![Observation of Thomson Scattering from Ion Thermal Fluctuations in a Tokamak Plasma with a 385[mu]m Laser PDF](https://books.google.com/books/content/images/frontcover/AFcvHQAACAAJ?fife=w150-h200)
Author: Paul P. WoskovPublisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
Observation of Thomson Scattering from Ion Thermal Fluctuations in a Tokamak Plasma with a 385[mu]m Laser
![Observation of Thomson Scattering from Ion Thermal Fluctuations in a Tokamak Plasma with a 385[mu]m Laser PDF](https://books.google.com/books/content/images/frontcover/AFcvHQAACAAJ?fife=w80-h100)
Author: Paul P. WoskovIon Temperature Measurements of a Tokamak Plasma by Collective Thomson Scattering of D2O Laser Radiation
Author: Roland Behn (Physiker, Deutschland)Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
The Observation of Enhanced Thomson Scattering in Submicron-laser Plasmas
Author: Steven Howard BathaFluctuations in a Tokamak Plasma
Author: R. L. KubenaPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 228
Book Description
An experimental investigation of low frequency floating potential fluctuations (f d"200 kHz) in a research tokamak plasma using two spatially separated electrostatic probes has been performed. The spectra, correlation length, and the phase velocity of the fluctuations in both the radial and azimuthal direction have been determined. The propagation velocity in the toroidal direction was also measured and was found to be in the direction of electron current flow. The waves traveled azimuthally in the ion diamagnetic drift direction, even after the usual E x B rotation was taken into account. The electron density fluctuations associated with these oscillations were large, [delta]n/n [approximately] 0.35 - 0.50. The spectra were found to have regularly spaced peaks which seemed to be related to specific azimuthal modes (m =1,2,3, ..., etc.) A parametric study was made to determine what effect plasma parameters had on these peaks. During periods of high electron density in the first 2 msec of the plasma lifetime, strong sawtooth type oscillations were observed. These oscillations typically had frequencies of approximately 10 kHz and were also present when large amounts of neutral gas were added during the discharge by a process called "gas puffing." The results are compared with experimental observations made on other plasma devices with electric and magnetic probes and with microwave and CO2 laser scattering techniques. (The scattering measurements are complimentary to the probe measurements since, in the former case, the wavelength is fixed by the scattering angle, but the oscillations could not be spatially localized.) The oscillations in the Caltech torus were probably related to a drift-tearing type instability which is thought to play a major role in the anomalous particle and energy flux observed in tokamaks. Comparisons are made between current theory and the experimental results. However, the theory for the observed oscillations is still in a rudimentary stage of development, and it is hoped that the present investigation will stimulate future analytical work.
Theory of Thomson Scattering from a Weakly Ionized Plasma
Author: Richard G. SeasholtzPublisher:
ISBN:
Category : Plasma (Ionized gases)
Languages : en
Pages : 60
Book Description
Theory of Tokamak Plasmas
Author: R.B. WhitePublisher: North Holland
ISBN:
Category : Science
Languages : en
Pages : 388
Book Description
This is a graduate textbook on tokamak physics, designed to provide a basic introduction to plasma equilibrium, particle orbits, transport, and those ideal and resistive magnetohydrodynamic instabilities which dominate the behavior of a tokamak discharge, and to develop the mathematical methods necessary for their theoretical analysis.
High Power Gyrotron and Far Infrared Laser Collective Thomson Scattering Diagnostics in Burning Tokamak Plasmas
Author: David Yoon Hee RheeThomson Scattering from RF-excited Tokamak Plasmas
Author: Alan Stephen FisherThomson Scattering from Inertial Confinement Fusion Targets
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We have applied ultraviolet Thomson scattering to accurately measure the electron and ion temperature in high-density gas-filled hohlraums at the Nova laser facility. The implementation of a short-wavelength probe laser that operates at 263 nm (4[omega]) has allowed us for the first time to investigate scalings to high gas fill densities and to characterize the hohlraum conditions of the low-Z gas plasma. as well as of the high-Z wall plasma. These measurements have provided us with a unique data set that we use to make critical comparisons with radiation-hydrodynamic modeling using the code LASNEX. This code is presently being applied to design fusion targets for the National Ignition Facility. The Thomson scattering experiments show the existence of electron temperature gradients in the gas plasma that are well modeled when including a self-consistent calculation of magnetic fields. The fields are of relatively small strength not affecting the Thomson scattering spectra directly but limiting the electron thermal transport in the gas resulting into temperature gradients consistent with the experimental observations. In addition, the ion temperature data show that the stagnation time of the gas plasma on the hohlraum axis, which is driven by the radial inward flowing plasma, is sensitive to the gas fill density and is well described by the calculations.
Author: