Download or read book Time Evolution of Endpoint Energy of Bremsstrahlung Spectra and Ion Production from an Electron Cyclotron Resonance Ion Source written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron cyclotron resonance ion sources (ECRIS) are used to produce high charge state heavy ion beams for the use of nuclear and materials science, for instance. The most powerful ECR ion sources today are superconducting. One of the problems with superconducting ECR ion sources is the use of high radio frequency (RF) power which results in bremsstrahlung radiation adding an extra heat load to the cryostat. In order to understand the electron heating process and timescales in the ECR plasma, time evolution measurement of ECR bremsstrahlung was carried out. In the measurements JYFL 14 GHz ECRIS was operated in a pulsed mode and bremsstrahlung data from several hundred RF pulses was recorded. Time evolution of ion production was also studied and compared to one of the electron heating theories. To analyze the measurement data at C++ program was developed. Endpoint energies of the bremsstrahlung spectra as a function of axial magnetic field strength, pressure and RF power are presented and ion production timescales obtained from the measurements are compared to bremsstrahlung emission timescales and one of the stochastic heating theories.
Download or read book Electron Cyclotron Resonance Ion Sources and ECR Plasmas written by R Geller and published by Routledge. This book was released on 2018-12-13 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acknowledged as the "founding father" of and world renowned expert on electron cyclotron resonance sources Richard Geller has produced a unique book devoted to the physics and technicalities of electron cyclotron resonance sources. Electron Cyclotron Resonance Ion Sources and ECR Plasmas provides a primer on electron cyclotron phenomena in ion sour
Download or read book Perturbative Measurements of Electron Cyclotron Resonance Ion Source Plasmas written by Derek Elwin Neben and published by . This book was released on 2019 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heavy ion accelerators are a valuable resource for the nuclear science community to study atomic physics. One such heavy ion accelerator is the Coupled Cyclotron Facility (CCF) at the National Superconducting Cyclotron Laboratory (NSCL) which relies on Electron Cyclotron Resonance (ECR) ion sources to provide the primary beam to the target. ECR ion sources are essential for the efficient operation of research accelerators such as the CCF, providing high currents of highly charged ions. Highly charged ion beams increase the efficiency of the accelerators, but require longer confinement times and higher temperature plasmas in the ion sources than is necessary to produce singly charged beams. The need to use high temperature and low density plasmas creates challenges including those relating to plasma stability. ECR ion sources provide a good platform to accept metallic vapor ovens and sputtering probes allowing the CCF to accelerate up to 30 types of beams ranging from oxygen to uranium. Furthermore, ECR ion sources use no filaments or cathodes providing a high degree of reliability for the accelerator facility. As the intensity frontier demands ever rarer isotopes from accelerator facilities, the heavy ion beam intensity must increase [70], which creates new demands from the ion sources.The work presented within this dissertation set out to better understand the mechanism that confines highly charged ions in the ECR plasma. Specifically, it was explored if hot electrons (energy larger than 50 keV) contribute to ion confinement by generating an electrostatic well in the plasma potential [68]. Perturbative measurements of ECR ion sources are presented with the aim to explore ion confinement times: pulsed sputtering (Chapter 4) and amplitude modulation (Chapter 5). Chapter 3 explores the geometry of the sputtering probe with respect to the magnetic field which was crucial to produce reliable pulsed sputtering results on the ECR ion source. Axial pulsed sputtering, which could be conveniently implemented on fully superconducting sources, incorporated a bias disc effect that highly perturbed the plasma. Radial sputtering was emulated by placing a semi-shielded probe along the plasma chamber wall in between the electron loss surfaces.Ion confinement time was characterized through the decay time of the beam current, which is proportional to ion confinement time. Ion beam decay times were measured for different charge states of gold in an oxygen plasma in Chapter 4. Decay time always increased with increasing charge state. Decay time also increased with hot electron temperature for lower frequency operation (13 GHz), but reached an optimized value for higher frequency operation (18 GHz) due to plasma instabilities. Electrostatic confinement of ions appeared to be the most plausible mechanism to explain the observed decay time behaviors. A novel perturbative measurement technique was developed for ECR ion sources using Amplitude Modulation (AM) of microwave power. The AM measurement was originally motivated by whether or not 50~kHz modulation in microwave power (from the microwave source) would be observable in the beam current. A systematic study was organized on the University of Jyvaskyla Physics Department (JYFL) normal conducting ECR ion source in Jyvaskyla Finland. Chapter 5 presents the beam current response to AM on the 14 GHz ECR ion source for different weights of noble gases, magnetic fields, and vacuum pressures. The beam current amplitude generally decayed exponentially for frequencies higher than around 400 Hz with the modulation highly suppressed at 10 kHz.
Download or read book SWISSCASE written by Michael Bodendorfer and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2009 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ions are atoms that have lost or gained one or more electrons, providing the ions with a negative or a positive charge. Unlike bound ions found in solutions, free ions are very rare on Earth but are abundantly found in interplanetary space and cometary atmospheres. Ground based ion sources, which produce free ions to simulate these science targets, are used to calibrate space flight instruments on Earth prior to flight. In order to provide a brighter and more versatile ion source to calibrate future space instrumentation at the University of Bern, Switzerland, this thesis presents planing, realization and characterization of a new high performance ion source. SWISSCASE, the Solar Wind Ion Source Simulator for the CAlibration of Space Experiments, is optimized for production of highly charged ions such as 2 A of Ar8+ and 80 pA of Ar12+. The ions are produced by an electron cyclotron resonance plasma which is heated by microwaves with a frequency of 10 GHz. The plasma is confined by a very compact full permanent magnet hexapole which makes the ion source highly attractive for the operation on a high voltage terminal due to its intrinsically low power consumption.
Download or read book Limits of Applicability of the Theory of Bremsstrahlung Electrons and Pair Production for High Energies written by L. Landau and published by . This book was released on 1953 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ion Cyclotron Resonance Spectrometry II written by H. Hartmann and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Properties of Electron Cyclotron Resonance Plasma Sources written by Aseem Kumar Srivastava and published by . This book was released on 1995 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Cyclotron Emission And Electron Cyclotron Resonance Heating Ec 15 Proceedings Of The 15th Joint Workshop With Cd rom written by John Lohr and published by World Scientific. This book was released on 2009-04-15 with total page 583 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Download or read book Characterization of Electron Cyclotron Resonance Ion Source Instabilities by Charged Particle Diagnostics written by Bryan Isherwood and published by . This book was released on 2020 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ion sources are invaluable tools for producing charge particles for scientific, industrial, and medical applications. In particular, Electron Cyclotron Resonance (ECR) ion sources (ECRIS) are high power sources capable of producing high intensity, high charge state beams of heavy ions. The system uses microwaves to resonantly heat of electrons within an inhomogeneous magnetic trap. However, the internal dynamics of the resulting plasma are complex and poorly understood. In particular, the excitation of kinetic instabilities within the plasma can make operating these ion sources difficult and unpredictable. This thesis focuses on studying these instabilities to determine ways to optimize ECRIS performance by minimizing their impact on the extracted beam current.This study focuses on two measurements that look at the steady-state and time-resolved measurements of charged particle currents escaping the ion source during stable and unstable operations. The first measurement is a novel diagnostic of electrons escaping confinement from the plasma chamber. The second was a measurement of high charge state ions (Ar8+) extracted from the plasma chamber over a broad set of parameter spaces. These measurements provide insight into the ideal operating conditions for an ECR ion source and the dynamics of the ion and electron populations within its plasma.
Download or read book Status of ECR Electron Cyclotron Resonance Source Technology written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 charge states at useful intensities for nuclear physics experiments. Since the maximum energy set by the bending limit of a cyclotron scales with the square of the charge state, the installation of ECR sources on cyclotrons has provided an economical path to raise the energy. Another characteristic of ECR sources is that the discharge is produced without cathodes, so that only the source material injected into an ECR source is consumed. As a result, ECR sources can be operated continuously for periods of weeks without interruption. Techniques have been developed in the last few years, which allow these sources to produce beams from solid materials. The beam emittance from ECR sources is in the range of 50 to 200 .pi. mm-mrad at 10 kV. The principles of ECR ion sources are discussed, and present and future ECR sources are reviewed.
Download or read book Electron Cyclotron Resonance Ion Sources written by Matthaeus Leitner and published by American Institute of Physics. This book was released on 2005-03-23 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Berkeley, California, 26-30 September 2004
Download or read book Proceedings of the Fifteenth Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating written by John Lohr and published by World Scientific. This book was released on 2009 with total page 583 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Download or read book Design and Testing of an Electron Cyclotron Resonance Heating Ion Source for Use in High Field Compact Superconducting Cyclotrons written by Mark E. Artz and published by . This book was released on 2012 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main goal of this project is to evaluate the feasibility of axial injection of a high brightness beam from an Electron Cyclotron Resonance ion source into a high magnetic field cyclotron. Axial injection from an ion source with high brightness is important to reduce particle losses in the first several turns of acceleration within the cyclotron. Beam brightness is a measure of the beam current and rate of spread of the beam. The ultimate goal in developing an ECR ion source is to enable reduced beam losses along the entire acceleration path from the ion source through the cyclotron, allowing for a high beam current accelerator. Cyclotrons with high beam current have the potential to improve the availability of proton radiation therapy. Proton radiation therapy is a precisely targeted treatment capable of providing an excellent non-invasive treatment option for tumors located deep within tissue. In order to model injection into high field it is necessary to measure the parameters of the beam extracted from the ion source. The two most important beam parameters are emittance and beam current. The emittance of the beam is a measurement of the rate of beam spread along the path of the beam and beam current is a measurement of the energy and quantity of particles within a charged particle beam. This thesis presents the design and analysis of an ECR Ion Source and the instruments used to measure the emittance and beam current. Based on the modeling of the ECR ion source beam and the data gathered during testing, the ECR ion source presented in this thesis has the potential to provide a high brightness beam capable of high field axial injection. Beam simulations provide insight into the performance of the ECR ion source in high magnetic field. Axial beam injection from an external ion source is promising with moderate refinements to the ECR ion source.
Download or read book Experimental Study of an Ion Cyclotron Resonance Accelerator written by Christopher T. Ramsell and published by . This book was released on 2000 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Cyclotron Emission And Electron Cyclotron Resonance Heating Ec 16 Proceedings Of The 16th Joint Workshop With Cd rom written by Ronald Prater and published by World Scientific. This book was released on 2011-02-21 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings volume, the sixteenth in a biannual series, presents a snapshot of the state of current research worldwide on Electron Cyclotron Emission (ECE) and Electron Cyclotron Resonance Heating (ECRH) and related technologies. The papers address the physics, both theory and experiment, of ECE and ECRH. The technologies of high power millimeter-wave sources — gyrotrons — and transmission lines and launchers are included. The focus is on physics and technology relevant to the research and development of nuclear fusion.
Download or read book Physics of Multiply Charged Ions and Physics of Electron Cyclotron Resonance Ion Sources written by S. L. Bilman and published by . This book was released on 1988 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Cyclotron Resonance ECR Ion Sources written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Starting with the pioneering work of R. Geller and his group in Grenoble (France), at least 14 ECR sources have been built and tested during the last five years. Most of those sources have been extremely successful, providing intense, stable and reliable beams of highly charged ions for cyclotron injection or atomic physics research. However, some of the operational features of those sources disagreed with commonly accepted theories on ECR source operation. To explain the observed behavior of actual sources, it was found necessary to refine some of the crude ideas we had about ECR sources. Some of those new propositions are explained, and used to make some extrapolations on the possible future developments in ECR sources.
