & TR reprints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Storm, E

This document reports on these topics: Computer Simulations in Support of National Security; Enhanced Surveillance of Aging Weapons; A New Precision Cutting Tool: The Femtosecond Laser; Superlasers as a Tool of Stockpile Stewardship; Nova Laser Experiments and Stockpile Stewardship; Transforming Explosive Art into Science; Better Flash Radiography Using the FXR; Preserving Nuclear Weapons Information; Site 300Õs New Contained Firing Facility; The Linear Electric Motor: Instability at 1,000 gÕs; A Powerful New Tool to Detect Clandestine Nuclear Tests; High Explosives in Stockpile Surveillance Indicate Constancy; Addressing a Cold War Legacy with a New Way to Produce TATB; JumpinÕ Jupiter! Metallic Hydrogen;more » Keeping the Nuclear Stockpile Safe, Secure, and Reliable; The Multibeam FabryÐPerot Velocimeter: Efficient Measurements of High Velocities; Theory and Modeling in Material Science; The Diamond Anvil Cell; Gamma-Ray Imaging Spectrometry; X-Ray Lasers and High-Density Plasma« less

Study of Plasma Liner Driven Magnetized Target Fusion Via Advanced Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samulyak, Roman V.; Brookhaven National Lab.; Parks, Paul

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

Science on Spacelab. [astronomy, high energy astrophysics, life sciences, and solar, atmospheric and space physics

NASA Technical Reports Server (NTRS)

Schmerling, E. R.

1977-01-01

Spacelab was developed by the European Space Agency for the conduction of scientific and technological experiments in space. Spacelab can be taken into earth orbit by the Space Shuttle and returned to earth after a period of 1-3 weeks. The Spacelab modular system of pallets, pressurized modules, and racks can contain large payloads with high power and telemetry requirements. A working group has defined the 'Atmospheres, Magnetospheres, and Plasmas-in-Space' project. The project objectives include the absolute measurement of solar flux in a number of carefully selected bands at the same time at which atmospheric measurements are made. NASA is committed to the concept that the scientist is to play a key role in its scientific programs.

Simulations of Laboratory Astrophysics Experiments using the CRASH code

NASA Astrophysics Data System (ADS)

Trantham, Matthew; Kuranz, Carolyn; Manuel, Mario; Keiter, Paul; Drake, R. P.

2014-10-01

Computer simulations can assist in the design and analysis of laboratory astrophysics experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport, electron heat conduction and laser ray tracing. This poster/talk will demonstrate some of the experiments the CRASH code has helped design or analyze including: Kelvin-Helmholtz, Rayleigh-Taylor, imploding bubbles, and interacting jet experiments. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via Grant DEFC52-08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0001840, and by the National Laser User Facility Program, Grant Number DE-NA0000850.

Equation of state for two-dimensional dusty plasma liquids and its applications

NASA Astrophysics Data System (ADS)

Feng, Yan

2017-10-01

Laboratory dusty plasma consists of free electrons, free ions, and micro-sized dust particles with thousands of negative elementary charges. Due to their extremely low charge-to-mass ratio, these dust particles are strongly coupled, arranging themselves like atoms in liquids or solids. Due to the shielding effects of electrons and ions, dust particles interact with each other through the Yukawa potential, so that simulations of Yukawa liquids or solids are used to study properties of dusty plasmas. In the past two decades, the properties of liquid 2D dusty plasmas have been widely studied from experiments to theories and simulations. However, from our literature search, we have not found a quantitative and comprehensive study of properties of 2D liquid dusty plasmas over a wide range of plasma conditions. Here, from molecular-dynamics simulations of Yukawa liquids, we have obtained a concise equation of state (EOS) for the 2D liquid dusty plasmas from empirical fitting, which contains three quantities of the internal pressure, the coupling parameter, and the screening parameter. From this EOS, different thermodynamical processes can be directly derived, such as isotherms, isobars and isochores. Also, various physical properties of 2D liquid dusty plasmas, like the bulk modulus of elasticity, can be analytically derived, so that the sound speeds can be obtained. Finally, an analytical expression of the specific heat for 2D liquid dusty plasmas has been achieved. Work supported by the National Natural Science Foundation of China under Grant No. 11505124, the 1000 Youth Talents Plan, and the startup funds from Soochow University.

EDITORIAL: Plasma Surface Interactions for Fusion

NASA Astrophysics Data System (ADS)

2006-05-01

Because plasma-boundary physics encompasses some of the most important unresolved issues for both the International Thermonuclear Experimental Reactor (ITER) project and future fusion power reactors, there is a strong interest in the fusion community for better understanding and characterization of plasma wall interactions. Chemical and physical sputtering cause the erosion of the limiters/divertor plates and vacuum vessel walls (made of C, Be and W, for example) and degrade fusion performance by diluting the fusion fuel and excessively cooling the core, while carbon redeposition could produce long-term in-vessel tritium retention, degrading the superior thermo-mechanical properties of the carbon materials. Mixed plasma-facing materials are proposed, requiring optimization for different power and particle flux characteristics. Knowledge of material properties as well as characteristics of the plasma material interaction are prerequisites for such optimizations. Computational power will soon reach hundreds of teraflops, so that theoretical and plasma science expertise can be matched with new experimental capabilities in order to mount a strong response to these challenges. To begin to address such questions, a Workshop on New Directions for Advanced Computer Simulations and Experiments in Fusion-Related Plasma Surface Interactions for Fusion (PSIF) was held at the Oak Ridge National Laboratory from 21 to 23 March, 2005. The purpose of the workshop was to bring together researchers in fusion related plasma wall interactions in order to address these topics and to identify the most needed and promising directions for study, to exchange opinions on the present depth of knowledge of surface properties for the main fusion-related materials, e.g., C, Be and W, especially for sputtering, reflection, and deuterium (tritium) retention properties. The goal was to suggest the most important next steps needed for such basic computational and experimental work to be facilitated by researchers in fusion, material, and physical sciences. Representatives from many fusion research laboratories attended, and 25 talks were given, the majority of them making up the content of these Workshop proceedings. The presentations of all talks and further information on the Workshop are available at http://www-cfadc.phy.ornl.gov/psif/home.html. The workshop talks dealt with identification of needs from the perspective of integrated fusion simulation and ITER design, recent developments and perspectives on computation of plasma-facing surface properties using the current and expected new generation of computation capability, and with the status of dedicated laboratory experiments which characterize the underlying processes of PSIF. The Workshop summary and conclusions are being published in Nuclear Fusion 45 (2005). We are indebted to Lynda Saddiq and Fay Ownby, secretaries in the Physics Division of ORNL, whose special efforts, devotion, and expertise made possible both the Workshop and these Proceedings. J T Hogan, P S Krstic and F W Meyer Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6372, USA

Electron-ion hybrid instability experiment upgrades to the Auburn Linear Experiment for Instability Studies.

PubMed

DuBois, A M; Arnold, I; Thomas, E; Tejero, E; Amatucci, W E

2013-04-01

The Auburn Linear EXperiment for Instability Studies (ALEXIS) is a laboratory plasma physics experiment used to study spatially inhomogeneous flows in a magnetized cylindrical plasma column that are driven by crossed electric (E) and magnetic (B) fields. ALEXIS was recently upgraded to include a small, secondary plasma source for a new dual source, interpenetrating plasma experiment. Using two plasma sources allows for highly localized electric fields to be made at the boundary of the two plasmas, inducing strong E × B velocity shear in the plasma, which can give rise to a regime of instabilities that have not previously been studied in ALEXIS. The dual plasma configuration makes it possible to have independent control over the velocity shear and the density gradient. This paper discusses the recent addition of the secondary plasma source to ALEXIS, as well as the plasma diagnostics used to measure electric fields and electron densities.

A Physics Exploratory Experiment on Plasma Liner Formation

NASA Technical Reports Server (NTRS)

Thio, Y. C. Francis; Knapp, Charles E.; Kirkpatrick, Ronald C.; Siemon, Richard E.; Turchi, Peter

2002-01-01

Momentum flux for imploding a target plasma in magnetized target fusion (MTF) may be delivered by an array of plasma guns launching plasma jets that would merge to form an imploding plasma shell (liner). In this paper, we examine what would be a worthwhile experiment to do in order to explore the dynamics of merging plasma jets to form a plasma liner as a first step in establishing an experimental database for plasma-jets driven magnetized target fusion (PJETS-MTF). Using past experience in fusion energy research as a model, we envisage a four-phase program to advance the art of PJETS-MTF to fusion breakeven Q is approximately 1). The experiment (PLX (Plasma Liner Physics Exploratory Experiment)) described in this paper serves as Phase I of this four-phase program. The logic underlying the selection of the experimental parameters is presented. The experiment consists of using twelve plasma guns arranged in a circle, launching plasma jets towards the center of a vacuum chamber. The velocity of the plasma jets chosen is 200 km/s, and each jet is to carry a mass of 0.2 mg - 0.4 mg. A candidate plasma accelerator for launching these jets consists of a coaxial plasma gun of the Marshall type.

Observations of single-pass ion cyclotron heating in a trans-sonic flowing plasma

NASA Astrophysics Data System (ADS)

Bering, E. A.; Díaz, F. R. Chang; Squire, J. P.; Glover, T. W.; Carter, M. D.; McCaskill, G. E.; Longmier, B. W.; Brukardt, M. S.; Chancery, W. J.; Jacobson, V. T.

2010-04-01

The VAriable Specific Impulse Magnetoplasma Rocket (VASIMR®) is a high power electric spacecraft propulsion system, capable of Isp/thrust modulation at constant power [F. R. Chang Díaz et al., Proceedings of the 39th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, 8-11 Jan. 2001]. The VASIMR® uses a helicon discharge to generate plasma. This plasma is energized by an rf booster stage that uses left hand polarized slow mode waves launched from the high field side of the ion cyclotron resonance. In the experiments reported in this paper, the booster uses 2-4 MHz waves with up to 50 kW of power. This process is similar to the ion cyclotron heating (ICH) in tokamaks, but in the VASIMR® the ions only pass through the resonance region once. The rapid absorption of ion cyclotron waves has been predicted in recent theoretical studies. These theoretical predictions have been supported with several independent measurements in this paper. The single-pass ICH produced a substantial increase in ion velocity. Pitch angle distribution studies showed that this increase took place in the resonance region where the ion cyclotron frequency was roughly equal to the frequency on the injected rf waves. Downstream of the resonance region the perpendicular velocity boost should be converted to axial flow velocity through the conservation of the first adiabatic invariant as the magnetic field decreases in the exhaust region of the VASIMR®. This paper will review all of the single-pass ICH ion acceleration data obtained using deuterium in the first VASIMR® physics demonstrator machine, the VX-50. During these experiments, the available power to the helicon ionization stage increased from 3 to 20+ kW. The increased plasma density produced increased plasma loading of the ICH coupler. Starting with an initial demonstration of single-pass ion cyclotron acceleration, the experiments demonstrate significant improvements in coupler efficiency and in ion heating efficiency. In deuterium plasma, ≥80% efficient absorption of 20 kW of ICH input power was achieved. No clear evidence for power limiting instabilities in the exhaust beam has been observed.

78 FR 48863 - Fusion Energy Sciences Advisory Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-12

... DEPARTMENT OF ENERGY Fusion Energy Sciences Advisory Committee AGENCY: Office of Science... Services Administration, notice is hereby given that the Fusion Energy Sciences Advisory Committee will be... of Science (DOE), on long-range plans, priorities, and strategies for advancing plasma science...

Low-Frequency Waves in Cold Three-Component Plasmas

NASA Astrophysics Data System (ADS)

Fu, Qiang; Tang, Ying; Zhao, Jinsong; Lu, Jianyong

2016-09-01

The dispersion relation and electromagnetic polarization of the plasma waves are comprehensively studied in cold electron, proton, and heavy charged particle plasmas. Three modes are classified as the fast, intermediate, and slow mode waves according to different phase velocities. When plasmas contain positively-charged particles, the fast and intermediate modes can interact at the small propagating angles, whereas the two modes are separate at the large propagating angles. The near-parallel intermediate and slow waves experience the linear polarization, circular polarization, and linear polarization again, with the increasing wave number. The wave number regime corresponding to the above circular polarization shrinks as the propagating angle increases. Moreover, the fast and intermediate modes cause the reverse change of the electromagnetic polarization at the special wave number. While the heavy particles carry the negative charges, the dispersion relations of the fast and intermediate modes are always separate, being independent of the propagating angles. Furthermore, this study gives new expressions of the three resonance frequencies corresponding to the highly-oblique propagation waves in the general three-component plasmas, and shows the dependence of the resonance frequencies on the propagating angle, the concentration of the heavy particle, and the mass ratio among different kinds of particles. supported by National Natural Science Foundation of China (Nos. 11303099, 41531071 and 41574158), and the Youth Innovation Promotion Association CAS

Bringing Space Science to the Undergraduate Classroom: NASA's USIP Mission

NASA Astrophysics Data System (ADS)

Vassiliadis, D.; Christian, J. A.; Keesee, A. M.; Spencer, E. A.; Gross, J.; Lusk, G. D.

2015-12-01

As part of its participation in NASA's Undergraduate Student Instrument Project (USIP), a team of engineering and physics students at West Virginia University (WVU) built a series of sounding rocket and balloon missions. The first rocket and balloon missions were flown near-simultaneously in a campaign on June 26, 2014 (image). The second sounding rocket mission is scheduled for October 5, 2015. Students took a course on space science in spring 2014, and followup courses in physics and aerospace engineering departments have been developed since then. Guest payloads were flown from students affiliated with WV Wesleyan College, NASA's IV&V Facility, and the University of South Alabama. Students specialized in electrical and aerospace engineering, and space physics topics. They interacted regularly with NASA engineers, presented at telecons, and prepared reports. A number of students decided to pursue internships and/or jobs related to space science and technology. Outreach to the campus and broader community included demos and flight projects. The physics payload includes plasma density and temperature measurements using a Langmuir and a triple probe; plasma frequency measurements using a radio sounder (WVU) and an impedance probe (U.S.A); and a magnetometer (WVWC). The aerospace payload includes an IMU swarm, a GPS experiment (with TEC capability); a cubesat communications module (NASA IV&V), and basic flight dynamics. Acknowledgments: staff members at NASA Wallops Flight Facility, and at the Orbital-ATK Rocket Center, WV.

CICART Center For Integrated Computation And Analysis Of Reconnection And Turbulence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharjee, Amitava

CICART is a partnership between the University of New Hampshire (UNH) and Dartmouth College. CICART addresses two important science needs of the DoE: the basic understanding of magnetic reconnection and turbulence that strongly impacts the performance of fusion plasmas, and the development of new mathematical and computational tools that enable the modeling and control of these phenomena. The principal participants of CICART constitute an interdisciplinary group, drawn from the communities of applied mathematics, astrophysics, computational physics, fluid dynamics, and fusion physics. It is a main premise of CICART that fundamental aspects of magnetic reconnection and turbulence in fusion devices, smaller-scalemore » laboratory experiments, and space and astrophysical plasmas can be viewed from a common perspective, and that progress in understanding in any of these interconnected fields is likely to lead to progress in others. The establishment of CICART has strongly impacted the education and research mission of a new Program in Integrated Applied Mathematics in the College of Engineering and Applied Sciences at UNH by enabling the recruitment of a tenure-track faculty member, supported equally by UNH and CICART, and the establishment of an IBM-UNH Computing Alliance. The proposed areas of research in magnetic reconnection and turbulence in astrophysical, space, and laboratory plasmas include the following topics: (A) Reconnection and secondary instabilities in large high-Lundquist-number plasmas, (B) Particle acceleration in the presence of multiple magnetic islands, (C) Gyrokinetic reconnection: comparison with fluid and particle-in-cell models, (D) Imbalanced turbulence, (E) Ion heating, and (F) Turbulence in laboratory (including fusion-relevant) experiments. These theoretical studies make active use of three high-performance computer simulation codes: (1) The Magnetic Reconnection Code, based on extended two-fluid (or Hall MHD) equations, in an Adaptive Mesh Refinement (AMR) framework, (2) the Particle Simulation Code, a fully electromagnetic 3D Particle-In-Cell (PIC) code that includes a collision operator, and (3) GS2, an Eulerian, electromagnetic, kinetic code that is widely used in the fusion program, and simulates the nonlinear gyrokinetic equations, together with a self-consistent set of Maxwell’s equations.« less

Maternally derived anti-fibroblast growth factor 23 antibody as new tool to reduce phosphorus requirement of chicks.

PubMed

Ren, Zhouzheng; Bütz, Daniel E; Sand, Jordan M; Cook, Mark E

2017-04-01

Novel means to reduce phosphate input into poultry feeds and increase its retention would preserve world phosphate reserves and reduce environmental impact of poultry production. Here we show that a maternally derived antibody to a fibroblast growth factor-23 (FGF-23) peptide (GMNPPPYS) alleviated phosphorus deficiency in chicks fed low non-phytate phosphorus (nPP) diets. White Leghorn laying hens were vaccinated with either an adjuvant control or the synthetic FGF-23 peptide, and chicks with control or anti-FGF-23 maternal antibodies were fed a diet containing either 0.13 or 0.45% nPP (experiment 1), and 0.20 or 0.45% nPP (experiment 2) for 14 d. In both experiments, decreasing nPP from 0.45 to 0.13 or 0.20% decreased BW gain, G:F, excreta phosphorus, plasma phosphate, and plasma FGF-23 at all time periods examined (nPP main effect, P < 0.05). In experiment 1, chicks with maternal anti-FGF-23 antibody had increased tibiotarsi ash (d 14), and decreased excreta phosphate (d 7, 14) and plasma intact parathyroid hormone (d 7) when compared to chicks with control antibody (antibody main effect, P < 0.05). Mortality (d 7 to 14, 1 to 14), posture scores (d 7, 14) and bone lesion scores (d 14) decreased and plasma phosphate (d 14) increased in anti-FGF-23 chicks fed 0.13% nPP, compared to those with control antibody on the same diet (P < 0.05). In experiment 2, chicks with maternal anti-FGF-23 antibody had increased tibiotarsi ash (d 14), and plasma phosphate (d 14) and 1,25(OH)2D3 (d 14) levels, compared to chicks with control antibody (antibody main effect, P < 0.05). BW gain and G:F were increased in chicks with anti-FGF-23 antibody fed 0.20% nPP, compared to control antibody chicks on the same diet, at all time periods examined (P < 0.05). In conclusion, maternally-derived anti-FGF-23 antibody increased phosphorus retention in chicks fed diets containing either 0.13 or 0.20% nPP and thereby, reduced signs of phosphorus deficiency. © 2016 Poultry Science Association Inc.

Dynamic Contraction of the Positive Column of a Self-Sustained Glow Discharge in Molecular Gas Flow

NASA Astrophysics Data System (ADS)

Shneider, Mikhail

2014-10-01

Contraction of the gas discharge, when current contracts from a significant volume of weakly ionized plasma into a thin arc channel, was attracted attention of scientists for more than a century. Studies of the contraction (also called constriction) mechanisms, besides carrying interesting science, are of practical importance, especially when contraction should be prevented. A set of time-dependent two-dimensional equations for the non-equilibrium weakly-ionized nitrogen/ air plasma is formulated. The process is described by a set of time-dependent continuity equations for the electrons, positive and negative ions; gas and vibrational temperature; by taking into account the convective heat and plasma losses by the transverse flux. Transition from the uniform to contracted state was analyzed. It was shown that such transition experiences a hysteresis, and that the critical current of the transition increases when the pressure (gas density) drops. Possible coexistence of the contracted and uniform state of the plasma in the discharge where the current flows along the density gradient of the background gas was discussed. In this talk the problems related to the dynamic contraction of the current channel inside a quasineutral positive column of a self-sustained glow discharge in molecular gas in a rectangular duct with convection cooling will be discussed. Study presented in this talk was stimulated by the fact that there are large number of experiments on the dynamic contraction of a glow discharge in nitrogen and air flows and a many of possible applications. Similar processes play a role in the powerful gas-discharge lasers. In addition, the problem of dynamic contraction in the large volume of non-equilibrium weakly ionized plasma is closely related to the problem of streamer to leader transitions in lightning and blue jets.

Closeout Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dr. Kenneth W. Gentle

2004-11-29

We are conducting a collaborative research program on two tokamaks, HT-7 and EAST (Experimental Advanced Superconducting Tokamak, formerly HT-7U), with the Institute of Plasma Physics of the Chinese Academy of Sciences (CASIPP) located in Hefei, PRC. The work that we planned for this year included conducting transport experiments on HT-7, completing plans for expansion of the HT-7 diagnostic set, and reaching an agreement on how UT-FRC can best participate in experiments on HT-7U. These goals were accomplished as summarized in the next section. Note that the experimental portion of the work is still underway. The experimental campaign for HT-7 beganmore » just a few weeks before this report was compiled.« less

Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacFarlane, Joseph J.; Golovkin, I. E.; Woodruff, P. R.

2009-08-07

This Final Report summarizes work performed under DOE STTR Phase II Grant No. DE-FG02-05ER86258 during the project period from August 2006 to August 2009. The project, “Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments,” was led by Prism Computational Sciences (Madison, WI), and involved collaboration with subcontractors University of Nevada-Reno and Voss Scientific (Albuquerque, NM). In this project, we have: Developed and implemented a multi-dimensional, multi-frequency radiation transport model in the LSP hybrid fluid-PIC (particle-in-cell) code [1,2]. Updated the LSP code to support the use of accurate equation-of-state (EOS) tables generated by Prism’smore » PROPACEOS [3] code to compute more accurate temperatures in high energy density physics (HEDP) plasmas. Updated LSP to support the use of Prism’s multi-frequency opacity tables. Generated equation of state and opacity data for LSP simulations for several materials being used in plasma jet experimental studies. Developed and implemented parallel processing techniques for the radiation physics algorithms in LSP. Benchmarked the new radiation transport and radiation physics algorithms in LSP and compared simulation results with analytic solutions and results from numerical radiation-hydrodynamics calculations. Performed simulations using Prism radiation physics codes to address issues related to radiative cooling and ionization dynamics in plasma jet experiments. Performed simulations to study the effects of radiation transport and radiation losses due to electrode contaminants in plasma jet experiments. Updated the LSP code to generate output using NetCDF to provide a better, more flexible interface to SPECT3D [4] in order to post-process LSP output. Updated the SPECT3D code to better support the post-processing of large-scale 2-D and 3-D datasets generated by simulation codes such as LSP. Updated atomic physics modeling to provide for more comprehensive and accurate atomic databases that feed into the radiation physics modeling (spectral simulations and opacity tables). Developed polarization spectroscopy modeling techniques suitable for diagnosing energetic particle characteristics in HEDP experiments. A description of these items is provided in this report. The above efforts lay the groundwork for utilizing the LSP and SPECT3D codes in providing simulation support for DOE-sponsored HEDP experiments, such as plasma jet and fast ignition physics experiments. We believe that taken together, the LSP and SPECT3D codes have unique capabilities for advancing our understanding of the physics of these HEDP plasmas. Based on conversations early in this project with our DOE program manager, Dr. Francis Thio, our efforts emphasized developing radiation physics and atomic modeling capabilities that can be utilized in the LSP PIC code, and performing radiation physics studies for plasma jets. A relatively minor component focused on the development of methods to diagnose energetic particle characteristics in short-pulse laser experiments related to fast ignition physics. The period of performance for the grant was extended by one year to August 2009 with a one-year no-cost extension, at the request of subcontractor University of Nevada-Reno.« less

Applications of Fusion Energy Sciences Research - Scientific Discoveries and New Technologies Beyond Fusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendt, Amy; Callis, Richard; Efthimion, Philip

Since the 1950s, scientists and engineers in the U.S. and around the world have worked hard to make an elusive goal to be achieved on Earth: harnessing the reaction that fuels the stars, namely fusion. Practical fusion would be a source of energy that is unlimited, safe, environmentally benign, available to all nations and not dependent on climate or the whims of the weather. Significant resources, most notably from the U.S. Department of Energy (DOE) Office of Fusion Energy Sciences (FES), have been devoted to pursuing that dream, and significant progress is being made in turning it into a reality.more » However, that is only part of the story. The process of creating a fusion-based energy supply on Earth has led to technological and scientific achievements of far-reaching impact that touch every aspect of our lives. Those largely unanticipated advances, spanning a wide variety of fields in science and technology, are the focus of this report. There are many synergies between research in plasma physics (the study of charged particles and fluids interacting with self-consistent electric and magnetic fields), high-energy physics, and condensed matter physics dating back many decades. For instance, the formulation of a mathematical theory of solitons, solitary waves which are seen in everything from plasmas to water waves to Bose-Einstein Condensates, has led to an equal span of applications, including the fields of optics, fluid mechanics and biophysics. Another example, the development of a precise criterion for transition to chaos in Hamiltonian systems, has offered insights into a range of phenomena including planetary orbits, two-person games and changes in the weather. Seven distinct areas of fusion energy sciences were identified and reviewed which have had a recent impact on fields of science, technology and engineering not directly associated with fusion energy: Basic plasma science; Low temperature plasmas; Space and astrophysical plasmas; High energy density laboratory plasmas and inertial fusion energy; Particle accelerator technology; Fusion nuclear science; and Magnetically confined plasmas. Individual sections within the report summarize applications associated with each of these areas. These sections were also informed by a survey that went out to the community, and the subcommittee wishes to thank those who responded, as well as to the national labs and universities that contributed photographs.« less

Fusion energy science: Clean, safe, and abundant energy through innovative science and technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Fusion energy science combines the study of the behavior of plasmas--the state of matter that forms 99% of the visible universe--with a vision of using fusion--the energy source of the stars--to create an affordable, plentiful, and environmentally benign energy source for humankind. The dual nature of fusion energy science provides an unfolding panorama of exciting intellectual challenge and a promise of an attractive energy source for generations to come. The goal of this report is a comprehensive understanding of plasma behavior leading to an affordable and attractive fusion energy source.

Database and Related Activities in Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murakami, Izumi; Kato, Daiji; Kato, Masatoshi

2011-05-11

We have constructed and made available atomic and molecular (AM) numerical databases on collision processes such as electron-impact excitation and ionization, recombination and charge transfer of atoms and molecules relevant for plasma physics, fusion research, astrophysics, applied-science plasma, and other related areas. The retrievable data is freely accessible via the internet. We also work on atomic data evaluation and constructing collisional-radiative models for spectroscopic plasma diagnostics. Recently we have worked on Fe ions and W ions theoretically and experimentally. The atomic data and collisional-radiative models for these ions are examined and applied to laboratory plasmas. A visible M1 transition ofmore » W{sup 26+} ion is identified at 389.41 nm by EBIT experiments and theoretical calculations. We have small non-retrievable databases in addition to our main database. Recently we evaluated photo-absorption cross sections for 9 atoms and 23 molecules and we present them as a new database. We established a new association ''Forum of Atomic and Molecular Data and Their Applications'' to exchange information among AM data producers, data providers and data users in Japan and we hope this will help to encourage AM data activities in Japan.« less

Database and Related Activities in Japan

NASA Astrophysics Data System (ADS)

Murakami, Izumi; Kato, Daiji; Kato, Masatoshi; Sakaue, Hiroyuki A.; Kato, Takako; Ding, Xiaobin; Morita, Shigeru; Kitajima, Masashi; Koike, Fumihiro; Nakamura, Nobuyuki; Sakamoto, Naoki; Sasaki, Akira; Skobelev, Igor; Tsuchida, Hidetsugu; Ulantsev, Artemiy; Watanabe, Tetsuya; Yamamoto, Norimasa

2011-05-01

We have constructed and made available atomic and molecular (AM) numerical databases on collision processes such as electron-impact excitation and ionization, recombination and charge transfer of atoms and molecules relevant for plasma physics, fusion research, astrophysics, applied-science plasma, and other related areas. The retrievable data is freely accessible via the internet. We also work on atomic data evaluation and constructing collisional-radiative models for spectroscopic plasma diagnostics. Recently we have worked on Fe ions and W ions theoretically and experimentally. The atomic data and collisional-radiative models for these ions are examined and applied to laboratory plasmas. A visible M1 transition of W26+ ion is identified at 389.41 nm by EBIT experiments and theoretical calculations. We have small non-retrievable databases in addition to our main database. Recently we evaluated photo-absorption cross sections for 9 atoms and 23 molecules and we present them as a new database. We established a new association "Forum of Atomic and Molecular Data and Their Applications" to exchange information among AM data producers, data providers and data users in Japan and we hope this will help to encourage AM data activities in Japan.

Stellarator Research Opportunities: A Report of the National Stellarator Coordinating Committee

DOE PAGES

Gates, David A.; Anderson, David; Anderson, S.; ...

2018-02-19

This paper is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generatemore » a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in “Fusion Energy Sciences: A Ten-Year Perspective (2015–2025)” [1]. The natural disruption immunity of the stellarator directly addresses “Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices” an area of critical importance for the US fusion energy sciences enterprise over the next decade. Another critical area of research “Strengthening our partnerships with international research facilities,” is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. Finally, this report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; “Burning Plasma Science: Foundations—Next-generation research capabilities”, and “Burning Plasma Science: Long pulse—Sustainment of Long-Pulse Plasma Equilibria” are proposed.« less

Stellarator Research Opportunities: A Report of the National Stellarator Coordinating Committee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gates, David A.; Anderson, David; Anderson, S.

This paper is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generatemore » a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in “Fusion Energy Sciences: A Ten-Year Perspective (2015–2025)” [1]. The natural disruption immunity of the stellarator directly addresses “Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices” an area of critical importance for the US fusion energy sciences enterprise over the next decade. Another critical area of research “Strengthening our partnerships with international research facilities,” is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. Finally, this report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; “Burning Plasma Science: Foundations—Next-generation research capabilities”, and “Burning Plasma Science: Long pulse—Sustainment of Long-Pulse Plasma Equilibria” are proposed.« less

Stellarator Research Opportunities: A Report of the National Stellarator Coordinating Committee

NASA Astrophysics Data System (ADS)

Gates, D. A.; Anderson, D.; Anderson, S.; Zarnstorff, M.; Spong, D. A.; Weitzner, H.; Neilson, G. H.; Ruzic, D.; Andruczyk, D.; Harris, J. H.; Mynick, H.; Hegna, C. C.; Schmitz, O.; Talmadge, J. N.; Curreli, D.; Maurer, D.; Boozer, A. H.; Knowlton, S.; Allain, J. P.; Ennis, D.; Wurden, G.; Reiman, A.; Lore, J. D.; Landreman, M.; Freidberg, J. P.; Hudson, S. R.; Porkolab, M.; Demers, D.; Terry, J.; Edlund, E.; Lazerson, S. A.; Pablant, N.; Fonck, R.; Volpe, F.; Canik, J.; Granetz, R.; Ware, A.; Hanson, J. D.; Kumar, S.; Deng, C.; Likin, K.; Cerfon, A.; Ram, A.; Hassam, A.; Prager, S.; Paz-Soldan, C.; Pueschel, M. J.; Joseph, I.; Glasser, A. H.

2018-02-01

This document is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generate a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in "Fusion Energy Sciences: A Ten-Year Perspective (2015-2025)" [1]. The natural disruption immunity of the stellarator directly addresses "Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices" an area of critical importance for the US fusion energy sciences enterprise over the next decade. Another critical area of research "Strengthening our partnerships with international research facilities," is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. This report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; "Burning Plasma Science: Foundations - Next-generation research capabilities", and "Burning Plasma Science: Long pulse - Sustainment of Long-Pulse Plasma Equilibria" are proposed.

Stellarator Research Opportunities: A report of the National Stellarator Coordinating Committee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gates, David A.; Anderson, David

This document is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generatemore » a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in “Fusion Energy Sciences: A Ten-Year Perspective (2015-2025)” [2]. The natural disruption immunity of the stellarator directly addresses “Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices” an area of critical importance for the U.S. fusion energy sciences enterprise over the next decade. Another critical area of research “Strengthening our partnerships with international research facilities,” is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. This report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; “Burning Plasma Science: Foundations - Next-generation research capabilities”, and “Burning Plasma Science: Long pulse - Sustainment of Long-Pulse Plasma Equilibria” are proposed.« less

The 2017 Plasma Roadmap: Low temperature plasma science and technology

NASA Astrophysics Data System (ADS)

Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; Bruggeman, P. J.; Cappelli, M.; Colombo, V.; Czarnetzki, U.; Ebert, U.; Eden, J. G.; Favia, P.; Graves, D. B.; Hamaguchi, S.; Hieftje, G.; Hori, M.; Kaganovich, I. D.; Kortshagen, U.; Kushner, M. J.; Mason, N. J.; Mazouffre, S.; Mededovic Thagard, S.; Metelmann, H.-R.; Mizuno, A.; Moreau, E.; Murphy, A. B.; Niemira, B. A.; Oehrlein, G. S.; Petrovic, Z. Lj; Pitchford, L. C.; Pu, Y.-K.; Rauf, S.; Sakai, O.; Samukawa, S.; Starikovskaia, S.; Tennyson, J.; Terashima, K.; Turner, M. M.; van de Sanden, M. C. M.; Vardelle, A.

2017-08-01

Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The current state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.

Micro- to macroscale perspectives on space plasmas

NASA Technical Reports Server (NTRS)

Eastman, Timothy E.

1993-01-01

The Earth's magnetosphere is the most accessible of natural collisionless plasma environments; an astrophysical plasma 'laboratory'. Magnetospheric physics has been in an exploration phase since its origin 35 years ago but new coordinated, multipoint observations, theory, modeling, and simulations are moving this highly interdisciplinary field of plasma science into a new phase of synthesis and understanding. Plasma systems are ones in which binary collisions are relatively negligible and collective behavior beyond the microscale emerges. Most readily accessible natural plasma systems are collisional and nearest-neighbor classical interactions compete with longer-range plasma effects. Except for stars, most space plasmas are collisionless, however, and the effects of electrodynamic coupling dominate. Basic physical processes in such collisionless plasmas occur at micro-, meso-, and macroscales that are not merely reducible to each other in certain crucial ways as illustrated for the global coupling of the Earth's magnetosphere and for the nonlinear dynamics of charged particle motion in the magnetotail. Such global coupling and coherence makes the geospace environment, the domain of solar-terrestrial science, the most highly coupled of all physical geospheres.

Applying a laser-induced incandescence (LII) diagnostic to monitor nanoparticle synthesis in an atmospheric plasma, in situ

NASA Astrophysics Data System (ADS)

Yatom, Shurik; Mitrani, James; Yeh, Yao-Wen; Shneider, Mikhail; Stratton, Brentley; Raitses, Yevgeny

2016-09-01

A DC arc discharge with a consumed graphite anode is commonly used for synthesis of carbon nanoparticles, including carbon nanotubes (CNTs) and graphene flakes. The graphite electrode is physically vaporized by high currents (20-60 A) in a buffer gas at 100-600 torr, leading to nanoparticle synthesis in a low temperature (>1 eV), plasma. Utilizing arc plasma synthesis technique has resulted in the synthesis of higher quality nanomaterials. However, the formation of nanoparticles in arc discharge plasmas is poorly understood. A particularly interesting question is where in the arc the nanoparticles nucleate and grow. In our current work we show the results of studying the formation of carbon nanotubes in an arc discharge, in situ, using laser-induced incandescence (LII). The results of LII are discussed in combination with ex situ measurements of the synthesized nanoparticles and modeling, to provide an insight into the physics behind nanoparticle synthesis in plasma. This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

Plasmas for medicine

NASA Astrophysics Data System (ADS)

von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.

2013-09-01

Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous economic potential. This ambivalent situation fundamentally requires a responsible use of plasma sources, which are specifically designated for biomedical applications. To enable physicians as well as life scientists to decide whether a given plasma source is really suitable for medical applications or biological experiments, a meaningful and mandatory spectrum of indicators has to be compiled to allow for a basic estimation of the potential of this plasma source.

The Basic Plasma Science Facility: a platform for studying plasma processes relevant to space and astrophysical settings

NASA Astrophysics Data System (ADS)

Carter, T. A.

2017-10-01

The Basic Plasma Science Facility at UCLA is a national user facility for studies of fundamental processes in magnetized plasmas. The centerpiece is the Large Plasma Device, a 20 m, magnetized linear plasma device. Two hot cathode plasma sources are available. A Barium Oxide coated cathode produces plasmas with n 1012 cm-3, Te 5 eV, Ti < 1 eV with magnetic field from 400G-2kG. This low- β plasma has been used to study fundamental processes, including: dispersion and damping of kinetic and inertial Alfvén waves, flux ropes and magnetic reconnection, three-wave interactions and parametric instabilities of Alfvén waves, turbulence and transport, and interactions of energetic ions and electrons with plasma waves. A new Lanthanum Hexaboride (LaB6) cathode is now available which produces significantly higher densities and temperatures: n < 5 ×1013 cm-3, Te 12 eV, Ti 6 eV. This higher pressure plasma source enabled the observation of laser-driven collisionless magnetized shocks and, with lowered magnetic field, provides magnetized plasmas with β approaching or possibly exceeding unity. This opens up opportunities for investigating processes relevant to the solar wind and astrophysical plasmas. BaPSF is jointly supported by US DOE and NSF.

EDITORIAL: Laser and plasma accelerators Laser and plasma accelerators

NASA Astrophysics Data System (ADS)

Bingham, Robert

2009-02-01

This special issue on laser and plasma accelerators illustrates the rapid advancement and diverse applications of laser and plasma accelerators. Plasma is an attractive medium for particle acceleration because of the high electric field it can sustain, with studies of acceleration processes remaining one of the most important areas of research in both laboratory and astrophysical plasmas. The rapid advance in laser and accelerator technology has led to the development of terawatt and petawatt laser systems with ultra-high intensities and short sub-picosecond pulses, which are used to generate wakefields in plasma. Recent successes include the demonstration by several groups in 2004 of quasi-monoenergetic electron beams by wakefields in the bubble regime with the GeV energy barrier being reached in 2006, and the energy doubling of the SLAC high-energy electron beam from 42 to 85 GeV. The electron beams generated by the laser plasma driven wakefields have good spatial quality with energies ranging from MeV to GeV. A unique feature is that they are ultra-short bunches with simulations showing that they can be as short as a few femtoseconds with low-energy spread, making these beams ideal for a variety of applications ranging from novel high-brightness radiation sources for medicine, material science and ultrafast time-resolved radiobiology or chemistry. Laser driven ion acceleration experiments have also made significant advances over the last few years with applications in laser fusion, nuclear physics and medicine. Attention is focused on the possibility of producing quasi-mono-energetic ions with energies ranging from hundreds of MeV to GeV per nucleon. New acceleration mechanisms are being studied, including ion acceleration from ultra-thin foils and direct laser acceleration. The application of wakefields or beat waves in other areas of science such as astrophysics and particle physics is beginning to take off, such as the study of cosmic accelerators considered by Chen et al where the driver, instead of being a laser, is a whistler wave known as the magnetowave plasma accelerator. The application to electron--positron plasmas that are found around pulsars is studied in the paper by Shukla, and to muon acceleration by Peano et al. Electron wakefield experiments are now concentrating on control and optimisation of high-quality beams that can be used as drivers for novel radiation sources. Studies by Thomas et al show that filamentation has a deleterious effect on the production of high quality mono-energetic electron beams and is caused by non-optimal choice of focusing geometry and/or electron density. It is crucial to match the focusing with the right plasma parameters and new types of plasma channels are being developed, such as the magnetically controlled plasma waveguide reported by Froula et al. The magnetic field provides a pressure profile shaping the channel to match the guiding conditions of the incident laser, resulting in predicted electron energies of 3GeV. In the forced laser-wakefield experiment Fang et al show that pump depletion reduces or inhibits the acceleration of electrons. One of the earlier laser acceleration concepts known as the beat wave may be revived due to the work by Kalmykov et al who report on all-optical control of nonlinear focusing of laser beams, allowing for stable propagation over several Rayleigh lengths with pre-injected electrons accelerated beyond 100 MeV. With the increasing number of petawatt lasers, attention is being focused on different acceleration regimes such as stochastic acceleration by counterpropagating laser pulses, the relativistic mirror, or the snow-plough effect leading to single-step acceleration reported by Mendonca. During wakefield acceleration the leading edge of the pulse undergoes frequency downshifting and head erosion as the laser energy is transferred to the wake while the trailing edge of the laser pulse undergoes frequency up-shift. This is commonly known as photon deceleration and acceleration and is the result of a modulational instability. Simulations reported by Trines et al using a photon-in-cell code or wave kinetic code agree extremely well with experimental observation. Ion acceleration is actively studied; for example the papers by Robinson, Macchi, Marita and Tripathi all discuss different types of acceleration mechanisms from direct laser acceleration, Coulombic explosion and double layers. Ion acceleration is an exciting development that may have great promise in oncology. The surprising application is in muon acceleration, demonstrated by Peano et al who show that counterpropagating laser beams with variable frequencies drive a beat structure with variable phase velocity, leading to particle trapping and acceleration with possible application to a future muon collider and neutrino factory. Laser and plasma accelerators remain one of the exciting areas of plasma physics with applications in many areas of science ranging from laser fusion, novel high-brightness radiation sources, particle physics and medicine. The guest editor would like to thank all authors and referees for their invaluable contributions to this special issue.

THOR contribution to space weather science

NASA Astrophysics Data System (ADS)

Vaivads, A.; Opgenoorth, H. J.; Retino, A.; Khotyaintsev, Y. V.; Soucek, J.; Valentini, F.; Escoubet, C. P.; Chen, C. H. K.; Vainio, R. O.; Fazakerley, A. N.; Lavraud, B.; Narita, Y.; Marcucci, M. F.; Kucharek, H.; Bale, S. D.; Moore, T. E.; Kistler, L. M.; Samara, M.

2016-12-01

Turbulence Heating ObserveR - THOR is a mission proposal to study energy dissipation and particle acceleration in turbulent space plasma. THOR will focus on turbulent plasma in pristine solar wind, bow shock and magnetosheath. The orbit of THOR is tuned to spend long times in those regions allowing THOR to obtain high resolution data sets that can be used also for space weather science. Here we will discuss the space weather science questions that can be addressed and significantly advanced using THOR. Link to THOR: http://thor.irfu.se.

Lunar plasma measurement by MAP-PACE onboard KAGUYA (SELENE)

NASA Astrophysics Data System (ADS)

Saito, Yoshifumi

Low energy charged particles around the Moon were vigorously observed by Moon orbiting satellites and plasma instrumentation placed on the lunar surface in 1960s and 1970s. Though there were some satellites that explored the Moon afterwards, most of them were dedicated to the global mapping of the lunar surface. KAGUYA(SELENE) is a Japanese lunar orbiter that studies the origin and evolution of the Moon by means of global mapping of element abundances, mineralogical composition, and surface geographical mapping from 100km altitude. KAGUYA was successfully launched on 14 September 2007 by HIIA launch vehicle from Tanegashima Space Center in Japan. KAGUYA was inserted into a circular lunar polar orbit of 100km altitude and started continuous observation in mid-December 2007. One of the fourteen science instruments MAP-PACE (MAgnetic field and Plasma experiment - Plasma energy Angle and Composition Experiment) was developed for the comprehensive three-dimensional plasma measurement around the Moon. MAP-PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measure the distribution function of low energy electrons below 15keV. IMA and IEA measure the distribution function of low energy ions below 28keV/q. IMA has an ability to discriminate the ion mass with high mass resolution. PACE sensors have been measuring solar wind, plasmas in the wake region of the Moon and plasmas in the Earth's magnetosphere. ESA sensors have discovered electron heating over magnetic anomalies on the lunar surface. ESA sensors have also observed electrons accelerated from the lunar surface in the wake region. PACE ion sensors have discovered new features of low energy ions around the Moon. IMA has discovered the existence of alkali ions that are originated from the lunar surface or lunar atmosphere and are picked up by the solar wind. IEA and IMA sensors discovered solar wind reflection by the Moon. PACE ion sensors also discovered that ions are rarefied over the magnetic anomaly on the lunar surface while electrons are heated. MAP-PACE has been revealing unexpectedly active plasma environment around the Moon.

Laser interferometry of radiation driven gas jets

NASA Astrophysics Data System (ADS)

Swanson, Kyle James; Ivanov, Vladimir; Mancini, Roberto; Mayes, Daniel C.

2017-06-01

In a series of experiments performed at the 1MA Zebra pulsed power accelerator of the Nevada Terawatt Facility nitrogen gas jets were driven with the broadband x-ray flux produced during the collapse of a wire-array z-pinch implosion. The wire arrays were comprised of 4 and 8, 10μm-thick gold wires and 17μm-thick nickel wires, 2cm and 3cm tall, and 0.3cm in diameter. They radiated 12kJ to 16kJ of x-ray energy, most of it in soft x-ray photons of less than 1keV of energy, in a time interval of 30ns. This x-ray flux was used to drive a nitrogen gas jet located at 0.8cm from the axis of the z-pinch radiation source and produced with a supersonic nozzle. The x-ray flux ionizes the nitrogen gas thus turning it into a photoionized plasma. We used laser interferometry to probe the ionization of the plasma. To this end, a Mach-Zehnder interferometer at the wavelength of 266 nm was set up to extract the atom number density profile of the gas jet just before the Zebra shot, and air-wedge interferometers at 266 and 532 nm were used to determine the electron number density of the plasma right during the Zebra shot. The ratio of electron to atom number densities gives the distribution of average ionization state of the plasma. A python code was developed to perform the image data processing, extract phase shift spatial maps, and obtain the atom and electron number densities via Abel inversion. Preliminary results from the experiment are promising and do show that a plasma has been created in the gas jet driven by the x-ray flux, thus demonstrating the feasibility of a new experimental platform to study photoionized plasmas in the laboratory. These plasmas are found in astrophysical scenarios including x-ray binaries, active galactic nuclei, and the accretion disks surrounding black holes1. This work was sponsored in part by DOE Office of Science Grant DE-SC0014451.1R. C. Mancini et al, Phys. Plasmas 16, 041001 (2009)

Dust charging and levitating in a sheath of plasma containing energetic particles

NASA Astrophysics Data System (ADS)

Ou, Jing; Zhao, Xiao-Yun; Lin, Bin-Bin

2018-02-01

Not Available Project supported by the National Natural Science Foundation of China (Grant No. 11475223), the National Magnetic Confinement Fusion Science Program of China (Grant No. 2015GB101003), and the JSPS-NRF-NSFC A3 Foresight Program in the field of Plasma Physics (Grant Nos. 11261140328 and 2012K2A2A6000443).

Galileo radio science investigations

NASA Technical Reports Server (NTRS)

Howard, H. T.; Eshleman, V. R.; Hinson, D. P.; Kliore, A. J.; Lindal, G. F.; Woo, R.; Bird, M. K.; Volland, H.; Edenhoffer, P.; Paetzold, M.

1992-01-01

Galileo radio-propagation experiments are based on measurements of absolute and differential propagation time delay, differential phase delay, Doppler shift, signal strength, and polarization. These measurements can be used to study: the atmospheric and ionospheric structure, constituents, and dynamics of Jupiter; the magnetic field of Jupiter; the diameter of Io, its ionospheric structure, and the distribution of plasma in the Io torus; the diameters of the other Galilean satellites, certain properties of their surfaces, and possibly their atmospheres and ionospheres; and the plasma dynamics and magnetic field of the solar corona. The spacecraft system provides linear rather than circular polarization on the S-band downlink signal, the capability to receive X-band uplink signals, and a differential downlink ranging mode. A highly-stable, dual-frequency, spacecraft radio system is developed that is suitable for simultaneous measurements of all the parameters normally attributed to radio waves.

Deuterium sputtering of Li and Li-O films

NASA Astrophysics Data System (ADS)

Nelson, Andrew; Buzi, Luxherta; Kaita, Robert; Koel, Bruce

2017-10-01

Lithium wall coatings have been shown to enhance the operational plasma performance of many fusion devices, including NSTX and other tokamaks, by reducing the global wall recycling coefficient. However, pure lithium surfaces are extremely difficult to maintain in experimental fusion devices due to both inevitable oxidation and codeposition from sputtering of hot plasma facing components. Sputtering of thin lithium and lithium oxide films on a molybdenum target by energetic deuterium ion bombardment was studied in laboratory experiments conducted in a surface science apparatus. A Colutron ion source was used to produce a monoenergetic, mass-selected ion beam. Measurements were made under ultrahigh vacuum conditions as a function of surface temperature (90-520 K) using x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and temperature programmed desorption (TPD). Results are compared with computer simulations conducted on a temperature-dependent data-calibrated (TRIM) model.

Plasma Jet Interaction with Thomson Scattering Probe Laser

NASA Astrophysics Data System (ADS)

Byvank, Tom; Banasek, Jacob; Potter, William; Kusse, Bruce

2016-10-01

Thomson scattering systems can diagnose plasma temperatures and velocities. When probing a plasma jet with the Thomson scattering laser, we observe a laser-plasma interaction that inputs energy into the plasma jet. The absorbed energy causes a bubble of low density ( 5*1017 cm-2) in the jet (unperturbed 1018 cm-2). A pulsed power machine (1 MA peak current, 100 ns rise time) with a radial foil (15 μm thick Al) configuration generates the plasma jet. We compare the effects of using 10 J and 1 J laser energies, for which the 10 J laser is a larger perturbation. We discuss how the interaction affects the Thomson scattering temperature and velocity measurements. Work supported by National Nuclear Security Administration (NNSA) Stewardship Sciences Academic Programs under Department of Energy (DOE) Cooperative Agreement DE-NA0001836 and National Science Foundation (NSF) Grant PHY-1102471.

Effects of parturition and feed restriction on concentrations and distribution of the insulin-like growth factor-binding proteins in plasma and cerebrospinal fluid of dairy cows.

PubMed

Laeger, T; Wirthgen, E; Piechotta, M; Metzger, F; Metges, C C; Kuhla, B; Hoeflich, A

2014-05-01

Hormones and metabolites act as satiety signals in the brain and play an important role in the control of feed intake (FI). These signals can reach the hypothalamus and brainstem, 2 major centers of FI regulation, via the blood stream or the cerebrospinal fluid (CSF). During the early lactation period of high-yielding dairy cows, the increase of FI is often insufficient. Recently, it has been demonstrated that insulin-like growth factors (IGF) may control FI. Thus, we asked in the present study if IGF-binding proteins (IGFBP) are regulated during the periparturient period and in response to feed restriction and therefore might affect FI as well. In addition, we specifically addressed conditional distribution of IGFBP in plasma and CSF. In one experiment, 10 multiparous German Holstein dairy cows were fed ad libitum and samples of CSF and plasma were obtained before morning feeding on d -20, -10, +1, +10, +20, and +40 relative to calving. In a second experiment, 7 cows in second mid-lactation were sampled for CSF and plasma after ad libitum feeding and again after feeding 50% of the previous ad libitum intake for 4 d. Intact IGFBP-2, IGFBP-3, and IGFBP-4 were detected in plasma by quantitative Western ligand blot analysis. In CSF, we were able to predominantly identify intact IGFBP-2 and a specific IGFBP-2 fragment containing detectable binding affinities for biotinylated IGF-II. Whereas plasma concentrations of IGFBP-2 and IGFBP-4 increased during the periparturient period, IGFBP-3 was unaffected over time. In CSF, concentrations of IGFBP-2, both intact and fragmented, were not affected during the periparturient period. Plasma IGF-I continuously decreased until calving but remained at a lower concentration in early lactation than in late pregnancy. Food restriction did not affect concentrations of IGF components present in plasma or CSF. We could show that the IGFBP profiles in plasma and CSF are clearly distinct and that changes in IGFBP in plasma do not simply correspond in the brain. We thus assume independent control of IGFBP distribution between plasma and CSF. Due to the known anorexic effect of IGF-I, elevated plasma concentrations of IGFBP-2 and IGFBP-4 during the postpartum period in conjunction with reduced plasma IGF-I concentrations may be interpreted as an endocrine response against negative energy balance in early lactation in dairy cows. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The Citizen CATE Experiment for the 2017 Total Solar Eclipse

NASA Astrophysics Data System (ADS)

Penn, M. J.

2015-12-01

The path of the total solar eclipse of 21 August 2017 passes over about 10 million homes in the USA. Tens of millions more people will travel to the path of totality to view the eclipse first-hand. Using TV and the internet broadcasts, hundreds of millions of people will watch the eclipse, making the event the most viewed astronomical event in the history of mankind. The Citizen Continental-America Telescopic Eclipse (CATE) Experiment for 2017 is being developed at the National Solar Observatory in partnership with universities, schools, astronomy clubs, and corporations. The CATE experiment will use more than 60 identical telescopes equipped with digital cameras positioned from Oregon to South Carolina to image the solar corona. The project will then splice these images together to show the corona during a 90-minute period, revealing for the first time the plasma dynamics of the inner solar corona. The goals for the highly leveraged CATE experiment are diverse and range from providing an authentic STEM research experience for students and lifelong learners, to making state-of-the-art solar coronal observations of the plasma dynamics of coronal polar plumes, to increasing the US scientific literacy. A key goal of this experiment is to donate the telescope and camera system to the volunteer who collects data with it during the total eclipse. The instrument will be then used for a variety of follow-up citizen science projects in astronomy, ranging from solar to cometary to variable star observations. For this reason no government funding is being sought for the equipment costs, but rather private and corporate sources are being developed. The data collected for the 2017 eclipse will be freely available to the scientific, education and amateur astronomy communities. Crowd sourcing the data collection is an essential part of this project, as there are not enough solar physicists in this country to collect these observations. Finally, each site is expected to collect about 10 Gbytes of science data and 10 Gbytes of calibration data, resulting in 1.2 Tbytes of data for the project.

ESA's space science programme

NASA Astrophysics Data System (ADS)

Volonte, S.

2018-04-01

The Space Science Programme of ESA encompasses three broad areas of investigation, namely solar system science (the Sun, the planets and space plasmas), fundamental physics and space astronomy and astrophysics.

TOPICAL REVIEW: Advances and challenges in computational plasma science

NASA Astrophysics Data System (ADS)

Tang, W. M.; Chan, V. S.

2005-02-01

Scientific simulation, which provides a natural bridge between theory and experiment, is an essential tool for understanding complex plasma behaviour. 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. The advances in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics have produced increasingly good agreement between experimental observations and computational modelling. This was enabled by two key factors: (a) innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales and (b) access to powerful new computational resources. Excellent progress has been made in developing codes for which computer run-time and problem-size scale well with the number of processors on massively parallel processors (MPPs). Examples include the effective usage of the full power of multi-teraflop (multi-trillion floating point computations per second) MPPs to produce three-dimensional, general geometry, nonlinear particle simulations that have accelerated advances in understanding the nature of turbulence self-regulation by zonal flows. These calculations, which typically utilized billions of particles for thousands of time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In looking towards the future, the current results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. This should produce the scientific excitement which will help to (a) stimulate enhanced cross-cutting collaborations with other fields and (b) attract the bright young talent needed for the future health of the field of plasma science.

Advances and challenges in computational plasma science

NASA Astrophysics Data System (ADS)

Tang, W. M.

2005-02-01

Scientific simulation, which provides a natural bridge between theory and experiment, is an essential tool for understanding complex plasma behaviour. 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. The advances in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics have produced increasingly good agreement between experimental observations and computational modelling. This was enabled by two key factors: (a) innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales and (b) access to powerful new computational resources. Excellent progress has been made in developing codes for which computer run-time and problem-size scale well with the number of processors on massively parallel processors (MPPs). Examples include the effective usage of the full power of multi-teraflop (multi-trillion floating point computations per second) MPPs to produce three-dimensional, general geometry, nonlinear particle simulations that have accelerated advances in understanding the nature of turbulence self-regulation by zonal flows. These calculations, which typically utilized billions of particles for thousands of time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In looking towards the future, the current results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. This should produce the scientific excitement which will help to (a) stimulate enhanced cross-cutting collaborations with other fields and (b) attract the bright young talent needed for the future health of the field of plasma science.

Venus Express - the First European Mission to Venus

NASA Astrophysics Data System (ADS)

Titov, D. V.; Svedhem, H.; Venus Express Team

2005-08-01

The ESA Venus Express mission is based on reuse of the Mars Express spacecraft and the payload available from the Mars Express and Rosetta missions. In less than 3 years the spacecraft was rebuilt with modifications to cope with harsh environment at Venus and fully tested. The Venus Express will be launched in the end of October 2005 from Baykonur (Kazakhstan) by the Russian Sojuz-Fregat rocket. In the beginning of April 2006 the spacecraft will be inserted in a polar orbit around Venus with pericenter of 250 km and apocentre of 66,000 km and a period of 24 hours. The planned mission duration is two Venus sidereal days ( 500 Earth days) with possibility to extend the mission for two more Venus days. The Venus Express aims at a global investigation of the Venus atmosphere and the plasma environment, and addresses some important aspects of the surface physics. The science goals comprise investigation of the atmospheric structure and composition, cloud layer and hazes, global circulation and radiative balance, plasma and escape processes, and surface properties. These topics will be addressed by seven instruments onboard the satellite: Analyzer of Space Plasma (ASPERA), Magnetometer (MAG), IR Fourier spectrometer (PFS), spectrometer for solar and stellar occultation (SPICAV), radio science experiment (VeRa), visible and IR imaging spectrometer (VIRTIS), and Venus Monitoring Camera (VMC). Scientific operations will include observations in pericentre, off-pericentre and apocentre sessions, limb scans, solar and stellar occultation, radio occultation, bi-static radar, and solar corona sounding.

Recent Progress on Spherical Torus Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ono, Masayuki; Kaita, Robert

2014-01-01

The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A = R0/a) reduced to A ~ 1.5, well below the normal tokamak operating range of A ≥ 2.5. As the aspect ratio is reduced, the ideal tokamak beta β (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as β ~ 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural elongation κ, which makes its plasma shape appear spherical, the ST configurationmore » can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to its longer term goal of attractive fusion energy power source. Since the start of the two megaampere class ST facilities in 2000, National Spherical Torus Experiment (NSTX) in the US and Mega Ampere Spherical Tokamak (MAST) in UK, active ST research has been conducted worldwide. More than sixteen ST research facilities operating during this period have achieved remarkable advances in all of fusion science areas, involving fundamental fusion energy science as well as innovation. These results suggest exciting future prospects for ST research both near term and longer term. The present paper reviews the scientific progress made by the worldwide ST research community during this new mega-ampere-ST era.« less

Electron density measurement of non-equilibrium atmospheric pressure plasma using dispersion interferometer

NASA Astrophysics Data System (ADS)

Yoshimura, Shinji; Kasahara, Hiroshi; Akiyama, Tsuyoshi

2017-10-01

Medical applications of non-equilibrium atmospheric plasmas have recently been attracting a great deal of attention, where many types of plasma sources have been developed to meet the purposes. For example, plasma-activated medium (PAM), which is now being studied for cancer treatment, has been produced by irradiating non-equilibrium atmospheric pressure plasma with ultrahigh electron density to a culture medium. Meanwhile, in order to measure electron density in magnetic confinement plasmas, a CO2 laser dispersion interferometer has been developed and installed on the Large Helical Device (LHD) at the National Institute for Fusion Science, Japan. The dispersion interferometer has advantages that the measurement is insensitive to mechanical vibrations and changes in neutral gas density. Taking advantage of these properties, we applied the dispersion interferometer to electron density diagnostics of atmospheric pressure plasmas produced by the NU-Global HUMAP-WSAP-50 device, which is used for producing PAM. This study was supported by the Grant of Joint Research by the National Institutes of Natural Sciences (NINS).

A high sensitivity momentum flux measuring instrument for plasma thruster exhausts and diffusive plasmas.

PubMed

West, Michael D; Charles, Christine; Boswell, Rod W

2009-05-01

A high sensitivity momentum flux measuring instrument based on a compound pendulum has been developed for use with electric propulsion devices and radio frequency driven plasmas. A laser displacement system, which builds upon techniques used by the materials science community for surface stress measurements, is used to measure with high sensitivity the displacement of a target plate placed in a plasma thruster exhaust. The instrument has been installed inside a vacuum chamber and calibrated via two different methods and is able to measure forces in the range of 0.02-0.5 mN with a resolution of 15 microN. Measurements have been made of the force produced from the cold gas flow and with a discharge ignited using argon propellant. The plasma is generated using a Helicon Double Layer Thruster prototype. The instrument target is placed about 1 mean free path for ion-neutral charge exchange collisions downstream of the thruster exit. At this position, the plasma consists of a low density ion beam (10%) and a much larger downstream component (90%). The results are in good agreement with those determined from the plasma parameters measured with diagnostic probes. Measurements at various flow rates show that variations in ion beam velocity and plasma density and the resulting momentum flux can be measured with this instrument. The instrument target is a simple, low cost device, and since the laser displacement system used is located outside the vacuum chamber, the measurement technique is free from radio frequency interference and thermal effects. It could be used to measure the thrust in the exhaust of other electric propulsion devices and the momentum flux of ion beams formed by expanding plasmas or fusion experiments.

Progress toward commissioning and plasma operation in NSTX-U

NASA Astrophysics Data System (ADS)

Ono, M.; Chrzanowski, J.; Dudek, L.; Gerhardt, S.; Heitzenroeder, P.; Kaita, R.; Menard, J. E.; Perry, E.; Stevenson, T.; Strykowsky, R.; Titus, P.; von Halle, A.; Williams, M.; Atnafu, N. D.; Blanchard, W.; Cropper, M.; Diallo, A.; Gates, D. A.; Ellis, R.; Erickson, K.; Hosea, J.; Hatcher, R.; Jurczynski, S. Z.; Kaye, S.; Labik, G.; Lawson, J.; LeBlanc, B.; Maingi, R.; Neumeyer, C.; Raman, R.; Raftopoulos, S.; Ramakrishnan, R.; Roquemore, A. L.; Sabbagh, S. A.; Sichta, P.; Schneider, H.; Smith, M.; Stratton, B.; Soukhanovskii, V.; Taylor, G.; Tresemer, K.; Zolfaghari, A.; The NSTX-U Team

2015-07-01

The National Spherical Torus Experiment-Upgrade (NSTX-U) is the most powerful spherical torus facility at PPPL, Princeton USA. The major mission of NSTX-U is to develop the physics basis for an ST-based Fusion Nuclear Science Facility (FNSF). The ST-based FNSF has the promise of achieving the high neutron fluence needed for reactor component testing with relatively modest tritium consumption. At the same time, the unique operating regimes of NSTX-U can contribute to several important issues in the physics of burning plasmas to optimize the performance of ITER. NSTX-U further aims to determine the attractiveness of the compact ST for addressing key research needs on the path toward a fusion demonstration power plant (DEMO). The upgrade will nearly double the toroidal magnetic field BT to 1 T at a major radius of R0 = 0.93 m, plasma current Ip to 2 MA and neutral beam injection (NBI) heating power to 14 MW. The anticipated plasma performance enhancement is a quadrupling of the plasma stored energy and near doubling of the plasma confinement time, which would result in a 5-10 fold increase in the fusion performance parameter nτ T. A much more tangential 2nd NBI system, with 2-3 times higher current drive efficiency compared to the 1st NBI system, is installed to attain the 100% non-inductive operation needed for a compact FNSF design. With higher fields and heating powers, the NSTX-U plasma collisionality will be reduced by a factor of 3-6 to help explore the favourable trend in transport towards the low collisionality FNSF regime. The NSTX-U first plasma is planned for the Summer of 2015, at which time the transition to plasma operations will occur.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiffen, Frederick W.; Noe, Susan P.; Snead, Lance Lewis

2014-10-01

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

AFE ion mass spectrometer design study

NASA Technical Reports Server (NTRS)

Wright, Willie

1989-01-01

This final technical report covers the activities engaged in by the University of Texas at Dallas, Center for Space Sciences in conjunction with the NASA Langley Research Center, Systems Engineering Division in design studies directed towards defining a suitable ion mass spectrometer to determine the plasma parameter around the Aeroassisted Flight Experiment vehicle during passage through the earth's upper atmosphere. Additional studies relate to the use of a Langmuir probe to measure windward ion/electron concentrations and temperatures. Selected instrument inlet subsystems were tested in the NASA Ames Arc-Jet Facility.

Progress in the Development of a High Power Helicon Plasma Source for the Materials Plasma Exposure Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulding, Richard Howell; Caughman, John B.; Rapp, Juergen

Proto-MPEX is a linear plasma device being used to study a novel RF source concept for the planned Material Plasma Exposure eXperiment (MPEX), which will address plasma-materials interaction (PMI) for nuclear fusion reactors. Plasmas are produced using a large diameter helicon source operating at a frequency of 13.56 MHz at power levels up to 120 kW. In recent experiments the helicon source has produced deuterium plasmas with densities up to ~6 × 1019 m–3 measured at a location 2 m downstream from the antenna and 0.4 m from the target. Previous plasma production experiments on Proto-MPEX have generated lower densitymore » plasmas with hollow electron temperature profiles and target power deposition peaked far off axis. The latest experiments have produced flat Te profiles with a large portion of the power deposited on the target near the axis. This and other evidence points to the excitation of a helicon mode in this case.« less

Spacelab

NASA Image and Video Library

1983-01-01

This photograph shows the Spacelab-1 module and Spacelab access turnel being installed in the cargo bay of orbiter Columbia for the STS-9 mission. The oribiting laboratory, built by the European Space Agency, is capable of supporting many types of scientific research that can best be performed in space. The Spacelab access tunnel, the only major piece of Spacelab hardware made in the U.S., connects the module with the mid-deck level of the orbiter cabin. The first Spacelab mission, Spacelab-1, sponsored jointly and shared equally by NASA and the European Space Agency, was a multidisciplinary mission; that is, investigations were performed in several different fields of scientific research. The overall goal of the mission was to verify Spacelab performance through a variety of scientific experiments. The disciplines represented by these experiments were: astronomy and solar physics, earth observations, space plasma physics, materials sciences, atmospheric physics, and life sciences. International in nature, Spacelab-1 conducted experiments from the United States, Japan, the Netherlands, United Kingdom, Beluga, France, Germany, Italy, and Switzerland. Spacelab-1, was launched from the Kennedy Space Center on November 28, 1983 aboard the orbiter Columbia (STS-9). The Marshall Space Flight Center was responsible for managing the Spacelab missions.

Streaked Thomson Scattering on Laboratory Plasma Jets

NASA Astrophysics Data System (ADS)

Banasek, Jacob; Byvank, Tom; Rocco, Sophia; Kusse, Bruce; Hammer, David

2017-10-01

Streaked Thomson scattering measurements have been performed on plasma jets created from a 15 μm thick radial Al or Ti foil load on COBRA, a 1 MA pulsed power machine. The goal was to measure the electron temperatures inside the center of the plasma jet created by the radial foil. The laser used for these measurements had a maximum energy of 10 J at 526.5 nm in a 3 ns duration pulse. Early experiments showed using the full energy significantly heats the 5 ×1018 cm-3 jet by inverse bremsstrahlung radiation. Here we used a streak camera to record the scattered spectrum and measure the evolving electron temperature of this laser heated jet. Analysis of the streak camera image showed that the electron temperature of the Al jet was increased from about 25 eV to 80-100 eV within about 2 ns. The Ti jets showed even stronger interaction with the laser, being heated to over 150 eV, and showed some heating even when only 1 J of laser energy was used. Also, the ion-acoustic peaks in the scattered spectrum from the Ti jets were significantly narrower than those from Al jets. Initial results will also be presented with scattered spectra taken at two different times within a single experiment by splitting the probe beam. This research is supported by the NNSA Stewardship Sciences Academic Programs under DOE Cooperative Agreement DE-NA0001836.

A PICKSC Science Gateway for enabling the common plasma physicist to run kinetic software

NASA Astrophysics Data System (ADS)

Hu, Q.; Winjum, B. J.; Zonca, A.; Youn, C.; Tsung, F. S.; Mori, W. B.

2017-10-01

Computer simulations offer tremendous opportunities for studying plasmas, ranging from simulations for students that illuminate fundamental educational concepts to research-level simulations that advance scientific knowledge. Nevertheless, there is a significant hurdle to using simulation tools. Users must navigate codes and software libraries, determine how to wrangle output into meaningful plots, and oftentimes confront a significant cyberinfrastructure with powerful computational resources. Science gateways offer a Web-based environment to run simulations without needing to learn or manage the underlying software and computing cyberinfrastructure. We discuss our progress on creating a Science Gateway for the Particle-in-Cell and Kinetic Simulation Software Center that enables users to easily run and analyze kinetic simulations with our software. We envision that this technology could benefit a wide range of plasma physicists, both in the use of our simulation tools as well as in its adaptation for running other plasma simulation software. Supported by NSF under Grant ACI-1339893 and by the UCLA Institute for Digital Research and Education.

Final Technical Report -- Bridging the PSI Knowledge Gap: A Multiscale Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whyte, Dennis

2014-12-12

The Plasma Surface Interactions (PSI) Science Center formed by the grant undertook a multidisciplinary set of studies on the complex interface between the plasma and solid states of matter. The strategy of the center was to combine and integrate the experimental, diagnostic and modeling toolkits from multiple institutions towards specific PSI problems. In this way the Center could tackle integrated science issues which were not addressable by single institutions, as well as evolve the underlying science of the PSI in a more general way than just for fusion applications. The overall strategy proved very successful. The research result and highlightsmore » of the MIT portion of the Center are primarily described. A particular highlight is the study of tungsten nano-tendril growth in the presence of helium plasmas. The Center research provided valuable new insights to the mechanisms controlling the nano-tendrils by developing coupled modeling and in situ diagnostic methods which could be directly compared. For example, the role of helium accumulation in tungsten distortion in the surface was followed with unique in situ helium concentration diagnostics developed. These depth-profiled, time-resolved helium concentration measurements continue to challenge the numerical models of nano-tendrils. The Center team also combined its expertise on tungsten nano-tendrils to demonstrate for the first time the growth of the tendrils in a fusion environment on the Alcator C-Mod fusion experiment, thus having significant impact on the broader fusion research effort. A new form of isolated nano-tendril “columns” were identified which are now being used to understand the underlying mechanisms controlling the tendril growth. The Center also advanced PSI science on a broader front with a particular emphasis on developing a wide range of in situ PSI diagnostic tools at the DIONISOS facility at MIT. For example the strong suppression of sputtering by the certain combination of light-species plasmas and metals was experimentally studied with independent measurement methods across the Center. This surprising result challenges the universal use of the binary-collision approximation in sputtering predictions and continues to be the subject of study. In order to address this issue MIT developed a new in situ erosion measurement technique based on ion beam analysis which can be used at elevated material temperatures. This exciting new technique is now being used to study material erosion in high performance plasma thrusters for space exploration and is being adopted to fusion experimental devices. This is an indicator of the positive synergies that arise from such a Center, with the research having impact beyond the initial area of study. The Center also served successfully as an organizing force for communication to the science community. The MIT members of the Center provided many high-profile overview presentations at prestigious international conferences and national workshops. The research resulted in three student theses and 24 peer-reviewed publications. PSI research continues to be identified as a critical area for fusion energy.« less

Overview and recent results of the Magnetized Shock Experiment (MSX)

NASA Astrophysics Data System (ADS)

Weber, T. E.; Smith, R. J.; Hsu, S. C.; Omelchenko, Y.

2015-11-01

Recent machine and diagnostics upgrades to the Magnetized Shock Experiment (MSX) at LANL have enabled unprecedented access to the physical processes arising from stagnating magnetized (β ~ 1), collisionless, highly supersonic (M ,MA ~ 10) flows, similar in dimensionless parameters to those found in both space and astrophysical shocks. Hot (100s of eV during translation), dense (1022 - 1023 m-3) Field Reversed Configuration (FRC) plasmoids are accelerated to high velocities (100s of km/s) and subsequently impact against a static target such as a strong parallel or anti-parallel (reconnection-wise) magnetic mirror, a solid obstacle, or neutral gas cloud to recreate the physics of interest with characteristic length and time scales that are both large enough to observe yet small enough to fit within the experiment. Long-lived (>50 μs) stagnated plasmas with density enhancement much greater than predicted by fluid theory (>4x) are observed, accompanied by discontinuous plasma structures indicating shocks and jetting (visible emission and interferometry) and copious >1 keV x-ray emission. An overview of the experimental program will be presented, including machine design and capabilities, diagnostics, and an examination of the physical processes that occur during stagnation against a variety of targets. Supported by the DOE Office of Fusion Energy Sciences under contract DE-AC52-06NA25369.

Laser experiments to simulate coronal mass ejection driven magnetospheres and astrophysical plasma winds on compact magnetized stars

NASA Astrophysics Data System (ADS)

Horton, W.; Ditmire, T.; Zakharov, Yu. P.

2010-06-01

Laboratory experiments using a plasma wind generated by laser-target interaction are proposed to investigate the creation of a shock in front of the magnetosphere and the dynamo mechanism for creating plasma currents and voltages. Preliminary experiments are shown where measurements of the electron density gradients surrounding the obstacles are recorded to infer the plasma winds. The proposed experiments are relevant to understanding the electron acceleration mechanisms taking place in shock-driven magnetic dipole confined plasmas surrounding compact magnetized stars and planets. Exploratory experiments have been published [P. Brady, T. Ditmire, W. Horton, et al., Phys. Plasmas 16, 043112 (2009)] with the one Joule Yoga laser and centimeter sized permanent magnets.

Commnity Petascale Project for Accelerator Science And Simulation: Advancing Computational Science for Future Accelerators And Accelerator Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spentzouris, Panagiotis; /Fermilab; Cary, John

The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessarymore » accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors.« less

Low-Temperature Plasma Coating for Aluminum

DTIC Science & Technology

2001-03-01

AFRL-ML-WP-TR-2001-4104 LOW-TEMPERATURE PLASMA COATING FOR ALUMINUM DR. HIROTSUGU YASUDA CENTER FOR SURFACE SCIENCE & PLASMA TECHNOLOGY...Date 00032001 Report Type N/A Dates Covered (from... to) - Title and Subtitle Low-Temperature Plasma Coating for Aluminum Contract Number...REPORT TYPE AND DATES COVERED Final, 6/29/1996 - 3/31/2001 4. TITLE AND SUBTITLE LOW-TEMPERATURE PLASMA COATING FOR ALUMINUM 5. FUNDING NUMBERS C

The 2017 Plasma Roadmap: Low temperature plasma science and technology

DOE PAGES

Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; ...

2017-07-14

Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The currentmore » state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.« less

The 2017 Plasma Roadmap: Low temperature plasma science and technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adamovich, I.; Baalrud, S. D.; Bogaerts, A.

Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The currentmore » state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.« less

Long-pulse power-supply system for EAST neutral-beam injectors

NASA Astrophysics Data System (ADS)

Liu, Zhimin; Jiang, Caichao; Pan, Junjun; Liu, Sheng; Xu, Yongjian; Chen, Shiyong; Hu, Chundong; NBI Team

2017-05-01

The long-pulse power-supply system equipped for the 4 MW beam-power ion source is comprised of three units at ASIPP (Institute of Plasma Physics, Chinese Academy of Sciences): one for the neutral-beam test stand and two for the EAST neutral-beam injectors (NBI-1 and NBI-2, respectively). Each power supply system consists of two low voltage and high current DC power supplies for plasma generation of the ion source, and two high voltage and high current DC power supplies for the accelerator grid system. The operation range of the NB power supply is about 80 percent of the design value, which is the safe and stable operation range. At the neutral-beam test stand, a hydrogen ion beam with a beam pulse of 150 s, beam power of 1.5 MW and beam energy of 50 keV was achieved during the long-pulse testing experiments. The result shows that the power-supply system meets the requirements of the EAST-NBIs fully and lays a basis for achieving plasma heating.

Validation metrics for turbulent plasma transport

DOE PAGES

Holland, C.

2016-06-22

Developing accurate models of plasma dynamics is essential for confident predictive modeling of current and future fusion devices. In modern computer science and engineering, formal verification and validation processes are used to assess model accuracy and establish confidence in the predictive capabilities of a given model. This paper provides an overview of the key guiding principles and best practices for the development of validation metrics, illustrated using examples from investigations of turbulent transport in magnetically confined plasmas. Particular emphasis is given to the importance of uncertainty quantification and its inclusion within the metrics, and the need for utilizing synthetic diagnosticsmore » to enable quantitatively meaningful comparisons between simulation and experiment. As a starting point, the structure of commonly used global transport model metrics and their limitations is reviewed. An alternate approach is then presented, which focuses upon comparisons of predicted local fluxes, fluctuations, and equilibrium gradients against observation. Furthermore, the utility of metrics based upon these comparisons is demonstrated by applying them to gyrokinetic predictions of turbulent transport in a variety of discharges performed on the DIII-D tokamak, as part of a multi-year transport model validation activity.« less

Modeling of reference operating scenario of GOL-NB multiple-mirror trap

DOE Office of Scientific and Technical Information (OSTI.GOV)

Postupaev, V. V., E-mail: V.V.Postupaev@inp.nsk.su; Yurov, D. V.

Currently, the GOL-NB multiple-mirror trap is being developed at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. The main scientific goal pursued by building GOL-NB is direct demonstration of suppression of longitudinal losses of particles and energy from the trap by using sections with a multiple-mirror magnetic field, which can be attached to the central gas-dynamic trap. Plasma heating in GOL-NB will be accomplished by neutral beam injection with a power of up to 1.5MW. The paper presents the first results of modeling the dynamics of the plasma parameters and fast ions under the reference operatingmore » scenario of the trap in which traditional short magnetic mirrors, rather than multiple-mirror sections, are attached to the central trap. In such a configuration, the plasma lifetime in the trap is expected to be minimal. The modeling was performed by using the DOL kinetic code. As a result, the initial conditions of the experiments are refined and the requirements to the system of maintaining the particle balance in the trap are determined.« less

Validation metrics for turbulent plasma transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, C.

Developing accurate models of plasma dynamics is essential for confident predictive modeling of current and future fusion devices. In modern computer science and engineering, formal verification and validation processes are used to assess model accuracy and establish confidence in the predictive capabilities of a given model. This paper provides an overview of the key guiding principles and best practices for the development of validation metrics, illustrated using examples from investigations of turbulent transport in magnetically confined plasmas. Particular emphasis is given to the importance of uncertainty quantification and its inclusion within the metrics, and the need for utilizing synthetic diagnosticsmore » to enable quantitatively meaningful comparisons between simulation and experiment. As a starting point, the structure of commonly used global transport model metrics and their limitations is reviewed. An alternate approach is then presented, which focuses upon comparisons of predicted local fluxes, fluctuations, and equilibrium gradients against observation. Furthermore, the utility of metrics based upon these comparisons is demonstrated by applying them to gyrokinetic predictions of turbulent transport in a variety of discharges performed on the DIII-D tokamak, as part of a multi-year transport model validation activity.« less

Planetary Science Enabled by High Power Ion Propulsion Systems from NASA's Prometheus Program

NASA Astrophysics Data System (ADS)

Cooper, John

2004-11-01

NASA's Prometheus program seeks to develop new generations of spacecraft nuclear-power and ion propulsion systems for applications to future planetary missions. The Science Definition Team for the first mission in the Prometheus series, the Jupiter Icy Moons Orbiter (JIMO), has defined science objectives for in-situ orbital exploration of the icy Galilean moons (Europa, Ganymede, Callisto) and the Jovian magnetosphere along with remote observations of Jupiter's atmosphere and aurorae, the volcanic moon Io, and other elements of the Jovian system. Important to this forum is that JIMO power and propulsion systems will need to be designed to minimize magnetic, radio, neutral gas, and plasma backgrounds that might otherwise interfere with achievement of mission science objectives. Another potential Prometheus mission of high science interest would be an extended tour of primitive bodies in the solar system, including asteroids, Jupiter family comets, Centaurs, and Kuiper Belt Objects (KBO). The final landed phase of this mission might include an active keplerian experiment for detectable (via downlink radio doppler shift) acceleration of a small kilometer-size Centaur or KBO object, likely the satellite of a larger object observable from Earth. This would have obvious application to testing of mitigation techniques for Earth impact hazards.

Nonlinear increase of X-ray intensities from thin foils irradiated with a 200 TW femtosecond laser

PubMed Central

Faenov, A. Ya.; Colgan, J.; Hansen, S. B.; Zhidkov, A.; Pikuz, T. A.; Nishiuchi, M.; Pikuz, S. A.; Skobelev, I. Yu.; Abdallah, J.; Sakaki, H.; Sagisaka, A.; Pirozhkov, A. S.; Ogura, K.; Fukuda, Y.; Kanasaki, M.; Hasegawa, N.; Nishikino, M.; Kando, M.; Watanabe, Y.; Kawachi, T.; Masuda, S.; Hosokai, T.; Kodama, R.; Kondo, K.

2015-01-01

We report, for the first time, that the energy of femtosecond optical laser pulses, E, with relativistic intensities I > 1021  W/cm2 is efficiently converted to X-ray radiation, which is emitted by “hot” electron component in collision-less processes and heats the solid density plasma periphery. As shown by direct high-resolution spectroscopic measurements X-ray radiation from plasma periphery exhibits unusual non-linear growth ~E4–5 of its power. The non-linear power growth occurs far earlier than the known regime when the radiation reaction dominates particle motion (RDR). Nevertheless, the radiation is shown to dominate the kinetics of the plasma periphery, changing in this regime (now labeled RDKR) the physical picture of the laser plasma interaction. Although in the experiments reported here we demonstrated by observation of KK hollow ions that X-ray intensities in the keV range exceeds ~1017  W/cm2, there is no theoretical limit of the radiation power. Therefore, such powerful X-ray sources can produce and probe exotic material states with high densities and multiple inner-shell electron excitations even for higher Z elements. Femtosecond laser-produced plasmas may thus provide unique ultra-bright X-ray sources, for future studies of matter in extreme conditions, material science studies, and radiography of biological systems. PMID:26330230

ADX: A high Power Density, Advanced RF-Driven Divertor Test Tokamak for PMI studies

NASA Astrophysics Data System (ADS)

Whyte, Dennis; ADX Team

2015-11-01

The MIT PSFC and collaborators are proposing an advanced divertor experiment, ADX; a divertor test tokamak dedicated to address critical gaps in plasma-material interactions (PMI) science, and the world fusion research program, on the pathway to FNSF/DEMO. Basic ADX design features are motivated and discussed. In order to assess the widest range of advanced divertor concepts, a large fraction (>50%) of the toroidal field volume is purpose-built with innovative magnetic topology control and flexibility for assessing different surfaces, including liquids. ADX features high B-field (>6 Tesla) and high global power density (P/S ~ 1.5 MW/m2) in order to access the full range of parallel heat flux and divertor plasma pressures foreseen for reactors, while simultaneously assessing the effect of highly dissipative divertors on core plasma/pedestal. Various options for efficiently achieving high field are being assessed including the use of Alcator technology (cryogenic cooled copper) and high-temperature superconductors. The experimental platform would also explore advanced lower hybrid current drive and ion-cyclotron range of frequency actuators located at the high-field side; a location which is predicted to greatly reduce the PMI effects on the launcher while minimally perturbing the core plasma. The synergistic effects of high-field launchers with high total B on current and flow drive can thus be studied in reactor-relevant boundary plasmas.

Nonlinear increase of X-ray intensities from thin foils irradiated with a 200 TW femtosecond laser

DOE PAGES

Faenov, A. Ya.; Colgan, J.; Hansen, S. B.; ...

2015-09-02

We report, for the first time, that the energy of femtosecond optical laser pulses, E, with relativistic intensities I > 10 21 W/cm 2 is efficiently converted to X-ray radiation, which is emitted by “hot” electron component in collision-less processes and heats the solid density plasma periphery. As shown by direct high-resolution spectroscopic measurements X-ray radiation from plasma periphery exhibits unusual non-linear growth ~E 4–5 of its power. The non-linear power growth occurs far earlier than the known regime when the radiation reaction dominates particle motion (RDR). Nevertheless, the radiation is shown to dominate the kinetics of the plasma periphery,more » changing in this regime (now labeled RDKR) the physical picture of the laser plasma interaction. Although in the experiments reported here we demonstrated by observation of KK hollow ions that X-ray intensities in the keV range exceeds ~10 17 W/cm 2, there is no theoretical limit of the radiation power. Therefore, such powerful X-ray sources can produce and probe exotic material states with high densities and multiple inner-shell electron excitations even for higher Z elements. As a result, femtosecond laser-produced plasmas may thus provide unique ultra-bright X-ray sources, for future studies of matter in extreme conditions, material science studies, and radiography of biological systems.« less

Laser-driven electron beam and radiation sources for basic, medical and industrial sciences.

PubMed

Nakajima, Kazuhisa

2015-01-01

To date active research on laser-driven plasma-based accelerators have achieved great progress on production of high-energy, high-quality electron and photon beams in a compact scale. Such laser plasma accelerators have been envisaged bringing a wide range of applications in basic, medical and industrial sciences. Here inheriting the groundbreaker's review article on "Laser Acceleration and its future" [Toshiki Tajima, (2010)],(1)) we would like to review recent progress of producing such electron beams due to relativistic laser-plasma interactions followed by laser wakefield acceleration and lead to the scaling formulas that are useful to design laser plasma accelerators with controllability of beam energy and charge. Lastly specific examples of such laser-driven electron/photon beam sources are illustrated.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheehey, P.T.; Faehl, R.J.; Kirkpatrick, R.C.

1997-12-31

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

Ion densities in Titan's ionosphere, multi-instrument case study

NASA Astrophysics Data System (ADS)

Shebanits, O.; Wahlund, J.-E.; Edberg, N. J. T.; Crary, F. J.; Wellbrock, A.; Coates, A. J.; Andrews, D. J.; Vigren, E.; Mandt, K. E.; Waite, J. H., Jr.

2015-10-01

The Cassini s/c in-situ plasma measurements of Titan's ionosphere by Radio and Plasma Wave Science (RPWS) Langmuir Probe (LP), Cassini Plasma Spectrometer (CAPS) Electron (ELS) and Ion Beam (IBS) are combined for selected flybys (T16, T29, T40& T56) to further constrain plasma parameters of ionosphere at altitudes 880-1400 km.

Russell Hulse, the First Binary Pulsar, and Science Education

Science.gov Websites

physics research. In 1977, Hulse changed fields from astrophysics to plasma physics and joined the Plasma discoverer of the first binary pulsar and co-recipient of the 1993 Nobel Prize in physics, will affiliate with The University of Texas at Dallas (UTD) as a visiting professor of physics and of science and math

Effect of different concentrations of dietary P and Ca on plasma inorganic P and urinary P excretion using noncolostomized and colostomized broilers.

PubMed

Manangi, Megharaja K; Maharjan, Pramir; Coon, Craig N

2018-02-01

Two 5-d bioassays were conducted to explore the P physiological threshold in broilers based on plasma inorganic P (iP), urinary P and Ca, and excreta P and Ca measurements in non-colostomized and colostomized broilers fed with different concentrations of non-phytate P (NPP) and Ca. In Experiment 1, 80 40-day-old Cobb 500 non-colostomized male broilers were assorted into 8 groups consisting of 10 broilers each and placed in individual metabolic cages. Similarly, 8 colostomized broilers of same age were allotted to 8 individual metabolic cages. The experimental diets consisted of a corn soybean meal basal containing 0.17% phytate P (PP) with 8 concentrations (0.08, 0.13, 0.18, 0.23, 0.28, 0.33, 0.38, and 0.45%) of NPP. The dietary Ca concentration was maintained at 0.5% by adjusting a 185-micron particle size limestone with each concentration of added P from added calcium phosphate, dibasic, monohydrate. After Experiment 1, broilers were fed a standard grower diet for 5 d and Experiment 2 was conducted the same as Experiment 1; however, Ca was maintained at 0.9% for all test diets. Plasma iP, urinary P and Ca, and total P (TP) and Ca retention along with phytate P hydrolysis were measured. At 0.5% Ca dietary level, the inflection points for dietary NPP obtained from segmented line regression analysis for plasma iP, urinary P, and urinary Ca were 0.26% (±0.04 SE), 0.28% (±0.01 SE), and 0.30% (±0.04 SE), respectively. The similar values for 0.9% Ca diets were 0.27% (±0.03 SE), 0.21% (±0.03 SE), and 0.30% (±0.0 SE), respectively. In summary, the present findings suggest that an increased dietary NPP would increase plasma inorganic P concentration along with increased % retention of TP and NPP until the broilers reach a point of physiological steady state (7.51 mg iP/dL - 8.13 mg iP/dL as found in this study). Excess P beyond physiological threshold is eliminated in urine coupled with decreased % retention. © 2017 Poultry Science Association Inc.

Observations of nonlinear and nonuniform kink dynamics in a laboratory flux rope

NASA Astrophysics Data System (ADS)

Sears, J.; Intrator, T.; Feng, Y.; Swan, H.; Gao, K.; Chapdelaine, L.

2013-12-01

A plasma column with axial magnetic field and current has helically twisted field lines. When current density in the column exceeds the kink instability threshold this magnetic configuration becomes unstable. Flux ropes in the solar wind and some solar prominences exhibit this topology, with their dynamics strongly and nonlinearly coupled to the ratio of axial current to magnetic field. The current-driven kink mode is ubiquitous in laboratory plasmas and well suited to laboratory study. In the Reconnection Scaling Experiment (RSX), nonlinear stability properties beyond the simple perturbative kink model are observed and readily diagnosed. We use a plasma gun to generate a single plasma column 0.50 m in length, in which we then drive an axial plasma current at the limit of marginal kink stability. With plasma current maintained at this threshold, we observe a deformation to a new dynamic equilibrium with finite gyration amplitude, where the currents and magnetic fields that support the force balance have surprising axial structure. Three dimensional measurements of magnetic field, plasma density, plasma potential, and ion flow velocity in the deformed plasma column show variation in the axial direction of the instability parameter and in the terms of the momentum equation. Likewise the pitch of the kink is measured to be nonuniform over the column length. In addition there is a return current antiparallel to the driven plasma current at distances up to 0.30 m from the gun that also modifies the force balance. These axial inhomogeneities, which are not considered in the model of an ideal kink, may be the terms that allow the deformed equilibrium of the RSX plasma to exist. Supported by DOE Office of Fusion Energy Sciences under LANS contract DE-AC52-06NA25369, NASA Geospace NNHIOA044I, Basic. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Overview of MST Research

NASA Astrophysics Data System (ADS)

Chapman, B. E.

2017-10-01

MST progress in advancing the RFP for (1) fusion plasma confinement with ohmic heating and minimal external magnetization, (2) predictive capability in toroidal confinement physics, and (3) basic plasma physics is summarized. Validation of key plasma models is a program priority, which is enhanced by programmable power supplies (PPS) to maximize inductive capability. The existing PPS enables access to very low plasma current, down to Ip =0.02 MA. This greatly expands the Lundquist number range S =104 -108 and allows nonlinear, 3D MHD computation using NIMROD and DEBS with dimensionless parameters that overlap those of MST plasmas. A new, second PPS will allow simultaneous PPS control of the Bp and Bt circuits. The PPS also enables MST tokamak operation, thus far focused on disruptions and RMP suppression of runaway electrons. Gyrokinetic modeling with GENE predicts unstable TEM in improved-confinement RFP plasmas. Measured fluctuations have TEM properties including a density-gradient threshold larger than for tokamak plasmas. Turbulent energization of an electron tail occurs during sawtooth reconnection. Probe measurements hint that drift waves are also excited via the turbulent cascade in standard RFP plasmas. Exploration of basic plasma science frontiers in MST RFP and tokamak plasmas is proposed as part of WiPPL, a basic science user facility. Work supported by USDoE.

Observations at mercury encounter by the plasma science experiment on mariner 10.

PubMed

Ogilvie, K W; Scudder, J D; Hartle, R E; Siscoe, G L; Bridge, H S; Lazarus, A J; Asbridge, J R; Bame, S J; Yeates, C M

1974-07-12

A fully developed bow shock and magnetosheath were observed near Mercury, providing unambiguous evidence for a strong interaction between Mercury and the solar wind. Inside the sheath there is a distinct region analogous to the magnetosphere or magnetotail of Earth, populated by electrons with lower density and higher temperature than the electrons observed in the solar wind or magnetosheath. At the time of encounter, conditions were such that a perpendicular shock was observed on the inbound leg and a parallel shock was observed on the outbound leg of the trajectory, and energetic plasma electron events were detected upstream from the outbound shock crossing. The interaction is most likely not atmospheric, but the data clearly indicate that the obstacle to solar wind flow is magnetic, either intrinsic or induced. The particle fluxes and energy spectra showed large variations while the spacecraft was inside the magnetosphere, and these variations could be either spatial or temporal.

Nano-Disperse Borides and Carbides: Plasma Technology Production, Specific Properties, Economic Evaluation

NASA Astrophysics Data System (ADS)

Galevskii, G. V.; Rudneva, V. V.; Galevskii, S. G.; Tomas, K. I.; Zubkov, M. S.

2016-04-01

The experience of production and study on properties of nano-disperse chromium and titanium borides and carbides, and silicon carbide has been generalized. The structure and special service aspects of utilized plasma-metallurgical complex equipped with a three-jet direct-flow reactor with a capacity of 150 kW have been outlined. Processing, heat engineering and service life characteristics of the reactor are specified. The synthesis parameters of borides and carbides, as well as their basic characteristics in nano-disperse condition and their production flow diagram are outlined. Engineering and economic performance of synthesizing borides in laboratory and industrial conditions is assessed, and the respective segment of the international market as well. The work is performed at State Siberian Industrial University as a project part of the State Order of Ministry of Science and Education of the Russian Federation No. 11.1531/2014/K.

Modeling of parasitic current collection by solar arrays in low-earth orbit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, V.A.; Gardner, B.M.; Guidice, D.A.

1996-11-01

In this paper we describe the development of a model of the electron current collected by solar arrays from the ionospheric plasma. This model will assist spacecraft designers in minimizing the impact of plasma interactions on spacecraft operations as they move to higher-voltage solar arrays. The model was developed by first examining in detail the physical processes of importance and then finding an analytic fit to the results over the parameter range of interest. The analytic model is validated by comparison with flight data from the Photovoltaic Array for Space Power Plus diagnostics (PASP Plus) flight experiment [D. A. Guidice,more » 34{ital th} {ital Aerospace} {ital Sciences} {ital Meeting} {ital and} {ital Exhibit}, Reno, NV, 1996, AIAA 96-0926 (American Institute of Aeronautics and Astronautics, Washington, DC, 1996)]. {copyright} {ital 1996 American Institute of Physics.}« less

KTX circuit model and discharge waveform prediction

NASA Astrophysics Data System (ADS)

Bai, Wei; Lan, T.; Mao, W. Z.; You, W.; Li, H.; Liu, A. D.; Xie, J. L.; Wan, S. D.; Liu, W. D.; Yang, L.; Fu, P.; Xiao, C. J.; Ding, W. X.

2013-10-01

The Keda Torus eXperiment (KTX) is a constructing reversed field pinch (RFP) device in University of Science and Technology of China. The KTX power supply system includes the Ohmic heating, field shaping and toroidal power supply systems, which produce the Ohmic field, equilibrium field and toroidal field, respectively. The detailed circuit model will be introduced in this poster. Another purpose is to predict its discharge waveforms using the modified Bessel function mode (MBFM), which describes the evolution of plasma current and magnetic flux in RFP base on Taylor theory. Furthermore, the power supply requirements of external field shaping winding are also predicted in the model, which will be very helpful for the design of plasma equilibrium controlling system. Supported by ITER-China program (No. 2011GB106000), NNSFC (Nos. 10990210, 10990211, 10335060 and 10905057), CPSF (No. 20080440104), YIF (No. WK2030040019) and KIPCAS (No. kjcx-yw-n28).

Nonlocal collisionless and collisional electron transport in low temperature plasmas

NASA Astrophysics Data System (ADS)

Kaganovich, Igor

2009-10-01

The purpose of the talk is to describe recent advances in nonlocal electron kinetics in low-pressure plasmas. A distinctive property of partially ionized plasmas is that such plasmas are always in a non-equilibrium state: the electrons are not in thermal equilibrium with the neutral species and ions, and the electrons are also not in thermodynamic equilibrium within their own ensemble, which results in a significant departure of the electron velocity distribution function from a Maxwellian. These non-equilibrium conditions provide considerable freedom to choose optimal plasma parameters for applications, which make gas discharge plasmas remarkable tools for a variety of plasma applications, including plasma processing, discharge lighting, plasma propulsion, particle beam sources, and nanotechnology. Typical phenomena in such discharges include nonlocal electron kinetics, nonlocal electrodynamics with collisionless electron heating, and nonlinear processes in the sheaths and in the bounded plasmas. Significant progress in understanding the interaction of electromagnetic fields with real bounded plasma created by this field and the resulting changes in the structure of the applied electromagnetic field has been one of the major achievements of the last decade in this area of research [1-3]. We show on specific examples that this progress was made possible by synergy between full scale particle-in-cell simulations, analytical models, and experiments. In collaboration with Y. Raitses, A.V. Khrabrov, Princeton Plasma Physics Laboratory, Princeton, NJ, USA; V.I. Demidov, UES, Inc., 4401 Dayton-Xenia Rd., Beavercreek, OH 45322, USA and AFRL, Wright-Patterson AFB, OH 45433, USA; and D. Sydorenko, University of Alberta, Edmonton, Canada. [4pt] [1] D. Sydorenko, A. Smolyakov, I. Kaganovich, and Y. Raitses, IEEE Trans. Plasma Science 34, 895 (2006); Phys. Plasmas 13, 014501 (2006); 14 013508 (2007); 15, 053506 (2008). [0pt] [2] I. D. Kaganovich, Y. Raitses, D. Sydorenko, and A. Smolyakov, Phys. Plasmas 14, 057104 (2007). [0pt] [3] V.I. Demidov, C.A. DeJoseph, and A.A. Kudryavtsev, Phys. Rev. Lett. 95, 215002 (2005); V.I. Demidov, C.A. DeJoseph, J. Blessington, and M.E. Koepke, Europhysics News, 38, 21 (2007).

The Norwegian Plasma Fractionation Project--a 12 year clinical and economic success story.

PubMed

Flesland, O; Seghatchian, J; Solheim, B G

2003-02-01

The establishment of the Norwegian Fractionation Project (Project) was of major importance in preserving national self-sufficiency when plasma, cryoprecipitate and small batch factor IX-concentrates were replaced by virus inactivated products in the last part of the 1980s. Fractionation was performed abroad by contract with Octapharma after tenders on the European market. All Norwegian blood banks (>50) participated in the Project. Total yearly production was 50-60 tons of mainly recovered plasma. From 1993 solvent detergent (SD) treated plasma has replaced other plasma for transfusion. The blood banks paid for the fractionation and/or viral inactivation process, while the plasma remained the property of the blood banks and the final products were returned to the blood banks. The Project sold surplus products to other Norwegian blood banks and the majority of the coagulation factor concentrates to The Institute of Haemophilia and Rikshospitalet University Hospital. Both plasma and blood bank quality was improved by the Project. Clinical experience with the products has been satisfactory and self-sufficiency has been achieved for all major plasma proteins and SD plasma, but a surplus exceeding 3 years consumption of albumin has accumulated due to decreasing clinical use.The Project has secured high yields of the fractionated products and the net income from the produced products is NOK 1115 (140 Euros or US dollars) per litre plasma. An increasing surplus of albumin and the possibility of significant sales abroad of currently not fractionated IVIgG, could lead to a reorganisation of the Project from that of a co-ordinator to a national plasma handling unit. This unit could buy the plasma from the blood banks and have the plasma fractionated by contract after tender, before selling the products back for cost recovery. The small blood banks could produce plasma for products for the Norwegian market, while surplus products from the larger blood banks which are certified for delivery of plasma for fractionation of products to be consumed in the European Community, could be sold on the international market. Copyright 2003 Elsevier Science Ltd.

Enabling interoperability in planetary sciences and heliophysics: The case for an information model

NASA Astrophysics Data System (ADS)

Hughes, J. Steven; Crichton, Daniel J.; Raugh, Anne C.; Cecconi, Baptiste; Guinness, Edward A.; Isbell, Christopher E.; Mafi, Joseph N.; Gordon, Mitchell K.; Hardman, Sean H.; Joyner, Ronald S.

2018-01-01

The Planetary Data System has developed the PDS4 Information Model to enable interoperability across diverse science disciplines. The Information Model is based on an integration of International Organization for Standardization (ISO) level standards for trusted digital archives, information model development, and metadata registries. Where controlled vocabularies provides a basic level of interoperability by providing a common set of terms for communication between both machines and humans the Information Model improves interoperability by means of an ontology that provides semantic information or additional related context for the terms. The information model was defined by team of computer scientists and science experts from each of the diverse disciplines in the Planetary Science community, including Atmospheres, Geosciences, Cartography and Imaging Sciences, Navigational and Ancillary Information, Planetary Plasma Interactions, Ring-Moon Systems, and Small Bodies. The model was designed to be extensible beyond the Planetary Science community, for example there are overlaps between certain PDS disciplines and the Heliophysics and Astrophysics disciplines. "Interoperability" can apply to many aspects of both the developer and the end-user experience, for example agency-to-agency, semantic level, and application level interoperability. We define these types of interoperability and focus on semantic level interoperability, the type of interoperability most directly enabled by an information model.

High-fidelity plasma codes for burn physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cooley, James; Graziani, Frank; Marinak, Marty

Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiation-hydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of self-heating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes, are a relatively recent computational tool that augments both experimental datamore » and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.« less

Active experiments in space; Proceedings of the Topical Meeting of the Interdisciplinary Scientific Commission D (Meeting D3) of the COSPAR 28th Plenary Meeting, The Hague, Netherlands, June 25-July 6, 1990

NASA Astrophysics Data System (ADS)

Torbert, R.

1992-12-01

The present volume on active experiments in space discusses dynamic trapping of electrons in the Porcupine ionospheric ion beam experiment, plasma wave observations during electron gun experiments on ISEE-1, spatial coherence and electromagnetic wave generation during electron beam experiments in space, and recent experimental measurements of space platform charging at LEO altitudes. Attention is given to high voltage spheres in an unmagnetized plasma, energetic ion emission for active spacecraft control, the collective gyration of a heavy ion cloud in a magnetized plasma, and remote sensing of artificial luminous clouds by lidars. Topics addressed include modulation of the background flux of energetic particles by artificial injection, wave measurements in active experiments on plasma beam injection, field formation around negatively biased solar arrays in the LEO-plasma, and the registration of ELF waves in rocket-satellite experiments with plasma injection.

Cold Atmospheric Plasma for Medicine: State of Research and Clinical Application

NASA Astrophysics Data System (ADS)

von Woedtke, Thomas

2015-09-01

Basic research in plasma medicine has made excellent progress and resulted in the fundamental insights that biological effects of cold atmospheric plasmas (CAP) are significantly caused by changes of the liquid environment of cells, and are dominated by redox-active species. First CAP sources are CE-certified as medical devices. Main focus of plasma application is on wound healing and treatment of infective skin diseases. Clinical applications in this field confirm the supportive effect of cold plasma treatment in acceleration of healing of chronic wounds above all in cases where conventional treatment fails. Cancer treatment is another actual and emerging field of CAP application. The ability of CAP to kill cancer cells by induction of apoptosis has been proved in vitro. First clinical applications of CAP in palliative care of cancer are realized. In collaboration with Hans-Robert Metelmann, University Medicine Greifswald; Helmut Uhlemann, Klinikum Altenburger Land GmbH Altenburg; Anke Schmidt and Kai Masur, Leibniz Institute for Plasma Science and Technology (INP Greifswald); Renate Schönebeck, Neoplas Tools GmbH Greifswald; and Klaus-Dieter Weltmann, Leibniz Institute for Plasma Science and Technology (INP Greifswald).

Effect of Time Dependent Bending of Current Sheets in Response to Generation of Plasma Jets and Reverse Currents

NASA Astrophysics Data System (ADS)

Frank, Anna

Magnetic reconnection is a basis for many impulsive phenomena in space and laboratory plasmas accompanied by effective transformation of magnetic energy. Reconnection processes usually occur in relatively thin current sheets (CSs), which separate magnetic fields of different or opposite directions. We report on recent observations of time dependent bending of CSs, which results from plasma dynamics inside the sheet. The experiments are carried out with the CS-3D laboratory device (Institute of General Physics RAS, Moscow) [1]. The CS magnetic structure with an X line provides excitation of the Hall currents and plasma acceleration from the X line to both side edges [2]. In the presence of the guide field By the Hall currents give rise to bending of the sheet: the peripheral regions located away from the X line are deflected from CS middle plane (z=0) in the opposite directions ±z [3]. We have revealed generation of reverse currents jy near the CS edges, i.e. the currents flowing in the opposite direction to the main current in the sheet [4]. There are strong grounds to believe that reverse currents are generated by the outflow plasma jets [5], accelerated inside the sheet and penetrated into the regions with strong normal magnetic field component Bz [4]. An impressive effect of sudden change in the sign of the CS bend has been disclosed recently, when analyzing distributions of plasma density [6] and current away from the X line, in the presence of the guide field By. The CS configuration suddenly becomes opposite from that observed at the initial stage, and this effect correlates well with generation of reverse currents. Consequently this effect can be related to excitation of the reverse Hall currents owing to generation of reverse currents jy in the CS. Hence it may be concluded that CSs may exhibit time dependent vertical z-displacements, and the sheet geometry depends on excitation of the Hall currents, acceleration of plasma jets and generation of reverse currents. The work was supported in part by the Program (OFN-15) “Plasma Processes in Space and Laboratory” of the Division of Physical Sciences of the Russian Academy of Sciences. 1. Frank A.G., Bogdanov S.Yu., Markov V.S. et al. // Phys. Plasmas 2005. 12, 052316(1-11). 2. Frank A.G., Bugrov S.G., Markov V.S. // Phys. Plasmas 2008. 15, 092102 (1-10). 3. Frank A.G., Bogdanov S.Yu., Dreiden G.V. et al. // Phys. Lett. A 2006. 348, 318-325. 4. Frank A.G., Kyrie N.P., Satunin S.N. // Phys. Plasmas 2011. 18, 111209 (1-9). 5. Kyrie N.P., Markov V.S., Frank A.G. // Plasma Phys. Reports 2010. 36, 357-364; JETP Lett. 2012. 95, 14-19. 6. Ostrovskaya G.V., Frank A.G. // Plasma Phys. Reports 2014. 40, 21-33.

The Plasma Interaction Experiment (PIX) description and test program. [electrometers

NASA Technical Reports Server (NTRS)

Ignaczak, L. R.; Haley, F. A.; Domino, E. J.; Culp, D. H.; Shaker, F. J.

1978-01-01

The plasma interaction experiment (PIX) is a battery powered preprogrammed auxiliary payload on the LANDSAT-C launch. This experiment is part of a larger program to investigate space plasma interactions with spacecraft surfaces and components. The varying plasma densities encountered during available telemetry coverage periods are deemed sufficient to determine first order interactions between the space plasma environment and the biased experimental surfaces. The specific objectives of the PIX flight experiment are to measure the plasma coupling current and the negative voltage breakdown characteristics of a solar array segment and a gold plated steel disk. Measurements will be made over a range of surface voltages up to plus or minus kilovolt. The orbital environment will provide a range of plasma densities. The experimental surfaces will be voltage biased in a preprogrammed step sequence to optimize the data returned for each plasma region and for the available telemetry coverage.

Preliminary feasibility study of pallet-only mode for magnetospheric and plasmas in space payloads, volume 4

NASA Technical Reports Server (NTRS)

1976-01-01

Results of studies performed on the magnetospheric and plasma portion of the AMPS are presented. Magnetospheric and plasma in space experiments and instruments are described along with packaging (palletization) concepts. The described magnetospheric and plasma experiments were considered as separate entities. Instrumentation ospheric and plasma experiments were considered as separate entities. Instrumentation requirements and operations were formulated to provide sufficient data for unambiguous interpretation of results without relying upon other experiments of the series. Where ground observations are specified, an assumption was made that large-scale additions or modifications to existing facilities were not required.

Using the Tritium Plasma Experiment to evaluate ITER PFC safety

NASA Astrophysics Data System (ADS)

Longhurst, Glen R.; Anderl, Robert A.; Bartlit, John R.; Causey, Rion A.; Haines, John R.

The Tritium Plasma Experiment was assembled at Sandia National Laboratories, Livermore to investigate interactions between dense plasmas at low energies and plasma-facing component materials. This apparatus has the unique capability of replicating plasma conditions in a tokamak divertor with particle flux densities of 2 x 10(exp 19) ions/((sq cm)(s)) and a plasma temperature of about 15 eV using a plasma that includes tritium. With the closure of the Tritium Research Laboratory at Livermore, the experiment was moved to the Tritium Systems Test Assembly facility at Los Alamos National Laboratory. An experimental program has been initiated there using the Tritium Plasma Experiment to examine safety issues related to tritium in plasma-facing components, particularly the ITER divertor. Those issues include tritium retention and release characteristics, tritium permeation rates and transient times to coolant streams, surface modification and erosion by the plasma, the effects of thermal loads and cycling, and particulate production. A considerable lack of data exists in these areas for many of the materials, especially beryllium, being considered for use in ITER. Not only will basic material behavior with respect to safety issues in the divertor environment be examined, but innovative techniques for optimizing performance with respect to tritium safety by material modification and process control will be investigated. Supplementary experiments will be carried out at the Idaho National Engineering Laboratory and Sandia National Laboratory to expand and clarify results obtained on the Tritium Plasma Experiment.

Ion and aerosol precursor densities in Titan's ionosphere: A multi-instrument case study

NASA Astrophysics Data System (ADS)

Shebanits, O.; Wahlund, J.-E.; Edberg, N. J. T.; Crary, F. J.; Wellbrock, A.; Andrews, D. J.; Vigren, E.; Desai, R. T.; Coates, A. J.; Mandt, K. E.; Waite, J. H.

2016-10-01

The importance of the heavy ions and dust grains for the chemistry and aerosol formation in Titan's ionosphere has been well established in the recent years of the Cassini mission. In this study we combine independent in situ plasma (Radio Plasma and Wave Science Langmuir Probe (RPWS/LP)) and particle (Cassini Plasma Science Electron Spectrometer, Cassini Plasma Science Ion Beam Spectrometer, and Ion and Neutral Mass Spectrometer) measurements of Titan's ionosphere for selected flybys (T16, T29, T40, and T56) to produce altitude profiles of mean ion masses including heavy ions and develop a Titan-specific method for detailed analysis of the RPWS/LP measurements (applicable to all flybys) to further constrain ion charge densities and produce the first empirical estimate of the average charge of negative ions and/or dust grains. Our results reveal the presence of an ion-ion (dusty) plasma below 1100 km altitude, with charge densities exceeding the primary ionization peak densities by a factor ≥2 in the terminator and nightside ionosphere (ne/ni ≤ 0.1). We suggest that ion-ion (dusty) plasma may also be present in the dayside ionosphere below 900 km (ne/ni < 0.5 at 1000 km altitude). The average charge of the dust grains (≥1000 amu) is estimated to be between -2.5 and -1.5 elementary charges, increasing toward lower altitudes.

DNA damage in oral cancer and normal cells induced by nitrogen atmospheric pressure plasma jets

NASA Astrophysics Data System (ADS)

Han, Xu; Kapaldo, James; Liu, Yueying; Stack, M. Sharon; Ptasinska, Sylwia

2015-09-01

Nitrogen atmospheric pressure plasma jets (APPJs) have been shown to effectively induce DNA double strand breaks in SCC25 oral cancer cells. The APPJ source constructed in our laboratory operates based on dielectric barrier discharge. It consists of two copper electrodes alternatively wrapping around a fused silica tube with nitrogen as a feed gas. It is generally more challenging to ignite plasma in N2 atmosphere than in noble gases. However, N2 provides additional advantages such as lower costs compared to noble gases, thus this design can be beneficial for the future long-term clinical use. To compare the effects of plasma on cancer cells (SCC25) and normal cells (OKF), the cells from both types were treated at the same experimental condition for various treatment times. The effective area with different damage levels after the treatment was visualized as 3D maps. The delayed damage effects were also explored by varying the incubation times after the treatment. All of these studies are critical for a better understanding of the damage responses of cellular systems exposed to the plasma radiation, thus are useful for the development of the advanced plasma cancer therapy. The research described herein was supported by the Division of Chemical Sciences, Geosciences and Biosciences, Basic Energy Sciences, Office of Science, United States Department of Energy through Grant No. DE-FC02-04ER15533.

Commissioning and Plans for the NSTX-U Facility

NASA Astrophysics Data System (ADS)

Ono, Masayuki; NSTX-U Team

2016-10-01

The National Spherical Torus Experiment - Upgrade (NSTX-U) has started its first year of plasma operations after the successful completion of the CD-4 milestones. The unique operating regimes of NSTX-U can contribute to several important issues in the physics of burning plasmas to optimize the performance of ITER. The major mission of NSTX-U is also to develop the physics and technology basis for an ST-based Fusion Nuclear Science Facility (FNSF). The new center stack will provide toroidal field of 1 Tesla at a major radius of 0.93 m which should enable a plasma current of up to 2 mega-Amp for 5 sec. A much more tangential 2nd NBI system, with 2-3 times higher current drive efficiency compared to the 1st NBI system, is installed. NSTX-U is designed to attain the 100% non-inductive operation needed for a compact FNSF design. With higher fields and heating powers of 14 MW, the NSTX-U plasma collisionality will be reduced by a factor of 3-6 to help explore the trend in transport towards the low collisionality FNSF regime. If the favorable trends observed on NSTX holds at low collisionality, high fusion neutron fluences could be achievable in very compact ST devices.

The effect of dietary betaine in Eimeria acervulina-infected chicks.

PubMed

Matthews, J O; Southern, L L

2000-01-01

Two experiments were conducted to evaluate the effect of dietary betaine in broiler chicks with either chronic (CHR; 2.5 x 10(5) sporulated oocysts on Day 1, 4, 7, and 10) or acute (ACT; 1.0 x 10(6) sporulated oocysts on Day 1) Eimeria acervulina infections. Three hundred (Experiment 1) or 600 (Experiment 2), 4-d-old male chicks were used in the 14-d experiments. In both experiments, a 2 x 3 factorial arrangement of treatments was used: two levels of betaine (0 or 0.075%) and three levels of coccidiosis infection (uninfected, CHR, or ACT). Each treatment was replicated five (Experiment 1) or 10 (Experiment 2) times with 10 chicks per replicate. In Experiment 1, the ACT infection decreased (P < 0.01) average daily gain and gain:feed, and the CHR infection decreased (P < 0.02) average daily gain. The ACT and CHR infections decreased (P < 0.06) Day 7 plasma carotenoids and Day 14 plasma total protein, and the ACT infection also decreased (P < 0.06) Day 7 plasma total protein. Average daily gain and Day 7 plasma total protein were increased in CHR chicks fed betaine but were decreased in uninfected chicks fed betaine (CHR x betaine; P < 0.09). Chicks fed betaine had decreased (P < 0.06) Day 7 plasma carotenoids. In Experiment 2 the CHR and ACT infections decreased (P < 0.01) average daily gain, average daily feed intake, grain:feed ratio, Days 7 and 14 plasma carotenoids, and Day 7 plasma total protein. Chicks fed betaine had increased (P < 0.07) average daily gains, gain:feed ratios, and lesion scores. Day 14 plasma carotenoids and plasma total protein were decreased in uninfected chicks fed betaine but were increased in CHR chicks fed betaine (CHR x betaine; P < 0.04); plasma carotenoids also were increased in ACT chicks fed betaine (ACT x betaine; P < 0.05). Betaine did not consistently affect growth performance, plasma constituents, or lesion score in CHR or ACT coccidiosis-infected chicks.

Negative ion and dust grain charge in Titan's ionosphere: multi-instrument case study

NASA Astrophysics Data System (ADS)

Shebanits, O.; Wahlund, J.-E.; Edberg, N. J. T.; Wellbrock, A.; Coates, A. J.; Crary, F.; Andrews, D.

2014-04-01

The Cassini s/c in-situ plasma measurements of Titan's ionosphere by Radio and Plasma Wave Science (RPWS) Langmuir Probe (LP), Cassini Plasma Spectrometer (CAPS) Electron (ELS) and Ion Beam (IBS) spectrometers are combined for selected flybys (T16, T20, T29, T40 and T56) to further constrain plasma parameters of ionosphere below 1400 km.

Views of Prospective Science Teachers on Including the Concept of Plasma in Science Curricula

ERIC Educational Resources Information Center

Balbag, Mustafa Zafer

2018-01-01

States of matter are structures that we may easily encounter in the universe as well as our close environment. The plasma state is the fourth state of matter, and it has much different properties in comparison to the solid, liquid and gas states of matter. In order to understand the universe and the environment we live in better, one needs to have…

Effect of Electron Energy Distribution on the Hysteresis of Plasma Discharge: Theory, Experiment, and Modeling.

PubMed

Lee, Hyo-Chang; Chung, Chin-Wook

2015-10-20

Hysteresis, which is the history dependence of physical systems, is one of the most important topics in physics. Interestingly, bi-stability of plasma with a huge hysteresis loop has been observed in inductive plasma discharges. Despite long plasma research, how this plasma hysteresis occurs remains an unresolved question in plasma physics. Here, we report theory, experiment, and modeling of the hysteresis. It was found experimentally and theoretically that evolution of the electron energy distribution (EED) makes a strong plasma hysteresis. In Ramsauer and non-Ramsauer gas experiments, it was revealed that the plasma hysteresis is observed only at high pressure Ramsauer gas where the EED deviates considerably from a Maxwellian shape. This hysteresis was presented in the plasma balance model where the EED is considered. Because electrons in plasmas are usually not in a thermal equilibrium, this EED-effect can be regarded as a universal phenomenon in plasma physics.

Effect of Electron Energy Distribution on the Hysteresis of Plasma Discharge: Theory, Experiment, and Modeling

PubMed Central

Lee, Hyo-Chang; Chung, Chin-Wook

2015-01-01

Hysteresis, which is the history dependence of physical systems, is one of the most important topics in physics. Interestingly, bi-stability of plasma with a huge hysteresis loop has been observed in inductive plasma discharges. Despite long plasma research, how this plasma hysteresis occurs remains an unresolved question in plasma physics. Here, we report theory, experiment, and modeling of the hysteresis. It was found experimentally and theoretically that evolution of the electron energy distribution (EED) makes a strong plasma hysteresis. In Ramsauer and non-Ramsauer gas experiments, it was revealed that the plasma hysteresis is observed only at high pressure Ramsauer gas where the EED deviates considerably from a Maxwellian shape. This hysteresis was presented in the plasma balance model where the EED is considered. Because electrons in plasmas are usually not in a thermal equilibrium, this EED-effect can be regarded as a universal phenomenon in plasma physics. PMID:26482650

A Fusion Nuclear Science Facility for a fast-track path to DEMO

DOE PAGES

Garofalo, Andrea M.; Abdou, M.; Canik, John M.; ...

2014-10-01

An accelerated fusion energy development program, a “fast-track” approach, requires developing an understanding of fusion nuclear science (FNS) in parallel with research on ITER to study burning plasmas. A Fusion Nuclear Science Facility (FNSF) in parallel with ITER provides the capability to resolve FNS feasibility issues related to power extraction, tritium fuel sustainability, and reliability, and to begin construction of DEMO upon the achievement of Q~10 in ITER. Fusion nuclear components, including the first wall (FW)/blanket, divertor, heating/fueling systems, etc. are complex systems with many inter-related functions and different materials, fluids, and physical interfaces. These in-vessel nuclear components must operatemore » continuously and reliably with: (a) Plasma exposure, surface particle & radiation loads, (b) High energy 2 neutron fluxes and their interactions in materials (e.g. peaked volumetric heating with steep gradients, tritium production, activation, atomic displacements, gas production, etc.), (c) Strong magnetic fields with temporal and spatial variations (electromagnetic coupling to the plasma including off-normal events like disruptions), and (d) a High temperature, high vacuum, chemically active environment. While many of these conditions and effects are being studied with separate and multiple effect experimental test stands and modeling, fusion nuclear conditions cannot be completely simulated outside the fusion environment. This means there are many new multi-physics, multi-scale phenomena and synergistic effects yet to be discovered and accounted for in the understanding, design and operation of fusion as a self-sustaining, energy producing system, and significant experimentation and operational experience in a true fusion environment is an essential requirement. In the following sections we discuss the FNSF objectives, describe the facility requirements and a facility concept and operation approach that can accomplish those objectives, and assess the readiness to construct with respect to several key FNSF issues: materials, steady-state operation, disruptions, power exhaust, and breeding blanket. Finally we present our conclusions.« less

Evaluation of propylene glycol and glycerol infusions as treatments for ketosis in dairy cows.

PubMed

Piantoni, P; Allen, M S

2015-08-01

To evaluate propylene glycol (PG) and glycerol (G) as potential treatments for ketosis, we conducted 2 experiments lasting 4 d each in which cows received one bolus infusion per day. Blood was collected before infusion, over 240min postinfusion, as well as 24 h postinfusion. Experiment 1 used 6 ruminally cannulated cows (26±7 d in milk) randomly assigned to 300-mL infusions of PG or G (both ≥99.5% pure) in a crossover design experiment with 2 periods. Within each period, cows were assigned randomly to infusion site sequence: abomasum (A)-cranial reticulorumen (R) or the reverse, R-A. Glucose precursors were infused into the R to simulate drenching and the A to prevent metabolism by ruminal microbes. Glycerol infused in the A increased plasma glucose concentration the most (15.8mg/dL), followed by PG infused in the R (12.6mg/dL), PG infused in the A (9.11mg/dL), and G infused in the R (7.3mg/dL). Infusion of PG into the R increased plasma insulin and insulin area under the curve (AUC) the most compared with all other treatments (7.88 vs. 2.13μIU/mL and 321 vs. 31.9min×μIU/mL, respectively). Overall, PG decreased plasma BHBA concentration after infusion (-6.46 vs. -4.55mg/dL) and increased BHBA AUC (-1,055 vs. -558min ×mg/dL) compared with G. Plasma NEFA responses were not different among treatments. Experiment 2 used 8 ruminally cannulated cows (22±5 d in milk) randomly assigned to treatment sequence in a Latin square design experiment balanced for carryover effects. Treatments were 300mL of PG, 300mL of G, 600mL of G (2G), and 300mL of PG + 300mL of G (GPG), all infused into the R. Treatment contrasts compared PG with each treatment containing glycerol (G, 2G, and GPG). Propylene glycol increased plasma glucose (14.0 vs. 5.35mg/dL) and insulin (7.59 vs. 1.11μIU/mL) concentrations compared with G, but only tended to increase glucose and insulin concentrations compared with 2G. Propylene glycol increased AUC for glucose (1,444 vs. 94.3mg/dL) and insulin (326 vs. 6.58min×μIU/mL) compared with G, and tended to increase insulin AUC compared with 2G. Propylene glycol was not different from GPG for glucose, insulin, or BHBA responses. Propylene glycol decreased plasma BHBA concentration (-10.3 vs. -4.21mg/dL) and increased BHBA AUC (-1,578 vs. -1.42min ×mg/dL) compared with G, but not compared with 2G. In general, and compared with G, GPG decreased plasma NEFA concentrations after infusions and PG decreased plasma NEFA concentrations early but not late after infusions. We conclude that a 300-mL dose of PG is more effective at increasing plasma glucose concentration than G and at least as effective as 600mL of G or a combination of G and PG when administered in the cranial reticulorumen. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

FOREWORD: 7th Symposium on Vacuum-based Science and Technology (SVBST2013)

NASA Astrophysics Data System (ADS)

Gulbiński, W.

2014-11-01

These are the proceedings of the 7th Symposium on Vacuum based Science and Technology organized in Kołobrzeg (PL) on November 19-21, 2013 by the Institute of Technology and Education, Koszalin University of Technology and the Clausius Tower Society under auspices of the Polish Vacuum Society (PTP) and the German Vacuum Society (DVG) and in collaboration with the BalticNet PlasmaTec and the Society of Vacuum Coaters (SVC). It was accompanied by the 12-th Annual Meeting of the German Vacuum Society. The mission of the Symposium is to provide a forum for presentation and exchange of expertise and research results in the field of vacuum and plasma science. After already six successful meetings organized alternately in Poland and Germany our goal is to continue and foster cooperation within the vacuum and plasma science community. This year, the Rudolf-Jaeckel Prize, awarded by the DVG for outstanding achievements in the field of vacuum based sciences, was presented to Dr Ute Bergner, president of the VACOM Vakuum Komponenten & Messtechnik GmbH and a member of our community. The full-day course organized in the framework of the Educational Program by the Society of Vacuum Coaters (SVC) and entitled: An Introduction to Physical Vapor Deposition (PVD) Processes was held on November 18, 2013 as a satellite event of the Symposium. The instructor was Prof. Ismat Shah from Delaware University (US). The Clausius Session, already traditionally organized during the Symposium was addressed this year to young generation. We invited our young colleagues to attend a series of educational lectures reporting on achievements in graphene science, scanning probe microscopy and plasma science. Lectures were given by: Prof. Jacek Baranowski from the Institute of Electronic Materials Technology in Warsaw, Prof. Teodor Gotszalk from the Wroclaw University of Technology and Prof. Holger Kersten from the Christian Albrechts University in Kiel. The Symposium was accompanied by an industry exhibition attended by the representatives of leading companies offering vacuum equipment, complete solutions for plasma based technology as well as advanced research equipment. Witold Gulbiński Michael Kopnarski Frank Richter Jan Walkowicz

Restrike Particle Beam Experiments on a Dense Plasma Focus. Opening Switch Research on a Dense Plasma Focus.

DTIC Science & Technology

1985-06-01

Research on this grant has focused on plasma focus experiments in the areas of particle beam generation and as a potential repetitive opening switch...as were scaling laws for the increase of electron energy and current with input energy. The potential of the plasma focus as an opening switch was...delay line technique. The observed frequencies were most consistent with the lower hybrid frequency. Keywords include: Dense Plasma Focus , Particle Beam Generation, Opening Switch, Load Experiments, Pulsed Power.

Overview of the Lockheed Martin Compact Fusion Reactor (CFR) Project

NASA Astrophysics Data System (ADS)

McGuire, Thomas

2017-10-01

The Lockheed Martin Compact Fusion Reactor (CFR) Program endeavors to quickly develop a compact fusion power plant with favorable commercial economics and military utility. The CFR uses a diamagnetic, high beta, magnetically encapsulated, linear ring cusp plasma confinement scheme. Major project activities will be reviewed, including the T4B and T5 plasma heating experiments. The goal of the experiments is to demonstrate a suitable plasma target for heating experiments, to characterize the behavior of plasma sources in the CFR configuration and to then heat the plasma with neutral beams, with the plasma transitioning into the high Beta confinement regime. The design and preliminary results of the experiments will be presented, including discussion of predicted behavior, plasma sources, heating mechanisms, diagnostics suite and relevant numerical modeling. ©2017 Lockheed Martin Corporation. All Rights Reserved.

Cold plasma processing of local planetary ores for oxygen and metallurgically important metals

NASA Technical Reports Server (NTRS)

Lynch, D. C.; Bullard, D.; Ortega, R.

1990-01-01

The utilization of a cold plasma in chlorination processing is described. Essential equipment and instruments were received, the experimental apparatus assembled and tested, and preliminary experiments conducted. The results of the latter lend support to the original hypothesis: a cold plasma can both significantly enhance and bias chemical reactions. In two separate experiments, a cold plasma was used to reduce TiCl4 vapor and chlorinate ilmenite. The latter, reacted in an argon-chlorine plasma, yielded oxygen. The former experiment reveals that chlorine can be recovered as HCl vapor from metal chlorides in a hydrogen plasma. Furthermore, the success of the hydrogen experiments has lead to an analysis of the feasibility of direct hydrogen reduction of metal oxides in a cold plasma. That process would produce water vapor and numerous metal by-products.

Laser-driven electron beam and radiation sources for basic, medical and industrial sciences

PubMed Central

NAKAJIMA, Kazuhisa

2015-01-01

To date active research on laser-driven plasma-based accelerators have achieved great progress on production of high-energy, high-quality electron and photon beams in a compact scale. Such laser plasma accelerators have been envisaged bringing a wide range of applications in basic, medical and industrial sciences. Here inheriting the groundbreaker’s review article on “Laser Acceleration and its future” [Toshiki Tajima, (2010)],1) we would like to review recent progress of producing such electron beams due to relativistic laser-plasma interactions followed by laser wakefield acceleration and lead to the scaling formulas that are useful to design laser plasma accelerators with controllability of beam energy and charge. Lastly specific examples of such laser-driven electron/photon beam sources are illustrated. PMID:26062737

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

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 inadequatemore » 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.« less

ECH Technology Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Temkin, Richard

2014-12-24

Electron Cyclotron Heating (ECH) is needed for plasma heating, current drive, plasma stability control, and other applications in fusion energy sciences research. The program of fusion energy sciences supported by U. S. DOE, Office of Science, Fusion Energy Sciences relies on the development of ECH technology to meet the needs of several plasma devices working at the frontier of fusion energy sciences research. The largest operating ECH system in the world is at DIII-D, consisting of six 1 MW, 110 GHz gyrotrons capable of ten second pulsed operation, plus two newer gyrotrons. The ECH Technology Development research program investigated themore » options for upgrading the DIII-D 110 GHz ECH system. Options included extending present-day 1 MW technology to 1.3 – 1.5 MW power levels or developing an entirely new approach to achieve up to 2 MW of power per gyrotron. The research consisted of theoretical research and designs conducted by Communication and Power Industries of Palo Alto, CA working with MIT. Results of the study would be validated in a later phase by research on short pulse length gyrotrons at MIT and long pulse / cw gyrotrons in industry. This research follows a highly successful program of development that has led to the highly reliable, six megawatt ECH system at the DIII-D tokamak. Eventually, gyrotrons at the 1.5 megawatt to multi-megawatt power level will be needed for heating and current drive in large scale plasmas including ITER and DEMO.« less

Plasma Interactions with Mixed Materials and Impurity Transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rognlien, T. D.; Beiersdorfer, Peter; Chernov, A.

2016-10-28

The project brings together three discipline areas at LLNL to develop advanced capability to predict the impact of plasma/material interactions (PMI) on metallic surfaces in magnetic fusion energy (MFE) devices. These areas are (1) modeling transport of wall impurity ions through the edge plasma to the core plasma, (2) construction of a laser blow-off (LBO) system for injecting precise amounts of metallic atoms into a tokamak plasma, and (3) material science analysis of fundamental processes that modify metallic surfaces during plasma bombardment. The focus is on tungsten (W), which is being used for the ITER divertor and in designs ofmore » future MFE devices. In area (1), we have worked with the University of California, San Diego (UCSD) on applications of the UEDGE/DUSTT coupled codes to predict the influx of impurity ions from W dust through the edge plasma, including periodic edge-plasma oscillations, and revived a parallel version of UEDGE to speed up these simulations. In addition, the impurity transport model in the 2D UEDGE code has been implemented into the 3D BOUT++ turbulence/transport code to allow fundamental analysis of the impact of strong plasma turbulence on the impurity transport. In area (2), construction and testing of the LBO injection system has been completed. The original plan to install the LBO on the National Spherical Torus Experiment Upgrade (NSTX-U) at Princeton and its use to validate the impurity transport simulations is delayed owing to NSTX-U being offline for substantial magnetic coil repair period. In area (3), an analytic model has been developed to explain the growth of W tendrils (or fuzz) observed for helium-containing plasmas. Molecular dynamics calculations of W sputtering by W and deuterium (D) ions shows that a spatial blending of interatomic potentials is needed to describe the near-surface and deeper regions of the material.« less

Final Technical Report for the Center for Momentum Transport and Flow Organization (CMTFO)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forest, Cary B.; Tynan, George R.

The Center for Momentum Transport and Flow Organization (CMTFO) is a DOE Plasma Science Center formed in late 2009 to focus on the general principles underlying momentum transport in magnetic fusion and astrophysical systems. It is composed of funded researchers from UCSD, UW Madison, U. Colorado, PPPL. As of 2011, UCSD supported postdocs are collaborating at MIT/Columbia and UC Santa Cruz and beginning in 2012, will also be based at PPPL. In the initial startup period, the Center supported the construction of two basic experiments at PPPL and UW Madison to focus on accretion disk hydrodynamic instabilities and solar physicsmore » issues. We now have computational efforts underway focused on understanding recent experimental tests of dynamos, solar tacholine physics, intrinsic rotation in tokamak plasmas and L-H transition physics in tokamak devices. In addition, we have the basic experiments discussed above complemented by work on a basic linear plasma device at UCSD and a collaboration at the LAPD located at UCLA. We are also performing experiments on intrinsic rotation and L-H transition physics in the DIII-D, NSTX, C-Mod, HBT EP, HL-2A, and EAST tokamaks in the US and China, and expect to begin collaborations on K-STAR in the coming year. Center funds provide support to over 10 postdocs and graduate students each year, who work with 8 senior faculty and researchers at their respective institutions. The Center has sponsored a mini-conference at the APS DPP 2010 meeting, and co-sponsored the recent Festival de Theorie (2011) with the CEA in Cadarache, and will co-sponsor a Winter School in January 2012 in collaboration with the CMSO-UW Madison. Center researchers have published over 50 papers in the peer reviewed literature, and given over 10 talks at major international meetings. In addition, the Center co-PI, Professor Patrick Diamond, shared the 2011 Alfven Prize at the EPS meeting. Key scientific results from this startup period include initial simulations of the effects of boundary conditions on turbulent dynamo experiments; simulations of intrinsic rotation showing the strong link between toroidal rotation and temperature gradients and elucidation of the turbulence symmetry breaking mechanisms that lead to this macroscopic behavior; first experiments in a large tokamak testing the roll of turbulent momentum transport in driving intrinsic rotation; experiments in tokamaks showing strong evidence that zonal flows, together with the more widely recognized mean sheared ExB flow, act to trigger the L-H transition in tokamak devices and the first experimental measurement of collisional viscosity in an unmagnetized plasma. In the coming three year period, we will continue these efforts by a combination of basic hydrodynamic, liquid metal and plasma experiments combined with experiments on numerous tokamak devices around the world. In addition, we will use MHD, gyrofluid and gyrokinetic codes combined with theory to address the problems of interest to the Center.« less

Center for Momentum Transport and Flow Organization (CMTFO). Final technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tynan, George R.; Diamond, P. H.; Ji, H.

The Center for Momentum Transport and Flow Organization (CMTFO) is a DOE Plasma Science Center formed in late 2009 to focus on the general principles underlying momentum transport in magnetic fusion and astrophysical systems. It is composed of funded researchers from UCSD, UW Madison, U. Colorado, PPPL. As of 2011, UCSD supported postdocs are collaborating at MIT/Columbia and UC Santa Cruz and beginning in 2012, will also be based at PPPL. In the initial startup period, the Center supported the construction of two basic experiments at PPPL and UW Madison to focus on accretion disk hydrodynamic instabilities and solar physicsmore » issues. We now have computational efforts underway focused on understanding recent experimental tests of dynamos, solar tachocline physics, intrinsic rotation in tokamak plasmas and L-H transition physics in tokamak devices. In addition, we have the basic experiments discussed above complemented by work on a basic linear plasma device at UCSD and a collaboration at the LAPD located at UCLA. We are also performing experiments on intrinsic rotation and L-H transition physics in the DIII-D, NSTX, C-Mod, HBT EP, HL-2A, and EAST tokamaks in the US and China, and expect to begin collaborations on K-STAR in the coming year. Center funds provide support to over 10 postdocs and graduate students each year, who work with 8 senior faculty and researchers at their respective institutions. The Center has sponsored a mini-conference at the APS DPP 2010 meeting, and co-sponsored the recent Festival de Theorie (2011) with the CEA in Cadarache, and will co-sponsor a Winter School in January 2012 in collaboration with the CMSO-UW Madison. Center researchers have published over 50 papers in the peer reviewed literature, and given over 10 talks at major international meetings. In addition, the Center co-PI, Professor Patrick Diamond, shared the 2011 Alfven Prize at the EPS meeting. Key scientific results from this startup period include initial simulations of the effects of boundary conditions on turbulent dynamo experiments; simulations of intrinsic rotation showing the strong link between toroidal rotation and temperature gradients and elucidation of the turbulence symmetry breaking mechanisms that lead to this macroscopic behavior; first experiments in a large tokamak testing the roll of turbulent momentum transport in driving intrinsic rotation; experiments in tokamaks showing strong evidence that zonal flows, together with the more widely recognized mean sheared ExB flow, act to trigger the L-H transition in tokamak devices and the first experimental measurement of collisional viscosity in an unmagnetized plasma. In the coming three year period, we will continue these efforts by a combination of basic hydrodynamic, liquid metal and plasma experiments combined with experiments on numerous tokamak devices around the world. In addition, we will use MHD, gyrofluid and gyrokinetic codes combined with theory to address the problems of interest to the Center.« less

Pre-launch simulation experiment of microwave-ionosphere nonlinear interaction rocket experiment in the space plasma chamber

NASA Astrophysics Data System (ADS)

Kaya, N.; Tsutsui, M.; Matsumoto, H.; Kimura, I.

1980-09-01

A pre-flight test experiment of a microwave-ionosphere nonlinear interaction rocket experiment (MINIX) has been carried out in a space plasma simulation chamber. Though the first rocket experiment ended up in failure because of a high voltage trouble, interesting results are observed in the pre-flight experiment. A significant microwave heating of plasma up to 300% temperature increase is observed. Strong excitations of plasma waves by the transmitted microwaves in the VLF and HF range are observed as well. These microwave effects may have to be taken into account in solar power satellite projects in the future.

Recent Progress on Spherical Torus Research and Implications for Fusion Energy Development Path

NASA Astrophysics Data System (ADS)

Ono, Masayuki

2014-10-01

The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A =R0 / a) reduced to A near 1.5, well below the normal tokamak operating range of A equal to 2.5 or greater. As the aspect ratio is reduced, the ideal tokamak beta (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural plasma elongation which makes its plasma shape appear spherical, the ST configuration can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to the longer term goal of an attractive fusion energy power source. Since the start of the two mega-ampere class ST facilities in 2000, the National Spherical Torus Experiment (NSTX) in the US and Mega Ampere Spherical Tokamak (MAST) in the UK, active ST research has been conducted worldwide. More than sixteen ST research facilities operating during this period have achieved remarkable advances in all areas of fusion research, including fundamental fusion energy science as well as technological innovation. These results suggest exciting future prospects for ST research in both the near and longer term. The talk will summarize the key physics results from worldwide ST experiments, and describe ST community plans to provide the database for FNSF design while improving predictive capabilities for ITER and beyond. This work supported by DoE Contract No. DE-AC02-09CH11466.

Secretion of glucagon-like peptide-2 responds to nutrient intake but not glucose provision in milk-fed calves.

PubMed

Castro, J J; Morrison, S Y; Hosseinni, A; Loor, J J; Drackley, J K; Ipharraguerre, I R

2016-07-01

Glucagon-like peptide 2 (GLP-2) is a peptide released by the lower gut that has potent trophic and restorative effects on the intestinal epithelium. Two experiments were conducted to assess the effects of feeding rate and either metabolizable or nonmetabolizable glucose supplementation on GLP-2 concentrations in plasma and intestinal development in Holstein calves. In the first experiment, 48 newborn calves were assigned to 12 treatments (n=4) corresponding to the factorial combination of 4 milk feeding amounts [1.75, 1.32, 0.88, and 0.44% of body weight (BW) as dry matter (DM)] and 3 oral supplementation treatments (nonsupplemented, glucose-supplemented, and 3-O-methyl glucose-supplemented). In the second experiment 30 newborn calves (n=10) were fed milk at a fixed rate of 1.75% of BW as DM and assigned to the same glucose supplementation treatments used in experiment 1 to investigate effects on intestinal development. In the first experiment, we found a saturating response of plasma GLP-2 to increasing feeding levels. The feeding rate at which 50% of the maximal GLP-2 release occurred was estimated to be 0.53% of BW as DM or 30.3% of the maximum feeding rate (1.75% of BW as DM), whereas maximal secretion was estimated to be about 98.6 pmol/L. In turn, feeding 75, 50, or 25% of the maximal feeding rate (i.e., 1.75% BW as DM) resulted in plasma GLP-2 concentrations 87, 72, and 49% of that in fully fed calves, respectively. Neither metabolizable nor nonmetabolizable glucose supplementation affected GLP-2 secretion and no interaction with feed intake level was detected. In the second experiment, no effect of glucose supplementation was observed on intestinal growth, mucosal cell proliferation, or expression of genes related to the actions of GLP-2. Nonetheless, we observed that a pool of genes of the GLP-2 signaling pathway was more abundantly and coordinately regulated in the colon than in the ileum of these animals, indicating an opportunity for dietary induction of the peptide in this organ. In conclusion, during this experiment, plasma GLP-2 concentrations responded in a diminishing return fashion to milk intake but not to glucose supplementation, even at milk consumption levels of only 0.4% of BW as DM. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A Technique to Eliminate External Transport Barriers and Stabilize Fiscal Instabilities

NASA Astrophysics Data System (ADS)

Heeter, Robert F.

1997-11-01

The case is made for a coordinated national effort to diffuse plasma science knowledge to the public. Like earlier "fiscal instabilities" in plasma research, the 1995-7 magnetic fusion budget disruption can be attributed to a lack of public awareness about the value of science research, as reflected in the attitude of Congress. Magnetic fusion researchers now create "internal transport barriers" to reduce plasma heat loss, but observations also reveal a problematic "external transport barrier" in all of plasma science - the inadequate diffusion of knowledge beyond the scientists. Public funding creates scientific knowledge for the public good, and now the public cares - and deserves to know - what it pays for. Eliminating the external transport barrier should suppress the fiscal instability: theory predicts that funding should stabilize - or even increase - if the value of plasma science is understood by the bulk of Congress' members before they're elected, rather than just a small population of patrons energetically lobbied in office. If the public understands the value of plasma research, Congress will too. But plasmas are poorly represented in both contemporary classrooms and public perception. To reach the "Lawson Criterion" for ignition of public understanding, we should reach out to the public and to educators nationwide. Education and outreach activities are, and ought to be, part of the professional life of a plasma scientist. Our current activities consist largely of teaching our own classes, writing papers, lobbying Congress, giving lab tours, making Web pages, and promoting education locally; these have been useful, but insufficient. Now we must do better. To stabilize fiscal instabilities for good, we should restructure not only our research programs, but our sense of what it means to be a scientist. We should coordinate our education and outreach activities on a national scale, maximizing impact while minimizing cost in time, labor, and money. To this end our existing education and outreach activities are evaluated, and new activities are suggested. A coordinated education and outreach effort is sketched, involving the DPP, the DOE, labs and universities, and everyone from our senior management to our enthusiastic students. A modification of the professional physics pipeline is proposed to encourage recruitment, retention, and development of scientists who are not only sources of new knowledge, but who also conduct, convect, and radiate their knowledge to others. The implantation of plasma topics and examples into the educational system is advocated, not to make learning harder, but so plasmas are actually treated as the fourth state of matter. If younger scientists adopt this "Coordinated Civic Science" professional spirit, and older scientists and program leaders support it, we should succeed.

Arginine affects appetite via nitric oxide in ducks.

PubMed

Wang, C; Hou, S S; Huang, W; Xu, T S; Rong, G H; Xie, M

2014-08-01

The objective of the study was to investigate the mechanism by which arginine regulates feed intake in Pekin ducks. In experiment 1, one hundred forty-four 1-d-old male Pekin ducks were randomly allotted to 3 dietary treatments with 6 replicate pens of 8 birds per pen. Birds in each group were fed a corn-corn gluten meal diet containing 0.65, 0.95, and 1.45% arginine. Ducks fed the diet containing 0.65% arginine had lower feed intake and plasma nitric oxide level (P < 0.05) than the other 2 groups. In experiment 2, twenty 11-d-old ducks were allotted to 1 of 2 treatments. After 2 h fasting, birds in the 2 groups were intraperitoneally administrated saline and l-NG-nitro-arginine methyl ester HCl (L-NAME) for 3 d, respectively. Feed intake (P < 0.07) and plasma nitric oxide concentration (P < 0.05) 2 h postinjection in the L-NAME administered group were lower than those of the control group. In conclusion, the study implied that arginine modifies feeding behavior possibly through controlling endogenous synthesis of nitric oxide in Pekin ducks. © Poultry Science Association Inc.

Molecular systems under shock compression into the dense plasma regime: carbon dioxide and hydrocarbon polymers

NASA Astrophysics Data System (ADS)

Mattsson, Thomas R.; Cochrane, Kyle R.; Root, Seth; Carpenter, John H.

2013-10-01

Density Functional Theory (DFT) has proven remarkably accurate in predicting properties of matter under shock compression into the dense plasma regime. Materials where chemistry plays a role are of interest for many applications, including planetary science and inertial confinement fusion (ICF). As examples of systems where chemical reactions are important, and demonstration of the high fidelity possible for these both structurally and chemically complex systems, we will discuss shock- and re-shock of liquid carbon dioxide (CO2) in the range 100 to 800 GPa and shock compression of hydrocarbon polymers, including GDP (glow discharge polymer) which is used as an ablator in laser ICF experiments. Experimental results from Sandia's Z machine validate the DFT simulations at extreme conditions and the combination of experiment and DFT provide reliable data for evaluating existing and constructing future wide-range equations of state models for molecular compounds. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Enhancing Understanding of Magnetized High Energy Density Plasmas from Solid Liner Implosions Using Fluid Modeling with Kinetic Closures

NASA Astrophysics Data System (ADS)

Masti, Robert; Srinivasan, Bhuvana; King, Jacob; Stoltz, Peter; Hansen, David; Held, Eric

2017-10-01

Recent results from experiments and simulations of magnetically driven pulsed power liners have explored the role of early-time electrothermal instability in the evolution of the MRT (magneto-Rayleigh-Taylor) instability. Understanding the development of these instabilities can lead to potential stabilization mechanisms; thereby providing a significant role in the success of fusion concepts such as MagLIF (Magnetized Liner Inertial Fusion). For MagLIF the MRT instability is the most detrimental instability toward achieving fusion energy production. Experiments of high-energy density plasmas from wire-array implosions have shown the requirement for more advanced physics modeling than that of ideal magnetohydrodynamics. The overall focus of this project is on using a multi-fluid extended-MHD model with kinetic closures for thermal conductivity, resistivity, and viscosity. The extended-MHD model has been updated to include the SESAME equation-of-state tables and numerical benchmarks with this implementation will be presented. Simulations of MRT growth and evolution for MagLIF-relevant parameters will be presented using this extended-MHD model with the SESAME equation-of-state tables. This work is supported by the Department of Energy Office of Science under Grant Number DE-SC0016515.

The concept of a facility for cosmic dust research on the International Space Station

NASA Technical Reports Server (NTRS)

Blum, Juergen; Cabane, Michel; Fonda, Mark; Giovane, Frank; Gustafson, Bo A. S.; Keller, Horst U.; Markiewicz, Wojciech J.; Levasseur-Regourd, Any-Chantal; Worms, Jean-Claude; Nuth, Joseph A.;

Characteristics of a high-power RF source of negative hydrogen ions for neutral beam injection into controlled fusion devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdrashitov, G. F.; Belchenko, Yu. I.; Gusev, I. A.

An injector of hydrogen atoms with an energy of 0.5–1 MeV and equivalent current of up to 1.5 A for purposes of controlled fusion research is currently under design at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. Within this project, a multiple-aperture RF surface-plasma source of negative hydrogen ions is designed. The source design and results of experiments on the generation of a negative ion beam with a current of >1 A in the long-pulse mode are presented.

Plasma Treatment to Remove Carbon from Indium UV Filters

NASA Technical Reports Server (NTRS)

Greer, Harold F.; Nikzad, Shouleh; Beasley, Matthew; Gantner, Brennan

2012-01-01

The sounding rocket experiment FIRE (Far-ultraviolet Imaging Rocket Experiment) will improve the science community fs ability to image a spectral region hitherto unexplored astronomically. The imaging band of FIRE (.900 to 1,100 Angstroms) will help fill the current wavelength imaging observation hole existing from approximately equal to 620 Angstroms to the GALEX band near 1,350 Angstroms. FIRE is a single-optic prime focus telescope with a 1.75-m focal length. The bandpass of 900 to 1100 Angstroms is set by a combination of the mirror coating, the indium filter in front of the detector, and the salt coating on the front of the detector fs microchannel plates. Critical to this is the indium filter that must reduce the flux from Lymanalpha at 1,216 Angstroms by a minimum factor of 10(exp -4). The cost of this Lyman-alpha removal is that the filter is not fully transparent at the desired wavelengths of 900 to 1,100 Angstroms. Recently, in a project to improve the performance of optical and solar blind detectors, JPL developed a plasma process capable of removing carbon contamination from indium metal. In this work, a low-power, low-temperature hydrogen plasma reacts with the carbon contaminants in the indium to form methane, but leaves the indium metal surface undisturbed. This process was recently tested in a proof-of-concept experiment with a filter provided by the University of Colorado. This initial test on a test filter showed improvement in transmission from 7 to 9 percent near 900 with no process optimization applied. Further improvements in this performance were readily achieved to bring the total transmission to 12% with optimization to JPL's existing process.

Physics Criteria for a Subscale Plasma Liner Experiment

DOE PAGES

Hsu, Scott C.; Thio, Yong C. Francis

2018-02-02

Spherically imploding plasma liners, formed by merging hypersonic plasma jets, are a proposed standoff driver to compress magnetized target plasmas to fusion conditions (Hsu et al. in IEEE Trans Plasma Sci 40:1287, 2012). Here, in this paper, the parameter space and physics criteria are identified for a subscale, plasma-liner-formation experiment to provide data, e.g., on liner ram-pressure scaling and uniformity, that are relevant for addressing scientific issues of full-scale plasma liners required to achieve fusion conditions. Lastly, based on these criteria, we quantitatively estimate the minimum liner kinetic energy and mass needed, which informed the design of a subscale plasmamore » liner experiment now under development.« less

Physics Criteria for a Subscale Plasma Liner Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, Scott C.; Thio, Yong C. Francis

Spherically imploding plasma liners, formed by merging hypersonic plasma jets, are a proposed standoff driver to compress magnetized target plasmas to fusion conditions (Hsu et al. in IEEE Trans Plasma Sci 40:1287, 2012). Here, in this paper, the parameter space and physics criteria are identified for a subscale, plasma-liner-formation experiment to provide data, e.g., on liner ram-pressure scaling and uniformity, that are relevant for addressing scientific issues of full-scale plasma liners required to achieve fusion conditions. Lastly, based on these criteria, we quantitatively estimate the minimum liner kinetic energy and mass needed, which informed the design of a subscale plasmamore » liner experiment now under development.« less

Using the tritium plasma experiment to evaluate ITER PFC safety

NASA Astrophysics Data System (ADS)

Longhurst, Glen R.; Anderl, Robert A.; Bartlit, John R.; Causey, Rion A.; Haines, John R.

1993-06-01

The Tritium Plasma Experiment was assembled at Sandia National Laboratories, Livermore and is being moved to the Tritium Systems Test Assembly facility at Los Alamos National Laboratory to investigate interactions between dense plasmas at low energies and plasma-facing component materials. This apparatus has the unique capabilty of replicating plasma conditions in a tokamak divertor with particle flux densities of 2 × 1023 ions/m2.s and a plasma temperature of about 15 eV using a plasma that includes tritium. An experimental program has been initiated using the Tritium Plasma Experiment to examine safety issues related to tritium in plasma-facing components, particularly the ITER divertor. Those issues include tritium retention and release characteristics, tritium permeation rates and transient times to coolant streams, surface modification and erosion by the plasma, the effects of thermal loads and cycling, and particulate production. An industrial consortium led by McDonnell Douglas will design and fabricate the test fixtures.

Plasma MRI Experiments at UW-Madison

NASA Astrophysics Data System (ADS)

Flanagan, K.; Clark, M.; Desangles, V.; Siller, R.; Wallace, J.; Weisberg, D.; Forest, C. B.

2015-11-01

Experiments for driving Keplerian-like flow profiles on both the Plasma Couette Experiment Upgrade (PCX-U) and the Wisconsin Plasma Astrophysics Laboratory (WiPAL) user facility are described. Instead of driving flow at the boundaries, as is typical in many liquid metal Couette experiments, a global drive is implemented. A large radial current is drawn across a small axial field generating torque across the whole profile. This global electrically driven flow is capable of producing profiles similar to Keplerian flow. PCX-U has been purposely constructed for MRI experiments, while similar experiments on the WiPAL device show the versatility of the user facility and provide a larger plasma volume. Numerical calculations show the predicted parameter spaces for exciting the MRI in these plasmas and the equilibrium flow profiles expected. In both devices, relevant MRI parameters appear to be within reach of typical operating characteristics.

Drift kinetic effects on plasma response in high beta spherical tokamak experiments

NASA Astrophysics Data System (ADS)

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.; Liu, Yueqiang; Kaye, Stanley M.; Gerhardt, Stefan

2018-01-01

The high β plasma response to rotating n=1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit (Troyon et al 1984 Plasma Phys. Control. Fusion 26 209). Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppresses the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. The complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.

PREFACE: 12th High-Tech Plasma Processes Conference (HTPP-12)

NASA Astrophysics Data System (ADS)

Gleizes, Alain; Ghedini, Emanuele; Gherardi, Matteo; Sanibondi, Paolo; Dilecce, Giorgio

2012-12-01

The High-Tech Plasma Processes - 12th European Plasma Conference (HTPP-12) was held in Bologna (Italy) on 24-29 June 2012. The conference series started in 1990 as a thermal plasma conference and gradually expanded to include other topic fields as well. Now the High-Tech Plasma Processes - European Plasma Conference (HTPP) is a bi-annual international conference based in Europe with topics encompassing the whole area of plasma processing science. The aim of the conference is to bring different scientific communities together, facilitate the contacts between science, technology and industry and provide a platform for the exploration of both fundamental topics and new applications of plasmas. Thanks to the efforts of the conference chairman, Professor Vittorio Colombo and of the co-chair, Professor Piero Favia, a well balanced participation from both the communities of thermal and nonthermal plasma researchers was achieved; this resulted in just about 196 attendees from 39 countries, with 8 plenary and 15 invited talks, plus 50 oral and 140 poster contributions. This volume of Journal of Physics: Conference Series gathers papers from regular contributions of HTPP-12; each contribution submitted for publication has been peer reviewed and the Editors are very grateful to the referees for their careful support in improving the original manuscripts. In the end, 39 manuscripts were accepted for publication, covering different topics of plasma processing science: from plasma fundamentals and modelling to source design and process diagnostics, from nanomaterial synthesis to surface modification, from waste treatment to plasma applications in a liquid environment. It is an honour to present this volume of Journal of Physics: Conference Series and we deeply thank the authors for their enthusiastic and high-grade contribution. Finally, we would like to thank the conference chairmen, the members of the steering committee, the international scientific committee, the local organizing committee, the organizing secretariat and the financial support from the conference sponsors that allowed the success of HTPP-12. The Editors of the HTPP 12 Proceedings Professor Alain Gleizes (head of the ISC) Dr Emanuele Ghedini Dr Matteo Gherardi Dr Paolo Sanibondi Dr Giorgio Dilecce Bologna, 30 October 2012

Transformative Pulsed Power Science and Technology

DTIC Science & Technology

2014-12-16

Lin, D. Singleton, J. Sanders, A. Kuthi and M.A. Gundersen, “Experimental study of pulsed corona discharge in air at high pressures”, 65th Annual...Kastner, E. Gutmark, and M. A. Gundersen. “Surface Streamer Discharge for Plasma Flow Control Using Nanosecond Pulsed Power.” Plasma Sciences, IEEE... discharge in atmospheric pressure fuel/air mixtures”, J. Phys. D: Appl. Phys. 45 495401 (2012). 28. S. J. Pendleton, S. Bowman, C. Carter, M. A. Gundersen

Update on Development of the Potassium-Argon Laser Experiment (KArLE) Instrument for In Situ Geochronology

NASA Technical Reports Server (NTRS)

Cohen, Barbara A.; Li, Z.-H.; Miller, J. S.; Brinckerhoff, W. B.; Clegg, S. M.; Mahaffy, P. R.; Swindle, T. D.; Wiens, R. C.

2013-01-01

Absolute dating of planetary samples is an essential tool to establish the chronology of geological events, including crystallization history, magmatic evolution, and alteration. We are addressing this challenge by developing the Potassium (K) -- Argon Laser Experiment (KArLE), building on previous work to develop a K-Ar in situ instrument. KArLE ablates a rock sample, determines the K in the plasma state using laser-induced breakdown spectroscopy (LIBS), measures the liberated Ar using quadrupole mass spectrometry (QMS), and relates the two by the volume of the ablated pit using laser confocal microscopy (LCM). Our goal is for the KArLE instrument to be capable of determining the age of several kinds of planetary samples to address a wide range of geochronolgy problems in planetary science.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

2008-08-01

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

Physics of Tokamak Plasma Start-up

NASA Astrophysics Data System (ADS)

Mueller, Dennis

2012-10-01

This tutorial describes and reviews the state-of-art in tokamak plasma start-up and its importance to next step devices such as ITER, a Fusion Nuclear Science Facility and a Tokamak/ST demo. Tokamak plasma start-up includes breakdown of the initial gas, ramp-up of the plasma current to its final value and the control of plasma parameters during those phases. Tokamaks rely on an inductive component, typically a central solenoid, which has enabled attainment of high performance levels that has enabled the construction of the ITER device. Optimizing the inductive start-up phase continues to be an area of active research, especially in regards to achieving ITER scenarios. A new generation of superconducting tokamaks, EAST and KSTAR, experiments on DIII-D and operation with JET's ITER-like wall are contributing towards this effort. Inductive start-up relies on transformer action to generate a toroidal loop voltage and successful start-up is determined by gas breakdown, avalanche physics and plasma-wall interaction. The goal of achieving steady-sate tokamak operation has motivated interest in other methods for start-up that do not rely on the central solenoid. These include Coaxial Helicity Injection, outer poloidal field coil start-up, and point source helicity injection, which have achieved 200, 150 and 100 kA respectively of toroidal current on closed flux surfaces. Other methods including merging reconnection startup and Electron Bernstein Wave (EBW) plasma start-up are being studied on various devices. EBW start-up generates a directed electron channel due to wave particle interaction physics while the other methods mentioned rely on magnetic helicity injection and magnetic reconnection which are being modeled and understood using NIMROD code simulations.

How can laboratory plasma experiments contribute to space and &astrophysics?

NASA Astrophysics Data System (ADS)

Yamada, M.

Plasma physics plays key role in a wide range of phenomena in the universe, from laboratory plasmas to the magnetosphere, the solar corona, and to the tenuous interstellar and intergalactic gas. Despite the huge difference in physical scales, there are striking similarities in plasma behavior of laboratory and space plasmas. Similar plasma physics problems have been investigated independently by both laboratory plasma physicists and astrophysicists. Since 1991, cross fertilization has been increased among laboratory plasma physicists and space physicists through meeting such as IPELS [Interrelationship between Plasma Experiments in the Laboratory and Space] meeting. The advances in laboratory plasma physics, along with the recent surge of astronomical data from satellites, make this moment ripe for research collaboration to further advance plasma physics and to obtain new understanding of key space and astrophysical phenomena. The recent NRC review of astronomy and astrophysics notes the benefit that can accrue from stronger connection to plasma physics. The present talk discusses how laboratory plasma studies can contribute to the fundamental understandings of the space and astrophysical phenomena by covering common key physics topics such as magnetic reconnection, dynamos, angular momentum transport, ion heating, and magnetic self-organization. In particular, it has recently been recognized that "physics -issue- dedicated" laboratory experiments can contribute significantly to the understanding of the fundamental physics for space-astrophysical phenomena since they can create fundamental physics processes in controlled manner and provide well-correlated plasma parameters at multiple plasma locations simultaneously. Such dedicated experiments not only can bring about better understanding of the fundamental physics processes but also can lead to findings of new physics principles as well as new ideas for fusion plasma confinement. Several dedicated experiments have provided the fundamental physics data for magnetic reconnection [1]. Linear plasma devices have been utilized to investigate Whistler waves and Alfven wave phenomena [2,3]. A rotating gallium disk experiment has been initiated to study magneto-rotational instability [4]. This talk also presents the most recent progress of these dedicated laboratory plasma research. 1. M. Yamada et al., Phys. Plasmas 4, 1936, (1997) 2. R. Stenzel, Phys. Rev. Lett. 65, 3001 (1991) 3. W. Gekelman et al, Plasma Phys. Contr. Fusion, v42, B15-B26, Suppl.12B (2000) 4. H. Ji, J. Goodman, A. Kageyama Mon. Not. R. Astron. Soc. 325, L1- (2001)

Application of Plasma Waveguides to High Energy Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 analysismore » 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.« less

Time-Space Position of Warm Dense Matter in Laser Plasma Interaction Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, L F; Uschmann, I; Forster, E

2006-09-25

Laser plasma interaction experiments have been perform performed using an fs Titanium Sapphire laser. Plasmas have been generated from planar PMMA targets using single laser pulses with 3.3 mJ pulse energy, 50 fs pulse duration at 800 nm wavelength. Electron density distributions of the plasmas in different delay times have been characterized by means of Nomarski Interferometry. Experimental data were cautiously compared with relevant 1D numerical simulation. Finally these results provide a first experience of searching for the time-space position of the so-called warm dense plasma in an ultra fast laser target interaction process. These experiments aim to prepare nearmore » solid-density plasmas for Thomson scattering experiments using the short wavelength free-electron laser FLASH, DESY Hamburg.« less

Waves in the middle and upper atmosphere of Mars as seen by the Radio Science Experiment MaRS on Mars Express

NASA Astrophysics Data System (ADS)

Tellmann, S.; Paetzold, M.; Häusler, B.; Hinson, D. P.; Peter, K.; Tyler, G. L.

2017-12-01

Atmospheric waves play a crucial role in the Martian atmosphere. They are responsible for the redistribution of momentum, energy and dust and for the coupling of the different atmospheric regions on Mars. Almost all kinds of waves have been observed in the lower atmosphere (e.g. stationary and transient waves, baroclinic waves as well as migrating and non-migrating thermal tides, gravity waves, etc...). Atmospheric waves are also known to exist in the middle atmosphere of Mars ( 70-120 km, e.g. by the SPICAM instrument on Mars Express). In the thermosphere, thermal tides have been observed e.g. by radio occultation or accelerometer measurements on MGS. Recently, the NGIMS instrument on MAVEN reported gravity waves in the thermosphere of Mars. Radio Science profiles from the Mars Express Radio Science experiment MaRS on Mars Express can analyse the temperature, pressure and neutral number density profiles in the lower atmosphere (from a few hundred metres above the surface up to 40-50 km) and electron density profiles in the ionosphere of Mars. Wavelike structures have been detected below the main ionospheric layers (M1 & M2) and in the topside of the ionosphere. The two coherent frequencies of the MaRS experiment allow to discriminate between plasma density fluctuations in the ionosphere and Doppler related frequency shifts caused by spacecraft movement. A careful analysis of the observed electron density fluctuations in combination with sensitivity studies of the radio occultation technique will be used to classify the observed fluctuations. The MaRS experiment is funded by DLR under grant 50QM1401.

Waves in the middle and upper atmosphere of Mars as seen by the Radio Science Experiment MaRS on Mars Express

NASA Astrophysics Data System (ADS)

Tellmann, Silvia Anna; Paetzold, Martin; Häusler, Bernd; Hinson, David P.; Peter, Kerstin; Tyler, G. Leonard

2017-10-01

Atmospheric waves play a crucial role for the dynamics in the Martian atmosphere. They are responsible for the redistribution of momentum, energy and dust and the coupling of the different atmospheric regions on Mars.Almost all kinds of waves have been observed in the lower atmosphere (e.g. stationary and transient waves, baroclinic waves as well as migrating and non-migrating thermal tides, and gravity waves). Atmospheric waves are also known to exist in the middle atmosphere of Mars (~70-120 km, e.g. by the SPICAM instrument on Mars Express). In the thermosphere, thermal tides have been observed e.g. by radio occultation or accelerometer measurements on MGS. Recently, the NGIMS instrument on MAVEN reported gravity waves in the thermosphere of Mars.Radio Science profiles from the Mars Express Radio Science experiment MaRS on Mars Express can analyse the temperature, pressure and neutral number density profiles in the lower atmosphere (from a few hundred metres above the surface up to ~ 40-50 km) and electron density profiles in the ionosphere of Mars.Wavelike structures have been detected below the main ionospheric layers (M1 & M2) and in the topside of the ionosphere. The two coherent frequencies of the MaRS experiment allow to discriminate between plasma density fluctuations in the ionosphere and Doppler related frequency shifts caused by spacecraft movement.A careful analysis of the observed electron density fluctuations in combination with sensitivity studies of the radio occultation technique will be used to classify the observed fluctuations.The MaRS experiment is funded by DLR under grant 50QM1401.

Contoured-gap coaxial guns for imploding plasma liner experiments

NASA Astrophysics Data System (ADS)

Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

2014-10-01

Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

View of the Columbia's remote manipulator system

NASA Image and Video Library

1982-03-30

STS003-09-444 (22-30 March 1982) --- The darkness of space provides the backdrop for this scene of the plasma diagnostics package (PDR) experiment in the grasp of the end effector or ?hand? of the remote manipulator system (RMS) arm, and other components of the Office of Space Sciences (OSS-1) package in the aft section of the Columbia?s cargo hold. The PDP is a compact, comprehensive assembly of electromagnetic and particle sensors that will be used to study the interaction of the orbiter with its surrounding environment; to test the capabilities of the shuttle?s remote manipulator system; and to carry out experiments in conjunction with the fast pulse electron generator of the vehicle charging and potential experiment, another experiment on the OSS-1 payload pallet. This photograph was exposed with a 70mm handheld camera by the astronaut crew of STS-3, with a handheld camera aimed through the flight deck?s aft window. Photo credit: NASA

Drift kinetic effects on the plasma response in high beta spherical tokamak experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.

The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppressesmore » the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.« less

Drift kinetic effects on the plasma response in high beta spherical tokamak experiments

DOE PAGES

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.; ...

2017-09-21

The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppressesmore » the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.« less

High-current plasma contactor neutralizer system

NASA Technical Reports Server (NTRS)

Beattie, J. R.; Williamson, W. S.; Matossian, J. N.; Vourgourakis, E. J.; Burch, J. L.

1989-01-01

A plasma-contactor neutralizer system is described, for the stabilizing the Orbiter's potential during flights of the Atmospheric Laboratory for Applications and Science missions. The plasma contactor neutralizer will include a Xe plasma source that can provide steady-state ion-emission currents of up to 1.5 A. The Orbiter's potential will be maintained near that of the surrounding space plasma during electron-beam accelerator firings through a combination of ion emission from the Xe plasma source and electron collection from the ambient space plasma. Configuration diagrams and block diagrams are presented along with the performance characteristics of the system.

RF Antenna Design for a Helicon Plasma Source

NASA Astrophysics Data System (ADS)

Godden, Katarina; Stassel, Brendan; Warta, Daniel; Yep, Isaac; Hicks, Nathaniel; Munk, Jens

2017-10-01

A helicon plasma source is under development for the new Plasma Science and Engineering Laboratory at the University of Alaska Anchorage. The helicon source is of a type comprising Pyrex and stainless steel cylindrical sections, joined to an ultrahigh vacuum chamber. A radio frequency (RF) helical antenna surrounds the Pyrex chamber, as well as DC solenoidal magnetic field coils. This presentation focuses on the design of the RF helical antenna and RF matching network, such that helicon wave power is coupled to argon plasma with minimal reflected power to the RF amplifier. The amplifier output is selectable between 2-30 MHz, with forward c.w. power up to 1.5 kW. Details and computer simulation of the antenna geometry, materials, and power matching will be presented, as well as the matching network of RF transmission line, tuning capacitors, and cooling system. An initial computational study of power coupling to the plasma will also be described. Supported by U.S. NSF/DOE Partnership in Basic Plasma Science and Engineering Grant PHY-1619615, by the Alaska Space Grant Program, and by UAA Innovate 2017.

Spectroscopic Study of a Pulsed High-Energy Plasma Deflagration Accelerator

NASA Astrophysics Data System (ADS)

Loebner, Keith; Underwood, Thomas; Mouratidis, Theodore; Cappelli, Mark

2015-11-01

Observations of broadened Balmer lines emitted by a highly-ionized transient plasma jet are presented. A gated CCD camera coupled to a high-resolution spectrometer is used to obtain chord-averaged broadening data for a complete cross section of the plasma jet, and the data is Abel inverted to derive the radial plasma density distribution. This measurement is performed over narrow gate widths and at multiple axial positions to provide high spatial and temporal resolution. A streak camera coupled to a spectrometer is used to obtain continuous-time broadening data over the entire duration of the discharge event (10-50 microseconds). Analyses of discharge characteristics and comparisons with previous work are discussed. This work is supported by the U.S. Department of Energy Stewardship Science Academic Program, as well as the National Defense Science Engineering Graduate Fellowship.

ADX: a high field, high power density, advanced divertor and RF tokamak

NASA Astrophysics Data System (ADS)

LaBombard, B.; Marmar, E.; Irby, J.; Terry, J. L.; Vieira, R.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; Baek, S.; Beck, W.; Bonoli, P.; Brunner, D.; Doody, J.; Ellis, R.; Ernst, D.; Fiore, C.; Freidberg, J. P.; Golfinopoulos, T.; Granetz, R.; Greenwald, M.; Hartwig, Z. S.; Hubbard, A.; Hughes, J. W.; Hutchinson, I. H.; Kessel, C.; Kotschenreuther, M.; Leccacorvi, R.; Lin, Y.; Lipschultz, B.; Mahajan, S.; Minervini, J.; Mumgaard, R.; Nygren, R.; Parker, R.; Poli, F.; Porkolab, M.; Reinke, M. L.; Rice, J.; Rognlien, T.; Rowan, W.; Shiraiwa, S.; Terry, D.; Theiler, C.; Titus, P.; Umansky, M.; Valanju, P.; Walk, J.; White, A.; Wilson, J. R.; Wright, G.; Zweben, S. J.

2015-05-01

The MIT Plasma Science and Fusion Center and collaborators are proposing a high-performance Advanced Divertor and RF tokamak eXperiment (ADX)—a tokamak specifically designed to address critical gaps in the world fusion research programme on the pathway to next-step devices: fusion nuclear science facility (FNSF), fusion pilot plant (FPP) and/or demonstration power plant (DEMO). This high-field (⩾6.5 T, 1.5 MA), high power density facility (P/S ˜ 1.5 MW m-2) will test innovative divertor ideas, including an ‘X-point target divertor’ concept, at the required performance parameters—reactor-level boundary plasma pressures, magnetic field strengths and parallel heat flux densities entering into the divertor region—while simultaneously producing high-performance core plasma conditions that are prototypical of a reactor: equilibrated and strongly coupled electrons and ions, regimes with low or no torque, and no fuelling from external heating and current drive systems. Equally important, the experimental platform will test innovative concepts for lower hybrid current drive and ion cyclotron range of frequency actuators with the unprecedented ability to deploy launch structures both on the low-magnetic-field side and the high-magnetic-field side—the latter being a location where energetic plasma-material interactions can be controlled and favourable RF wave physics leads to efficient current drive, current profile control, heating and flow drive. This triple combination—advanced divertors, advanced RF actuators, reactor-prototypical core plasma conditions—will enable ADX to explore enhanced core confinement physics, such as made possible by reversed central shear, using only the types of external drive systems that are considered viable for a fusion power plant. Such an integrated demonstration of high-performance core-divertor operation with steady-state sustainment would pave the way towards an attractive pilot plant, as envisioned in the ARC concept (affordable, robust, compact) (Sorbom et al 2015 Fusion Eng. Des. submitted (arXiv:1409.3540)) that makes use of high-temperature superconductor technology—a high-field (9.25 T) tokamak the size of the Joint European Torus that produces 270 MW of net electricity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Virginia Finley

The results of the 1999 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 1999. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program ismore » to create innovations to make fusion power a practical reality--an alternative energy source. 1999 marked the first year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. The 1999 performance of the Princeton Plasma Physics Laboratory was rated ''outstanding'' by the U.S. Department of Energy in the Laboratory Appraisal report issued early in 2000. The report cited the Laboratory's consistently excellent scientific and technological achievements, its successful management practices, and included high marks in a host of other areas including environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.« less

Complex Plasma Physics and Rising Above the Gathering Storm

NASA Astrophysics Data System (ADS)

Hyde, Truell

2008-11-01

Research in complex plasma is prevalent across a variety of regimes ranging from the majority of plasma processing environments to many astrophysical settings. Dust particles suspended within such plasmas acquire a charge from collisions with electrons and ions in the plasma. Depending upon the ratio of their interparticle potential energy to their average kinetic energy, once charged these particles can form a gaseous, liquid or crystalline structure with short to longer range ordering. The field of complex plasmas thus offers research opportunities across a wide range of academic disciplines including physics, chemistry, biology, mathematics, electrical engineering and nanoscience. The field of complex plasmas also offers unique educational research opportunities for combating many of the issues raised in Rising Above the Gathering Storm, recently published by the National Academies Press. CASPER's Educational Outreach programs, supported by the National Science Foundation, the Department of Education and the Department of Labor takes advantage of these opportunities through a variety of avenues including a REU / RET program, a High School Scholars Program, integrated curriculum development and the CASPER Physics Circus. Together, these programs impact thousands of students and parents while providing K-12 teachers with curriculum, supporting hands-on material and support for introducing plasma and basic physical science concepts into the classroom. Both research results and educational outreach concepts from the above will be discussed.

Thermodynamic and Transport Properties of Real Air Plasma in Wide Range of Temperature and Pressure

NASA Astrophysics Data System (ADS)

Wang, Chunlin; Wu, Yi; Chen, Zhexin; Yang, Fei; Feng, Ying; Rong, Mingzhe; Zhang, Hantian

2016-07-01

Air plasma has been widely applied in industrial manufacture. In this paper, both dry and humid air plasmas' thermodynamic and transport properties are calculated in temperature 300-100000 K and pressure 0.1-100 atm. To build a more precise model of real air plasma, over 70 species are considered for composition. Two different methods, the Gibbs free energy minimization method and the mass action law method, are used to determinate the composition of the air plasma in a different temperature range. For the transport coefficients, the simplified Chapman-Enskog method developed by Devoto has been applied using the most recent collision integrals. It is found that the presence of CO2 has almost no effect on the properties of air plasma. The influence of H2O can be ignored except in low pressure air plasma, in which the saturated vapor pressure is relatively high. The results will serve as credible inputs for computational simulation of air plasma. supported by the National Key Basic Research Program of China (973 Program)(No. 2015CB251002), National Natural Science Foundation of China (Nos. 51521065, 51577145), the Science and Technology Project Funds of the Grid State Corporation (SGTYHT/13-JS-177), the Fundamental Research Funds for the Central Universities, and State Grid Corporation Project (GY71-14-004)

The effects of increasing doses of 2 preparations of long-acting insulin on short-term plasma profiles of glucose and insulin in lactating dairy cows.

PubMed

Winkelman, L A; Overton, T R

2012-12-01

Two experiments were conducted to investigate effects of administering increasing doses of 2 different preparations of long-acting insulin on the 24-h profiles of plasma glucose and insulin concentrations in mid lactation dairy cows. The 2 separately analyzed experiments investigated the effects administering either Humulin N (H), a neutral protamine Hagedorn insulin, or insulin glargine (Lantus, L), an insulin analog, at doses of 0 (control), 0.1, 0.2, and 0.4 IU/kg of body weight in a randomized complete block design. Sixteen cows (237±11 d in milk for H; 213±10 d in milk for L; mean ± SD) were used for each insulin preparation, resulting in n=4 for each dose within insulin preparation. Cows were fitted with a single jugular catheter on the day before the study. On the day of the study, cows were given treatments by subcutaneous injection of either sterile water or the designated insulin type and dose. Blood samples were taken hourly from the jugular catheter. Subcutaneous injection of both H and L resulted in linear decreases in plasma glucose concentrations, increased area under the curve, and decreased nadir for plasma glucose following administration of the insulin preparations. Plasma insulin concentration linearly increased with increasing dose of H. Though elevated concentrations of insulin were measurable in cows treated with H, they were not measurable in cows treated with L. Attempts to measure overall insulin concentrations and metabolites of L by a commercially available ELISA and a commercially available RIA kit were not successful and did not retrieve values that we felt truly represented the amount of insulin activity exhibited during this treatment. Both long-acting insulin preparations elicited insulin-like activity in lactating dairy cows, as evidenced by reduced plasma glucose concentrations. Given these results, the potential exists to use both H and L to study the effects of insulin in mid lactation dairy cows without the confounding effect of severe hypoglycemia (<20 mg/dL) or concurrent provision of glucose during treatment. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Laser-plasmas in the relativistic-transparency regime: Science and applications

NASA Astrophysics Data System (ADS)

Fernández, Juan C.; Cort Gautier, D.; Huang, Chengkung; Palaniyappan, Sasikumar; Albright, Brian J.; Bang, Woosuk; Dyer, Gilliss; Favalli, Andrea; Hunter, James F.; Mendez, Jacob; Roth, Markus; Swinhoe, Martyn; Bradley, Paul A.; Deppert, Oliver; Espy, Michelle; Falk, Katerina; Guler, Nevzat; Hamilton, Christopher; Hegelich, Bjorn Manuel; Henzlova, Daniela; Ianakiev, Kiril D.; Iliev, Metodi; Johnson, Randall P.; Kleinschmidt, Annika; Losko, Adrian S.; McCary, Edward; Mocko, Michal; Nelson, Ronald O.; Roycroft, Rebecca; Santiago Cordoba, Miguel A.; Schanz, Victor A.; Schaumann, Gabriel; Schmidt, Derek W.; Sefkow, Adam; Shimada, Tsutomu; Taddeucci, Terry N.; Tebartz, Alexandra; Vogel, Sven C.; Vold, Erik; Wurden, Glen A.; Yin, Lin

2017-05-01

Laser-plasma interactions in the novel regime of relativistically induced transparency (RIT) have been harnessed to generate intense ion beams efficiently with average energies exceeding 10 MeV/nucleon (>100 MeV for protons) at "table-top" scales in experiments at the LANL Trident Laser. By further optimization of the laser and target, the RIT regime has been extended into a self-organized plasma mode. This mode yields an ion beam with much narrower energy spread while maintaining high ion energy and conversion efficiency. This mode involves self-generation of persistent high magnetic fields (˜104 T, according to particle-in-cell simulations of the experiments) at the rear-side of the plasma. These magnetic fields trap the laser-heated multi-MeV electrons, which generate a high localized electrostatic field (˜0.1 T V/m). After the laser exits the plasma, this electric field acts on a highly structured ion-beam distribution in phase space to reduce the energy spread, thus separating acceleration and energy-spread reduction. Thus, ion beams with narrow energy peaks at up to 18 MeV/nucleon are generated reproducibly with high efficiency (≈5%). The experimental demonstration has been done with 0.12 PW, high-contrast, 0.6 ps Gaussian 1.053 μm laser pulses irradiating planar foils up to 250 nm thick at 2-8 × 1020 W/cm2. These ion beams with co-propagating electrons have been used on Trident for uniform volumetric isochoric heating to generate and study warm-dense matter at high densities. These beam plasmas have been directed also at a thick Ta disk to generate a directed, intense point-like Bremsstrahlung source of photons peaked at ˜2 MeV and used it for point projection radiography of thick high density objects. In addition, prior work on the intense neutron beam driven by an intense deuterium beam generated in the RIT regime has been extended. Neutron spectral control by means of a flexible converter-disk design has been demonstrated, and the neutron beam has been used for point-projection imaging of thick objects. The plans and prospects for further improvements and applications are also discussed.

Laser-plasmas in the relativistic-transparency regime: science and applications

DOE PAGES

Fernandez, Juan Carlos; Gautier, Donald Cort; Huang, Chengkun; ...

2017-05-30

Laser-plasma interactions in the novel regime of relativistically induced transparency (RIT) have been harnessed to generate intense ion beams efficiently with average energies exceeding 10 MeV/nucleon (>100 MeV for protons) at “table-top” scales in experiments at the LANL Trident Laser. By further optimization of the laser and target, the RIT regime has been extended into a self-organized plasma mode. This mode yields an ion beam with much narrower energy spread while maintaining high ion energy and conversion efficiency. This mode involves self-generation of persistent high magnetic fields (~10 4 T, according to particle-in-cell simulations of the experiments) at the rear-sidemore » of the plasma. These magnetic fields trap the laser-heated multi-MeV electrons, which generate a high localized electrostatic field (~0.1 TV/m). After the laser exits the plasma, this electric field acts on a highly structured ion-beam distribution in phase space to reduce the energy spread, thus separating acceleration and energy-spread reduction. Thus, ion beams with narrow energy peaks at up to 18 MeV/nucleon are generated reproducibly with high efficiency (≈5%). The experimental demonstration has been done with 0.12 PW, high-contrast, 0.6 ps Gaussian 1.053 μm laser pulses irradiating planar foils up to 250 nm thick at 2–8 × 10 20 W/cm 2. These ion beams with co-propagating electrons have been used on Trident for uniform volumetric isochoric heating to generate and study warm-dense matter at high densities. These beam plasmas have been directed also at a thick Ta disk to generate a directed, intense point-like Bremsstrahlung source of photons peaked at ~2 MeV and used it for point projection radiography of thick high density objects. In addition, prior work on the intense neutron beam driven by an intense deuterium beam generated in the RIT regime has been extended. Neutron spectral control by means of a flexible converter-disk design has been demonstrated, and the neutron beam has been used for point-projection imaging of thick objects. Finally, we discuss the plans and prospects for further improvements and applications.« less

Platelet-Rich Plasma in the Animal Long-Bone Model: An Analysis of Basic Science Evidence.

PubMed

Gianakos, Arianna; Zambrana, Lester; Savage-Elliott, Ian; Lane, Joseph M; Kennedy, John G

2015-12-01

Platelet-rich plasma (PRP) has been suggested as an adjunct to aid in long-bone healing. The purpose of this study was to systematically review the basic science in vivo evidence for the use of PRP in the treatment of bone pathology. The PubMed/MEDLINE and EMBASE databases were screened using the following search criteria: "(Platelet-rich plasma OR PRP OR autologous conditioned plasma OR ACP) AND (bone OR osteocytes OR osteogenesis OR nonunion OR delayed union)." Studies were included if they fulfilled the following criteria: (1) studied the effect of PRP or a similar concentrated platelet product, defined as a blood product with platelet concentration elevated to higher than baseline; (2) established a control with which to compare PRP; (3) were published in a peer-reviewed journal; and (4) looked specifically at animal long-bone models. All review articles and clinical studies, including randomized controlled trials and case series, were excluded from the review. Studies examining the effects of PRP on bones of animals with confounding pathology were excluded. In studies that contained additional treatment variables, only the portion of the experiment that compared PRP directly with the control were evaluated. Data were then extracted with a standardized table. The search yielded 29 articles for inclusion. Seventy-two percent of the studies reported platelet concentrations. Eighty-nine percent of studies reported significant improvement in earlier bone healing on histologic/histomorphometric assessment. One hundred percent showed significant increase in bone formation on radiographs in the PRP group. Eighty percent of studies reported a significant increase in bone area on microcomputed tomography. One hundred percent of studies showed a higher torsional stiffness for the PRP-treated defects. In the in vivo studies evaluated, PRP confers several beneficial effects on animal long-bone models. Proof of concept for PRP as a biologic adjunct in long-bone models has been determined. Copyright 2015, SLACK Incorporated.

Fusion Sciences Education Outreach in the Middle Schools, an Unplanned Case Study

NASA Astrophysics Data System (ADS)

Danielson, C. A.

1997-11-01

Before bringing a class to General Atomics (GA) for the DIII--D educational tour, the teacher is provided with pre-tour materials which include a videotape, curriculum notebook and fusion poster. These materials are used in the classroom to familiarize students with fusion concepts before the tour. This presentation will focus on the results of projects of 7th grade students of Chula Vista Junior High School (a magnet school for performing arts with a majority of Hispanic students). The assignment given by Physics Teacher Caryn Hoffman to her students prior to the tour was to focus on one or two of the DIII--D tour guides, ask questions relating to their careers in science and then prepare a presentation based on their interviews and their tour experience. The completed projects were very diverse -- calendars, comic strips, newspapers, plays, and board games were some of the media the students used. Tour guides selected by the students ranged from physicists, designers and computer support personnel. Project results reflected a surprisingly good understanding of fusion science concepts. Subsequent classroom interviews with the students demonstrated an overall increase in science interest and a specific interest in plasma and fusion research.

Teaching Heliophysics Science to Undergraduates in an Engineering Context

NASA Astrophysics Data System (ADS)

Baker, J. B.; Sweeney, D. G.; Ruohoniemi, J.

2013-12-01

In recent years, space research at Virginia Tech has experienced rapid growth since the initiation of the Center for Space Science and Engineering Research (Space@VT) during the summer of 2007. The Space@VT center resides in the College of Engineering and currently comprises approximately 30-40 faculty and students. Space@VT research encompasses a wide spectrum of science and engineering activities including: magnetosphere-ionosphere data analysis; ground- and space-based instrument development; spacecraft design and environmental interactions; and numerical space plasma simulations. In this presentation, we describe how Space@VT research is being integrated into the Virginia Tech undergraduate engineering curriculum via classroom instruction and hands-on group project work. In particular, we describe our experiences teaching a new sophomore course titled 'Exploration of the Space Environment' which covers a broad range of scientific, engineering, and societal aspects associated with the exploration and technological exploitation of space. Topics covered include: science of the space environment; space weather hazards and societal impacts; elementary orbital mechanics and rocket propulsion; spacecraft engineering subsystems; and applications of space-based technologies. We also describe a high-altitude weather balloon project which has been offered as a 'hands-on' option for fulfilling the course project requirements of the course.

Preliminary Development of a Computational Model of a Dielectric Barrier Discharge

DTIC Science & Technology

2004-12-01

Gerhard Pietsch . "Microdischarges in Air-Fed Ozonizers," Journal of Physics D: Applied Physics, Vol 24, 1991, pp 564-572. 14 Baldur Eliasson. "Modeling...Gibalov and Gerhard Pietsch . "Two-dimensional Modeling of the Dielectric Barrier Discharge in Air," Plasma Sources Science Technology, 1 (1992), pp. 166...Computer Modeling," IEEE Transactions on Plasma Science, 27 (1), February 1999, pp 36-37. 19 Valentin I Gibalov and Gerhard J. Pietsch . "The

Laboratory and Space Plasma Studies

NASA Astrophysics Data System (ADS)

Hyman, Ellis

1996-08-01

The work performed by Science Applications International Corporation (SAIC), encompasses a wide range of topics in experimental, computational, and analytical laboratory and space plasma physics. The accomplishments described in this report have been in support of the programs of the Laser Plasma Branch (Code 6730) and other segments of the Plasma Physics Division at the Naval Research Laboratory (NRL) and cover the period 27 September 1993 to August 1, 1996. SAIC's efforts have been supported by sub-contracts or consulting agreements with Pulse Sciences, Inc., Clark Richardson, and Biskup Consulting Engineers, Pharos Technical Enterprises, Plex Corporation, Cornell University, Stevens Institute of Technology, the University of Connecticut, Plasma Materials and Technologies, Inc., and GaSonics International, Inc. In the following discussions section we will describe each of the topics investigated and the results obtained. Much of the research work has resulted in journal publications and NRL Memorandum Reports in which the investigation is described in detail. These reports are included as Appendices to this Final Report.

The development and testing of the fast imaging plasma spectrometer and its application in the plasma environment at Mercury

NASA Astrophysics Data System (ADS)

Koehn, Patrick Leo

The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric particles, and pickup ions. Pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury should include a sensor that is able to determine the dynamical properties and composition of all three plasma components. The Fast Imaging Plasma Spectrometer (FIPS) is an instrument to measure the composition of these ion populations and their three-dimensional velocity distribution functions. It is lightweight, fast, and has a very large field of view, and these properties made possible its accommodation within the highly mass- constrained payload of MESSENGER (MErcury: Surface, Space ENvironment, GEochemistry, Ranging) mission, a Mercury orbiter. This work details the development cycle of FIPS, from concept to prototype testing. It begins with science studies of the magnetospheric and pickup ion environments of Mercury, using state-of-the-art computer simulations to produce static and quasi-dynamic magnetospheric systems. Predictions are made of the spatially variable plasma environment at Mercury, and the temporally varying magnetosphere-solar wind interaction is examined. Pickup ion studies provide insights to particle loss mechanisms and the nature of the radar-bright regions at the Hermean poles. These studies produce science requirements for successfully measuring this environment with an orbiting mass spectrometer. With these science requirements in mind, a concept for a new electrostatic analyzer is created. This concept is considered from a theoretical standpoint, and compared with other, similarly performing instruments, both of the past and currently in use. The development cycle continues with instrument simulation, which allows the design to be adjusted to fit within the science requirements of the mission. Finally, a prototype electrostatic is constructed and tested in a space- simulating vacuum chamber system. The results of these tests are compared with the simulation results, and ultimately shown to fit within the science requirements for the MESSENGER mission.

Plasma contactor research, 1989

NASA Technical Reports Server (NTRS)

Williams, John D.

1990-01-01

The characteristics of double layers observed by researchers investigating magnetospheric phenomena are contrasted to those observed in plasma contacting experiments. Experiments in the electron collection mode of the plasma contacting process were performed and the results confirm a simple model of this process for current levels ranging to 3 A. Experimental results were also obtained in a study of the process of electron emission from a hollow cathode plasma contactor. High energy ions are observed coming from the cathode in addition to the electrons and a phenomenological model that suggests a mechanism by which this could occur is presented. Experimental results showing the effects of the design parameters of the ambient plasma simulator on the plasma potential, electron temperature, electron density and plasma noise levels induced in plasma contacting experiments are presented. A preferred simulator design is selected on the basis of these results.

Isotope effects on L-H threshold and confinement in tokamak plasmas

NASA Astrophysics Data System (ADS)

Maggi, C. F.; Weisen, H.; Hillesheim, J. C.; Chankin, A.; Delabie, E.; Horvath, L.; Auriemma, F.; Carvalho, I. S.; Corrigan, G.; Flanagan, J.; Garzotti, L.; Keeling, D.; King, D.; Lerche, E.; Lorenzini, R.; Maslov, M.; Menmuir, S.; Saarelma, S.; Sips, A. C. C.; Solano, E. R.; Belonohy, E.; Casson, F. J.; Challis, C.; Giroud, C.; Parail, V.; Silva, C.; Valisa, M.; Contributors, JET

2018-01-01

The dependence of plasma transport and confinement on the main hydrogenic ion isotope mass is of fundamental importance for understanding turbulent transport and, therefore, for accurate extrapolations of confinement from present tokamak experiments, which typically use a single hydrogen isotope, to burning plasmas such as ITER, which will operate in deuterium-tritium mixtures. Knowledge of the dependence of plasma properties and edge transport barrier formation on main ion species is critical in view of the initial, low-activation phase of ITER operations in hydrogen or helium and of its implications on the subsequent operation in deuterium-tritium. The favourable scaling of global energy confinement time with isotope mass, which has been observed in many tokamak experiments, remains largely unexplained theoretically. Moreover, the mass scaling observed in experiments varies depending on the plasma edge conditions. In preparation for upcoming deuterium-tritium experiments in the JET tokamak with the ITER-like Be/W Wall (JET-ILW), a thorough experimental investigation of isotope effects in hydrogen, deuterium and tritium plasmas is being carried out, in order to provide stringent tests of plasma energy, particle and momentum transport models. Recent hydrogen and deuterium isotope experiments in JET-ILW on L-H power threshold, L-mode and H-mode confinement are reviewed and discussed in the context of past and more recent isotope experiments in tokamak plasmas, highlighting common elements as well as contrasting observations that have been reported. The experimental findings are discussed in the context of fundamental aspects of plasma transport models.

EDITORIAL: Invited review and topical lectures from the 13th International Congress on Plasma Physics

NASA Astrophysics Data System (ADS)

Zagorodny, A.; Kocherga, O.

2007-05-01

The 13th International Congress on Plasma Physics (ICPP 2006) was organized, on behalf of the International Advisory Committee of the ICPP series, by the National Academy of Sciences of Ukraine and the Bogolyubov Institute for Theoretical Physics (BITP) and held in Kiev, Ukraine, 22 26 May 2006. The Congress Program included the topics: fundamental problems of plasma physics; fusion plasmas; plasmas in astrophysics and space physics; plasmas in applications and technologies; complex plasmas. A total of 305 delegates from 30 countries took part in the Congress. The program included 9 invited review lectures, 32 invited topical and 313 contributed papers (60 of which were selected for oral presentation). The Congress Program was the responsibility of the International Program Committee: Anatoly Zagorodny (Chairman) Bogolyubov Institute for Theoretical Physics, Ukraine Olha Kocherga (Scientific Secretary) Bogolyubov Institute for Theoretical Physics, Ukraine Boris Breizman The University of Texas at Austin, USA Iver Cairns School of Physics, University of Sydney, Australia Tatiana Davydova Institute for Nuclear Research, Ukraine Tony Donne FOM-Institute for Plasma Physics, Rijnhuizen, The Netherlands Nikolai S Erokhin Space Research Institute of RAS, Russia Xavier Garbet CEA, France Valery Godyak OSRAM SYLVANIA, USA Katsumi Ida National Institute for Fusion Science, Japan Alexander Kingsep Russian Research Centre `Kurchatov Institute', Russia E P Kruglyakov Budker Institute of Nuclear Physics, Russia Gregor Morfill Max-Planck-Institut für extraterrestrische Physik, Germany Osamu Motojima National Institute for Fusion Science, Japan Jef Ongena ERM-KMS, Brussels and EFDA-JET, UK Konstantyn Shamrai Institute for Nuclear Research, Ukraine Raghvendra Singh Institute for Plasma Research, India Konstantyn Stepanov Kharkiv Institute of Physics and Technology, Ukraine Masayoshi Tanaka National Institute for Fusion Science, Japan Nodar Tsintsadze Physics Institute, Georgia The four-page texts of the contributed papers are presented as a CD, `ICPP 2006. Contributed Papers' which was distributed among the delegates. They are also available at the Congress website http://icpp2006.kiev.ua. A major part of the review and topical lectures is published in this special issue which has been sent to the Congress delegates. The papers were refereed to the usual high standard of the journal Plasma Physics and Controlled Fusion. The Guest Editors of the special issue are grateful to the Publishers for their cooperation. Recognizing the role of Professor Alexej Sitenko (12 February 1927 11 February 2002) in the initiation and organization of the International (Kiev) Conferences on Plasma Theory which, after having been combined with the International Congresses on Waves and Instabilities in Plasma in 1980, created the series of International Congresses on Plasma Physics, and taking into account the contribution of Professor Sitenko to the progress of plasma theory, the Program Committee decided to open ICPP 2006 with the Sitenko memorial lecture. This memorial lecture is available as supplementary data (PDF) at stacks.iop.org/PPCF/49/i=5A.

PREFACE: 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers

NASA Astrophysics Data System (ADS)

Takizuka, Tomonori

2008-07-01

This volume of Journal of Physics: Conference Series contains papers based on invited talks and contributed posters presented at the 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers. This meeting was held at the Tsukuba International Congress Center in Tsukuba, Japan, on 26-28 September 2007, and was organized jointly by the Japan Atomic Energy Agency and the University of Tsukuba. The previous ten meetings in this series were held in San Diego (USA) 1987, Gut Ising (Germany) 1989, Abingdon (UK) 1991, Naka (Japan) 1993, Princeton (USA) 1995, Kloster Seeon (Germany) 1997, Oxford (UK) 1999, Toki (Japan) 2001, San Diego (USA) 2003, and St Petersburg (Russia) 2005. The purpose of the eleventh meeting was to present and discuss new results on H-mode (edge transport barrier, ETB) and internal transport barrier, ITB, experiments, theory and modeling in magnetic fusion research. It was expected that contributions give new and improved insights into the physics mechanisms behind high confinement modes of H-mode and ITBs. Ultimately, this research should lead to improved projections for ITER. As has been the tradition at the recent meetings of this series, the program was subdivided into six topics. The topics selected for the eleventh meeting were: H-mode transition and the pedestal-width Dynamics in ETB: ELM threshold, non-linear evolution and suppression, etc Transport relations of various quantities including turbulence in plasmas with ITB: rotation physics is especially highlighted Transport barriers in non-axisymmetric magnetic fields Theory and simulation on transport barriers Projections of transport barrier physics to ITER For each topic there was an invited talk presenting an overview of the topic, based on contributions to the meeting and on recently published external results. The six invited talks were: A Leonard (GA, USA): Progress in characterization of the H-mode pedestal and L-H transition N Oyama (JAEA, Japan): Progress and issues in physics understanding of dynamics, mitigation and control of ELMs J Rice (MIT, USA): Spontaneous rotation and momentum transport in tokamak plasmas K Ida (NIFS, Japan): Transport barriers in non-axisymmetric magnetic fields F Jenko (IPP, Germany): Transport barriers: Recent progress in theory and simulation T Hoang (CEA, France): Internal transport barriers: Projection to ITER Every talk satisfied the objective of the meeting. A discussion period followed each invited talk in order to expand physics understandings, projection capabilities, and the direction of research around the topic. Short talks were presented by contributing speakers in addition to questions, answers, comments and discussion among the participants. For each topic there was an associated poster session for contributed papers, and lively discussion took place in front of every poster. Through the meeting six invited papers and 77 contributed papers were presented in total. The final session of the meeting was devoted to summaries; R Groebner, T S Hahm and K Ida of the IAC summarized the fruits of topics 1 and 2, 3 and 5, and 4 and 6, respectively. I would like to thank Dr A Malaquias, the IAEA Scientific Secretary, for his continuous support and useful suggestions on the arrangements of the meeting. I am very grateful to the IAC members for their cooperation in selecting topics and invited speakers, and for their important advices on the meeting strategy and proceedings publication. I also wish to express my gratitude to LOC colleagues for their hard work organizing the meeting. Young students of the University of Tsukuba helped us during the meeting. Financial and personel support from JAEA and the University of Tsukuba were essential. Finally I would like to acknowledge the participants of the meeting and the referees for the present proceedings. All of the above contributions contributed to the success of the meeting. Tomonori Takizuka Editor Group photograph International Advisory Committee T Takizuka (Japan Atomic Energy Agency, Japan: Chair) R J Groebner (General Atomics, USA) T S Hahm (Princeton Plasma Physics Laboratory, USA) A E Hubbard (MIT Plasma Science and Fusion Center, USA) K Ida (National Institute for Fusion Science, Japan) S V Lebedev (Ioffe Institute, Russia) G Saibene (EFDA CSU Garching, Germany) W Suttrop (Max-Plank-Institut für Plasmaphysik, Germany) Additional information about this meeting (H-mode-TM-11) is available in its homepage http://www-jt60.naka.jaea.go.jp/h-mode-tm-11/. List of Participants N Aiba (Japan Atomic Energy Agency, Japan) T Akiyama (National Institute for Fusion Science, Japan) N Asakura (Japan Atomic Energy Agency, Japan) L G Askinazi (Ioffe Institute, Russia) M N A Beurskens (EURATOM/UKAEA Fusion Association, UK) J D Callen (University of Wisconsin, USA) T Cho (University of Tsukuba, Japan) P C DeVries (EURATOM/UKAEA Fusion Association, UK) X T Ding (Southwestern Institute of Physics, China) E J Doyle (University of California, Los Angels, USA) A Fukuyama (Kyoto University, Japan) P Gohil (General Atomics, USA) R J Groebner (General Atomics, USA) T S Hahm (Princeton Plasma Physics Laboratory, USA) N Hayashi (Japan Atomic Energy Agency, Japan) Y Higashiyama (Nagoya University, Japan) Y Higashizono (University of Tsukuba, Japan) M Hirata (University of Tsukuba, Japan) G T Hoang (Association Euratom-CEA sur la Fusion Controle, France) G M D Hogeweij (FOM-Institute for Plasma Physics Rijnhuizen, The Netherlands) M Honda (Japan Atomic Energy Agency, Japan) L D Horton (Max-Plank-Institut für Plasmaphysik, Germany) W A Houlberg (ITER Organization) A E Hubbard (MIT Plasma Science and Fusion Center, USA) J W Hughes (MIT Plasma Science and Fusion Center, USA) M Ichimura (University of Tsukuba, Japan) K Ida (National Institute for Fusion Science, Japan) T Ido (National Institute for Fusion Science, Japan) T Imai (University of Tsukuba, Japan) F Imbeaux (Association Euratom-CEA sur la Fusion Controle, France) A Itakura (University of Tsukuba, Japan) K Itoh (National Institute for Fusion Science, Japan) S-I Itoh (Kyushu University, Japan) F Jenko (Max-Plank-Institut für Plasmaphysik, Germany) D Kalupin (Institut für Plasmaphysik, Forschungszentrum Jülich GmbH, Germany) Y Kamada (Japan Atomic Energy Agency, Japan) N Kasuya (National Institute for Fusion Science, Japan) I Katanuma (University of Tsukuba, Japan) M Kimura (Kyushu University, Japan) A Kirk (EURATOM/UKAEA Fusion Association, UK) S Kitajima (Tohoku University, Japan) S Kobayashi (Kyoto University, Japan) T Kobuchi (Tohoku University, Japan) J Kohagura (University of Tsukuba, Japan) P T Lang (Max-Plank-Institut für Plasmaphysik, Germany) S V Lebedev (Ioffe Institute, Russia) A W Leonard (General Atomics, USA) J Q Li (Kyoto University, Japan) A Malaquias (International Atomic Energy Agency) Y R Martin (Centre de Recherches en Physique des Plasmas, EPFL, Switzerland) C J McDevitt (University of California, San Diego, USA) D C McDonald (EURATOM/UKAEA Fusion Association, UK) H Meyer (EURATOM/UKAEA Fusion Association, UK) C A Michael (National Institute for Fusion Science, Japan) K Miki (Kyushu University, Japan) R Minami (University of Tsukuba, Japan) T Minami (National Institute for Fusion Science, Japan) Y Miyata (University of Tsukuba, Japan) N Miyato (Japan Atomic Energy Agency, Japan) Y Motegi (University of Tsukuba, Japan) V Mukhovatov (ITER Organization) S Murakami (Kyoto University, Japan) Y Nagashima (Kyushu University, Japan) Y Nakashima (University of Tsukuba, Japan) T Numakura (University of Tsukuba, Japan) S Ohshima (National Institute for Fusion Science, Japan) T Oishi (National Institute for Fusion Science, Japan) T Onjun (Sirindhorn International Institute of Technology, Thailand) T H Osborne (GENERAL Atomics, USA) N Oyama (Japan Atomic Energy Agency, Japan) T Ozeki (Japan Atomic Energy Agency, Japan) V Parail (EURATOM/UKAEA Fusion Association, UK) A Polevoi (ITER Organization, France) J E Rice (MIT Plasma Science and Fusion Center, USA) F Ryter (Max-Plank-Institut für Plasmaphysik, Germany) H Saimaru (University of Tsukuba, Japan) R Sakamoto (National Institute for Fusion Science, Japan) Y Sakamoto (Japan Atomic Energy Agency, Japan) M Sasaki (University of Tokyo, Japan) Y Shi (Institute of Plasma Physics, Chinese Academy of Science, China) A Shimizu (National Institute for Fusion Science, Japan) T Shimozuma (National Institute for Fusion Science, Japan) P B Snyder (General Atomics, USA) C Suzuki (National Institute for Fusion Science, Japan) H Takahashi (National Institute for Fusion Science, Japan) Y Takahashi (Nagoya University, Japan) Y Takeiri (National Institute for Fusion Science, Japan) H Takenaga (Japan Atomic Energy Agency, Japan) M Takeuchi (Nagoya University, Japan) T Takizuka (Japan Atomic Energy Agency, Japan) N Tamura (National Institute for Fusion Science, Japan) K Tanaka (National Institute for Fusion Science, Japan) S Tokuda (Japan Atomic Energy Agency, Japan) S Tokunaga (Kyushu University, Japan) G Turri (Centre de Recherches en Physique des Plasmas, EPFL, Switzerland) H Urano (Japan Atomic Energy Agency, Japan) H Utoh (Tohok University, Japan) K Uzawa (Kyoto University, Japan) M Valovic (EURATOM/UKAEA Fusion Association, UK) L Vermare (Max-Plank-Institut für Plasmaphysik, Germany) F Watanabe (Nagoya University, Japan) M Yagi (Kyushu University, Japan) Y Yamaguchi (University of Tsukuba, Japan) K Yamazaki (Nagoya University, Japan) M Yokoyama (National Institute for Fusion Science, Japan) M Yoshida (Japan Atomic Energy Agency, Japan) M Yoshinuma (National Institute for Fusion Science, Japan)

Spacelab

NASA Image and Video Library

1983-01-01

This photograph shows the Spacelab 1 module and pallet ready to be installed in the cargo bay of the Space Shuttle Orbiter Columbia at the Kennedy Space Center. The overall goal of the first Spacelab mission was to verify its Space performance through a variety of scientific experiments. The investigation selected for this mission tested the Spacelab hardware, flight and ground systems, and crew to demonstrate their capabilities for advanced research in space. However, Spacelab 1 was not merely a checkout flight or a trial run. Important research problems that required a laboratory in space were scheduled for the mission. Spacelab 1 was a multidisciplinary mission; that is, investigations were performed in several different fields of scientific research. These fields were Astronomy and Solar Physics, Space Plasma Physics, Atmospheric Physics and Earth Observations, Life Sciences, and Materials Science. Spacelab 1 was launched aboard the Space Shuttle Columbia (STS-9 mission) on November 28, 1983.

Validation metrics for turbulent plasma transport

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, C., E-mail: chholland@ucsd.edu

Developing accurate models of plasma dynamics is essential for confident predictive modeling of current and future fusion devices. In modern computer science and engineering, formal verification and validation processes are used to assess model accuracy and establish confidence in the predictive capabilities of a given model. This paper provides an overview of the key guiding principles and best practices for the development of validation metrics, illustrated using examples from investigations of turbulent transport in magnetically confined plasmas. Particular emphasis is given to the importance of uncertainty quantification and its inclusion within the metrics, and the need for utilizing synthetic diagnosticsmore » to enable quantitatively meaningful comparisons between simulation and experiment. As a starting point, the structure of commonly used global transport model metrics and their limitations is reviewed. An alternate approach is then presented, which focuses upon comparisons of predicted local fluxes, fluctuations, and equilibrium gradients against observation. The utility of metrics based upon these comparisons is demonstrated by applying them to gyrokinetic predictions of turbulent transport in a variety of discharges performed on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)], as part of a multi-year transport model validation activity.« less

Fully microscopic analysis of laser-driven finite plasmas using the example of clusters

NASA Astrophysics Data System (ADS)

Peltz, Christian; Varin, Charles; Brabec, Thomas; Fennel, Thomas

2012-06-01

We discuss a microscopic particle-in-cell (MicPIC) approach that allows bridging of the microscopic and macroscopic realms of laser-driven plasma physics. The simultaneous resolution of collisions and electromagnetic field propagation in MicPIC enables the investigation of processes that have been inaccessible to rigorous numerical scrutiny so far. This is illustrated by the two main findings of our analysis of pre-ionized, resonantly laser-driven clusters, which can be realized experimentally in pump-probe experiments. In the linear response regime, MicPIC data are used to extract the individual microscopic contributions to the dielectric cluster response function, such as surface and bulk collision frequencies. We demonstrate that the competition between surface collisions and radiation damping is responsible for the maximum in the size-dependent lifetime of the Mie surface plasmon. The capacity to determine the microscopic underpinning of optical material parameters opens new avenues for modeling nano-plasmonics and nano-photonics systems. In the non-perturbative regime, we analyze the formation and evolution of recollision-induced plasma waves in laser-driven clusters. The resulting dynamics of the electron density and local field hot spots opens a new research direction for the field of attosecond science.

A table top experiment to study plasma confined by a dipole magnet

NASA Astrophysics Data System (ADS)

Bhattacharjee, Sudeep; Baitha, Anuj Ram

2016-10-01

There has been a long quest to understand charged particle generation, confinement and underlying complex processes in a plasma confined by a dipole magnet. Our earth's magnetosphere is an example of such a naturally occurring system. A few laboratory experiments have been designed for such investigations, such as the Levitated Dipole Experiment (LDX) at MIT, the Terella experiment at Columbia university, and the Ring Trap-1 (RT-1) experiment at the University of Tokyo. However, these are large scale experiments, where the dipole magnetic field is created with superconducting coils, thereby, necessitating power supplies and stringent cryogenic requirements. We report a table top experiment to investigate important physical processes in a dipole plasma. A strong cylindrical permanent magnet, is employed to create the dipole field inside a vacuum chamber. The magnet is suspended and cooled by circulating chilled water. The plasma is heated by electromagnetic waves of 2.45 GHz and a second frequency in the range 6 - 11 GHz. Some of the initial results of measurements and numerical simulation of magnetic field, visual observations of the first plasma, and spatial measurements of plasma parameters will be presented.

Enabling Planetary Geodesy With the Deep Space Network

NASA Astrophysics Data System (ADS)

Park, R. S.; Asmar, S. W.; Armstrong, J. W.; Buccino, D.; Folkner, W. M.; Iess, L.; Konopliv, A. S.; Lazio, J.

2015-12-01

For five decades of planetary exploration, missions have carried out Radio Science experiments that led to numerous discoveries in planetary geodesy. The interior structures of many planets, large moons, asteroids and comet nuclei have been modeled based on their gravitational fields and dynamical parameters derived from precision Doppler and range measurements, often called radio metrics. Advanced instrumentation has resulted in the high level of data quality that enabled scientific breakthroughs. This instrumentation scheme, however, is distributed between elements on the spacecraft and others at the stations of the Deep Space Network (DSN), making the DSN a world-class science instrument. The design and performance of the DSN stations directly determines the quality of the science observables and radio link-based planetary geodesy observations are established by methodologies and capabilities of the DSN. In this paper, we summarize major recent discoveries in planetary geodesy at the rocky planets and the Moon, Saturnian and Jovian satellites, Phobos, and Vesta; experiments and analysis in progress at Ceres and Pluto; upcoming experiments at Jupiter, Saturn and Mars (InSight), and the long-term outlook for approved future missions with geodesy objectives. The DSN's role will be described along the technical advancements in DSN transmitters, receivers, atomic clocks, and other specialized instrumentation, such as the Advanced Water Vapor Radiometer, Advanced Ranging Instrument, as well as relevant mechanical and electrical components. Advanced techniques for calibrations of known noise sources and Earth's troposphere, ionosphere, and interplanetary plasma are also presented. A typical error budget will be presented to aid future investigations in carrying out trade-off studies in the end-to-end system performance.

Atmospheric and Space Sciences: Ionospheres and Plasma Environments

NASA Astrophysics Data System (ADS)

Yiǧit, Erdal

2018-01-01

The SpringerBriefs on Atmospheric and Space Sciences in two volumes presents a concise and interdisciplinary introduction to the basic theory, observation & modeling of atmospheric and ionospheric coupling processes on Earth. The goal is to contribute toward bridging the gap between meteorology, aeronomy, and planetary science. In addition recent progress in several related research topics, such atmospheric wave coupling and variability, is discussed. Volume 1 will focus on the atmosphere, while Volume 2 will present the ionospheres and the plasma environments. Volume 2 is aimed primarily at (research) students and young researchers that would like to gain quick insight into the basics of space sciences and current research. In combination with the first volume, it also is a useful tool for professors who would like to develop a course in atmospheric and space physics.

Magnetothermodynamics: measurements of the thermodynamic properties in a relaxed magnetohydrodynamic plasma

NASA Astrophysics Data System (ADS)

Kaur, M.; Barbano, L. J.; Suen-Lewis, E. M.; Shrock, J. E.; Light, A. D.; Schaffner, D. A.; Brown, M. B.; Woodruff, S.; Meyer, T.

2018-02-01

We have explored the thermodynamics of compressed magnetized plasmas in laboratory experiments and we call these studies `magnetothermodynamics'. The experiments are carried out in the Swarthmore Spheromak eXperiment device. In this device, a magnetized plasma source is located at one end and at the other end, a closed conducting can is installed. We generate parcels of magnetized plasma and observe their compression against the end wall of the conducting cylinder. The plasma parameters such as plasma density, temperature and magnetic field are measured during compression using HeNe laser interferometry, ion Doppler spectroscopy and a linear probe array, respectively. To identify the instances of ion heating during compression, a PV diagram is constructed using measured density, temperature and a proxy for the volume of the magnetized plasma. Different equations of state are analysed to evaluate the adiabatic nature of the compressed plasma. A three-dimensional resistive magnetohydrodynamic code (NIMROD) is employed to simulate the twisted Taylor states and shows stagnation against the end wall of the closed conducting can. The simulation results are consistent to what we observe in our experiments.

LAPTAG: Los Angeles Physics Teachers Alliance Group and the UCLA Basic Plasma User Facility.

NASA Astrophysics Data System (ADS)

Gekelman, Walter

2001-10-01

LAPTAG was founded in 1993 during a meeting sponsored by the APS, which encouraged high schools and Universities to form alliances. There are currently about twenty high schools, several community colleges and two Universities (UCLA and USC) involved. At first LAPTAG organized tours of laboratories at UCLA, USC, JPL, General Atomics and the Mt. Wilson Observatory and had meetings in which issues on curricula were discussed. It became obvious after awhile that in order for the group to last that projects were necessary. An early project involved having the high school faculty and students create Websites for most of the schools. This was before most the schools could afford Internet connections and Web authoring tools did not exist. Then with funding from the UC Office of the President, a seismology project was initiated and ten schools received seismometers. There were lectures by geologists and staff members of the Southern California Earthquake center; results were reported on the Web. In the spring of 1999 LAPTAG gave seven posters at the Condensed Matter APS meeting in Los Angeles. A web based astronomy course was created and high school students controlled the Mount Wilson telescope remotely and studied a variable star. Our latest project, funded by the Department of Energy resulted in the construction of a plasma lab dedicated to LAPTAG. The lab has equipment that is used by practicing plasma physicists (tone-burst generators, digital scopes, digital data acquisition and computerized probe drives) as well as software (LabView, PVwave). The high school students and teachers built the machine and all the associated diagnostics. Examples of the experiments will be given, however it is not a cookbook lab. As new experiments are introduced the same difficulties we all face must be overcome; the students take part in this. The LAPD laboratory is now a National User Facility and LAPTAG is a key component of its outreach program. We have met with the director of science for the Los Angeles Unified School district, and others, to muster resources to allow many more schools to participate. This and plans for other programs such as the Integration of Art and Science, will be presented.

EXPERIMENTS WITH PLASMA RINGS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alfven, H.; Lindberg, L.; Mitlid, P.

1960-03-01

The construction of a coaxial plasma gun is described. At its output end the gun is provided with a radial magnetic field, which is trapped by the plasma. The plasma from the gun is studied by photographic and magnetic methods. It is demonstrated that the gun produces magnetized plasma rings with the same basic structure as the rings obtained in toroidal pinch experiments. When the plasma rings are formed, the magnetic field lines from the gun break, a result which is of interest from a theoretical point of view. (auth)

Cortisol in saliva and plasma of cattle after ACTH administration and milking.

PubMed

Negrão, J A; Porcionato, M A; de Passillé, A M; Rushen, J

2004-06-01

Interest in the measurement of salivary cortisol has increased recently because saliva can be easily collected before and after an imposed stress. This study evaluated the relationship between plasma and salivary concentrations of cortisol following ACTH administration in calves (experiment 1) and machine milking of adult cows (experiment 2). A catheter was inserted into the jugular vein of all animals 72 h before the beginning of experiments. Blood and saliva samples were collected before and after ACTH administration (0.6 IU/kg BW) in calves or before and after machine milking of cows. Using a cotton swab, each saliva sample was taken immediately following the blood sample. In general, cortisol profiles were similar in plasma and saliva and correlated in both experiments; however, plasma concentrations were significantly higher than salivary concentrations. In addition, the differences between cortisol concentrations measured in saliva and plasma within each experiment varied substantially between animals and samples. Furthermore, in experiment 2, nearly 10% of salivary samples were below limits of detection. The sharp peaks in cortisol after ACTH administration in both the plasma and saliva were reflected adrenal stimulation. In addition, increases in cortisol in response to milking in both the plasma and saliva suggest that salivary sampling is a reliable option when studying cortisol responses to normal physiological events.

Plasma wave observations during ion gun experiments

NASA Astrophysics Data System (ADS)

Olsen, R. C.; Weddle, L. E.; Roeder, J. L.

1990-06-01

Experiments in charge control on the AF/NASA P78-2 (SCATHA) satellite were conducted with a plasma/ion source in the inner magnetosphere. These experiments were monitored with plasma wave instruments capable of high temporal and frequency resolution in the 0-6 kHz frequency range. Ion gun experiments revealed two distinct classes of behavior. Nonneutralized ion beam operation at 1 mA, 1kV resulted in arcing signatures (spiky in time, broad frequency range), coincident with induced satellite potentials of -600 to -900 V. This signature disappeared when the accelerating voltage was switched off or the beam was neutralized. The signal is attributed to arcing between differentially charged surfaces. An additional feature was noted in the 100-kHz channel of the wave receiver. During emission of dense, low-energy plasma, a signal is generated which may be at the upper hybrid, or plasma frequency for the local plasma.

Measurements of the canonical helicity evolution of a gyrating kinked plasma column

NASA Astrophysics Data System (ADS)

von der Linden, Jens; Sears, Jason; Intrator, Thomas; You, Setthivoine

2017-10-01

Conversions between kinetic and magnetic energy occur over a wide range of plasma scales as exhibited in astrophysical and solar dynamos, and reconnection in the solar corona and laboratory experiments. Canonical flux tubes present the distinct advantage of reconciling all plasma regimes - e.g. kinetic, two-fluid, and MHD - with the topological concept of helicity: twists, writhes, and linkages. This poster presents the first visualization and analysis of the 3D dynamics of canonical flux tubes and their relative helicity evolution from experimental measurements. Ion and electron canonical flux tubes are visualized from Mach, triple, and Ḃ probe measurements at over 10,000 spatial locations of a gyrating kinked plasma column. The flux tubes co-gyrate with the peak density and electron temperature in and out of a measurement volume. The electron and ion canonical flux tubes twist with opposite handedness and the ion flux tube writhes around the electron flux tube. The relative cross helicity between the magnetic and ion flow vorticity flux tubes dominates the relative ion canonical helicity and is anticorrelated with the relative magnetic helicity. The 3D nature of the kink and a reverse eddy current affect the helicity evolution. This work is supported by DOE Grant DE-SC0010340 and the DOE Office of Science Graduate Student Research Program and prepared in part by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-734669.

A Theory for Rapid Charging Events on the International Space Station

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.; Craven, Paul D.; Minow, Joseph I.; Wright, Kenneth H., Jr.

2009-01-01

The Floating Potential Measurement Unit (FPMU) has detected high negative amplitude rapid charging events (RCEs) on the International Space Station (ISS) at the morning terminator. These events are larger and more rapid than the ISS morning charging events first seen by the Floating Potential Probe (FPP) on ISS in 2001. In this paper, we describe a theory for the RCEs that further elucidates the nature of spacecraft charging in low Earth orbit (LEO) in a non-equilibrium situation. The model accounts for all essential aspects of the newly discovered phenomenon, and is amenable to testing on-orbit. Predictions of the model for the amplitude of the ISS RCEs for the full set of ISS solar arrays and for the coming solar cycle are given, and the results of modeling by the Environments WorkBench (EWB) are compared to the observed events to show that the phenomenon can be explained by solar array driven charging. The situation is unique because the coverglasses have not yet reached equilibrium with the surrounding plasma during the RCEs. Finally, a prescription for further use of the ISS for investigating fundamental plasma physics in LEO is given. Already, plasma and charging monitoring instruments on ISS have taught us much about spacecraft interactions with the dense LEO plasma, and we expect they will continue to yield more valuable science when the Japanese Experiment Module (JEM) is in place.

Experimental Validation of a Branched Solution Model for Magnetosonic Ionization Waves in Plasma Accelerators

NASA Astrophysics Data System (ADS)

Underwood, Thomas; Loebner, Keith; Cappelli, Mark

2015-11-01

Detailed measurements of the thermodynamic and electrodynamic plasma state variables within the plume of a pulsed plasma accelerator are presented. A quadruple Langmuir probe operating in current-saturation mode is used to obtain time resolved measurements of the plasma density, temperature, potential, and velocity along the central axis of the accelerator. This data is used in conjunction with a fast-framing, intensified CCD camera to develop and validate a model predicting the existence of two distinct types of ionization waves corresponding to the upper and lower solution branches of the Hugoniot curve. A deviation of less than 8% is observed between the quasi-steady, one-dimensional theoretical model and the experimentally measured plume velocity. This work is supported by the U.S. Department of Energy Stewardship Science Academic Program in addition to the National Defense Science Engineering Graduate Fellowship.

MHD Simulation of Magnetic Nozzle Plasma with the NIMROD Code: Applications to the VASIMR Advanced Space Propulsion Concept

NASA Astrophysics Data System (ADS)

Tarditi, Alfonso G.; Shebalin, John V.

2002-11-01

A simulation study with the NIMROD code [1] is being carried on to investigate the efficiency of the thrust generation process and the properties of the plasma detachment in a magnetic nozzle. In the simulation, hot plasma is injected in the magnetic nozzle, modeled as a 2D, axi-symmetric domain. NIMROD has two-fluid, 3D capabilities but the present runs are being conducted within the MHD, 2D approximation. As the plasma travels through the magnetic field, part of its thermal energy is converted into longitudinal kinetic energy, along the axis of the nozzle. The plasma eventually detaches from the magnetic field at a certain distance from the nozzle throat where the kinetic energy becomes larger than the magnetic energy. Preliminary NIMROD 2D runs have been benchmarked with a particle trajectory code showing satisfactory results [2]. Further testing is here reported with the emphasis on the analysis of the diffusion rate across the field lines and of the overall nozzle efficiency. These simulation runs are specifically designed for obtaining comparisons with laboratory measurements of the VASIMR experiment, by looking at the evolution of the radial plasma density and temperature profiles in the nozzle. VASIMR (Variable Specific Impulse Magnetoplasma Rocket, [3]) is an advanced space propulsion concept currently under experimental development at the Advanced Space Propulsion Laboratory, NASA Johnson Space Center. A plasma (typically ionized Hydrogen or Helium) is generated by a RF (Helicon) discharge and heated by an Ion Cyclotron Resonance Heating antenna. The heated plasma is then guided into a magnetic nozzle to convert the thermal plasma energy into effective thrust. The VASIMR system has no electrodes and a solenoidal magnetic field produced by an asymmetric mirror configuration ensures magnetic insulation of the plasma from the material surfaces. By powering the plasma source and the heating antenna at different levels it is possible to vary smoothly of the thrust-to-specific impulse ratio while maintaining maximum power utilization. [1] http://www.nimrodteam.org [2] A. V. Ilin et al., Proc. 40th AIAA Aerospace Sciences Meeting, Reno, NV, Jan. 2002 [3] F. R. Chang-Diaz, Scientific American, p. 90, Nov. 2000

Dynamics of Plasma Jets and Bubbles Launched into a Transverse Background Magnetic Field

NASA Astrophysics Data System (ADS)

Zhang, Yue

2017-10-01

A coaxial magnetized plasma gun has been utilized to launch both plasma jets (open B-field) and plasma bubbles (closed B-field) into a transverse background magnetic field in the HelCat (Helicon-Cathode) linear device at the University of New Mexico. These situations may have bearing on fusion plasmas (e.g. plasma injection for tokamak fueling, ELM pacing, or disruption mitigation) and astrophysical settings (e.g. astrophysical jet stability, coronal mass ejections, etc.). The magnetic Reynolds number of the gun plasma is 100 , so that magnetic advection dominates over magnetic diffusion. The gun plasma ram pressure, ρjetVjet2 >B02 / 2μ0 , the background magnetic pressure, so that the jet or bubble can easily penetrate the background B-field, B0. When the gun axial B-field is weak compared to the gun azimuthal field, a current-driven jet is formed with a global helical magnetic configuration. Applying the transverse background magnetic field, it is observed that the n = 1 kink mode is stabilized, while magnetic probe measurements show contrarily that the safety factor q(a) drops below unity. At the same time, a sheared axial jet velocity is measured. We conclude that the tension force arising from increasing curvature of the background magnetic field induces the measured sheared flow gradient above the theoretical kink-stabilization threshold, resulting in the emergent kink stabilization of the injected plasma jet. In the case of injected bubbles, spheromak-like plasma formation is verified. However, when the spheromak plasma propagates into the transverse background magnetic field, the typical self-closed global symmetry magnetic configuration does not hold any more. In the region where the bubble toroidal field opposed the background B-field, the magneto-Rayleigh-Taylor (MRT) instability has been observed. Details of the experiment setup, diagnostics, experimental results and theoretical analysis will be presented. Supported by the National Science Foundation under Grant No. AST-0613577 and the Army Research Office under Award No. W911NF1510480. This work performed in collaboration with D. Fisher, A. G. Lynn, M Gilmore, and S. C. Hsu.

Studies on Charge Variation and Waves in Dusty Plasmas

NASA Astrophysics Data System (ADS)

Kausik, Siddhartha Sankar

Plasma and dust grains are both ubiquitous ingredients of the universe. The interplay between them has opened up a new and fascinating research domain, that of dusty plasmas, which contain macroscopic particles of solid matter besides the usual plasma constituents. The research in dusty plasmas received a major boost in the early eighties with Voyager spacecraft observation on the formation of Saturn rings. Dusty plasmas are defined as partially or fully-ionized gases that contain micron-sized particles of electrically charged solid material, either dielectric or conducting. The physics of dusty plasmas has recently been studied intensively because of its importance for a number of applications in space and laboratory plasmas. This thesis presents the experimental studies on charge variation and waves in dusty plasmas. The experimental observations are carried out in two different experimental devices. Three different sets of experiments are carried out in two different experimental devices. Three different sets of experiments are carried out to study the dust charge variation in a filament discharge argon plasma. The dust grains used in these experiments are grains of silver. In another get of experiment, dust acoustic waves are studied in a de glow discharge argon plasma. Alumina dust grains are sprinkled in this experiment. The diagnostic tools used in these experiments are Langmuir probe and Faraday cup. The instruments used in these experiments are electrometer, He-Ne laser and charge coupled device (CCD) camera. Langmuir probe is used to measure plasma parameters, while Faraday cup and electrometer are used to measure very low current (~pA) carried by a collimated dust beam. He-Ne laser illuminates the dust grains and CCD camera is used to capture the images of dust acoustic waves. Silver dust grains are produced in the dust chamber by gas-evaporation technique. Due to differential pressure maintained between the dust and plasma chambers, the dust grains move upward in the form of a collimated beam. Argon plasma is produced in an experimental setup consisting of a dust chamber, a plasma chamber and a diagnostic chamber (also called deflection chamber) by striking a discharge between incandescent tungsten filaments and the magnetic cage, which is grounded. Plasma thus produced is confined by a full line cusped magnetic field confinement system consisting of a cylindrically shaped cage made up of stainless steel channels filled up with cube shaped having 1.2 kG field strength at its surface.

Educational Outreach at CASPER

NASA Astrophysics Data System (ADS)

Hyde, Truell; Smith, Bernard; Carmona-Reyes, Jorge

2007-11-01

The CASPER Educational Outreach program with support from the Department of Education, the Department of Labor and the National Science Foundation advances physics education through a variety of avenues including CASPER's REU / RET program, High School Scholars Program, spiral curriculum development program and the CASPER Physics Circus. These programs impact K-12 teachers and students providing teachers with curriculum, supporting hands-on material and support for introducing plasma and basic physical science into the classroom. The most visible of the CASPER outreach programs is the Physics Circus, created during the 1999-2000 school year and funded since that time through two large grants from the Department of Education. The Physics Circus is part of GEAR UP Waco (Gaining Early Awareness and Readiness for Undergraduate Programs) and was originally one of 185 grants awarded nationwide by the U. S. Department of Education in 1999 to help 200,000 disadvantaged children prepare for and gain a pathway to undergraduate programs. The CASPER Physics Circus is composed of intense science explorations, physics demonstrations, hands-on interactive displays, theatrical performances, and excellent teaching experiences. Examples and efficacy data from the above will be discussed.

Intense fusion neutron sources

NASA Astrophysics Data System (ADS)

Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

2010-04-01

The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

First experiments probing the collision of parallel magnetic fields using laser-produced plasmas

DOE PAGES

Rosenberg, M. J.; Li, C. K.; Fox, W.; ...

2015-04-08

Novel experiments to study the strongly-driven collision of parallel magnetic fields in β~10, laser-produced plasmas have been conducted using monoenergetic proton radiography. These experiments were designed to probe the process of magnetic flux pileup, which has been identified in prior laser-plasma experiments as a key physical mechanism in the reconnection of anti-parallel magnetic fields when the reconnection inflow is dominated by strong plasma flows. In the present experiments using colliding plasmas carrying parallel magnetic fields, the magnetic flux is found to be conserved and slightly compressed in the collision region. Two-dimensional (2D) particle-in-cell (PIC) simulations predict a stronger flux compressionmore » and amplification of the magnetic field strength, and this discrepancy is attributed to the three-dimensional (3D) collision geometry. Future experiments may drive a stronger collision and further explore flux pileup in the context of the strongly-driven interaction of magnetic fields.« less