Download or read book Conventional and Superconducting Rf Linac Designs for the APT Project written by and published by . This book was released on 1996 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proton linac for APT (Accelerator Production of Tritium) will produce a nominal CW beam power of 130 MW at 1300 MeV. Two designs are currently under consideration. Reference design is composed entirely of normal-conducting (NC) copper accelerating structures, while an advanced-technology design employs superconducting Nb cavities above 217 MeV. Front-end accelerator for both concepts is a 100-mA NC linac. In this paper, the two APT linac designs are described and compared in terms of key factors, including power efficiency, beam loss control, machine availability and flexibility, and construction and operating costs.
Download or read book Status of Superconducting RF Linac Development for APT written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes the development progress of high-current superconducting RF linacs in Los Alamos, performed to support a design of the linac for the APT (Accelerator Production of Tritium) Project. The APT linac design includes a CW superconducting RF high-energy section, spanning an energy range of 211-1030 MeV, and operating at a frequency of 700 MHz with two constant-beta sections (beta=0.64 and beta=0.82). In the last two years, we have progressed toward building a cryomodule with beta=0.64. We completed the designs of the 5-cell superconducting cavities and the 210-kW power couplers, and are currently testing the cavities and the couplers. We are scheduled to begin assembly of the cryomodule in September 2000. In this paper, we present an overview of the status of our development efforts and a report on the results of the cavity and coupler testing program.
Download or read book RF Linear Accelerators written by Thomas P. Wangler and published by John Wiley & Sons. This book was released on 2008-11-21 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Borne out of twentieth-century science and technology, the field of RF (radio frequency) linear accelerators has made significant contributions to basic research, energy, medicine, and national defense. As we advance into the twenty-first century, the linac field has been undergoing rapid development as the demand for its many applications, emphasizing high-energy, high-intensity, and high-brightness output beams, continues to grow. RF Linear Accelerators is a textbook that is based on a US Particle Accelerator School graduate-level course that fills the need for a single introductory source on linear accelerators. The text provides the scientific principles and up-to-date technological aspects for both electron and ion linacs. This second edition has been completely revised and expanded to include examples of modern RF linacs, special linacs and special techniques as well as superconducting linacs. In addition, problem sets at the end of each chapter supplement the material covered. The book serves as a must-have reference for professionals interested in beam physics and accelerator technology.
Download or read book Physics And Technology Of Linear Accelerator Systems Proceedings Of The 2002 Joint Uspas cas japan russia Accelerator School written by Helmut Wiedemann and published by World Scientific. This book was released on 2004-03-15 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is useful to people working or planning to work in the field of linear accelerators. It is a good reference, presenting the most recent advances in the field. The intended audience are researchers, practitioners, academics and graduate students.The proceedings have been selected for coverage in:• Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)• CC Proceedings — Engineering & Physical Sciences
Download or read book Physics Design of APT Linac with Normal Conducting Rf Cavities written by and published by . This book was released on 1996 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The accelerator based production of tritium calls for a high-power, cw proton linac. Previous designs for such a linac use a radiofrequency quadrupole (RFQ), followed by a drift-tube linac (DTL) to an intermediate energy and a coupled-cavity linc (CCL) to the final energy. The Los Alamos design uses a high-energy (6.7 MeV) RFQ followed by the newly developed coupled-cavity drift-tube linac (CCDTL) and a CCL. This design accommodates external electromagnetic quadrupole lenses which provide a strong uniform focusing lattice from the end of the RFQ to the end of the CCL. The cell lengths in linacs of traditional design are typically graded as a function of particle velocity. By making groups of cells symmetric in both the CCDTL and CCL, the cavity design as well as mechanical design and fabrication is simplified without compromising the performance. At higher energies, there are some advantages of using superconducting rf cavities. Currently, such schemes are under vigorous study. This paper describes the linac design based on normal conducting cavities and presents simulation results.
Download or read book The Savannah River Accelerator Project And Complementary Spallation Neutron Sources written by Frank T Avignone Iii and published by World Scientific. This book was released on 1998-02-24 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings volume is a collection of papers dealing with the applications of spallation neutron sources to pure science, applied science and defense programs. The topics, ranging from accelerator technology to applications in materials science and neutrino physics, are covered by experts in their respective fields.
Download or read book CERN written by and published by . This book was released on 1996 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Progress of APT Superconducting Linac Engineering Development written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors initiated a program to develop superconducting (SC) RF for high-power proton linacs. These linacs are useful in accelerator-driven transmutation technologies and the Accelerator Production of Tritium (APT) Project. They are developing multicell niobium cavities with elliptical-cell shapes at 700 MHz. These cavities, unlike most elliptical cavities for electron accelerators, are designed to accelerate protons at [beta]
Download or read book Distributed coupling Linear Particle Accelerators written by Mamdouh Hassan Nasr and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Linear particle accelerators (linacs) are essential for future discovery machines as well as many advanced medical and industrial applications. A linac is formed from a set of cascaded RF cavities (cells). For a typical electron linac, such as the SLAC linear accelerator, RF power is fed to the linac from one point and flows to adjacent cells through the beam tunnel. Consequently, the linac design process requires careful consideration of the coupling between adjacent cells. This limits the ability of the designer to optimize the cell shape for high RF-to-beam efficiency and/or craft the field on the surface for high-gradient operation. We introduce a novel particle accelerator technology that utilizes a periodic feeding network to feed every accelerating cell independently. This eliminates the need for the coupling between cells, giving considerable optimization flexibility for the shape of the accelerator cells. This dissertation discusses the concept behind this topology and presents how such a concept is developed and implemented through a set of key research milestones. The theory of the distributed-coupling linac is presented alongside the associated optimization techniques that take full benefit of the resultant design flexibility. Compared to a conventional linac, our designed and tested structures provide approximately double the shunt impedance. A novel manufacturing technique is enabled by observing that both the cells and the feeding network have planes with no currents passing through them. This allowed the manufacturing of the structure from two blocks. From an economical point of view, this reduces the part count by about two orders of magnitude in comparison to traditional ways of building the structures from half-cell cups. Additionally, this method allows us to assemble the structure without the necessary brazing steps typically needed for traditional linacs. Hence, the copper or doped-copper material hardness properties can be maintained, further enhancing the ability of the surface to resist damage due to cyclic fatigue. Cryogenic operation of normal-conducting linacs substantially reduces their surface resistance and hence improves RF-to-beam efficiency. The reduced losses also reduce the transient temperature rise on the surface, which is the root cause of the surface cyclic fatigue that leads to surface distortions and consequently breakdown events. That cyclic fatigue is further reduced because the copper yield strength is increased at lower temperatures. In this work, we present the first demonstration of high-gradient acceleration of an electron-beam at a cryogenic temperature of 77 K. Experimental operation of the distributed-coupling structure at 77 K resulted in a reduction in the breakdown rates by two orders of magnitude. Furthermore, the concept of distributed-coupling is extended to superconducting accelerators. Compared to conventional designs, the provided optimization flexibility of the distributed-coupling topology leads to optimized geometries with a reduced surface magnetic field and RF power loss. This reduction should allow for high-gradient operation and reduced system cost. We present our initial attempts to build and test a superconducting distributed-coupling linac. Finally, the concept of distributed-coupling is extended to utilize two accelerating modes that operate simultaneously in the same linac. Dual-mode acceleration enhances the shunt impedance while allowing the structure to operate at much higher gradients. The latter advantage is due to the fact that a given point on the cavity surface does not experience the sum of the peak fields from the two modes at the same time. An extra degree of freedom is obtained by not requiring the operating frequencies to be harmonically related; it is sufficient to have a common sub-harmonic. The value of this sub-harmonic determines the distance between the bunches that can be accelerated. The proposed dual-mode architecture prevents the leakage of the high-frequency mode through the coupling ports of the low-frequency mode by introducing a choke feature in the low-frequency port. Moreover, this architecture preserves the structure symmetry and allows for manufacturing the structure from quadrant copper blocks.
Download or read book Results of the APT RF Power Coupler Development for Superconducting Linacs written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the new baseline APT (Accelerator Production of Tritium) linac design, the power couplers are required to transmit 420 kW of CW RF power to the superconducting cavities at 700 MHz. These couplers consist of an airside waveguide-to-coax transition, an air/vacuum break made by two planar, coaxial windows, and a vacuum-side coaxial antenna section. The coaxial antenna allows adjustability of the RF matching to the superconducting cavities. Design, fabrication, and testing of the power coupler/window occurred over the last four years, and room temperature testing of the prototype design is complete. Coupler/window assemblies have transmitted power to 1 MW, CW and have handled full reflected 850 kW, CW over a limited standing-wave phase range. Couplers were tested with a portion of the outer conductor cooled by liquid nitrogen to study the effects of condensed gases. No hard multipacting barriers were encountered during any of this room temperature testing. Final results, conclusions, and lessons learned about the coupler design, fabrication, and testing will be discussed.
Download or read book Assessment of Alternative RF Linac Structures for APT written by and published by . This book was released on 1997 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The APT program has been examining both normal and superconducting variants of the APT linac for the past two years. A decision on which of the two will be the selected technology will depend upon several considerations including the results of ongoing feasibility experiments, the performance and overall attractiveness of each of the design concepts, and an assessment of the system-level features of both alternatives. The primary objective of the Assessment of Alternative RF Linac Structures for APT study reported herein was to assess and compare, at the system-level, the performance, capital and life cycle costs, reliability/availability/maintainability (RAM) and manufacturing schedules of APT RF linear accelerators based upon both superconducting and normal conducting technologies. A secondary objective was to perform trade studies to explore opportunities for system optimization, technology substitution and alternative growth pathways and to identify sensitivities to design uncertainties.
Download or read book APT Accelerator Technology written by and published by . This book was released on 1996 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proposed accelerator production of tritium (APT) project requires an accelerator providing a cw proton beam of 100 mA at 1300 MeV. Since most of the technical risk of a high-current cw (continuous-wave, 100% DF) accelerator resides in the low-energy section, Los Alamos is building a 20 MeV duplicate of the accelerator front end to confirm design codes, beam performance, and demonstrate operaional reliability. We report on design details of this low-energy demonstration accelerator (LEDA) and discuss the integrated design of the full accelerator for the APT plant. LEDA's proton injector is under test and has produced more than 130 mA at 75 keV. Fabrication is proceeding on a 6.7-KeV, 8-m long RFQ, and detailed design is underway on coupled-cavity drift-tube linac (CCDTL) structures. Detailed design and technology experiments are underway on medium-beta superconducting cavities to assess feasibility of replacing the conventional (room-temperature copper) high-energy linac with a linac made of niobium superconducting RF cavities.
Download or read book Proceedings of the XVIII International Linear Accelerator Conference written by and published by . This book was released on 1996 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conceptual Design of the SPL a High power Superconducting H Linac at CERN written by M. Vretenar and published by . This book was released on 2000 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2092 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wake Field Effect Analysis in APT Linac written by and published by . This book was released on 1998 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1.7-GeV 100-mA CW proton linac is now under design for the Accelerator Production of Tritium (APT) Project. The APT linac comprises both the normal conducting (below 211 MeV) and superconducting (SC) sections. The high current leads to stringent restrictions on allowable beam losses (
Download or read book Simulated Performance of the Superconducting Section of the APT Linac Under Various Fault and Error Conditions written by and published by . This book was released on 1997 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current design for the production of tritium uses both normal-conducting (NC) and superconducting (SC) structures. To evaluate the performance of the superconducting part of the linac which constitutes more than 80% of the accelerator, studies have been made to include the effects of various error and fault conditions. Here, the authors present the simulation results of studies such as effects of rf phase and amplitude errors, cavity/klystron failure, quadrupole misalignment errors, quadrupole gradient error, and beam-input mismatches.
