Download or read book Electron Beam Dynamics in the Long pulse High current DARHT II Linear Induction Accelerator written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Beam Dynamics in the DARHT II Linear Induction Accelerator written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The DARHT-II linear induction accelerator (LIA) accelerates a 2-kA electron beam to more than 17 MeV. The beam pulse has a greater than 1.5-microsecond flattop region over which the electron kinetic energy is constant to within 1%. The beam dynamics are diagnosed with 21 beam-position monitors located throughout the injector, accelerator, and after the accelerator exit, where we also have beam imaging diagnostics. We discuss the tuning of the injector and accelerator, and present data for the resulting beam dynamics. We discuss the tuning procedures and other methods used to minimize beam motion, which is undesirable for its application as a bremsstrahlung source for multi-pulse radiography of exlosively driven hydrodynamic experiments. We also present beam stability measurements, which we relate to previous stability experiments at lower current and energy.
Download or read book Beam Dynamics in a Long pulse Linear Induction Accelerator written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The second axis of the Dual Axis Radiography of Hydrodynamic Testing (DARHT) facility produces up to four radiographs within an interval of 1.6 microseconds. It accomplishes this by slicing four micro-pulses out of a long 1.8-kA, 16.5-MeV electron beam pulse and focusing them onto a bremsstrahlung converter target. The long beam pulse is created by a dispenser cathode diode and accelerated by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for radiography. High frequency motion, such as from beam breakup instability, would blur the individual spots. Low frequency motion, such as produced by pulsed power variation, would produce spot to spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it.
Download or read book Induction Accelerators written by Ken Takayama and published by Springer Science & Business Media. This book was released on 2010-10-05 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: A broad class of accelerators rests on the induction principle whereby the accelerating electrical fields are generated by time-varying magnetic fluxes. Particularly suitable for the transport of bright and high-intensity beams of electrons, protons or heavy ions in any geometry (linear or circular) the research and development of induction accelerators is a thriving subfield of accelerator physics. This text is the first comprehensive account of both the fundamentals and the state of the art about the modern conceptual design and implementation of such devices. Accordingly, the first part of the book is devoted to the essential features of and key technologies used for induction accelerators at a level suitable for postgraduate students and newcomers to the field. Subsequent chapters deal with more specialized and advanced topics.
Download or read book Reviews Of Accelerator Science And Technology Volume 6 Accelerators For High Intensity Beams written by Alexander Wu Chao and published by World Scientific. This book was released on 2014-04-01 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: As particle accelerators strive forever increasing performance, high intensity particle beams become one of the critical demands requested across the board by a majority of accelerator users (proton, electron and ion) and for most applications. Much effort has been made by our community to pursue high intensity accelerator performance on a number of fronts. Recognizing its importance, we devote this volume to Accelerators for High Intensity Beams. High intensity accelerators have become a frontier and a network for innovation. They are responsible for many scientific discoveries and technological breakthroughs that have changed our way of life, often taken for granted. A wide range of topics is covered in the fourteen articles in this volume.
Download or read book A High current Linear induction Accelerator written by N. P. Shepelev and published by . This book was released on 1968 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method of generating powerful electron beams and the use of these beams to generate large amplitude electrostatic waves and to heat a plasma are described. The linear betatron constructed for this study consists of an electron source and an accelerating section formed by a power transformer with unity transformation coefficient. The outline of the design is given in a block diagram and its operation is discussed. An electric field of 6 kv/cm was achieved in the accelerating section. The total potential of 200 kv resulted in electron beam currents of 1000 A. The analysis of the design has shown that the most suitable source of energy is a series of capacitors with spark-gap switching. This scheme eliminates synchronization problems and provides a desirable current pulse. The design reported can bascially serve as a guide in the construction of a high current accelerator operating in the megavolt range. (Author).
Download or read book Electron beam Dynamics for an Advanced Flash radiography Accelerator written by and published by . This book was released on 2015 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beam dynamics issues were assessed for a new linear induction electron accelerator. Special attention was paid to equilibrium beam transport, possible emittance growth, and beam stability. Especially problematic would be high-frequency beam instabilities that could blur individual radiographic source spots, low-frequency beam motion that could cause pulse-to-pulse spot displacement, and emittance growth that could enlarge the source spots. Beam physics issues were examined through theoretical analysis and computer simulations, including particle-in cell (PIC) codes. Beam instabilities investigated included beam breakup (BBU), image displacement, diocotron, parametric envelope, ion hose, and the resistive wall instability. Beam corkscrew motion and emittance growth from beam mismatch were also studied. It was concluded that a beam with radiographic quality equivalent to the present accelerators at Los Alamos will result if the same engineering standards and construction details are upheld.
Download or read book Induction Accelerators and Free electron Lasers at LLNL written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Linear induction accelerators have been developed to produce pulses of charged particles at voltages exceeding the capabilities of single-stage, diode-type accelerators and at currents too high rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multistage induction machine. The advent of magnetic pulse power systems makes sustained operation at high repetition rates practical, and high-average-power capability is very likely to open up many new applications of induction machines. In Part A of this paper, we survey the US induction linac technology, emphasizing electron machines. We also give a simplified description of how induction machines couple energy to the electron beam to illustrate many general issues that designers of high-brightness and high-average-power induction linacs must consider. We give an example of the application of induction accelerator technology to the relativistic klystron, a power source for high-gradient accelerators. In Part B we address the application of LIAs to free-electron lasers. The multikiloampere peak currents available from linear induction accelerators make high-gain, free-electron laser amplifier configurations feasible. High extraction efficiencies in a single mass of the electron beam are possible if the wiggler parameters are appropriately ''tapered'', as recently demonstrated at millimeter wavelengths on the 4-MeV ELF facility. Key issues involved in extending the technology to shorter wavelengths and higher average powers are described. Current FEL experiments at LLNL are discussed. 5 refs., 16 figs.
Download or read book Retuning the DARHT Axis II Linear Induction Accelerator written by and published by . This book was released on 2015 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility uses bremsstrahlung radiation source spots produced by the focused electron beams from two linear induction accelerators (LIAs) to radiograph large hydrodynamic experiments driven by high explosives. The Axis-II 1.7-kA, 1600-ns beam pulse is transported through the LIA by the magnetic field from 91 solenoids as it is accelerated to ~16.5 MeV. The magnetic field produced by the solenoids and 80 steering dipole pairs for a given set of magnet currents is known as the "tune" of the accelerator [1]. From June, 2013 through September, 2014 a single tune was used. This tune was based on measurements of LIA element positions made over several years [2], and models of solenoidal fields derived from actual field measurements [3] [4]. Based on the focus scan technique, changing the tune of the accelerator and downstream transport had no effect on the beam emittance, to within the uncertainties of the measurement. Beam sizes appear to have been overestimated in all prior measurements because of the low magnification of the imaging system. This has resulted in overestimates of emittance by ~50%. The high magnification imaging should be repeated with the old tune for direct comparison with the new tune. High magnification imaging with the new accelerator tune should be repeated after retuning the downstream to produce a much more symmetric beam to reduce the uncertainty of this measurement. Thus, these results should be considered preliminary until we can effect a new tune to produce symmetric spots at our imaging station, for high magnification images.
Download or read book Proceedings of the 1999 Particle Accelerator Conference written by and published by . This book was released on 1999 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Linear Induction Accelerator Parameter Options written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The principal undertaking of the Beam Research Program over the past decade has been the investigation of propagating intense self-focused beams. Recently, the major activity of the program has shifted toward the investigation of converting high quality electron beams directly to laser radiation. During the early years of the program, accelerator development was directed toward the generation of very high current (>10 kA), high energy beams (>50 MeV). In its new mission, the program has shifted the emphasis toward the production of lower current beams (>3 kA) with high brightness (>106 A/(rad-cm)2) at very high average power levels. In efforts to produce these intense beams, the state of the art of linear induction accelerators (LIA) has been advanced to the point of satisfying not only the current requirements but also future national needs.
Download or read book Beam Dynamics in the ETA and ATA 10 KA Linear Induction Accelerators written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The 10 kA ETA and ATA linear induction accelerators are described. Beam instability is the major concern in these high current machines, and the current status of theoretical understanding, and experimental investigations with the 8 cavity ETA, are reviewed. Modifications to the induction cavities are described that have essentially eliminated the transverse resonant modes seen in the ETA.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1994-11 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Beam Converter Target Interactions in Radiographic Accelerators written by F. Chambers and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Linear induction accelerators used in X-ray radiography have single-pulse parameters of the order 20 MeV of electron beam energy, 2 kA of beam current, pulse lengths of 50-100 ns, and spot sizes of 1-2 mm. The thermal energy deposited in a bremsstrahlung converter target made of tantalum from such a pulse is {approx}80 kJ/cc, more than enough to bring the target material to a partially ionized state. The tail end of a single beam pulse, or any subsequent pulse in a multi-pulse train, undergoes a number of interactions with the target that can affect beam transport and radiographic performance. Positive ions extracted from the target plasma by the electron beam space charge can affect the beam focus and centroid stability. As the target expands on the inter-pulse time scale, the integrated line density of material decreases, eventually affecting the X-ray output of the system. If the target plume becomes sufficiently large, beam transport through it is affected by macroscopic charge and current neutralization effects and microscopic beam/plasma instability mechanisms. We will present a survey of some of these interactions, as well as some results of an extensive experimental and theoretical campaign to understand the practical amelioration of these effects, carried out at the ETA-II accelerator facility at the Lawrence Livermore National Laboratory.
Download or read book Proceedings of the 1997 Particle Accelerator Conference written by and published by . This book was released on 1998 with total page 1322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tuning the DARHT Long Pulse Linear Induction Accelerator written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the XVIII International Linear Accelerator Conference written by C. Hill and published by . This book was released on 1996 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:
