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in subjects: "Cyclotron Resonance"

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Status of ECR (Electron Cyclotron Resonance) source technology

ECR (Electron Cyclotron Resonance) ion sources are now in widespread use for the production of high quality multiply charged ion beams for accelerators and atomic physics experiments, and industrial applications are being explored. Several general characteristics of ECR sources explain their widespread acceptance. For use with cyclotrons which require CW multiply charged ion beams, the ECR source has many advantages over heavy-ion PIG sources. Most important is the ability to produce higher cha… more

Date: March 1, 1987

Creator: Lyneis, C.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Alpha Heating in ITER L-mode and H-mode Plasma

There are many uses of predictions of ITER plasma performance. One is assessing requirements of different plasma regimes. For instance, what current drive and control are needed for steady state. The heating, current drive, and torque systems planned for initial DT operation are negative ion neutral beam injection (NB), ion cyclotron resonance (IC), and electron cyclotron resonance (EC). Which combinations of heating are optimal. What are benefits of the torques, current drive, and fueling usin… more

Date: July 18, 2011

Creator: Budny, R.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Crossed Sightline ECE Diagnostics

It was shown that crossed-sightline ECE (electron-cyclotron-emission) can be used for both local measurement of fluctuating quantities (electron temperature and density), and also for inferring the local value of the absolute magnetic field in present experiments, or in a reactor environment. The absolute magnetic field measurement is a direct measure of the local plasma pressure ([beta]) in currentless devices, and in combination with temperature and pressure measurements is a measurement of t… more

Date: September 8, 1990

Creator: Thomas, C. E., Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Cyclotron Resonance and Quasiparticles

This introductory paper contains personal perspectives about the importance of cyclotron resonance in forming our modern view of solids. The papers following this one will discuss the discovery, refinements, and some of the latest developments. Although I will touch on some of these subjects, I leave the details to the other authors and in the main focus on the conceptual impact of the work. I propose that it was experiments based on cyclotron resonance which established the quasiparticle conce… more

Date: January 15, 2005

Creator: Cohen, Marvin L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Experimental studies of auroral arc generators

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). An all-sky video camera system was deployed in Eagle, Alaska at the foot of the magnetic field line that threads geosynchronous satellite 1989-046 as part of a campaign to study correlations of ground-based auroral activity with satellite-based plasma and energetic particle measurements. The overall intent of the project was to study magnetosphere-i… more

Date: August 1, 1997

Creator: Suszcynsky, D. M.; Borovsky, J. E. & Thomsen, M. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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PLASMA INSTABILITIES AND WAVES EXCITED BY AN ANISOTROPIC ENERGY DISTRIBUTION PRODUCED BY ELECTRON CYCLOTRON RESONANCE. Quarterly Progress Report No. 9.

No Description Available.

Date: January 1, 1969

Creator: Shohet, J.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effect of resonant microwave power on a PIG ion source. Revision

We have investigated the effect of applying microwave power at the electron cyclotron frequency on the characteristics of the ion beam extracted from a hot-cathode PIG ion source. No change was seen in the ion charge state distribution. A small but significant reduction in the beam noise level was seen, and it is possible that the technique may find application in situations where beam quiescence is important. 32 refs., 2 figs.

Date: August 1, 1984

Creator: Brown, I.G.; Galvin, J.E.; Gavin, B.F. & MacGill, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Source options for RHIC

Conceptual designs of the RHIC facility are matched to the parameters of existing tandem Van de Graaff accelerators at Brookhaven National Laboratory. It has been shown that tandems could produce many ion species up to gold with sufficient intensities for injection into the BNL booster and further acceleration and storage in AGS and RHIC synchrotrons. There have been, however, questions about the long-term performance of tandem accelerators, in view of their reliability, cost of maintenance, an… more

Date: January 1, 1988

Creator: Prelec, K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Modeling the shell type TeV supernove remnant RX J1713-3946

We simulate the shock waves of shell type supernova remnants with a prototype progenitor of 15 M{sub {circle_dot}} and fit the size and lifetime of SNR RX J1713-3946 with a density of {approx} 1O{sup -26}g cm{sup -3} for the shocked downstream plasma. Such a density is required for efficient stochastic electron acceleration and leads to a thermal X-ray flux more than one order of magnitude lower than the observed featureless X-ray flux. Fast mode waves must be excited to have efficient stochast… more

Date: January 1, 2009

Creator: Fryer, Christopher Lee; Fan, Zhonghui & Liu, Siming

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ion source studies at the ORNL ECR source facility

Using high resolution magnetic analysis, we have measured energy spreads of Ar/sup +q/ (1 < q < 12) ion beams extracted from the ORNL ECR ion source under a number of different ECR plasma conditions. The measured energy spreads for the different charge states fall in the range 8 to 20 eV per charge and are all roughly proportional to the ion charge. In addition, we have used a combination of magnetic and electrostatic analysis to investigate the high charge state tail of the extracted Ar/sup +q… more

Date: January 1, 1989

Creator: Meyer, F.W. & Hale, J.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status of the ATLAS Positive-Ion Injector Project

The goal of the Argonne Positive Ion Injector project is to replace the ATLAS tandem injector with a facility which will increase the beam currents presently available by a factor of 100 and to make available at ATLAS essentially all beams including uranium. The beam quality expected from the facility will be at least as good as that of the tandem based ATLAS. The project combines two relatively new technologies - the electron cyclotron resonance ion source, which provides high charge state ion… more

Date: January 1, 1987

Creator: Pardo, R. C.; Benaroya, R.; Billquist, P. J.; Bollinger, L. M.; Clifft, B. E.; Den Hartog, P. K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Operation of the ORNL ECR (Electron Cyclotron Resonance) source

The ORNL ECR multicharged ion source, dedicated for studying the atomic physics interactions of multicharged ions with atoms, ions, electrons, and surfaces has been in operation since 1984. High charge state ion beams ranging from fully stripped light ions (up to Ne) to up to 40% stripped heavy ions (A approx. 200) have bee produced. Ion beams of the metallic elements developed to date include Cr, Fe, Ni, Ta, and Au, and are obtained by the use of a solid feed technique.

Date: January 1, 1987

Creator: Meyer, F.W. & Hale, J.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Optically pumped polarized ion sources

Recent operating experience and development of the Optically Pumped Polarized Ion Source (OPPIS) projects at LAMPF and other laboratories is reviewed. 11 refs., 4 figs., 1 tab.

Date: January 1, 1991

Creator: van Dyck, O.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Characteristics of the ORNL ECR multipole plasma source

There are many similarities between the characteristics of the plasma sources needed for semi-conductor processing and those needed for fusion neutral beams. Both need useful plasma areas up to 20-30 cm in diameter and uniform plasma densities (<10% variation for fusion with a factor of about three better needed for semiconductor processing). The evolution of fusion ion sources suggested a development strategy for improved semiconductor processing sources. The first step in this path has now be… more

Date: January 1, 1989

Creator: Berry, L.A.; Gorbatkin, S.M.; Roberto, J.B.; Tsai, C.C.; Holber, W. & Yeh, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Improved system for perpendicular electron-cyclotron emission measurements on TMX-Upgrade

Perpendicular electron-cyclotron emission (PECE) is used on TMX-U to diagnose thermal-barrier hot electrons (T/sub H/ approx. 100 to 400 keV); yielding the time history of the temperature of these relativistic electrons. We describe an improved quasi-optical viewing system for these measurements that uses high sensitivity superheterodyne receivers at fixed frequencies of 60, 98, 130, and 196 GHz. The improved viewing and transport system consists of an off-axis ellipsoidal mirror that images th… more

Date: March 7, 1986

Creator: Lasnier, C. J.; Ellis, R. F. & James, R. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Synchrotron injectors based on high charge state ion sources

The performance of any injector contemplated to replace the electrostatic tandem accelerators some time in the future should evidently match or surpass the characteristics of the tandems. It is a fortunate coincidence that the performance of the BNL tandem satisfies in most respects the requirements of the proposed collider, although originally tandems were not built with this application in mind. Requests for heavy ion beams with parameters suitable for injection into the rings of a heavy ion … more

Date: February 14, 1990

Creator: Prelec, K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Comparison of dry-etch techniques for GaN, InN, and AlN

FABRICATION OF GROUP III NITRIDE DEVICES RELIES ON THE ABILITY TO PATTERN FEATURES TO DEPTHS RANGING FROM 1000 A TO {gt} 5 MICRONS WITH ANISOTROPIC PROFILES, SMOOTH MORPHOLOGIES, SELECTIVE ETCHING OF ONE MATERIAL OVER ANOTHER, AND A LOW DEGREE OF PLASMA INDUCED DAMAGE. IN THIS STUDY, GAN ETCH RATES AND ETCH PROFILES ARE COMPARED USING REACTIVE ION ETCH (RIE), REACTIVE ION BEAM ETCHING (RIBE), ELECTRON CYCLOTRON RESONANCE (ECR), AND INDUCTIVELY COUPLED PLASMA (ICP) ETCH SYSTEMS. RIE YIELDED THE … more

Date: December 1, 1997

Creator: Shul, R. J.; Vawter, G. A.; Willison, C. G.; Bridges, M. M.; Lee, J. W.; Pearton, S. J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Concluding remarks for ECRIS '02

ECRIS'02 was held in Jyvaeskylae Finland at the edge of Lake Jyvaeskylae, which was beautiful location to meet and discuss the state of Electron Cyclotron Resonance ion sources. It was the 15th ECR Ion Source Workshop in a series stretching back to the first workshop held November 6, 1978 in Karlsruhe Germany. Overall, the workshop reports could be characterized as showing solid achievements and steady progress without any spectacular breakthroughs or highly controversial new ideas. In this sho… more

Date: September 9, 2002

Creator: Lyneis, Claude

Item Type: Article

Partner: UNT Libraries Government Documents Department

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FT-ICR mass spectrometry of very highly charged atomic ions

The authors report FT-ICR measurements of samples trapped in the electron beam ion trap (EBIT) at Livermore. They made use of the access provided by the radial x-ray slots. They constructed two probes that could be inserted into the 2-mm wide slots. The probes each subtend only 25{degree} and face each other 180{degree} apart. They show a typical transformed spectrum of highly charged {sup 84}Kr ions obtained with this system. The spectrum was obtained by exciting with a 300-{mu}s sweep from 17… more

Date: May 15, 1995

Creator: Schweikhard, L.; Beck, B. & Beiersdorfer, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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ICRF heating on helical devices

Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results… more

Date: September 1, 1995

Creator: Rasmussen, D.A.; Lyon, J.F. & Hoffman, D.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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ICRF heating on helical devices

Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7-AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Result… more

Date: September 1, 1995

Creator: Rasmussen, D. A.; Lyon, J. F.; Hoffman, D. J.; Murakami, M.; England, A. C.; Wilgen, J. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design options for an ITER ion cyclotron system

Recent changes have occurred in the design requirements for the ITER ion cyclotron system, requiring in-port launchers in four main horizontal ports to deliver 50 MW of power to the plasma. The design is complicated by the comparatively large antenna-separatrix distance of 10--20 cm. Designs of a conventional strap launcher and a folded waveguide launcher than can meet the new requirements are presented.

Date: September 1, 1995

Creator: Swain, D. W.; Baity, F. W.; Bigelow, T. S.; Ryan, P. M.; Goulding, R. H.; Carter, M. D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design of fast tuning elements for the ITER ICH system

The coupling between the ion cyclotron (IC) antenna and the ITER plasma (as expressed by the load resistance the antenna sees) will experience relatively fast variations due to plasma edge profile modifications. If uncompensated, these will cause an increase in the amount of power reflected back to the transmitter and ultimately a decrease in the amount of radio frequency (rf) power to the plasma caused by protective suppression of the amount of rf power generated by the transmitter. The goals … more

Date: May 1, 1996

Creator: Swain, D. W. & Goulding, R. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A new 14 GHz Electron-Cyclotron-Resonance Ion Source (ECRIS) for the heavy ion accelerator facility ATLAS

A 14 GHz Electron-Cyclotron-Resonance Ion Source (ECRIS) has been designed and built at Argonne National Laboratory. The source is a modification of the AECR at Berkeley and incorporates the latest results from ECR developments to produce intense beams of highly charged ions, including an improved magnetic confinement of the plasma electrons with an axial mirror ratio of 3.5. The aluminum plasma chamber and extraction electrode as well as a biased disk on axis at the microwave injection side do… more

Date: November 1997

Creator: Schlapp, M.; Pardo, R. C.; Vondrasek, R. C.; Billquist, P. J. & Szczech, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department