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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

Description: This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Las… more
Date: September 1, 1991
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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INEX simulations of the optical performance of the AFEL

Description: The AFEL (Advanced Free-Electron Laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high-brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf-linac. Initial laser experiments will be performed with a 1-cm-period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 {mu}m. Future experiments will operate with slotted-tube'' electromagnetic wiggle… more
Date: January 1, 1991
Creator: Goldstein, J.C.; Wang, T.S.F. & Sheffield, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice

Description: The number of emitted photons that can be obtained from a fluorophore increases with the incident light intensity and the duration of illumination. However, saturation of the absorption transition and photodestruction place natural limits on the ultimate signal-to-noise ratio that can be obtained. Equations have been derived to describe the fluorescence-to-background-noise ratio in the presence of saturating light intensities and photodestruction. The fluorescence lifetime and the photodestruct… more
Date: 1989
Creator: Mathies, R. A.; Peck, K. & Stryer, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fueling of tandem mirror reactors

Description: This paper summarizes the fueling requirements for experimental and demonstration tandem mirror reactors (TMRs), reviews the status of conventional pellet injectors, and identifies some candidate accelerators that may be needed for fueling tandem mirror reactors. Characteristics and limitations of three types of accelerators are described; neutral beam injectors, electromagnetic rail guns, and laser beam drivers. Based on these characteristics and limitations, a computer module was developed fo… more
Date: January 1, 1985
Creator: Gorker, G. E. & Logan, B. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Generation of coherent soft x-rays using a single-pass free-electron laser amplifier

Description: We consider a single-pass free-electron laser (FEL) amplifier, driven by an rf-linac followed by a damping ring for reduced emittance, for use in generating coherent light in the soft x-ray region. The dependence of the optical gain on electron-beam quality, studied with the three-dimensional FEL simulation code FELEX, is given and related to the expected power of self-amplified spontaneous emission. We discuss issues for the damping ring designed to achieve the required electron beam quality. … more
Date: January 1, 1987
Creator: Wang, T. F.; Goldstein, J. C.; Newmam, B. E. & McVey, B. D.
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Partner: UNT Libraries Government Documents Department
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Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

Description: High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertur… more
Date: October 28, 1985
Creator: Eimerl, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimates of SASE power in the short wavelength region

Description: Given a sufficiently bright electron beam, the self-amplified-spontaneous emission (SASE) can provide gigawatts of short wavelength coherent radiation. The advantages of SASE approach are that is requires neither optical cavity nor an imput seed laser. In this note, we estimate the peak power performance of SASE for wavelengths shorter than 1000 {Angstrom}. At each wavelength, we calculate the saturated power from a uniform parameter undulator and the enhanced power from a tapered undulator. Th… more
Date: March 1, 1992
Creator: Kim, Kwang-Je.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CW 100MW microwave power transfer in space

Description: A proposal is made for high-power microwave transfer in space. The concept consists in a microwave power station integrating a multistage microwave free-electron laser and asymmetric dual-reflector system. Its use in space is discussed. 9 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Takayama, K. (Houston Univ., TX (United States). Inst. for Beam Particle Dynamics National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan) Texas Accelerator Center, The Woodlands, TX (United States)); Hiramatsu, S. (National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)) & Shiho, M. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser annealing of ion implanted CZ silicon for solar cell junction formation. Quarterly report No. 2

Description: Results on a contract to evaluate the merits of large spot size pulsed laser annealing of ion implanted silicon wafers for junction formation in solar cells are reported. Investigations on homogenization of the laser beam were continued. In addition to the 30 mm diameter fused silica rod with a 90/sup 0/ bend configuration, quartz tubes were obtained and briefly tried. Best results were obtained with the rod homogenizer. Laser annealing experimentation resulted in complete recrystallization of … more
Date: October 1, 1980
Creator: Katzeff, J. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole channel

Description: This work studies the electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole field for a free-electron laser (FEL) that will be operated in the VUV or XUV wavelength region. The quadrupole field is assumed to vary continuously along the symmetry axis. The linearized equations of electron motion are solved analytically by using the two-scale perturbation method for a plane polarized wiggler. The electron-beam envelopes and the envelope equations, as well … more
Date: January 1, 1985
Creator: Wang, T. F. & Cooper, R. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combination free-electron and gaseous laser

Description: A multiple laser having one or more gaseous laser stages and one or more free electron stages is described. Each of the free electron laser stages is sequentially pumped by a microwave linear accelerator. Subsequently, the electron beam is directed through a gaseous laser, in the preferred embodiment, and in an alternative embodiment, through a microwave accelerator to lower the energy level of the electron beam to pump one or more gaseous lasers. The combination laser provides high pulse repet… more
Date: June 8, 1981
Creator: Brau, C. A.; Rockwood, S. D. & Stein, W. E.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Investigation of induced unimolecular decomposition for development of visible chemical lasers. Final report, 1 May 1976--30 April 1977

Description: This report summarizes the results of a study of azide decomposition for possible application in a visible chemical laser. Task 1 of the subject contract involved thorough review of the chemical literature pertaining to azide decomposition. Covalently bonded azides decompose directly into an electronically excited nitrene (RN) and ground-state molecular nitrogen. Ionic azides decompose to metal atoms and azide radicals. The azide radicals subsequently recombine to form electronically excited ni… more
Date: May 1, 1977
Creator: Piper, L G & Taylor, R L
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of mesoscopic physics

Description: This report discusses the following topics: Acoustical nondestructive evaluation of heterogeneous materials in the multiple scattering regime. Classical and quantum superdiffusion in a time-dependent random potential. Negative Magnetoresistance in Variable Range Hopping Conduction. Reproducible Conductance Fluctuations in Macroscopic Anderson Insulators. Feasibility of far-infared lasers using multiple semiconductor quantum wells.
Date: January 1, 1992
Creator: Feng, Shechao.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Feasibility of laser pumping with neutron fluxes from present-day large tokamaks

Description: The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser lines most readily pumped are probably the /sup 3/He-Ne lines at 0.633 ..mu.. and in the infrared, where the /sup 3/He-Ne gas is excited by energetic ions produced in the /sup 3/He(n,p)T reaction. These lines are expected to lase at the levels of D-T neutron flux foreseen … more
Date: August 1, 1986
Creator: Jassby, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phoenix I energy extraction experiment

Description: Energy extraction experiments are reported for the Phoenix I amplifier driven by a discharge-initiated oscillator-preamplifier system operating on mixtures of either SF/sub 6/-HI or SF/sub 6/-C/sub 2/H/sub 6/ and an electron-beam-initiated intermediate amplifer (lambda-3) fueled with H/sub 2/ and F/sub 2/ mixtures. When the oscillator-preamplifier system operated with mixtures of SF/sub 6/-HI the input spectrum to the Phoenix I amplifier contained approx. 28 P-branch vibrational-rotational line… more
Date: July 1, 1980
Creator: Hoffman, J. M.; Patterson, E. L.; Tisone, G. C. & Moreno, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/(YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 2/ (Ruby), a study of certain properties of these laser materials related to their valence-electron structures

Description: A direct method of determination of the valence-electron structure from its crystal structure has been presented by the writer at XIIth International Congress of Crystallography, at Ottawa, 1981. Here the method is applied to determine the valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/ (YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ (ruby) to see how certain properties of these laser materials are related to their valence-electron structures. The first point observed is the very stron… more
Date: January 1, 1982
Creator: Yu, S. H. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electron heating and confinemet measurements in EBT-S using Thomson scattering

Description: Thomson scattering of ruby laser light was used to measure electron temperatures and densities in the ELMO Bumpy Torus-Scale (EBT-S) at Oak Ridge National Laboratory. The measurements were made primarily during May 1980, although some were taken during January 1980. The scattering system, which was designed for very low electron density measurements, features a 14-J ruby laser, a high-throughput spectrometer, and 15% quantum efficiency photomultipliers. The measured electron densities lie in th… more
Date: September 1, 1980
Creator: Bighel, L. & Cobble, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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RIMS diagnostics for laser desorption/laser ablation

Description: Laser desorption mass spectrometry is a useful method for interrogating materials and events at or near surfaces. Laser desorption/ablation combined with Resonance Ionization Mass Spectrometry (RIMS) provides a powerful tool to obtain information on chemical composition and speciation and, in some cases, internal and translational energy distributions. The application of this technique to the interrogation of materials and interfaces is discussed for several systems, including the analysis of c… more
Date: January 1, 1986
Creator: Apel, E. C.; Nogar, N. S.; Miller, C. M. & Estler, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proposed research on advanced accelerator concepts

Description: This report summarizes technical progress and accomplishments during the proposed three-year research on advanced accelerator concepts supported by the Department of Energy under Contract No. DE-FG02-88ER40465. A vigorous theoretical program has been pursued in critical problem areas related to advanced accelerator concepts and the basic equilibrium, stability, and radiation properties of intense charged particle beams. Broadly speaking, our research has made significant contributions in the fo… more
Date: September 1, 1991
Creator: Davidson, R.C. & Wurtele, J.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical-scattering measurements from 1. 06-. mu. m, 0. 53-. mu. m, and 0. 35-. mu. m laser-heated disk targets

Description: A discussion is presented on scattered light measurements relevant to three of the important parametric instabilities which occur in high intensity laser plasma interactions: stimulated Brillouin scattering (SBS), the two plasmon decay instability (2-..omega../sub pe/), and stimulated Raman scattering (SRS). Most of these experiments were carried out on the ARGUS facility. Its configuration is described for the multiple wavelength experiments, all of which were conducted with one beam illuminat… more
Date: January 1, 1982
Creator: Turner, R. E.; Campbell, E. M.; Phillion, D. W.; Mead, W. C.; Ze, F.; Max, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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