Download or read book Calculation of the Fast Ion Source Distribution from Neutral Beam Injection Into a Tokamak Plasma written by Daniel J. Beckett and published by . This book was released on 1976 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Techniques for Calculating Heat and Particle Source Rates Due to Neutral beam Injection in Axisymmetric Tokamaks written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A set of numerical techniques are described for calculating heat and particle source rates due to neutral beam injection in axisymmetric tokamaks. While these techniques consume a substantial amount of computer time, they take into account a number of significant, and normally neglected, effects. Examples of these effects are reionization of escaping charge exchanged beam particles, finite fast ion orbit excursions, beam deposition through collisions of beam neutrals with circulating beam ions, and the transport of thermal neutrals in the plasma due to charge changing collisions with beam ions.

Download or read book Fusion Energy Update written by and published by . This book was released on 1982-04 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Prompt Fast Ion Losses from Neutral Beam Injection in the DIII D Tokamak written by Derek Aiden Sutherland and published by . This book was released on 2012 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of the prompt losses of injected neutral beam born fast ions was conducted on the DIII-D tokamak at General Atomics using scintillator based fast ion loss detectors (FILD) and a reverse orbit calculation code. Prompt losses, also called first orbit losses, result from injected neutrals that are ionized on orbits that terminate to the outer wall before making a complete neoclassical, poloidal revolution. A strike map code has been developed which generates meshes that overlay optical fast ion signals from the FILD scintillator, providing a measurement of the pitch angles and gyroradii of incident fast ions. The pitch angles and gyroradii of incident ions are inputs to a reverse orbit calculation code used to calculate the trajectories of the incident ions in reverse time back to their birth at the intersection of the reverse orbit and an overlaid neutral beam injection footprint. The megahertz (MHz) sampling frequency of the FILD scintillator, along with finer time resolution neutral beam signals, enabled a comparison of the measured time delay between the onset of the neutral beam injection and the measured FILD loss signals with the calculated transit time based on the path length of the simulated reverse orbit. Consistency between the experimentally measured transit times and the simulation orbit times was observed. This result indicates the generated strike maps which provide a measurement of incident ions' gyroradii and pitch angles are accurate. This study supplements current studies seeking to improve the understanding of fast ion transport due to magnetohydrodynamic (MHD) activity, such as reverse shear Alfven eigenmodes (RSAEs) and toroidal Alfven eigenmodes (TAEs), which will be of great importance for predominately self-heated reactor scenarios.

Download or read book Heating in Toroidal Plasmas written by T. Consoli and published by Elsevier. This book was released on 2016-06-03 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heating in Toroidal Plasmas, Volume 1 documents the proceedings of the symposium held at the Centre d'Etudes Nucléaires, Grenoble, France, on July 3-7, 1978. This volume compiles 52 articles that are thematically grouped in this publication. The first two sets of papers focus on the general theory and topics on neutral beam injection. The subsequent group of papers studies heating at ion cyclotron- and lower frequencies. A bulk of papers compiled in this volume examines lower hybrid resonance heating. The remaining set of papers is devoted to electron cyclotron heating. This volume will be invaluable to physics students and others interested in studying plasma, specifically the method of heating in toroidal plasmas.

Download or read book Neutral Beam Injection Into a Tokamak I Fast Ion Spatial Distribution for Tangential Injection written by and published by . This book was released on 1973 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reviews of Plasma Physics written by M. Leontovich and published by Springer. This book was released on 1987-05-01 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1977 with total page 900 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1994-11 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration. Technical Information Center and published by . This book was released on 1977 with total page 1066 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energetic Ion Distribution Resulting from Neutral Beam Injection in Tokamaks written by John D. Gaffey and published by . This book was released on 1976 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Documentation of Plasma Physics Pt 1 Experimental Plasma Physics and Theoretical Plasma Physics written by and published by . This book was released on 1981 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Fusion written by and published by . This book was released on 2006-12 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Velocity space Resolved Fast ion Measurements in the DIII D Tokamak written by Christopher Michael Muscatello and published by . This book was released on 2012 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superthermal ions in tokamak plasmas play a critical role in heating and current drive, and their confinement within the core of the plasma is crucial for obtaining ignition and sustaining burn in future reactors. At the DIII-D tokamak, a suite of fast-ion measurements is available to diagnose various properties of the superthermal population. This thesis work involves a contribution to DIII-D's fast-ion diagnostic collection: the 2nd generation fast-ion deuterium alpha (2G FIDA) detector. FIDA works on the principle of measuring the light that is emitted from neutralized fast ions that undergo charge exchange events with injected neutral atoms. 2G FIDA complements the other FIDA installations on DIII-D with its unique velocity-space sampling volume. Output from a synthetic diagnostic code (FIDAsim) that predicts FIDA emission levels is compared with measurements from 2G FIDA. We find that, while the predicted and measured shapes of the FIDA spectra agree well, the absolute magnitude of the spectral amplitudes are inconsistent. Results from various FIDAsim trials are presented adjusting several parameters, and it is hypothesized that mischaracterization of the diagnostic neutral beams is a major source of error. Instabilities in tokamaks can cause fast-ion transport. The sawtooth instability is particularly important because the crash phase has been observed to cause reductions up to 50% in the central fast-ion density. Passing ions of all energies are redistributed, but only low energy trapped ions suffer redistribution. The observations are consistent with transport by flux-attachment. Comparisons with theory suggest that the intensity of sawtooth-induced transport depends on the magnitude of toroidal drift. Instabilities characterized by toroidal and poloidal mode numbers and real frequency can coherently interact with energetic particles through mode-particle resonances. During a sawtooth crash, even fast ions whose energies are above the threshold for flux-attachment can experience transport if their orbits satisfy the bounce-precessional resonance condition. On DIII-D, a spatially localized population of beam ions accelerated above the injection energy by ion-cyclotron radio frequency (ICRF) heating is diminished at a sawtooth crash. Furthermore, fast-ion losses concurrent with sawtooth crashes are observed. Calculations show that mode-particle resonances could be responsible. Transport of energetic particles by resonant interactions pertains to many types of instabilities; other examples besides sawteeth will also be presented. Analysis shows that large amplitude modes cause significant resonant transport of fast particles. Even small amplitude modes can resonantly drive transport if multiple harmonics exist.

Download or read book Measurement and Simulation of Deuterium Balmer alpha Emission from First orbit Fast Ions and the Application to Neutral Density and General Fast ion Loss Detection in the DIII D Tokamak written by Nathan Glynn Bolte and published by . This book was released on 2015 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectra of the Balmer-alpha radiation of first-orbit fast ions after charge exchange with edge neutrals have been measured in the DIII-D tokamak. Several collimated optics systems view the edge region--while avoiding any active beams--and carry light to a spectrometer tuned to the region of the 656.1 nm deuterium-alpha line. Viewing geometry and the high energy of the lost ions produce Doppler shifts, which effectively separate the fast-ion contributions from the bright, cold edge light. Modulation of the fast-ion source allows for time-evolving background subtraction. A model has been developed for the spectra of these first-orbit fast ions. The passive fast-ion D-alpha simulation (P-FIDAsim) is a forward model consisting of an experimentally- validated beam model, an ion orbit-following code, a collisional-radiative model, and a synthetic spectrometer. Eighty-six experimental spectra were obtained using 6 different neutral beam fast-ion sources and 13 different viewing chords. Parameters such as plasma current, toroidal field, electron density, plasma cross-sectional shape, and number of x-points were varied. Uncalibrated experimental spectra have an overall Spearman rank correlation coefficient with the shape of simulated spectra of 0.58 with subsets of cases rising to a correlation of 0.80. A single set of calibrated spectra (shot 152817) was measured and is used to estimate the neutral density throughout the cross-section of the tokamak. This is done by inverting the simulated spectra in order to nd the best neutral density (in a least squares sense) required to best match the experimental spectra. The resulting 2D neutral density shows the expected increase toward each x-point. The average neutral density is found to be 3.3 x 105 cm ̄3 at the magnetic axis, 2.3 x 108 cm ̄3 in the core, 8.1 x 109 cm ̄3 at the plasma boundary, and 1.1 x 1011 cm ̄3 near the wall. A technique is developed which--after using first-orbit light to calibrate the system--can quantify losses from a wider variety of mechanisms. Fast-ion losses resulting from sawtooth crashes (shot 149941) is estimated to eject 1.2% of the fast-ion inventory, in good agreement with a 1.7% loss estimate made by the TRANSP code.