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Medical heavy ion accelerator proposals

Description: For several decades, accelerators designed primarily for research in nuclear and high energy physics have been adapted for biomedical research including radiotherapeutic treatment of human diseases such as pituitary disorders, cancer, and more recently, arteriovascular malformations. The particles used in these treatments include pions, protons and heavier ions such as carbon, neon, silicon and argon. Maximum beam energies must be available to penetrate into an equivalent of about 30 cm of water, requiring treatment beams of 250 to 1000 MeV/nucleon. Certain special treatments of superficial melanoma, however, require that beam energies as low as 70 MeV/nucleon also be available. Intensities must be adequate to complete a 100 rad treatment fraction in about 1 minute. For most heavy ion treatments, this corresponds to 10/sup 7/-10/sup 9/ ions/second at the patient. Because this research is best conducted in a dedicated, hospital-based facility, and because of the clinical need for ultra-high reliability, the construction of new and dedicated facilities has been proposed. Heavy ion accelerators can provide a variety of ions and energies, permitting treatment plans that exploit the properties of the ion best suited to each individual treatment, and that employ radioactive beams (such as /sup 11/C and /sup 19/Ne) to precisely confirm the dose localization. The favored technical approach in these proposals utilizes a conventional, strong-focusing synchrotron capable of fast switching between ions and energies, and servicing multiple treatment rooms. Specialized techniques for shaping the dose to conform to irregularly-shaped target volumes, while simultaneously sparing surrounding, healthy tissue and critical structures, are employed in each treatment room, together with the sophisticated dosimetry necessary for verification, monitoring, and patient safety. 3 refs., 8 figs.
Date: May 1, 1985
Creator: Gough, R.A.
Partner: UNT Libraries Government Documents Department

Present status of the Bevalac and design outline of proposed medical accelerator

Description: The Bevalac currently supports a strong and diverse program of scientific research with beams of relativistic heavy ions in the Biomedical and Nuclear Sciences. These programs utilize ions throughout the Periodic Table that range in energy from a few MeV to 2 GeV/nucleon, including radioactive secondary beams, such as neon-19. This paper first provides a brief overview of the Bevalac, its present operational status and the accelerator improvement program, followed by a rationale for the proposed construction of a hospital-based modern synchrotron dedicated to applications in Biomedicine, including the radiotherapeutic treatment of cancer and other human disorders. An outline of the proposed design for the new machine is given, including discussion of the design philosophy, a review of major accelerator components, and the expected performance and operating characteristics.
Date: March 1, 1986
Creator: Gough, R.A.
Partner: UNT Libraries Government Documents Department

PET computer programs for use with the 88-inch cyclotron

Description: This report describes in detail several offline programs written for the PET computer which provide an efficient data management system to assist with the operation of the 88-Inch Cyclotron. This function includes the capability to predict settings for all cyclotron and beam line parameters for all beams within the present operating domain of the facility. The establishment of a data base for operational records is also described from which various aspects of the operating history can be projected.
Date: June 1, 1981
Creator: Gough, R.A. & Chlosta, L.
Partner: UNT Libraries Government Documents Department

Heavy ion medical accelerator options

Description: This paper briefly explores the accelerator technology available for heavy ion medical accelerators in the mass range of 1 to 40 (protons through argon). Machines that are designed to produce the required intensities of a particular design ion, such as silicon (mass 28), can satisfy the intensity requirements for all lighter ions, and can produce beams with higher mass, such as argon, at somewhat reduced, but still useful intensity levels. They can also provide beams of radioactive ions, such as carbon-11 and neon-19, which are useful in diagnostic imaging and for directly verifiable treatments. These accelerators are all based on proven technology, and can be built at predictable costs. It is the conclusion of several design studies that they can be operated reliably in a hospital-based environment. 8 refs., 22 figs.
Date: January 1, 1985
Creator: Gough, R.A. & Alonso, J.R.
Partner: UNT Libraries Government Documents Department

Nuclear science annual report, July 1, 1977-June 30, 1978. [Lawrence Berkeley Laboratory]

Description: Activities for the period July 1, 1977, through June 30, 1978, are reported in the following areas: experimental research (nuclear structure; nuclear reactions and scattering; relativistic heavy ions - projectile and target fragmentation, central collisions; the Table of Isotopes Project, atomic physics, and magnetic monopoles), theory of nuclear collisions (microscopic, macroscopic, relativistic), and apparatus (accelerator operations and development, nuclear instrumentation). Also included are thesis abstracts, publications lists, and an author index. Individual abstracts were prepared for 33 of the reports in this volume. (RWR)
Date: January 1, 1978
Creator: Schroeder, L.S.; Gough, R.A. & Nurmia, M.J. (eds.)
Partner: UNT Libraries Government Documents Department

Recent developments in high charge state heavy ion beams at the LBL 88-inch Cyclotron

Description: Recent advances in design and operation of the internal PIG sources at the LBL 88-Inch Cyclotron have led to the development of high charge state (0.4 < or approx. = to Q/A < or approx. = to 0.5) heavy ion beams between lithium and neon with energies 20 < or approx. = to E/A < or approx. = to 32 MeV per nucleon, including fully stripped ions up to /sup 16/O/sup 8 +/. Total external intensities of these beams range from 10/sup 12/ particles/s for /sup 6/Li/sup 3 +/ to 0.1 particles/s for /sup 16/O/sup 8 +/. Techniques have been developed for routine tune-out of the low intensity beams. These include use of model beams and reliance on the large systematic data base of cyclotron parameters which has been developed over many years of operation. Techniques for delivery of these weak beams to the experimental target areas are presented. Source design and operation, including special problems associated with Li, Be, and B beams are discussed.
Date: September 13, 1978
Creator: Gough, R.A.; Clark, D.J. & Glasgow, L.R.
Partner: UNT Libraries Government Documents Department

Design of an RFQ-based, H/sup -/ injector for the BNL/FNAL 200 MeV proton linacs

Description: An LBL/BNL/FNAL collaboration has been formed to design an RFQ-based Cockcroft-Walton replacement, suitable for use at the Brookhaven and Fermilab 200 MeV proton linacs. A common design for the ion source and the RFQ will result in an economical construction and testing program compatible with both applications. The technical requirements have been evaluated and it appears that they can be satisfied with identical RFQs, capable of accelerating 50 mA of H/sup -/ from 35 to 750 keV, at a nominal frequency of 200 MHz.
Date: June 1, 1986
Creator: Gough, R.A.; Staples, J.; Tanabe, J.; Yee, D.; Howard, D.; Curtis, C. et al.
Partner: UNT Libraries Government Documents Department

Compact heavy ion RFQ preaccelerator for use at the CERN Linac I

Description: This paper describes the LBL contribution to a project designed to provide fully-stripped oxygen beams for acceleration in the CERN PS complex. A preaccelerator for Linac I, consisting of an ECR ion source, an RFQ linac, and rf matching cavities, is being assembled as part of a collaborative arrangement among LBL, GSI, and CERN. The RFQ, designed and built at LBL, will accept analyzed oxygen +6 beam from the ECR at 5.6 keV/amu, and accelerate it to 139.5 keV/amu, the injection energy required for 2 ..beta..lambda operation of Linac I. Stripping to +8 will be done with a foil stripper at 12.5 MeV/amu at the exit of Linac I. The RFQ operates at 202.56 MHz and is 0.86 meters in length. The structure is stabilized with vane coupling rings, and uses a single drive loop and a single tuning loop. 5 refs., 3 figs.
Date: May 1, 1985
Creator: Gough, R.A.; Staples, J.; Caylor, R.; Howard, D.; MacGill, R. & Tanabe, J.
Partner: UNT Libraries Government Documents Department

High energy beam transport system for a Heavy Ion Medical Accelerator

Description: A beam transport system for a Heavy Ion Medical Accelerator is presented. The design allows for ease of tuning, similarity of tuning between different beam lines, and future expansion of the number of beamlines. An option for generating secondary beams with acceptable transmission losses to all treatment areas is also included in the design, as is a vertical beamline option for use with patients in a horizontal position. 3 refs., 5 figs., 3 tabs.
Date: May 1, 1985
Creator: Renner, T.R.; Chu, W.T.; Gough, R.A.; Staples, J. & Tanabe, J.
Partner: UNT Libraries Government Documents Department

Emittance measurements of high charge state argon beams from a pig source

Description: The emittances of beams of Ar$sup 4+$ to Ar$sup 8+$ were measured in the axial and radial planes. The extraction voltage was 10 kV and the magnetic field was varied from about 0.5 to 0.6 Tesla. The anode slit was varied in distance from the arc, which was run both dc and pulsed. The emittance was nearly independent of charge state, but increased with total beam current. A small bowing of the arc column, which made evaluation of mirror field effects difficult, was discovered. (auth)
Date: October 1, 1975
Creator: Bex, L.; Clark, D.J.; Ellsworth, C.E.; Estrella, R.M.; Gough, R.A. & Holley, W.R.
Partner: UNT Libraries Government Documents Department

Development of ion sources for ion projection lithography

Description: Multicusp ion sources are capable of generating ion beams with low axial energy spread as required by the Ion Projection Lithography (IPL). Longitudinal ion energy spread has been studied in two different types of plasma discharge: the filament discharge ion source characterized by its low axial energy spread, and the RF-driven ion source characterized by its long source lifetime. For He{sup +} ions, longitudinal ion energy spreads of 1-2 eV were measured for a filament discharge multicusp ion source which is within the IPL device requirements. Ion beams with larger axial energy spread were observed in the RF-driven source. A double-chamber ion source has been designed which combines the advantages of low axial energy spread of the filament discharge ion source with the long lifetime of the RF-driven source. The energy spread of the double chamber source is lower than that of the RF-driven source.
Date: May 1, 1996
Creator: Lee, Y.; Gough, R.A.; Kunkel, W.B.; Leung, K.N. & Perkins, L.T.
Partner: UNT Libraries Government Documents Department

The National Spallation Neutron Source Collaboration: Towards a new pulsed neutron source in the United States

Description: The US Department of Energy has commissioned Oak Ridge National Laboratory to initiate the conceptual design for a next-generation pulsed spallation neutron source. Current expectation is for a construction start in FY 1998, with commencement of operations in 2004. For this project, ORNL has entered into a collaborative arrangement with LBNL, BNL, LANL (and most recently ANL). The conceptual design study is now well underway, building on the strong base of the extensive work already performed by various Laboratories, as well as input from the user community (from special BESAC subpanels). Study progress, including accelerator configuration and plans for resolution of critical issues, is reported in this paper.
Date: July 1, 1996
Creator: Appleton, B.R.; Ball, J.B.; Alonso, J.R.; Gough, R.A.; Weng, W.T.; Jason, A. et al.
Partner: UNT Libraries Government Documents Department

Plasma ignition schemes for the SNS radio-frequency driven H- source

Description: The H{sup -} ion source for the Spallation Neutron Source (SNS) is a cesiated, radio-frequency driven (2 MHz) multicusp volume source which operates at a duty cycle of 6% (1 ms pulses and 60 Hz). In pulsed RF driven plasma sources, ignition of the plasma affects the stability of source operation and the antenna lifetime. We are reporting on investigations of different ignition schemes, based on secondary electron generation in the plasma chamber by UV light, a hot filament, a low power RF plasma (cw, 13.56 MHz), as well as source operation solely with the high power (40 kW) 2 MHz RF. We find that the dual frequency, single antenna scheme is most attractive for the operating conditions of the SNS H{sup -} source.
Date: September 6, 2001
Creator: Schenkel, T.; Staples, J.W.; Thomae, W.; Reijonen, J.; Gough, R.A.; Leung, K.N. et al.
Partner: UNT Libraries Government Documents Department

Development of a radioactive ion beam test stand at LBNL

Description: For the on-line production of a {sup 14}O{sup +} ion beam, an integrated target--transfer line ion source system is now under development at LBNL. {sup 14}O is produced in the form of CO in a high temperature carbon target using a 20 MeV {sup 3}He beam from the LBNL 88'' Cyclotron via the reaction {sup 12}C({sup 3}He,n){sup 14}O. The neutral radioactive CO molecules diffuse through an 8 m room temperature stainless steel line from the target chamber into a cusp ion source. The molecules are dissociated, ionized and extracted at energies of 20 to 30 keV and mass separated with a double focusing bending magnet. The different components of the setup are described. The release and transport efficiency for the CO molecules from the target through the transfer line was measured for various target temperatures. The ion beam transport efficiencies and the off-line ion source efficiencies for Ar, O{sub 2} and CO are presented. Ionization efficiencies of 28% for Ar{sup +}, 1% for CO, 0.7% for O{sup +}, 0.33 for C{sup +} have been measured.
Date: October 5, 1998
Creator: Burke, J.; Freedman, S.J.; Fujikawa, B.; Gough, R.A.; Lyneis, C.M.; Vetter, P. et al.
Partner: UNT Libraries Government Documents Department

INITIAL RESULTS WITH THE BERKELEY ON-LINE MASS SEPARATOR - RAMA

Description: We have for some time been interested in developing a reasonably fast and universal (having little or no chemical selectivity) on-line mass analysis system to expand our capabilities in studying nuclei far from stability. The system selected was originally proposed by Nitschke and is termed RAMA an acronym for Recoil Atom Mass Analyzer. Basically, this system utilizes the helium-jet method to transport activity to a Sidenius hollow-cathode ion source which is coupled to a mass spectrometer. A comprehensive discussion of RAMA will appear elsewhere.
Date: November 1, 1977
Creator: Cerny, J.; Moltz, D.M.; Evans, H.C.; Vieira, D.J.; Parry, R.F.; Wouters, J.M. et al.
Partner: UNT Libraries Government Documents Department

The SNS RFQ Commissioning

Description: LBNL has built for the Spallation Neutron Source (SNS) project a 402.5 MHz RFQ that is designed to accelerate up to 60 mA H{sup -} from 65 keV to 2.5 MeV [1]. A one millisecond pulse length at 60 Hz provides a 6% duty factor. The RFQ has now been built, conditioned at full duty factor and tested with beam. This paper will present results from the final installation, tuning and beam commissioning. Beam measurements include acceleration and transport efficiencies and transverse emittances. The LEBT optics were tuned for best results. Performance testing of the RF power distribution is also discussed here.
Date: August 16, 2002
Creator: Ratti, A.; Ayers, J.; Doolittle, L.; DiGennaro, R.; Gough, R.A.; Hoff, M. et al.
Partner: UNT Libraries Government Documents Department

High Intensity, Pulsed, D-D Neutron Generator

Description: Single ion-beam RF-plasma neutron generators are presented as a laboratory source of intense neutrons. The continuous and pulsed operations of such a neutron generator using the deuterium-deuterium fusion reaction are reported. The neutron beam can be pulsed by switching the RF plasma and/or a gate electrode. These generators are actively vacuum pumped so that a continuous supply of deuterium gas is present for the production of ions and neutrons. This contributes to the generator's long life. These single-beam generators are capable of producing up to 1E10 n/s. Previously, Adelphi and LBNL have demonstrated these generators' applications in fast neutron radiography, Prompt Gamma Neutron Activation Analysis (PGNAA) and Neutron Activation Analysis (NAA). Together with an inexpensive compact moderator, these high-output neutron generators extend useful applications to home laboratory operations.
Date: August 1, 2008
Creator: Williams, D. L.; Vainionpaa, J. H.; Jones, G.; Piestrup, M. A.; Gary, C. K.; Harris, J. L. et al.
Partner: UNT Libraries Government Documents Department

High Brightness Neutron Source for Radiography

Description: This research and development program was designed to improve nondestructive evaluation of large mechanical objects by providing both fast and thermal neutron sources for radiography. Neutron radiography permits inspection inside objects that x-rays cannot penetrate and permits imaging of corrosion and cracks in low-density materials. Discovering of fatigue cracks and corrosion in piping without the necessity of insulation removal is possible. Neutron radiography sources can provide for the nondestructive testing interests of commercial and military aircraft, public utilities and petrochemical organizations. Three neutron prototype neutron generators were designed and fabricated based on original research done at the Lawrence Berkeley National Laboratory (LBNL). The research and development of these generators was successfully continued by LBNL and Adelphi Technology Inc. under this STTR. The original design goals of high neutron yield and generator robustness have been achieved, using new technology developed under this grant. In one prototype generator, the fast neutron yield and brightness was roughly 10 times larger than previously marketed neutron generators using the same deuterium-deuterium reaction. In another generator, we integrate a moderator with a fast neutron source, resulting in a high brightness thermal neutron generator. The moderator acts as both conventional moderator and mechanical and electrical support structure for the generator and effectively mimics a nuclear reactor. In addition to the new prototype generators, an entirely new plasma ion source for neutron production was developed. First developed by LBNL, this source uses a spiral antenna to more efficiently couple the RF radiation into the plasma, reducing the required gas pressure so that the generator head can be completely sealed, permitting the possible use of tritium gas. This also permits the generator to use the deuterium-tritium reaction to produce 14-MeV neutrons with increases of yield of two orders of magnitude. The first fast neutron radiographic images were obtained using ...
Date: December 8, 2008
Creator: Cremer, J. T.; Piestrup, Melvin, A.; Gary, Charles, K.; Harris, Jack, L. Williams, David, J.; Jones, Glenn, E.; Vainionpaa, J. , H. et al.
Partner: UNT Libraries Government Documents Department

Ion-source and LEBT issues with the front-end systems for the Spallation Neutron Source

Description: The Front-End Systems (FES) of the Spallation Neutron Source (SNS) project are being built by Berkeley Lab and will deliver a pulsed 40-mA H{sup -} ion beam at 2.5 MeV energy to the subsequent Drift-Tube Linac. The FES accelerator components comprise an rf driven, volume-production, cesium-enhanced, multi-cusp Ion Source; an electrostatic Low-Energy Beam Transport (LEBT) that includes provisions for transverse focusing, steering, and beam chopping; an RFQ accelerator; and a Medium-Energy Beam Transport (MEBT) line. The challenges for Ion Source and LEBT design are the generation of a plasma suitable for creating the required high H{sup -} ion density, lifetime of the rf antenna at 6% duty factor, removal of the parasitic electron population from the extracted negative ions, and emittance conservation. The paper discusses these issues in detail and highlights key experimental results obtained so far.
Date: September 1, 2001
Creator: Keller, R.; Cheng, D.; DiGennaro, R.; Gough, R.A.; Greer, J.; Leung, K.N. et al.
Partner: UNT Libraries Government Documents Department

Progress with the SNS front-end systems

Description: The Front-End Systems (FES) of the Spallation Neutron Source (SNS) project have been described in detail elsewhere [1]. They comprise an rf-driven H{sup {minus}} ion source, electrostatic LEBT, four-vane RFQ, and an elaborate MEBT. These systems are planned to be delivered to the SNS facility in Oak Ridge in June 2002. This paper discusses the latest design features, the status of development work, component fabrication and procurements, and experimental results with the first commissioned beamline elements.
Date: May 1, 2001
Creator: Keller, R.; Abraham, W.; Ayers, J.J.; Cheng, D.W.; Cull, P.; DiGennaro, R. et al.
Partner: UNT Libraries Government Documents Department