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Low-noise collection system for the Thomson scattering diagnostic apparatus on ORMAK

Description: An automnted data collection system as designed and built for the ORMAK Thomson scattering apparatus is described. The system uses both gated photomultipliers and gated integrators; advantages of this approach are discussed. Four electron-temperature and electron-density measurements can be made during each plasma discharge, with measurements spaced as closely as 1 ms apart. Data are automatically digitized and stored in a computer for processing and display. (auth)
Date: January 1, 1973
Creator: Dyer, G.R. & Murakami, M.
Partner: UNT Libraries Government Documents Department

2XIIB computer data acquisition system

Description: All major plasma diagnostic measurements from the 2XIIB experiment are recorded, digitized, and stored by the computer data acquisition system. The raw data is then examined, correlated, reduced, and useful portions are quickly retrieved which direct the future conduct of the plasma experiment. This is done in real time and on line while the data is current. The immediate availability of this pertinent data has accelerated the rate at which the 2XII personnel have been able to gain knowledge in the study of plasma containment and fusion interaction. The up time of the experiment is being used much more effectively than ever before. This paper describes the hardware configuration of our data system in relation to various plasma parameters measured, the advantages of powerful software routines to reduce and correlate the data, the present plans for expansion of the system, and the problems we have had to overcome in certain areas to meet our original goals. (auth)
Date: November 18, 1975
Creator: Tyler, G.C.
Partner: UNT Libraries Government Documents Department

State-selective charge transfer cross sections for light ion impact of atomic hydrogen

Description: This article compares results of approaches applicable in a lower impact energy regime by benchmarking them using key experimental data in order to make knowledge of these cross sections available across the range parameters needed by fusion plasma diagnostics.
Date: January 15, 2015
Creator: Schultz, David R.; Stancil, P.C. & Havener, C.C.
Partner: UNT College of Arts and Sciences

Core Poloidal Rotation and Internal Trnasport Barrier Formation in TFTR

Description: Impurity poloidal rotation velocities have been measured in the core of TFTR plasmas using a new spectroscopic diagnostic. Two types of transitions to enhanced confinement in reversed shear plasmas are examined. A bifurcation in carbon poloidal rotation is observed to occur before the transition to enhanced confinement for one of these types, while other measured plasmas parameters remain constant. A narrow radial region with reversed poloidal rotation and rotational shear is established 60-100 ms before the transition, and is associated with a large negative radial electric field.
Date: January 1, 1998
Creator: Synakowski, E.J.; Levinton, F.M.; Zarnstorff, M.C.; Bell, R.E.; Batha, S.H. & al, et
Partner: UNT Libraries Government Documents Department

The TFTR E Parallel B Spectrometer for Mass and Energy Resolved Multi-Ion Charge Exchange Diagnostics

Description: The Charge Exchange Neutral Analyzer diagnostic for the Tokamak Fusion Test Reactor was designed to measure the energy distributions of both the thermal ions and the supra thermal populations arising from neutral-beam injection and ion cyclotron radio-frequency heating. These measurements yield the plasma ion temperature, as well as several other plasma parameters necessary to provide an understanding of the plasma condition and the performance of the auxiliary heating methods. For this application, a novel charge-exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory. The design and performance of this spectrometer is described in detail, including the effects of exposure of the microchannel plate detector to magnetic fields, neutrons, and tritium.
Date: January 1, 1998
Creator: Roquemore, A.L. & Medley, S.S.
Partner: UNT Libraries Government Documents Department

Ten-picosecond streak camera for the laser fusion program at LLL

Description: From electro-optical systems design conference; New York, New York. USA (18 Sep 1973). The development and operation of 10-picosecond streak cameras in the LLL laser fusion program are described. In addition, modifications to two TRW Model 1-D high-speed streak cameras are discussed. The compact cameras are completely self-contained, weigh about 27 kg, and occupy about 1/6 m/sup 2/ of bench space. Power consumption is less than 10 W. (auth)
Date: September 1, 1973
Creator: Thomas, S.W.; Carman, R.L.; Spracklen, H.R.; Tripp, G.R. & Coleman, L.W.
Partner: UNT Libraries Government Documents Department

Ultra-fast image converter streak cameras for laser fusion diagnostics

Description: The design and operation of a 10-ps resolution optical streak camera used to characterize laser pulses and other transient optical signals in fusion research is discussed. Performance characteristics are presented. The design, operation, and application of an x-ray streak camera used to study laser-produced plasmas in the x-ray spectral region of 1 to 10 keV with temporal and spatial resolutions of approximately 20 ps and approximately 10 $mu$m is also discussed. (auth)
Date: November 14, 1975
Creator: Houghton, J.W.; Thomas, S.W.; Attwood, D.T. & Coleman, L.W.
Partner: UNT Libraries Government Documents Department

Computer analysis of four channel x-ray microscopy images to obtain source and spectral emission data on laser fusion

Description: It is possible to analyze the images obtained from the four- channel x- ray microscope to obtain reasonable estimates of source spatial and energy emission. The technique shown here is particularly useful when relative comparisons are desired in which, from shot to shot, few parameters are changed. These data are of use in fuel pellet design and in checking design code predictions. The technique should also apply to pinhole camera data. Largest uncertainties appear to be due to film energy/handling calibration and mirror efficiency measurements. (auth)
Date: October 1, 1975
Creator: Harper, T.L.
Partner: UNT Libraries Government Documents Department

Electron density measurement of an electrostatically-confined, spherically symmetric, helium plasma using a microwave cavity resonance shift technique

Description: Thesis. Microwave resonant cavity frequency shift measurements are made to determine the electron density of an electrostatically confined, spherically symmetric helium plasma. Appropriate electron-density distribution functions are assumed and then used to relate the frequency shift to the central electron density. Results from electron injection, with currents of up to 200 mA, accelerating voltages from 100 to 450 V, and pressures of 5.0, 1.0, and 0.5 mTorr, suggest that a potential well is formed and that the minimum value of perveance required for well formation depends on the accelerating voltage and the pressure. Maximum electron densities of 9.5 x 10/sup 9//cm/sup 3/ are measured. Electron densities of 5.5 x 10/sup 9//cm/sup 3/ are measured during ion injection with currents of up to 20 mA at accelerating voltages between 0.5 kV and 5.0 kV and pressures of 5.0, 1.0, and 0.5 mTorr. Electron densities measured during ion injection show remarkable agreement with those predicted by an earlier theoretical model. (auth)
Date: August 1, 1973
Creator: Grush, W H
Partner: UNT Libraries Government Documents Department

Mechanical and optical coupling of a Thomson scattering laser T/sub e/ measurement to the ORMAK machine

Description: From 5th symposium on engineering problems of fusion research; Princeton, New Jersey, USA (6 Nov 1973). A combination laser, spectrometer device was constructed to observe the electron density and temperature of the ORMAK plasma by Thomson scattering in the range of 50 eV to 2 keV. The apparatus can observe the plasma at six radial positions and fire four 30-ns pulses of Q- switched ruby-laser light during an ORMAK shot. The apparatus and some of its optical components are described. (auth)
Date: January 1, 1973
Creator: Culver, J.S. & Murakami, M.
Partner: UNT Libraries Government Documents Department

2XII Thomson scattering system

Description: A Thomson-scattering system using a 6-joule Q-switched ruby laser and an eight-channel polychromator was constructed and employed to measure electron temperatures and densities at the center of the 2XII mirror confinement experiment. This report discusses experimental considerations used to guide design, construction, alignment, and operation of the Thomson-scattering system. (auth)
Date: December 1, 1973
Creator: Simonen, T.C.
Partner: UNT Libraries Government Documents Department