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Book Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver

Download or read book Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm2 was obtained under the same conditions that gave 57 45 mA/cm2 of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl− was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm2, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

Book Evaluation of Negative Ion Beam Driver Concepts for Heavy Ion Fusion

Download or read book Evaluation of Negative Ion Beam Driver Concepts for Heavy Ion Fusion written by L. R. Grisham and published by . This book was released on 2002 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Evaluation of Negative Ion Beam Driver Concepts for Heavy Ion Fusion

Download or read book Evaluation of Negative Ion Beam Driver Concepts for Heavy Ion Fusion written by L. R. Grisham and published by . This book was released on 2002 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Proof of concept Experiments for Negative Ion Driver Beams Forheavy Ion Fusion

Download or read book Proof of concept Experiments for Negative Ion Driver Beams Forheavy Ion Fusion written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Negative halogen ion beams have recently been proposed as heavy ion fusion drivers. They would avoid the problem of electron accumulation in positive ion beams, and could be efficiently photodetached to neutrals if desired [1]. Initial experiments using chlorine produced a current density of 45 mA/cm2 of 99.5% atomic negative Cl with an e/Cl− ratio as low as 7:1 and good emittance.

Book Development and Applications of Negative Ion Sources

Download or read book Development and Applications of Negative Ion Sources written by Vadim Dudnikov and published by Springer Nature. This book was released on 2023-06-22 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the development of sources of negative ions and their application in science and industry. It describes the physical foundations and implementation of the key methods of negative ion production and control, such as charge exchange, thermionic emission, plasma volume, secondary emission (sputtering) and surface-plasma sources, as well as the history of their development. Following on from this essential foundational material, the book goes on to explore transport of negative ion beams, and beam-plasma instabilities. Now in its second edition, the book has been substantially expanded and updated to address the many developments since it was first published, most importantly the development and investigation of cesiated surfaces with work function ~1.2-1.3 eV in conditions close to discharges in surface plasma sources. The book also includes a new chapter on development of conversion targets for high-energy neutral beam injectors, covering gas targets, plasma targets and photon targets for efficient conversion of high energy negative ion beams to neutral beams. With exposition accessible at the graduate level, and a comprehensive bibliography, this book will appeal to all students and researchers whose work concerns ion sources and their applications to accelerators, beam physics, storage rings, cyclotrons, and plasma traps.

Book Development and Applications of Negative Ion Sources

Download or read book Development and Applications of Negative Ion Sources written by Vadim Dudnikov and published by Springer Nature. This book was released on 2019-10-18 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the development of sources of negative ions and their application in science and industry. It describes the physical foundations and implementation of the key methods of negative ion production and control, such as charge exchange, thermionic emission, secondary emission (sputtering) and surface-plasma sources, as well as the history of their development. Following on from this essential foundational material, the book goes on to explore transport of negative ion beams, and beam-plasma instabilities. With exposition accessible at the graduate level, and a comprehensive bibliography, this book will appeal to all students and researchers whose work concerns ion sources and their applications to accelerators, beam physics, storage rings, cyclotrons, and plasma traps.

Book Negative Halogen Ions for Fusion Applications

Download or read book Negative Halogen Ions for Fusion Applications written by K. N. Leung and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past quarter century, advances in hydrogen negative ion sources have extended the usable range of hydrogen isotope neutral beams to energies suitable for large magnetically confined fusion devices. Recently, drawing upon this experience, negative halogen ions have been proposed as an alternative to positive ions for heavy ion fusion drivers in inertial confinement fusion, because electron accumulation would be prevented in negative ion beams, and if desired, the beams could be photo-detached to neutrals. This paper reports the results of an experiment comparing the current density and beam emittance of Cl+ and Cl- extracted from substantially ion-ion plasmas with that of Ar+ extracted from an ordinary electron-ion plasma, all using the same source, extractor, and emittance scanner. At similar discharge conditions, the Cl- current was typically 85 - 90% of the positive chlorine current, with an e-/ Cl- ratio as low as seven without grid magnets. The Cl- was as much as 76% of the Ar+ current from a discharge with the same RF drive. The minimum normalized beam emittance and inferred ion temperatures of Cl+, Cl-, and Ar+ were all similar, so the current density and optical quality of Cl- appear as suitable for heavy ion fusion driver applications as a positive noble gas ion of similar mass. Since F, I, and Br should all behave similarly in an ion source, they should also be suitable as driver beams.

Book A Study of Negative Ion Sources for a Charge exchange Accelerator

Download or read book A Study of Negative Ion Sources for a Charge exchange Accelerator written by Toivo Henry Koski and published by . This book was released on 1956 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Production and Neutralization of Negative Ions and Beams

Download or read book Production and Neutralization of Negative Ions and Beams written by Martin P. Stockli and published by American Institute of Physics. This book was released on 2007-08-30 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reported advances with small sources of negative ions, especially negative hydrogen ions, drive the progress of many accelerators and enable new research methods and technologies. Large sources of negative deuterium ions are being developed for the international experimental fusion reactor (ITER) that will require 40 MW of plasma heating. The developments increasingly use computer modeling to understand the underlying physics, improve existing, and develop new technologies.

Book High Current Ion Source Development for Heavy Ion Fusion

Download or read book High Current Ion Source Development for Heavy Ion Fusion written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We are developing high-current-density high-brightness sources for Heavy Ion Fusion applications. Heavy ion driven inertial fusion requires beams of high brightness in order to achieve high power density at the target for high target gain. At present, there are no existing ion source types that can readily meet all the driver HIF requirements, though sources exist which are adequate for present experiments and which with further development may achieve driver requirements. Our two major efforts have been on alumino-silicate sources and RF plasma sources. Experiments being performed on a 10-cm alumino-silicate source are described. To obtain a compact system for a HIF driver we are studying RF plasma sources where low current beamlets are combined to produce a high current beam. A 80-kV 20-[micro]s source has produced up to 5 mA of Ar[sup+] in a single beamlet. The extraction current density was 100 mA/cm[sup 2]. We present measurements of the extracted current density as a function of RF power and gas pressure, current density uniformity, emittance, and energy dispersion (due to charge exchange).

Book High Current Ion Source Development for Heavy Ion Fusion

Download or read book High Current Ion Source Development for Heavy Ion Fusion written by J. W. Kwan and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We are developing high-current-density high-brightness sources for Heavy Ion Fusion applications. Heavy ion driven inertial fusion requires beams of high brightness in order to achieve high power density at the target for high target gain. At present, there are no existing ion source types that can readily meet all the driver HIF requirements, though sources exist which are adequate for present experiments and which with further development may achieve driver requirements. Our two major efforts have been on alumino-silicate sources and RF plasma sources. Experiments being performed on a 10-cm alumino-silicate source are described. To obtain a compact system for a HIF driver we are studying RF plasma sources where low current beamlets are combined to produce a high current beam. A 80-kV 20-{micro}s source has produced up to 5 mA of Ar{sup +} in a single beamlet. The extraction current density was 100 mA/cm{sup 2}. We present measurements of the extracted current density as a function of RF power and gas pressure, current density uniformity, emittance, and energy dispersion (due to charge exchange).

Book Analysis and Interpretation of a High Density Tandem Negative Ion Source

Download or read book Analysis and Interpretation of a High Density Tandem Negative Ion Source written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last few years the development of tandem-discharge hydrogen-negative-ion-source systems has proceeded along both experimental and theoretical lines. To some extent these developments have proceeded independently, either the available theoretical model was inadequate to account for a specific geometrical configuration, or the experimental data was not sufficient to provide adequate input parameters for calculation. In the tandem system described here the electron temperature, electron density, and other relevant parameters have been obtained for a high-density system whose electron densities range up to 3 - 5 x 1012 electrons cm−3. The model calculation for the atomic processes has been extended to include both electron density and electron temperature spatial variations through the second chamber. These spatial variations are essential for an adequate interpretation of tandem systems where steep density gradients may occur beyond the magnetic filter region. In this paper we shall combine the experimental density data with the new spatially dependent atomic model for the purpose of attempting a correlation of the observed and calculated current densities. 9 refs., 8 figs., 3 tabs.