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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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Development of a low intensity current monitor system

Description: This report documents the development of a current transformer system used to measure pulsed ion beam currents with a wide dynamic intensity range (nA to mA, and factor of 10{sup 6}). Peak beam currents at the LAMPF accelerator typically range from 100 to nA to 40 mA with pulse widths varying from 30 to 1000 {mu}s. Signal conditioning of the peak current output provides an average current readout with a range of 1 nA to 2 mA, noise of approximately {plus minus}0.5 nA, and accuracy of {plus minu… more
Date: January 1, 1991
Creator: Gallegos, F.R.
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Partner: UNT Libraries Government Documents Department
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Fiber optics and microprocessors: a control-system solution for the laser-fusion environment

Description: The use of fiber optics and microprocessors in a distributed computer control system for a 100-kJ CO/sub 2/ laser fusion facility is described. Gas-laser control systems must operate in an environment in which megavolt Marx circuits generate megampere discharges in the laser amplifiers, with attendant high electromagnetic fields. By linking the distributed controls with fiber optics the adverse effect of these fields on the hard-wired controls is mimimized, and the additional advantage of groun… more
Date: January 1, 1978
Creator: Thuot, M.E.
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Partner: UNT Libraries Government Documents Department
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Preliminary measurements of gamma ray effects on characteristics of broad-band GaAs field-effect transistor preamplifiers

Description: The effect of gamma radiation on electrical characteristics of cryogenically cooled broad-band low-noise microwave preamplifiers has been preliminarily evaluated. The change in the gain and noise figure of a 1-2 GHz preamplifier using GaAs microwave transistors was determined at gamma doses between 10/sup 5/ rad to 5 /times/ 10/sup 8/ rad. The gain and noise figure was measured at ambient temperatures of 300 K and 80 K. 8 refs., 2 figs.
Date: January 1, 1985
Creator: Jackson, H.G.; Shimizu, T.T. & Leskovar, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fusion development and technology

Description: This report discusses the following: superconducting magnet technology; high field superconductors; advanced magnetic system and divertor development; poloidal field coils; gyrotron development; commercial reactor studies--aries; ITER physics: alpha physics and alcator R D for ITER; lower hybrid current drive and heating in the ITER device; ITER superconducting PF scenario and magnet analysis; ITER systems studies; and safety, environmental and economic factors in fusion development.
Date: January 1, 1992
Creator: Montgomery, D.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A novel charge sensitive preamplifier without the feedback resistor

Description: A novel charge sensitive preamplifier which has no resistor in parallel with the feedback capacitor is presented. No external device or circuit is required to discharge the feedback capacitor. The detector leakage and signal current flows away through the gate of the first JFET which works with its gate to source junction slightly forward biased. The DC stabilization of the preamplifier is accomplished by an additional feedback loop, which permits to equalize the current flowing through the for… more
Date: January 1, 1992
Creator: Bertuccio, G. (Politecnico di Milano, Milan (Italy). Dipt. di Elettronica e Informazione); Rehak, P. & Xi, D. (Brookhaven National Lab., Upton, NY (United States))
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Partner: UNT Libraries Government Documents Department
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Charged particle detector system for ISABELLE spectrometers

Description: A detector system combining the good time resolution and low dead time of PWC's and the good space resolution of drift chambers is proposed for use in ISABELLE spectrometers. Central to this detector is the development of two integrated electronic circuit systems. The detectors are described with special emphasis on the electronic systems. The detector system proposed will be capable of handling particle flux rates typical of conventional PWC's yet providing a spacial resolution of 100 ..mu..m.… more
Date: January 1, 1977
Creator: Platner, E.D.
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Partner: UNT Libraries Government Documents Department
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Development program for a 200 kW, CW gyrotron. Quarterly report No. 3, January-March 1980

Description: The objective of this program is the design and development of a millimeter-wave device to produce 200 kW of continuous-wave power at 60 GHz. The device, which will be a gyrotron oscillator, will be compatible with power delivery to an electron-cyclotron plasma. Smooth control of rf power output over a 17 dB range is required, and the device should be capable of operation into a severe time-varying rf load mismatch. The duration of the program is 36 months, to encompass the building and test up… more
Date: January 1, 1980
Creator: Arnold, K.W.; Tancredi, J.J.; Caplan, M.; Ha, K.W.; Birnbaum, D.N. & Weiss, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rf power sources for 1990 and beyond

Description: This paper will discuss the types of devices and system architectures that show promise in providing rf power sources for future space requirements. It will extrapolate these solutions to accelerators that are now being planned for construction and commissioning in the 1990s and will suggest technological advantages of using SDI-developed rf systems. Finally, the present state of the various SDI-sponsored high-powered rf-development programs will be reviewed.
Date: January 1, 1986
Creator: Reid, D.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Millimeter wave free electron laser amplifiers: Experiments and designs

Description: Free electron laser amplifies are investigated as sources of high- average-power (1 MW) millimeter to submillimeter wave radiation (200 GHz - 600 GHz) for application to electron cyclotron resonance heating of magnetically confined fusion plasmas. As a stepping-stone to higher frequencies and cw operation a pulsed amplifier ({tau}{sub pulse} {approx equal} 80 ns) at 98 GHz is being developed. Status is reported on this experiment which investigates linear gain amplification with use of sheet el… more
Date: January 1, 1991
Creator: Bidwell, S. W.; Zhang, Z. X.; Antonsen, T. M., Jr.; Bensen, D. M.; Destler, W. W.; Granatstein, V. L. et al.
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Partner: UNT Libraries Government Documents Department
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Ceramic vacuum tubes for geothermal well logging

Description: Useful design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes are discussed for application to the development of high temperature well logs. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data are presented in the appendix.
Date: January 1, 1977
Creator: Kelly, R.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development program for a 200 kW, CW gyrotron. Quarterly report No. 2, October-December 1979

Description: The objective of this program was the design and development of a millimeter-wave device to produce 200 kW of continuous-wave power at 110 GHz. The device, which will be a gyrotron oscillator, will be compatible with power delivery to an electron-cyclotron plasma. Smooth control of rf power output over a 17 dB range is required, and the device should be capable of operation into a severe time-varying rf load mismatch. During the middle of this report period, the operating frequency was changed … more
Date: January 1, 1979
Creator: Arnold, K.W.; Tancredi, J.J.; Caplan, M.; Ha, K.W.; Birnbaum, D.N. & Weiss, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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First 200 kW CW operation of a 60 GHz gyrotron

Description: The gyrotron is a microwave tube which employs the electron cyclotron maser interaction to produce high power output at millimeter wavelengths. It has important and growing applications for heating of plasmas in controlled thermonuclear fusion experiments. The Varian 60 GHz gyrotron has recently generated microwave power in excess of 200 kW during CW operation, wth excellent dynamic range and operating stability. This is the highest average power ever produced by a microwave tube in the millime… more
Date: January 1, 1983
Creator: Jory, H.; Bier, R.; Evans, S.; Felch, K.; Fox, L.; Huey, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final analysis of the engineering data on the scyllac feedback stabilization experiment

Description: The feedback stabilization system consists of four basic components: plasma position detectors, a signal processor or mode analyzer driven by the position detector signals, power amplifiers which are driven by the mode analyzer, and feedback load coils driven by the power amplifiers. A short description of each of the four components of the system is presented. The location of the components in the experiment is shown.
Date: January 1, 1977
Creator: Kutac, K. J.; Kewish, R. W.; Miller, G. & Gribble, R. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Charged particle detector system for high rate experiments

Description: A charged particle detector system under development at BNL for use at the Multiparticle Spectrometer (MPS) and eventually at ISABELLE is described. The object is to take full advantage of the position accuracy, resolving time and instantaneous rate capabilities of narrow anode spacing drift-proportional chambers. The system will have position resolution sigma approximately equal to 100..mu.., time resolution approximately equal to 8 ns, detector sensitive time approximately equal to 50 ns, and… more
Date: January 1, 1977
Creator: Platner, E D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Overmoded waveguide components for the ECH system on PDX

Description: Waveguide components designed specifically for transmitting power into PDX for electron cyclotron heating (ECH) at 60 GHz are described. These include mode converters from the circular electric TE01 mode to the polarized HE11 mode, compact corrugated waveguide bends with a hyperbolic secant curvature variation, compact corrugated waveguide diameter tapers with a parabolic profile, and a high voltage dc break incorporating a section of dielectric waveguide, all designed for low-loss HE11 propaga… more
Date: January 1, 1984
Creator: Doane, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microwave generation for magnetic fusion energy applications

Description: This progress report encompasses work on two separate projects, both related to developing sources for electron cyclotron resonance heating of magnetic fusion plasmas. The report is therefore divided into two parts as follows: Free electron laser with small period wigglers; and theory and modeling of high frequency, high power gryotron operation. Task A is experimental and eventually aims at developing continuously tunable, cw sources for ECRH with power per unit as high as 5 megawatts. Task B … more
Date: January 1, 1992
Creator: Antonsen, T. M. Jr.; Destler, W. W.; Granatstein, V. L. & Levush, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proportional chambers and multiwire drift chambers at high rates

Description: The high event and particle rates expected for ISABELLE intersecting storage rings raise the question whether PWC's and drift chambers, now widely in use in experiments, still can operate under such conditions. Various effects depend on the number of avalanches produced per length of wire N and the size of the avalanche Q, i.e., on the number of positive ions created in an avalanche. Therefore the important parameter for the following discussion is the product QN. The minimum Q is determined by… more
Date: January 1, 1977
Creator: Walenta, A.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Class of deflection-modulated, high-power microwave amplifiers

Description: An unusual deflection-modulated, fast-wave electron device is analyzed. It has several unique properties; the electron beam is unbunched and is perpendicular to the direction of power flow in the circuit, and the circuit could be a simple fundamental-mode rectangular waveguide. The amplifier consists of an electron gun, a deflection cavity, an optional beam-bending system, and an output interaction region. An idealized theory showing that 100 percent electronic efficiency may be achieved, and s… more
Date: January 1, 1977
Creator: Tallerico, P.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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60 GHz and 110 GHz development program. Quarterly report No. 2, October-December 1979

Description: The objective of this program has been changed from developing a microwave amplifier or oscillator capable of producing 200 kW cw power output at 110 GHz to developing families of microwave oscillators capable of producing 200 kW of peak power output at 60 GHz and some higher frequency, possibly 90 GHz or 110 GHz, with pulse durations at 100 ms, 30 s and cw. The use of cyclotron resonance interaction is being pursued. The early design phases of this program are discussed.
Date: January 1, 1979
Creator: Shively, J.; Conner, C.; Jory, H.; Stone, D.; Symons, R.; Thomas, G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development program for a 200 kW, CW, 110 GHz gyrotron. Quarterly report No. 1, June-September 1979

Description: The objective of this program is the design and development of a millimeter-wave device to produce 200 kW of continuous-wave power at 110 GHz. The device, which will be a gyrotron oscillator, will be compatible with power delivery to an electron-cyclotron plasma. Smooth control of rf power output over a 17 dB range is required, and the device should be capable of operation into a severe time-varying rf load mismatch. Progress toward this goal is described and specifications of the gyrotron are … more
Date: January 1, 1979
Creator: Arnold, K.W.; Tancredi, J.J.; Caplan, M.; Ha, K.W.; Birnbaum, D.N. & Weiss, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Conversion of power and frequency

Description: This paper deals with a novel idea to excite electrons to radiate energy in the short (millimeter) wavelength range. A short electron bunch is made to travel along the axis of a waveguide where a TM electromagnetic wave is also traveling and causes the beam to perform transverse oscillations. The electrons radiate energy as a consequence of the oscillations. It is found that a convenient mode of operation is to drive the waveguide in proximity of the cut-off.
Date: January 1, 1992
Creator: Ruggiero, A. G. & Wei, J.
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Partner: UNT Libraries Government Documents Department
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Subpicosecond high-brightness uv laser system

Description: A laser system that produces intense subpicosecond pulses of 248 nm light is under development. Ultrashort pulses are generated in the visible in a synchronously-pumped mode-locked dye oscillator, heterodyned into the uv by two KDP crystals, and amplified in a chain of KrF* amplifiers. Front end output of 5 ..mu..J is amplified to 20 mJ and focused to peak intensities of order 10/sup 17/ W cm/sup -2/. Additional amplification is expected to permit experiments at intensities >10/sup 20/ W cm/sup… more
Date: January 1, 1986
Creator: Gibson, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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