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Novel interferometer for the measurement of plasma density

Description: This report describes an interferometer recently developed and tested in prototype form. The device combines certain features of predecessor interferometers but in a module which is simpler to use, subject to limitations on path-length and bandwidth.
Date: March 1, 1977
Creator: Jacobson, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design for coordinated measurements of Faraday rotation and line-of-sight electron density using heterodyne techniques

Description: This report proposes a device which can overcome certain of the compromises of conventional Faraday rotation methods and at the same time measure the optical phase as well as the polarization. This would be useful for unfolding the Faraday rotation signal using the line-of-sight density along exactly the same path. Preliminary design parameters using a CO/sub 2/ laser are presented.
Date: July 1, 1977
Creator: Jacobson, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Parallel-beam correlation technique for measuring density fluctuations in plasmas with strong magnetic shear

Description: A laser diagnostic scheme is described which facilitates localization of density fluctuations along the line of sight. The method exploits both the generally observed anisotropy of density fluctuations in low-beta plasmas, as well as the twisting of the magnetic field which occurs across the minor diameter of reversed-field pinches, spheromaks, etc. Both interferometric and schlieren variations are discussed.
Date: April 1, 1981
Creator: Jacobson, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Eight-chord CO/sub 2/ interferometer for plasma-density measurements on ZT-40

Description: We describe a CO/sub 2/ laser interferometer which measures the path-integrated density along eight different chords simultaneously in the ZT-40 reversed-field pinch, a toroidal magnetic confinement experiment at Los Alamos. The interferometer system combines several reliable, commercially available components in a package which provides exceptional measurement resolution as well as ease of operation and maintenance.
Date: January 1, 1981
Creator: Jacobson, A. R. & Jolin, L. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transient phenomena on ZT-40

Description: Two aspects of fluctuations in the ZT-40 reversed-field pinch are examined. First, the polarization of the magnetic fluctuations in the outer (vacuum) region is discussed. This in turn provides information on the wavevectors associated with the turbulence. The results provide some clues about the location (in minor radius) of the singular surfaces which are customarily associated with fluctuations. Second, the density fluctuations are studied using a multichord interferometer. The spatial distr… more
Date: January 1, 1980
Creator: Jacobson, A. R. & Buchenauer, C. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observations of TEC fluctuations from an explosion on the Earth`s surface

Description: The authors report observations of perturbations in the ionosphere total electron content (TEC) caused by acoustic waves propagating from a large chemical explosion in souther New Mexico at the earth`s surface. Fluctuations in TEC were measured by two arrays of receivers that monitor the phase of the 136 MHz beacons on two geostationary satellites. One array, located in northern New Mexico, observed fluctuations in the region where acoustic waves from the blast impinged directly on the ionosphe… more
Date: September 1, 1994
Creator: Massey, R. S.; Carlos, R. C.; Jacobson, A. R. & Wu, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Global optical lightning flash rates determined with the Forte satellite

Description: Using FORTE photodiode detector (PDD) observations of lightning, we have determined the geographic distribution of nighttime flash rate density. We estimate the PDD flash detection efficiency to be 62% for total lightning through comparison to lightning observations by the TRMM satellite's Lightning Imaging Sensor (LIS), using cases in which FORTE and TRMM viewed the same storm. We present here both seasonal and l,ot,al flash rate maps. We examine some characteristics of the optical emissions o… more
Date: January 1, 2003
Creator: Light, T. (Tracy E.); Davis, S. M. (Sean M.); Boeck, W. L. (William L.); Jacobson, A. R. & Suszcynsky, D. M. (David M.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Four years of operations and results with FORTE

Description: The FORTE (Fast Onboard Recording of Transient Events) satellite was launched on 29 August 1997 and has been in continuous operation since that time. FORTE was placed in a nearly circular, 825-km-altitude, 70 degrees inclination orbit by a Pegasus rocket funded by Air Force Space Test Program. The Department of Energy funded the FORTE satellite, which was designed and built at Los Alamos. FORTE's successful launch and engineered robustness were a result of several years of dedicated work by the… more
Date: January 1, 2001
Creator: Klingner, Phillip L.; Carlson, Leslie D.; Dingler, Robert D.; Esch-Mosher, D. M. (Diana M.); Jacobson, A. R. & Roussel-Dupre, D. (Diane)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thunderstorm and Lightning Studies using the FORTE Optical Lightning System (FORTE/OLS)

Description: Preliminary observations of simultaneous RF and optical emissions from lightning as seen by the FORTE spacecraft are presented. RF/optical pairs of waveforms are routinely collected both as individual lightning events and as sequences of events associated with cloud-to-ground (CG) and intra-cloud (IC) flashes. CG pulses can be distinguished from IC pulses based on the properties of the RF and optical waveforms, but mostly based on the associated RF spectrograms. The RF spectrograms are very sim… more
Date: February 1, 1999
Creator: Argo, P.; Franz, R.; Green, J.; Guillen, J. L.; Jacobson, A. R.; Kirkland, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scaling of sustained ZT-40 M reversed field pinches

Description: Experiments aimed at evaluating the scaling properties of the ZT-40M Reversed-Field Pinch (RFP) facility were conducted in 1983 at Los Alamos. Sustained discharges were produced at nominal toroidal currents ranging from 60 to 240 kA. The standard fill pressure was kept close to the lower limit of the usable pressure range, and the scaling data were acquired at a fixed time in the discharges while the plasma was in a quasi-steady state. Scalings of the diameter-averaged electron density, electro… more
Date: December 1, 1993
Creator: Graham, J.; Haberstich, A.; Baker, D. A.; Buchenauer, C. J.; Caramana, E. J.; DiMarco, J. N. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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