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Paper Title Other Keywords Page
MOPA004 Status of Slip Stacking at Fermilab Main Injector beam-loading, injection, booster, emittance 347
  • K. Seiya, T. Berenc, B. Chase, J.E. Dey, I. Kourbanis, J.A. MacLachlan, K.G. Meisner, R.J. Pasquinelli, J. Reid, C.H. Rivetta, J. Steimel
    Fermilab, Batavia, Illinois
  Funding: Operated by Universities Research Association, Inc. for the U.S. Department of Energy under contract DE-AC02-76CH03000.

In order to increase proton intensity on anti proton production cycle of the Main Injector we are going to use the technique of 'slip stacking' and doing machine studies. In slip stacking, one bunch train is injected at slightly lower energy and second train is at slightly higher energy. Afterwards they are aligned longitudinally and captured with one rf bucket. This longitudinal stacking process is expected to double the bunch intensity. The required intensity for anti proton production is 8·1012 protons in 84 bunches. Beam studies of the slip stacking process have started and we have already established that the stacking procedure works as expected for a low beam intensity. In order to make this stacking process usable for higher intensity beam in standard mode of operation, we are working on high intensity beam and the development of the feedback and feed forward system is under way.

MPPE003 Monte Carlo Simulations of Thin Internal Target Scattering In CELSIUS simulation, scattering, electron, proton
  • Y.-N. Rao
    TRIUMF, Vancouver
  • D. Reistad
    TSL, Uppsala
  In the practical operation of the storage ring CELSIUS with the hydrogen pellet target, we simetimes observe a cooling phenomenon in the longitudinal phase space, that is, the circulating beam's phase space gets shrunk instead of blown up. This phenomenon occurs independently on the electron cooling. In this paper, we aim to investigate and interpret this phenomenon as well as the beam lifetime in the presence of hydrogen pellet target with and without rf and with and without electron cooling in CELSIUS using Monte Carlo simulations.  
MPPE006 Particle Distribution Function Forming in Nonlinear Systems octupole, quadrupole, focusing, lattice 985
  • S.N. Andrianov, S. Edamenko
    St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg
  Modern ion-optical systems are used in different fields of beam physics both independent facilities as consisting of largemachines. One of these destination is to create beams with a desired distribution of beams particles. Often there is a need to ensure a homogeneous distribution for a terminal beam phase portrait in a transverse configuration space. This is one of problems of nonlinear aberrations management. It is known that nonlinearity properties inhere to any beam lines. Such these nonlinearities have unremovable character, and their influence can be remove using only special nonlinear lattice elements, which are introduced artificially into the beam line. In this paper we suggest a procedure to find necessary nonlinear correcting control elements for purposive forming of beam particle distribution functions.  
MPPE008 Synthesis of Beam Lines with Necessary Properties quadrupole, focusing, simulation, octupole 1096
  • S.N. Andrianov
    St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg
  In this paper a new approach to the problem of synthesis of beam lines is discussed. Usually this problem can be overcome by the use of numerical simulation and optimal control theory methods. But this results in sufficiently great number of variable parameters and functions. Obviously, that this degrades quality of a modeling procedure. The suggested approach is demonstrated on a problem of a microprobe design problem. Essence of the problem is that necessary to design a high precision focusing system which satisfies some additional conditions. For solution of this problem we use an algebraic treatment based on Lie algebraic methods and computer algebra techniques. Using the symmetry ideology this approach allows rewriting beam properties to enough simple conditions for control parameters and functions. This leads a set of desired solutions and show results in some most suitable form. Moreover, this approach decreases the number of variable parameters.  
MPPE015 Non-Linear Ring Model Calibration with Frequency Analysis of Betatron Oscillations sextupole, lattice, resonance, betatron 1452
  • R. Bartolini
    Diamond, Oxfordshire
  • F. Schmidt
    CERN, Geneva
  A precise model of an accelerator ring is crucial to achieve ultimate performance both in synchrotron light sources and high energy synchrotrons. Algorithms have been developed to calibrate the linear model of the ring. They have been successfully applied experimentally to determine and correct the linear optics of the machine. More recently the Frequency Map Analysis has been used to model also the non-linear optics. We propose here a technique based on the fit of non-linear spectral lines to recover the non-linear driving terms and to compensate the non-linear field errors around the ring.  
MPPE021 Non-Linear Beam Transport System for the LENS 7 MeV Proton Beam octupole, proton, beam-transport, quadrupole 1704
  • W.P. Jones, D.V. Baxter, V.P. Derenchuk, T. Rinckel, K. A. Solberg
    IUCF, Bloomington, Indiana
  Funding: This work has been supported by the National Science Foundation under grants DMR-0220560 and DMR–0320627, by the Indiana 21st Century Science and Technology Fund, and by the Department of Defense.

A beam transport system has been designed to carry a high-intensity low-emittance proton beam from the exit of the RFQ-DTL acceleration system of the Indiana University Low Energy Neutron System (LENS)* to the neutron production target. The goal of the design was to provide a beam of uniform density over a 3cm by 3cm area at the target. Two octupole magnets** are employed in the beam line to provide the necessary beam phase space manipulations to achieve this goal. First order calculations were done using TRANSPORT and second order calculations have been performed using TURTLE. Second order simulations have been done using both a Gaussian beam distribution and a particle set generated by calculations of beam transport through the RFQ-DTL using PARMILA. Comparison of the design characteristics with initial measurements from the LENS commissioning process will be made.

*V.P. Derenchuk et al., "The LENS 7 MeV, 10mA proton Linac," these proceedings. **E. Kashy & B. Sherrill, Nuclear Instruments and Methods in Physics Research, B26 (1987) p. 610.

MPPE049 Sensitivity Study for Evaluating the Extracted Beam Parameters of the LLUMC Proton Therapy Synchrotron optics, emittance, proton, synchrotron 3046
  • G.H. Gillespie, W. Hill
    G.H. Gillespie Associates, Inc., Del Mar, California
  • G. Coutrakon, J. Hubbard, E. Sanders
    LLU/MC, Loma Linda, California
  The MINOS nonlinear constrained optimization program, working in concert with the beam optics code TRANSPORT, has been shown in recent work to provide a fast, efficient and reliable procedure for determining the parameters of the beam extracted from the LLUMC proton therapy synchrotron. MINOS and TRANSPORT work together as Modules of the Particle Beam Optics Laboratory (PBO Lab) software. The software was used to determine the parameters of the beam extracted from the synchrotron accelerator that best fit the extensive wire scanner profile data used to monitor the LLUMC proton therapy beamlines. In this paper additional constraints and optimizer variables are utilized with the procedure, in order to evaluate the sensitivity of the best fit extracted beam parameters to various assumptions. The methods used will be described and selected results from the study presented.  
MPPT019 Magnet Design for the ISIS Second Target Station Proton Beam Line dipole, quadrupole, proton, septum 1652
  • C.M. Thomas, D.C. Faircloth, S.J.S. Jago
    CCLRC/RAL/ISIS, Chilton, Didcot, Oxon
  The ISIS facility, based at the Rutherford Appleton Laboratory in the UK, is an intense source of neutrons and muons for condensed matter research. The accelerator facility delivers an 800 MeV proton beam of 2.5x1013 protons per pulse at 50 Hz to the present target station. As part of a facility upgrade, it is planned to share the source with a second, 10 Hz, target station. The beam line supplying this target will extract from the existing target station beam line. Electromagnetic Finite Element Modelling techniques have been used to design the magnets required to meet the specified beam line optics. Kicker, septum, dipole, quadrupole, and steering magnets are covered. The magnet design process, involving 2D and 3D modelling, the calculation of ideal shims and chamfers, choice of steel, design of conducting coils, handling of heating issues and eddy current effects, is discussed.  
MPPT031 Radiation Resistant Magnets for the RIA Fragment Separator radiation, quadrupole, dipole, sextupole 2200
  • A. Zeller, V. Blideanu, R.M. Ronningen, B. Sherrill
    NSCL, East Lansing, Michigan
  • R.C. Gupta
    BNL, Upton, Long Island, New York
  Funding: Supported in part by Michigan State University and the U.S. DOE.

The high radiation fields around the production target and the beam dump in the fragment separator at the Rare Isotope Accelerator requires that radiation resistant magnets be used. Because large apertures and high gradients are required for the quadrupoles and similar demanding requirements for the dipole and sextupoles, resistive coils are difficult to justify. The radiation heating of any materials at liquid helium temperatures also requires that superconducting versions of the magnets have low cold-masses. The final optical design has taken the practical magnets limits into account and sizes and fields adjusted to what is believed to be achievable with technology that is possible with sufficient R&D. Designs with higher obtainable current densities and having good radiation tolerances that use superconducting coils are presented, as well as the radiation transport calculations that drive the material parameters.

MPPT063 Optimized Analyzing Magnet for Measurements of Polarization of Gamma-Quants at 10 MeV polarization, electron, positron, scattering 3582
  • A.A. Mikhailichenko
    Cornell University, Department of Physics, Ithaca, New York
  We described here calculations and test of magnet for measurement of polarization of gammas by its helicity-dependent attenuation in magnetized iron. Magnet is a compact device which size is ~ten times smaller, than world wide analogues.  
MPPT071 The Lambertson Septum Magnet of the Spallation Neutron Source septum, extraction, vacuum, lattice 3847
  • J. Rank, Y.Y. Lee, W.J. McGahern, G. Miglionico, D. Raparia, N. Tsoupas, J.E. Tuozzolo, J. Wei
    BNL, Upton, Long Island, New York
  Funding: Work performed under contract for SNS, managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

In the Spallation Neutron Source, at Oak Ridge National Laboratory in Tennessee, multiple-stage injections to an accumulator ring increase intensity until a final extraction delivers the full proton beam to the target via transfer line. This extraction is achieved by a series of kicker elements and a thin septum Extraction Lambertson Septum Magnet. Here we discuss the lattice geometry, beam dynamics and optics, and the vacuum, electromagnetic and electromechanical design aspects of the SNS Extraction Lambertson Septum Magnet. Relevant datums are established. Beam optics is studied. Vector calculus is solved for pitch and roll angles. Fundamental magnet sections are depicted schematically. Coil, pole and yoke design calculations and electromagnetics optimization are presented.

TOAA006 Development of Superconducting Combined Function Magnets for the Proton Transport Line for the J-PARC Neutrino Experiments dipole, proton, quadrupole, alignment 495
  • T. Nakamoto, Y. Ajima, Y. Fukui, N. Higashi, A. Ichikawa, N. Kimura, T. Kobayashi, Y. Makida, T. Ogitsu, H. Ohhata, T. Okamura, K. Sasaki, M. Takasaki, K. Tanaka, A. Terashima, T. Tomaru, A. Yamamoto
    KEK, Ibaraki
  • M. Anerella, J. Escallier, G. Ganetis, R.C. Gupta, M. Harrison, A.K. Jain, J.F. Muratore, B. Parker, P. Wanderer
    BNL, Upton, Long Island, New York
  • T. Fujii, E. Hashiguchi, T. Kanahara, T. Orikasa
    Toshiba, Yokohama
  • Y. Iwamoto
    JAERI, Ibaraki-ken
  • T. Obana
    GUAS/AS, Ibaraki
  A second generation of long-baseline neutrino oscillation experiments has been proposed as one of the main projects at J-PARC jointly built by JAERI and KEK. Superconducting combined function magnets, SCFMs, will be utilized for the 50 GeV, 750 kW proton beam line for the neutrino experiment and an R&D program is in underway at KEK. The magnet is designed to provide a combined function of a dipole field of 2.6 T with a quadrupole field of 19 T/m in a coil aperture of 173.4 mm. A series of 28 magnets in the beam line will be operated DC in supercritical helium cooling below 5 K. A design feature of the SCFM is the left-right asymmetry of the coil cross section: current distributions for superimposed dipole- and quadrupole- fields are combined in a single layer coil. Another design feature is the adoption of glass-fiber reinforced phenolic plastic spacers to replace the conventional metallic collars. To evaluate this unique design, fabrication of full-scale prototype magnets is in progress at KEK and the first prototype will be tested at cold soon. This paper will report the development of the SCFMs.  
TPAT068 A Fast Faraday Cup for the Neutralized Drift Compression Experiment ion, plasma, simulation, electron 3765
  • A.B. Sefkow, R.C. Davidson, P. Efthimion, E.P. Gilson
    PPPL, Princeton, New Jersey
  • F.M. Bieniosek, J.E. Coleman, S. Eylon, W.G. Greenway, E. Henestroza, J.W. Kwan, P.K. Roy, D.L. Vanecek, W. Waldron, S. Yu
    LBNL, Berkeley, California
  • D.R. Welch
    ATK-MR, Albuquerque, New Mexico
  Funding: Research supported by the U.S. Department of Energy.

Heavy ion drivers for high energy density physics applications and inertial fusion energy use space-charge-dominated beams which require longitudinal bunch compression in order to achieve sufficiently high beam intensity at the target. The Neutralized Drift Compression Experiment-1A (NDCX-1A) at Lawrence Berkeley National Laboratory (LBNL) is used to determine the effective limits of neutralized drift compression. NDCX-1A investigates the physics of longitudinal drift compression of an intense ion beam, achieved by imposing an initial velocity tilt on the drifting beam and neutralizing the beam's space-charge with background plasma. Accurately measuring the longitudinal compression of the beam pulse with high resolution is critical for NDCX-1A, and an understanding of the accessible parameter space is modeled using the LSP particle-in-cell (PIC) code. The design and preliminary experimental results for an ion beam probe which measures the total beam current at the focal plane as a function of time are summarized.

TPAT094 Luminescence Beam Profile Monitor for the RHIC Polarized Hydrogen Jet Polarimeter proton, polarization, ion, monitoring 4293
  • N.P. Luciano, Y. Makdisi, A.N. Nass, P. Thieberger, D. Trbojevic, A. Zelenski
    BNL, Upton, Long Island, New York
  Funding: Work performed under Contract Number DE-AC02-98CH10886 with the auspicies of the US Deparment of Energy.

This is the second polarized proton run in Relativistic Heavy Ion Collider (RHIC) with a new polarized proton jet target used to provide accurate polarization measurements. The interactions between the stored polarized protons with the polarized jet target will produce, in addition to polarization, optical signals due to exited states of Hydrogen or other molecules, ions, or atoms. Additional lenses, optical window, optical analyzer, and the CCD camera are added to the system to allow transfer and detection of optical signals from the interaction chamber. Oxygen or other elements (impurities) could be mixed within the jet target and affect the accuracy of the polarization measurements. It is important to have continuous information of the jet content without affecting the polarization measurements. The optical signals coming from the exited states of molecules, ions, and atoms from the polarized proton beam interaction with the jet will provide that. In addition, the beam profile might be obtained.

TOAD004 The Possibility of Noninvasive Micron High Energy Electron Beam Size Measurement Using Diffraction Radiation radiation, electron, background, emittance 404
  • G.A. Naumenko, A. Potylitsyn
    Tomsk Polytechnic University, Physical-Technical Department, Tomsk
  • S. Araki, A. Aryshev, H. Hayano, V. Karataev, T. Muto, J.U. Urakawa
    KEK, Ibaraki
  • D. Cline, Y. Fukui
    UCLA, Los Angeles, California
  • R. Hamatsu
    TMU, Hatioji-shi,Tokyo
  • M.C. Ross
    SLAC, Menlo Park, California
  During the last years a noninvasive method for beam size measurement based on the optical diffraction radiation (ODR) has been in progress (P. Karataev, et al., Physical Review Letters 93, 244802 (2004). However this technique encounters with hard sensitivity limitation for electron energies larger than several GeV. For example, for SLAC conditions the sensitivity of this method is 4 orders smaller than an appropriate one. We suggest to use a "dis-phased" slit target, where two semi-planes are turned with respect to each other at a small "dis-phased" angle. In order to ensure the interference between the diverged radiation beams we use a cylindrical lens. This method has much better sensitivity and resolution. A "dis-phased" angle 10 milliradians gives the optimal sensitivity to 5 microns transversal beam size. The theoretical model for calculating the ODR radiation from such targets (including focusing by cylindrical lens) is presented. It is shown that the sensitivity of this method does not depend on the Lorenz-factor directly. The target with the "dis-phased" angle 6.2 milliradians and the slit width 425 microns was manufactured for experimental test. Some preliminary experimental results are presented.  
TPPE004 The Production of Negative Lithium Beams by Charge Exchange in Cesium Vapours ion, electron, ion-source, vacuum 898
  • M. Re, F. Chines, G. Cuttone, M. Menna, E. Messina
    INFN/LNS, Catania
  • J.-C. Bilheux, D.W. Stracener
    ORNL, Oak Ridge, Tennessee
  These measurements were carried out at the Holifield Radioactive Ion Beam Facility of the Oak Ridge National Laboratory (ORNL-HRIBF) by researchers from the Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), Catania, Italy and local staff. The Charge Exchange Cell (CEC) consisted of a vacuum chamber containing cesium vapours at a variable temperature, T, in which positive ions accelerated from an ion source were transformed into negative ones by collisions with the Cs atoms. The main goal of this test was to measure the production efficiency for 7Li- ions at different operating conditions, such as 7Li+ beam energy (5 to 55 keV) and Cs temperature (190 to 300 °C). Moreover, the efficiency measurements performed with a 6Li+ projectile beam gave clear indications about the isotopic shift effect. These results are useful to estimate the charge exchange efficiency for 8, 9Li, which will be the first radioactive beams to be produced at the EXCYT facility (EXotics with CYclotron and Tandem). The data showed that the charge exchange efficiency at the minimum energy suitable for beam handling (20-25 keV) is around 1%.  
TPPE015 The Effusive-Flow Properties of Target/Vapor-Transport Systems for Radioactive Ion Beam Applications ion, ion-source, cathode, electron 1422
  • Y. Kawai, G. Alton, Y. Liu
    ORNL, Oak Ridge, Tennessee
  Funding: Research at ORNL is supported by the U.S. DOE under contract DE-AC05-00OR22725 with UT-Battelle, LLC.

Radioactive atoms produced by the ISOL technique must diffuse from a target, effusively flow to an ion source, be ionized, be extracted, and be accelerated to research energies in a time commensurate with the lifetime of the species of interest. We have developed a fast valve system (closing time ~100 us) that can be used to accurately measure the effusion times of chemically active or inactive species through arbitrary geometry and size vapor transport systems with and without target material in the reservoir. The effusive flow times are characteristic of the system and thus serve as figures of merit for assessing the quality of a given vapor transport system as well as for assessing the permeability properties of a given target design. This article presents effusive flow data for noble gases flowing through a target reservoir and ion source system routinely used to generate radioactive species at the HRIBF with and without disks of 6 times and 10 times compressed Reticulated Vitreous Carbon Foam (RVCF) with the objective of determining the added delay time associated with each of these target matrices.

TPPE016 ISOL Targets Prepared with a New Paint Infiltration Coating Method ion, vacuum, electron 1508
  • Y. Kawai, G. Alton, J. O. Kiggans, D.W. Stracener
    ORNL, Oak Ridge, Tennessee
  Funding: Research at ORNL is supported by the U.S. DOE under contract DE-AC05-00OR22725 with UT-Battelle, LLC.

A new infiltration paint coating method has been developed for fabricating ISOL targets for radioactive ion beam applications. The technique has been shown to be inexpensive, fast, and almost universal for the uniform deposition of many refractory target materials onto the interior surfaces of complex geometry matrices, such as Reticulated-Vitreous-Carbon-Foam (RVCF). The process yields robust, highly permeable targets with fast diffusion and release properties. We demonstrate the viability of the technique for coating forms of RVCF compressed by factors of 6 and 10 with materials to form targets for use at high energy facilities such as RIA. The use of compressed RVCF, coated with an optimum thickness of target material, reduces target lengths to practical values, while preserving high permeability. We calculate thermal conductivities and diffusion for various targets on 6xRVCF and 10xRVCF.

TPPE018 Characterization of a Tubular Hot-Cavity Surface Ionization Source ion, ion-source, plasma, emittance 1581
  • Y. Liu, H. Z. Bilheux, Y. Kawai
    ORNL, Oak Ridge, Tennessee
  Funding: Managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725.

Elements with low ionization potentials can be efficiently ionized by positive surface ionization. It has been experimentally observed and theoretically shown that the ionization efficiency in a hot-cavity can be significantly higher than expected for the surface ionization mechanism. This is explained by the existence of a thermal plasma inside the cavity consisting of surface ionized ions and thermionic electrons. We have investigated the suggested ioniation mechanisms in a tubular hot-cavity surface ionization source where the area of the exit aperture is small compared with the tube inner surface. Thermal analyses of the tubular cavity and calculated mean number of wall collisions of a neutral particle in the cavity before escaping through the exit aperture are presented. Measured emittance and ionization efficiencies of various elements as a function of the cavity temperature for different cavity materials are discussed.

TPPE019 Laser Ion Source Development for ISOL Systems at RIA laser, ion, ion-source, radiation 1640
  • Y. Liu, C. Baktash, J.R. Beene, H. Z. Bilheux, C.C. Havener, H.F. Krause, D.R. Schultz, D.W. Stracener, C.R. Vane
    ORNL, Oak Ridge, Tennessee
  • K. Brueck, Ch. Geppert, T. Kessler, K. Wendt
    Johannes Gutenberg University Mainz, Mainz
  Funding: Managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725.

The isobaric purity of radioactive ion beams (RIBs) is of crucial importance to many experiments. Laser ion sources based on resonant photoionization have already proved to be of great value at existing ISOL RIB facilities. In these ion sources, ions of a selected isotope are produced by laser radiation via stepwise atomic resonant excitations followed by ionization in the last transition. Because each element has its own unique atomic energy levels, the resonant photoionization process can provide elemental selectivity of nearly 100%. We have initiated a research effort to develop a prototype laser ion source with the potential to achieve the high selectivity and high efficiency required for research with ISOL-generated RIBs at the Rare Isotope Accelerator (RIA). A pilot experiment has been conducted to demonstrate resonant photoionization of three atomic species using all-solid-state tunable Ti:Sapphire lasers. Three Ti:Sapphire lasers were provided by the University of Mainz and used in the experiment for three-photon resonant ionization of the elements. Laser generated Sn, Ni, and Ge ions have been successfully obtained in a hot-cavity laser ion source with overall efficiencies of 22%, 2.7%, and 3.3%, respectively.

TPPE021 Simulation Studies of Diffusion-Release and Effusive-Flow of Short-Lived Radioactive Isotopes ion, simulation, ion-source, vacuum 1739
  • Y. Zhang, G. Alton, Y. Kawai
    ORNL, Oak Ridge, Tennessee
  Funding: Research supported by the U.S. DOE under contract DE-AC05-00OR22725 with UT-Battelle, LLC.

Delay times associated with diffusion release from targets and effusive-flow transport of radioactive isotopes to ion sources are principal intensity limiters at ISOL-based radioactive ion beam facilities, and simulation studies with computer models are cost effective methods for designing targets and vapor transport systems with minimum delay times to avoid excessive decay losses of short lived ion species. A finite difference code, Diffuse II, was recently developed at the Oak Ridge National Laboratory to study diffusion-release of short-lived species from three principal target geometries. Simulation results are in close agreement with analytical solutions to Fick’s second equation. Complementary to the development of Diffuse II, the Monte-Carlo code, Effusion, was developed to address issues related to the design of fast vapor transport systems. Results, derived by using Effusion, are also found to closely agree with experimental measurements. In this presentation, the codes will be used in concert to make realistic estimations of intensities of a number of short-lived isotopes that are candidates for use in future nuclear physics and nuclear astrophysics experiments at the HRIBF.

TPPE027 Properties of Laser-Produced Highly Charged Heavy Ions for Direct Injection Scheme laser, plasma, ion, rfq 1976
  • K. Sakakibara, T. Hattori, N. Hayashizaki, T. Ito
    RLNR, Tokyo
  • H. Kashiwagi
    JAERI/ARTC, Gunma-ken
  • M. Okamura
    RIKEN, Saitama
  To accelerate highly charged intense ion beam, we have developed the Direct Plasma Injection Scheme (DPIS) with laser ion source. In this scheme an ion beam from a laser ion source is injected directly to a RFQ linac without a low energy beam transport (LEBT) and the beam loss in the LEBT can be avoided. We achieved high current acceleration of carbon ions (60mA) by DPIS with the high current optimized RFQ. As the next setp we will use heavier elements like Ag, Pb, Al and Cu as target in LIS (using CO2, Nd-YAG or other laser) for DPIS and will examine properties of laser-produced plasma (the relationship of between charge state and laser power density, the current dependence of the distance from the target, etc).  
TPPE030 A Method to Polarize Stored Antiprotons to a High Degree electron, antiproton, polarization, lattice 2158
  • A. Lehrach, S. Martin, F. Rathmann
    FZJ, Jülich
  • P. Lenisa
    INFN-Ferrara, Ferrara
  • I.N. Meshkov, A.O. Sidorin, A.V. Smirnov
    JINR, Dubna, Moscow Region
  • C. Montag
    BNL, Upton, Long Island, New York
  • E. Steffens
    University of Erlangen-Nürnberg, Physikalisches Institut II, Erlangen
  • C.-A. Wiedner
    UGS, Langenbernsdorf
  The PAX collaboration proposes a method to produce intense beams of polarized antiprotons. Polarized antiprotons can be produced in a storage ring by spin-dependent interaction in a purely hydrogen gas target. The polarizing process is based on spin transfer from the polarized electrons of the target atoms to the orbiting antiprotons. After spin filtering for about two beam lifetimes at energies of about 50-100 MeV using a dedicated large acceptance ring, the antiproton polarization would reach P=0.2-0.4. In the presentation, beside a description of the polarization technique and its potentiality, a description of the ideal characterstics of the antiproton polarizer will be given.


TPPE036 Progress of the BEPCII Linac Upgrade positron, electron, linac, gun 2416
  • G. Pei
    IHEP Beijing, Beijing
  BEPCII-an upgrade project of the BEPC is a factory type of e+e- collider. It requires its injector linac to have a higher beam energy (1.89 GeV) for on-energy injection and a higher beam current (40 mA e+ beam) for a higher injection rate (=50 mA/min.). The low beam emittance (1.6pmm-mrad for e+ beam, and 0.2pmm-mrad for 300 mA e- beam) and low beam energy spread (±0.5%) are also required to meet the storage ring acceptance. Hence we need a new electron gun system, a new positron source, a much higher power and more stable RF system with its phasing loops, and a new beam tuning system with orbit correction. Up to date, all system design and fabrication work have been completed. And in five months from May 1st of 2004, the positron production system–from the electron gun to the positron source, has been installed into the tunnel. In this paper, we will introduce major upgrades of each system, and present the recent beam commissioning.  
TPPE052 Characteristics of Electron Beam Produced by Magnetron Diode with a Secondary-Emission Cathode cathode, electron, gun, vacuum 3197
  • N.G. Reshetnyak, N. Aizatsky, A. Dovbnya, N.A. Dovbnya, V.V. Mytrochenko, V. Zakutin
    NSC/KIPT, Kharkov
  The beam parameters were investigated using an azimuth-sectionalized 8-channel Faraday cup and a 12-channel computer-aided measuring system. The magnetron diode had a cathode (40 mm in diameter) and a 15 mm anode-cathode gap. At a cathode voltage amplitude of 50 kV and a cathode magnetic field of ~1200 Oe, the diode generates a tubular electron beam with an outer diameter of 50 mm, an inner diameter of 44 mm, a beam current of ~50 A. The short time instability of the total beam current, and of the current from each of eight segments of the Faraday cup was estimated to be ~2 … 3%, and long time instability (3 hours) was 57 %. Azimuthal distribution of beam current was investigated versus the amplitude, distribution and direction of the magnetic field. At a cathode magnetic field of 1200 Oe, that falls off inhomogeneity in the vicinity of the Faraday cup down to ~800 Oe, the azimuthal beam current distribution has a ± (3 … 5)%. As the magnetic field strength increases up to ~1700 Oe in the region of beam emergence from the gun and the Faraday cup, the azimuthal inhomogeneity of the beam current increases up to ± (100 … 150)%.  
TPPE053 Design Issues for the ILC Positron Source positron, electron, photon, undulator 3230
  • V. Bharadwaj, Y.K. Batygin, R. Pitthan, D.C. Schultz, J. Sheppard, H. Vincke, J.W. Wang
    SLAC, Menlo Park, California
  • J.G. Gronberg, W. Stein
    LLNL, Livermore, California
  Funding: Work supported by Department of Energy contract DE-AC02-76SF00515.

A positron source for the ILC can be designed using either a multi-GeV electron beam or a multi-MeV photon beam impinging on a metal target. The major issues are: the drive beam, choice of target material, the design of the target station, the capture section, the target vault, and beam transport to the damping ring. In this paper, positron source parameters for the various schemes are outlined and the advantages and disadvantages of each scheme are discussed.

TPPP006 Beam-Beam Simulation Study with Parasitic Crossing Effect at KEKB luminosity, simulation, damping, beam-beam-effects 1033
  • M. Tawada, Y. Funakoshi, K. Ohmi
    KEK, Ibaraki
  KEKB is an asymmetric-energy, two-ring, electron-positron collider for B physics. Two beams collide at one interaction point with a finite crossing angle of 22 mrad. The bunch spacing has chosen to be 4 buckets (8 nsec) in most physics run of KEKB. While the shorter bunch spacing is necessary for a higher luminosity, the degradation of the specific luminosity by unknown reason is observed in 4 or 6 nsec spacing. In order to investigate whether parasitic crossing effect degrades a beam-beam performance, we have performed strong-strong beam-beam simulation with parasitic long-range beam-beam force. In this paper we present and discuss our simulation results.  
TPPP032 Proposal for a Multi-Use Test Beam Area in the SLAC B-Line linac, optics, quadrupole, emittance 2221
  • P. Emma, L.D. Bentson, R.A. Erickson, H. Fieguth, J. Seeman, A. Seryi
    SLAC, Menlo Park, California
  Funding: Work supported by U.S. Department of Energy contract DE-AC02-76SF00515.

With the impending construction of the Linac Coherent Light Source (LCLS) at SLAC, displacing the well-used Final Focus Test Beam (FFTB) area, there is growing interest in developing a new test beam facility, available during LCLS operations and located in the old B-Line tunnel at the end of the linac. The success of the Sub-Picosecond Pulse Source (SPPS) and the desire to preserve this capacity suggests a new beamline with similar or improved electron beam quality, including bunch length compression to 10 microns. Beam availability during LCLS operations requires a new 1.2-km bypass line connecting the 2/3-point of the linac with the B-Line. A second operating mode, with LCLS not in use, involves a trajectory directly from the end of the linac to the B-line. This feature provides the highest beam quality at 30 GeV, and also allows a possible third operational mode by deflecting a few of the very high-brightness 120-Hz, 14-GeV LCLS bunches at low rate (1-10 Hz) into the B-line. Finally, linear collider research can be carried out in a short final focus system at the end of the B-Line, capable of producing a 70-nm rms beam size. We describe a possible design for these systems.

TPPP040 Front-End Design Studies for a Muon Collider collider, simulation, proton, dipole 2610
  • R.C. Fernow, J.C. Gallardo
    BNL, Upton, Long Island, New York
  Funding: Work supported by U.S. Department of Energy.

Using muons instead of electrons is a promising approach to designing a lepton-lepton collider with energies beyond that available at the proposed ILC. At this time a self-consistent design of a high-luminosity muon collider has not been completed. However, a lot of progress has been made in simulating cooling and parts of other systems that could play a role in an eventual collider design. In this paper we look at front-end system designs that begin with a single pion bunch produced from a high power mercury target. We present ICOOL simulation results for phase rotation, charge separation, and pre-cooling of the muon beams. A design is presented for a single-frequency phase rotation system that can transmit 0.47 muons per incident proton on the target. A bent solenoid can be used for high-efficiency separation of the positive and negative muon beams.

TPPP047 New and Efficient Neutrino Factory Front-End Design proton, factory, bunching, linac 2986
  • J.C. Gallardo, J.S. Berg, R.C. Fernow, H.G. Kirk, R. Palmer
    BNL, Upton, Long Island, New York
  • D.V. Neuffer
    Fermilab, Batavia, Illinois
  • K. Paul
    Muons, Inc, Batavia
  Funding: Work supported by U.S. Department of Energy.

As part of the APS Joint Study on the Future of Neutrino Physics* we have carried out detailed studies of the Neutrino Factory front-end. A major goal of the new study was to achieve equal performance to our earlier feasibility studies** at reduced cost. The optimal channel design is described in this paper. New innovations included an adiabatic buncher for phase rotation and a simplified cooling channel with LiH absorbers. The linear channel is 295 m long and produces 0.17 muons per proton on target into the assumed accelerator transverse acceptance of 30 mm and longitudinal acceptance of 150 mm.

*APS Multi-Divisional Study of the Physics of Neutrinos, http://www.aps.org/neutrino/. **S.Ozaki, R.B.Palmer, M.Zisman and J.C.Gallardo, edts., Tech. Rep., BNL-52623 (2001), http://www.cap.bnl.gov/mumu/studyii/FS2-report.html.

TPPP055 Simultaneous Bunching and Precooling Muon Beams with Gas-Filled RF Cavities emittance, simulation, factory, collider 3295
  • K. Paul, R.P. Johnson, T.J. Roberts
    Muons, Inc, Batavia
  • Y.S. Derbenev
    Jefferson Lab, Newport News, Virginia
  • D.V. Neuffer
    Fermilab, Batavia, Illinois
  Funding: This work was supported in part by DOE SBIR grant DE-FG02-03ER83722.

High-gradient, pressurized RF cavities are investigated as a means to improve the capture efficiency, to effect phase rotation to reduce momentum spread, and to reduce the angular divergence of a muon beam. Starting close to the pion production target to take advantage of the short incident proton bunch, a series of pressurized RF cavities imbedded in a strong solenoidal field is used to capture, cool, and bunch the muon beam. We discuss the anticipated improvements from this approach to the first stage of a muon cooling channel as well as the requirements of the RF cavities needed to provide high gradients while operating in intense magnetic and radiation fields.

TPPT007 Application of Highly-Pure Copper Lining to Normal-Conducting RF Cavities for an Electron-Positron Super B Factory factory, resonance, linac, coupling 1051
  • T. Abe, T. Kageyama
    KEK, Ibaraki
  • Z. Kabeya, T. Kawasumi
    MHI, Nagoya
  • T. Nakamura, K. Tsujimoto
    Asahi Kinzoku Co., Ltd., Gifu
  • K. Tajiri
    Churyo Engineering Co., Ltd., Nagoya
  We apply a new copper lining with a high purity and a high electric conductivity to normal-conducting RF cavities for an electron-positron super B factory, in which four-times more beam current is required to be stored than in the present KEK B factory (KEKB). The lining is produced first by electroplating in an acid copper sulfate bath without brightener nor other organic additives, where the current is periodically reversed (‘‘PR process''). Its electric conductivity is so high as to be comparable to that of the highest-class oxygen-free copper. Then the copper surface is electropolished to make it smoother. There are two differences between our application and the previous one to the accelerator components for J-Parc. The first one is the lining thickness; our target of 120um is much thinner. The second one is that we have no mechanical polishing on the electroplated surface before electropolishing. In this paper, results of the quantitative estimations of the quality factor on the electroplated pillbox test cavity are reported together with microscale investigations of the copper surfaces.  
TPPT015 Coupler Matching Techniques for C-Band Accelerating Section linac, resonance, coupling, simulation 1431
  • K. Yokoyama, M. Ikeda, K. Kakihara, T. Kamitani, S. Ohsawa, T. Sugimura, T. T. Takatomi
    KEK, Ibaraki
  Research and development of the c-band accelerating section has proceeded since 2002. This paper reports the development of the second prototype accelerating section. The coupler iris with a 4 mm thick is thicker than the first prototype because of preventing the rf breakdown at the iris edge. The coupler has a single port and the coupler cell is the same length as the waveguide(WR-187). The coupler cavity diameter and the coupling iris were optimized by using the iteration of the rf measurement which is the nordal shift method.  
TPPT018 Tuning of 20MeV PEFP DTL proton, insertion, simulation, klystron 1598
  • M.-Y. Park, Y.-S. Cho, H.-S. Kim, H.-J. Kwon, K.T. Seol, Y.G. Song
    KAERI, Daejon
  Funding: This work is supported by the 21C Frontier R&D program in the Ministry of Science and Technology of the Korean government.

The PEFP (Proton Engineering Frontier Project) 20 MeV DTL have been constructing in KAERI site. The tuning goals for PEFP DTL are achieving the tank frequency as ± 5 kHz of designed resonant frequency and 1% of field profile through a tank. To tune the tank frequency 8 low power slug tuners per tank are fabricated and the tuning range is ±125 kHz per a tuner. Post couplers with tap to stabilize the field against the perturbation also are fabricated and will be installed every 3rd (1st tank) and 2nd (2,3,4th tank) drift tubes. We set up the bead perturbation measurement equipment as measuring the phase shift of a tank using network analyzer and LabView program. We are finalizing the tuning procedures and also the data calculation program. In this presentation we will show the overall features of the PEFP DTL tuning and discuss the measurement results.

TPPT025 Breakdown in RF Cavities vacuum, lattice, site, ion 1886
  • J. Norem, A. Hassanein, Z. Insepov, I. Konkashbaev
    ANL, Argonne, Illinois
  Funding: DOE

We present a simple model of breakdown in rf cavities. For most events this involves tensile stress and tensile strength, however other effects can also contribute. We discuss the effects of different materials, fatigue, high pressure gas, primary and secondary emission sites, local field enhancements, dark currents, secondary emission, work functions, magnetic fields, macro and microscopic fracture mechanisms high current densities, surface and subsurface defects, and astronomical power densities. While primarily devoted to normal conductors, this work also has consequences for superconducting rf surfaces.

TPPT038 Development of C-Band Accelerator Structure with Smooth Shape Couplers simulation, linac, positron, acceleration 2530
  • T. Sugimura, M. Ikeda, K. Kakihara, T. Kamitani, S. Ohsawa, T. T. Takatomi, K. Yokoyama
    KEK, Ibaraki
  The first C-band accelerator structure for the SuperKEKB injector linac has been operated in the beam line of e+/e- injector linac for KEKB/PF/PF-AR since September, 2003. A new accelerator structure will locate upstream of the first structure. The upstream structure is exposed to higher RF field than that of downstream structure. For the case of first structure, most of an RF breakdown occurs in an input coupler. In order to reduce a frequency of the breakdown, improvement of a coupler is required. In order to suppress a thermionic emission around the coupler iris, thick and smooth iris is adopted for the upstream structure. The development status of this type of upstream structure is described.  
TPPT052 Cryogenic, Magnetic and RF Performance of the ISAC-II Medium Beta Cryomodule at TRIUMF alignment, acceleration, coupling, ion 3191
  • R.E. Laxdal, K. Fong, A.K. Mitra, T.C. Ries, I. Sekachev, G. Stanford, V. Zviagintsev
    TRIUMF, Vancouver
  The medium beta section of the ISAC-II Heavy Ion Accelerator consists of five cryomodules each containing four quarter wave resonators and one superconducting solenoid. The first cryomodule has been designed, assembled and cold tested at TRIUMF. The cryomodule vacuum space shares the cavity vacuum and contains a mu-metal shield, an LN2 cooled, copper thermal shield, plus the cold mass and support system. The bulk niobium cavities are fitted with an LN2 cooled coupling loop fed in series from the side thermal shield and a tuner plate coupled to an out-of-vacuum linear servo motor. All cavities have been locked at the ISAC-II frequency and gradient for extended periods. This paper will report the cryogenic and rf test results from the three cold tests. Of note are measurements of the magnetic field in the cryomodule and estimations of changes in the magnetic field during the test due to trapped flux in the solenoid and magnetization of the environment.  
TPPT062 High Power Test of the Prototype Cryomodule for ADS Superconducting Linac linac, klystron, radiation, feedback 3579
  • E. Kako, S. Noguchi, N. Ohuchi, T. Shishido, K. Tsuchiya
    KEK, Ibaraki
  • N. Akaoka, H. Kobayashi, N. Ouchi
    JAERI/LINAC, Ibaraki-ken
  • E. Chishiro, T. Hori, M. Nakata, M. Yamazaki
    JAERI, Ibaraki-ken
  A prototype cryomodule containing two 9-cell superconducting cavities of beta=0.725 and fo=972MHz had been constructed under the collaboration of Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK) on the development of superconducting LINAC for Accelerator Driven System (ADS). Cool-down tests to 2.0K of the cryomodule and high power tests with a 972MHz pulsed klystron have been successfully carried out. Rf power of 350kW in a pulsed operation of 3msec and 25Hz was transferred to the nine-cell cavity through an input coupler. Accelerating gradients of about 14MV/m higher than the specification (10MV/m) were achieved in both cavities. Design and performance of the prototype cryomodule and the test results with high rf power will be reported.  
TPPT088 Power Dependence of the RF Surface Resistance of MgB2 Superconductor laser, superconductivity, vacuum, superconducting-RF 4215
  • T. Tajima, A. Findikoglu, A.J. Jason, F.L. Krawczyk, F. M. Mueller, A. H. Shapiro
    LANL, Los Alamos, New Mexico
  • R.L. Geng, H. Padamsee, A.S. Romanenko
    Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York
  • B. Moeckly
    STI, Santa Barbara, California
  MgB2 is a superconducting material that has a transition temperature (Tc) of ~40 K. Recently, it has been shown at 4 K, liquid helium temperature, that the surface RF resistance can be lower than Nb that has the Tc of 9.2 K and has been used for most superconducting RF cavities in the past decades. One of the problems with other high-Tc materials such as YBCO was its rapid increase in RF surface resistance with higher surface magnetic fields. Recently, we have shown that MgB2 shows little increase up to about 120 Oe, equivalent of an accelerating field of about 3 MV/m. The highest field tested was limited by available power. This result is encouraging and has made us consider fabricating a cavity coated with MgB2 and test it. Also, there might be a potential that this material has a higher critical magnetic field that enables the cavity to run at a higher gradient than Nb cavities.  
TOPA007 Proton Acceleration and High-Energy Density Physics from Laser Foil Interactions proton, acceleration, ion, electron 573
  • P.A. Norreys
    CCLRC/RAL, Chilton, Didcot, Oxon
  • F.N. Beg
    UCSD, La Jolla, California
  • A.E. Dangor, K.M. Krushelnick, M. Wei
    Imperial College of Science and Technology, Department of Physics, London
  • M. Tatarakis
  • M. Zepf
    Queen's University of Belfast, Belfast, Northern Ireland
  Intense laser plasma interactions have long been shown to be a source of very energetic ions - from the first experiments in the 1970's. However, there has been a recent revival of interest in the production of protons and ions from the such plasmas - primarily from the observation of collimated beams of protons and heavier ions which were observed at the rear thin foil targets irradiated by ultra-high intensity laser pulses (such that I > 1018 W/cm2). These ion beams have unique properties which may make them suitable for a variety of applications such as for probing high density plasmas, for fast ignition in inertial confinement fusion, as an ion source for subsequent acceleration stages in a particle accelerator or potentially for medical applications. Recent experimental results will be reviewed and the potential for such future applications will be highlighted.  
TOPD001 SC Cyclotron and RIB Facilities in Kolkata cyclotron, ion, linac, rfq 89
  • B. Sinha, R.K. Bhandari, A. Chakrabarti
    DAE/VECC, Calcutta
  The superconducting cyclotron under construction at this Centre has bending limit (K-bend) of 520 and focusing limit (K-foc) of 160. It is being constructed, primarily, for nuclear physics experiments with heavy ion beams at intermediate energies. The 100-ton main magnet is currently in the commissioning phase with the main coil already at 4.2K temperature. Magnetic field measurements will be carried out over the next several months. All other systems of the cyclotron are in an advanced stage of fabrication or development. We plan to start assembly of the complete cyclotron around the end of 2005. In the phase-I of the project one beam line has been provided. Construction of three more beam lines and various experimental facilities for nuclear physics as well as irradiation experiments has also been funded and the work is well on its way. An ISOL type Radioactive Ion Beam (RIB) facility is being built with the existing K=130 room temperature cyclotron, VEC, as the primary beam source. In-beam RIB production as well as release measurements have been initiated using the VEC beam. The two-ion-source charge breeder consists of a surface ion source and a 6.4 GHz ECR source. The latter has been commissioned. A low beta RFQ to accelerate RIBs to 86 keV/u energy is being fabricated and the cold model tests completed. Design of first three linac tanks, for acceleration up to 400 keV/u, has been finalized and cold model for the first tank has been fabricated. In this talk status of both the projects will be presented.  
TOPD004 RIB Facility at VECC Kolkata–A Status Report rfq, linac, ion, ion-source 395
  • A. Chakrabarti, R.K. Bhandari
    DAE/VECC, Calcutta
  The status of the Radioactive Ion Beam (RIB) facility being built at VECC, Kolkata will be presented. The facility is being built around the existing K=130 cyclotron and will be installed in one of the existing experimental caves. The scheme is to use proton and alpha particles from the cyclotron on a thick production target placed inside an integrated surface ion-source. Radioactive ions with charge state q=1+ extracted from the target-ion-source are to be injected into an on-line ECRIS "charge breeder" for further ionization to q=n+. The 1keV/u, q/A=1/16, RIB of interest will be selected in an isotope separator downstream of the ECRIS and accelerated initially to about 86 keV/u in a Radio Frequency Quadrupole (RFQ) linac and subsequently to about 400 keV/u in three IH-Linac tanks. Since RIB development is R&D intensive, it has been decided to build at first all the basic building blocks and to carry out simultaneously thick target R&D and release measurements using the existing He-jet ISOL facility. Future expansion for further upgradation of energy has been planned. The design of the facility and some recent results will be presented.  
WPAE010 Neutron Flux and Activation Calculations for a High Current Deuteron Accelerator ion, vacuum, ion-source, simulation 1192
  • A. Coniglio, M.P. Pillon, S. Sandri
    ENEA C.R. Frascati, Frascati (Roma)
  • M. D'Arienzo
    CNR/RFX, Padova
  Neutron analysis of the first Neutral Beam (NB) for the International Thermonuclear Experimental Reactor (ITER) was performed to provide the basis for the study of the following main aspects: personnel safety during normal operation and maintenance, radiation shielding design, transportability of the NB components in the European countries. The first ITER NB is a medium energy light particle accelerator. In the scenario considered for the calculation the accelerated particles are negative deuterium ions with maximum energy of 1 MeV. The average beam current is 13.3 A. To assess neutron transport in the ITER NB structure a mathematical model of the components geometry was implemented into MCNP computer code (MCNP version 4c2. "Monte Carlo N-Particle Transport Code System." RSICC Computer Code Collection. June 2001). The neutron source definition was outlined considering both D-D and D-T neutron production. FISPACT code (R.A. Forrest, FISPACT-2003. EURATOM/UKAEA Fusion, December 2002) was used to assess neutron activation in the material of the system components. Radioactive inventory and contact dose rate were assessed considering the potential operative scenarios.  
WPAE018 Performance Tests of Survey Instruments Used in Radiation Fields Around High-Energy Accelerators radiation, simulation, shielding, photon 1595
  • S. Mayer, D. Forkel-Wirth, M. Fuerstner, H.G. Menzel, S. Roesler, C. Theis, H. Vincke
    CERN, Geneva
  Measurements of ambient dose equivalent in stray radiation fields behind the shielding of high-energy accelerators are a challenging task. Several radiation components (photons, neutrons, charged particles), spanning a wide range of energies, contribute to the total dose equivalent. In routine-measurements, the total dose equivalent is obtained by the combination of several radiation detectors. Ionisation chambers, which are sensitive to all radiation components, are employed together with so-called REM counters, which are responding mainly to neutrons. The total dose equivalent is correctly assessed provided that the response is interpreted carefully by using appropriate corrections and calibration factors. For this reason measurements were carried out in a high-energy reference field at CERN, which allows one to study the response of the different detectors in a mixed radiation field under controlled conditions. In addition, the field was simulated by Monte Carlo simulations. The outcome of these studies serves on one hand as a basis for quality assurance and improves on the other hand the knowledge of the instrument’s response for future applications at the LHC.  
WPAE022 Progress on the Liquid Hydrogen Absorber for the MICE Cooling Channel vacuum, scattering, focusing, acceleration 1772
  • M.A.C. Cummings
    Northern Illinois University, DeKalb, Illinois
  • S. Ishimoto
    KEK, Ibaraki
  This report describes the progress made on the design of the liquid hydrogen absorber for the international Muon Ionization Cooling Experiment (MICE). The absorber consists of a 21-liter vessel that contains liquid hydrogen (1.5 kg) or liquid helium (2.63 kg). The cryogen vessel is within the warm bore of the superconducting focusing magnet for the MICE. The purpose of the magnet is to provide a low beam beta region within the absorber. For safety reasons, the vacuum vessel for the hydrogen absorber is separated from the vacuum vessel for the superconducting magnet and the vacuum that surrounds the RF cavities or the detector. The absorber has two 300 mm-diameter thin aluminum windows. The vacuum vessel around the absorber has a pair of thin aluminum windows that separate the absorber vacuum space from adjacent vacuum spaces. The absorber will be cooled down using a heat exchanger that is built into the absorber walls. Liquid nitrogen is used to cool the absorber to 80 K. Liquid helium completes the absorber cool down and condenses hydrogen in the absorber. The absorber may also be filled with liquid helium to measure muon cooling in helium.  
WPAE037 Deformation Monitoring of the Spallation Neutron Source (SNS) Tunnels monitoring, SNS, survey, alignment 2509
  • J.J. Error, D.R. Bruce, J.J. Fazekas, S.A. Helus, J.R. Maines
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

The SNS Project is a 1.4 MW accelerator-based neutron source located at Oak Ridge National Laboratory in Oak Ridge, Tennessee. For shielding purposes, a 17 foot berm of native soil has been constructed on top of the accelerator tunnel system. This backfill has caused ongoing settlement of the tunnels. The settlement has been monitored by the SNS Survey and Alignment Group at regular intervals, in order to discover the patterns of deformation, and to determine when the tunnels will be stable enough for precise alignment of beam line components. The latest monitoring results indicate that the settlement rate has significantly decreased. This paper discusses the techniques and instrumentation of the monitoring surveys, and provides an analysis of the results.

WPAE039 Optical Tooling and its Uses at the Spallation Neutron Source (SNS) alignment, SNS, laser, instrumentation 2577
  • S.A. Helus, D.R. Bruce, J.J. Error, J.J. Fazekas, J.R. Maines
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

Optical tooling has been a mainstay of the accelerator alignment community for decades. Even now in the age of electronic survey equipment, optical tooling remains a viable alternative, and at times the only alternative. At SNS, we combine traditional optical tooling alignment methods, instrumentation, and techniques, with the more modern electronic techniques. This paper deals with the integration of optical tooling into the electronic survey world.

WPAE040 Comparison of Techniques for Longitudinal Tuning of the SNS Drift Tube Linac simulation, linac, SNS, Spallation-Neutron-Source 2616
  • D.-O. Jeon
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

It is important to bring the cavity field amplitude and phase to the design values for a high intensity linac such as the Spallation Neutron Source (SNS)linac. A few techniques are available, such as the longitudinal acceptance scan and phase scan. During SNS linac commissioning, tuning of cavities was conducted using the acceptance scan and phase scan technique based on multiparticle simulations. The two techniques are compared.

WPAE044 An Alignment of J-PARC Linac alignment, linac, synchrotron, survey 2851
  • T. Morishita, H. Ao, T. Ito, A. Ueno
    JAERI/LINAC, Ibaraki-ken
  • K. Hasegawa
    JAERI, Ibaraki-ken
  • M. Ikegami, C. Kubota, F. Naito, E. Takasaki, H. Tanaka, K. Yoshino
    KEK, Ibaraki
  J-PARC linear accelerator components are now being installed in the accelerator tunnel, whose total length is more than 400 m including the beam transport line to RCS (Rapid Cycling Synchrotron). A precise alignment of accelerator components is essential for a high quality beam acceleration. In this paper, planned alignment schemes for the installation of linac components, the fine alignment before beam acceleration, and watching the long term motion of the building are described. Guide points are placed on the floor, which acts as a reference for the initial alignment at the installation and also as a relay point for the long surveying network linking at the fine alignment. For a straight line alignment, the wire position sensor is placed on the offset position with respect to the beam center by a target holder, then a single wire can cover the accelerator cavities and the focusing magnets at the DTL-SDTL section (120m). The hydrostatic levering system (HLS) is used for watching the floor elevation (changes) over the long period.  
WPAE054 Irradiation Effects on RIA Fragmentation Cu Beam Dump ion, heavy-ion, radiation, simulation 3265
  • S. Reyes, L. Ahle, J.L. Boles, W. Stein
    LLNL, Livermore, California
  • B.D. Wirth
    UCB, Berkeley, California
  Funding: U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

Within the scope of conceptual R&D activities in support of the Rare-Isotope Accelerator (RIA) facility, high priority is given to the development of high-power fragmentation beam dumps. A pre-study was made of a static water-cooled Cu beam dump that can meet requirements for a 400 MeV/u uranium beam. The issue of beam sputtering was addressed and found to be not a significant issue. Preliminary radiation transport simulations show significant damage (dpa) in the vicinity of the Bragg peak of uranium ions. Experimental data show that defects in Cu following neutron or high-energy particle irradiation tend to saturate at doses between 1 and 5 dpa, and this saturation in defect density also results in saturation of mechanical property degradation. However, effects of swift heavy ion irradiation and the production of gaseous and solid transmutant elements still need to be addressed. Initial calculations indicate that He concentrations on the order of 100 appm are produced in the beam dump after several weeks of continuous operation and He embrittlement should be a concern. Recommendations are made for further investigation of Cu irradiation effects RIA-relevant conditions.

WPAE062 AC Power Supply for Wobbler Magnet of the MC-50 Cyclotron power-supply, cyclotron, ion, radiation 3576
  • Y.-S. Kim, J.-S. Chai
    KIRAMS, Seoul
  • C.W. Chung, H.-G. Lee, W.W. Lee, K.-H. Park
    PAL, Pohang, Kyungbuk
  • B.-K. Kang
    POSTECH, Pohang, Kyungbuk
  The MC-50 cyclotron (k=50) produces the ion beam for nuclear physics, chemistry, and applied researches in Korea. It has a small beam diameter with Gaussian beam shape, whereas many users want a beam irradiation on a large target. A wobbler magnet and an AC power supply were designed and constructed to meet the users’ requirement. The power supply has two independently operating channels for the vertical and horizontal coils of the wobbler magnet. The frequency of the AC power supply for both coils is programmable from 1 to 20 Hz in a step of 1 Hz, and the maximum rms output current is 12 A. Various properties of the power supply and experimental results are given in the paper.  
WPAP012 Preliminary Results on Beam Dynamics of Laser Pulse Shaping Effects in SPARC emittance, laser, electron, simulation 1315
  • M. Boscolo, M. Ferrario, M.  Migliorati
    INFN/LNF, Frascati (Roma)
  • F. Castelli, S. Cialdi, A.F. Flacco
    INFN-Milano, Milano
  In a photoinjector system the role played by the laser pulse shaping in achieving high quality electron beam is crucial, as it determines the distribution dependent space charge effects in the early stages of the acceleration. A dedicated code to simulate pulse shaping in a laser system and able to generate the corresponding initial electron beam distribution has been developed. Realistic deviations from the ideal flat top pulse give for example a ramp or multi-peaks shape with a raletive rise time, plateau deformation and ripples. The beam dynamics of electron beams with different initial temporal pulse characteristics along the SPARC photoinjector has also been studied with the code PARMELA. More exotic pulse shaping are also discussed. The study presented here gives some indications on the tolerances of the laser beam characteristics for the electron beam quality preservation.  
WPAP013 Magnesium Film Photocathodes for High Brilliance Electron Injectors laser, cathode, gun, electron 1350
  • F. Tazzioli, G. Gatti, C. Vicario
    INFN/LNF, Frascati (Roma)
  • I. Boscolo, S. Cialdi
    INFN-Milano, Milano
  • L. Cultrera, A. Perrone
    Lecce University, Lecce
  • S. Orlanducci, M.L. Terranova
    Università di Roma II Tor Vergata, Roma
  • M. Rossi
    Rome University La Sapienza, Roma
  Advanced high brilliance electron injectors require photocathodes having low thermal emittance, high quantum efficiency (QE) and prompt response. They should be easy to handle and capable of working in the very high electric fileds of a RF gun. Magnesium films deposited by laser ablation and sputtering techniques are discussed and QE measurements are presented.  
WPAP016 High Brightness Electron Gun for X-Ray Source electron, focusing, injection, brightness 1488
  • S. Ohsawa, M. Ikeda, T. Sugimura, M. Tawada
    KEK, Ibaraki
  • Y. Hozumi
    GUAS/AS, Ibaraki
  • K. Kanno
    AET Japan, Inc., Kawasaki-City
  A new electron-gun system is under development in order to increase X-ray from a rotating target. In commercial X-ray sources electron beams usually hit targets at the outer part. Owing to deformation by centrifugal force, there has been a limit on electron beam intensities. In order to overcome this difficulty, we adopted a new injection system which strikes inside of a ring-shape projection on a rotating target. It has an advantage in that heated-up points have supports back side against centrifugal force. This merit allows us to raise electron beam to give stronger X-rays.  
WPAP028 Modes of Electron Beam Generation in a Magnetron Diode with a Secondary-Emission Cathode cathode, gun, electron, vacuum 2027
  • V. Zakutin, A. Dovbnya, N.G. Reshetnyak
    NSC/KIPT, Kharkov
  Experiments have shown that the electron current direction can be varied along the diode axis or perpendicular to the axis, depending on the longitudinal magnetic field amplitude and distribution. The diode had a copper cathode diameter 40 mm and 15 mm anode-cathode gap. Several modes of electron beam generation are realized, namely, open, closed, and intermediate. In the first case, at a cathode magnetic field of ~ 1200 Oe, that falls off approaching the diode output down, and at a cathode voltage of 50 kV, the diode generates a tubular electron beam of a current 50 A and the anode current was about 1 % of the beam current. In the second case, the electron current was going to the anode, the secondary-emission multiplication of electrons being retained. At a cathode voltage of ~ 45 kV, the anode current was ~ 5 A, and the beam current was practically absent. This was attained by decreasing the magnetic field to ~ 1.11.2 of the Hell field value and by increasing the magnetic field towards the diode output. In the intermediate mode with a cathode voltage of ~ 45 kV the direct beam current measured was ~ 5 A, and the anode current was ~ 7 A.  
WPAP034 Positron Emulator for Commissioning ILC Positron Source positron, electron, damping, linac 2321
  • H. Wang, W. Gai, K.-J. Kim, W. Liu
    ANL, Argonne, Illinois
  Funding: U.S. DOE.

It is apparent that the gamma-ray based positron source components including positron linac and damping rings for ILC can not be easily commissioned until the electron beam is fully conditioned at high energies (> 150 GeV). In this paper, we discuss a scheme that could use a short and energetic electron beam scattered through a set of carefully selected targets to simulate certain behaviors of the positron beam, such as beam emittance and energy spread. The basic idea is to make the phase space distribution of the scattered electron beam to reflect certain aspects of the positron beam distributions. Subsequently, the positron source elements such as capture optics, linacs and even damping ring could be effectively commissioned before ILC colliding electron beam is ready. The simulation results using EGS4 for beam scattering and PARMELA for beam dynamics are presented.

WPAT027 Recent Results from the X-Band Pulsed Magnicon Amplifier electron, plasma, gun, vacuum 1979
  • O.A. Nezhevenko, V.P. Yakovlev
    Omega-P, Inc., New Haven, Connecticut
  • A.W. Fliflet, S.H. Gold
    NRL, Washington, DC
  • J.L. Hirshfield, M.A. LaPointe
    Yale University, Physics Department, New Haven, CT
  • A.K. Kinkead
  Funding: Research supported by the Department of Energy, Office of High Energy Physics, and the Office of Naval Research.

A frequency-doubling magnicon amplifier at 11.4 GHz has been designed and built as the prototype of an alternative microwave source for the Next Linear Collider project, and to test high power RF components and accelerating structures. The tube is designed to produce ~60 MW, ~1.2 microsecond pulses at 58% efficiency and 59 dB gain, using a 470 kV, 220 A, 2 mm-diameter beam. In the first tests the output power was limited to a level of 26 MW in a 200 nsec pulse. This limitation was caused by the oscillations in the tube collector. Experimental results of the magnicon tests with the new collector are presented in this paper

WPAT029 The RF Experimental Program in the Fermilab MUCOOL Test Area linac, background, electron, site 2104
  • J. Norem
    ANL, Argonne, Illinois
  • A. Bross, A. Moretti, Z. Qian
    Fermilab, Batavia, Illinois
  • R.P. Johnson
    Muons, Inc, Batavia
  • D. Li, M.S. Zisman
    LBNL, Berkeley, California
  • R.A. Rimmer
    Jefferson Lab, Newport News, Virginia
  • R. Sandstrom
    CUI, Geneva
  • Y. Torun
    IIT, Chicago, Illinois
  Funding: DOE

The rf R&D program for high gradient, low frequency cavities to be used in muon cooling systems is underway in the Fermilab Muon Test Area. Cavities at 805 and 201 MHz are used for tests of conditioning techniques, surface modification and breakdown studies. This work has the Muon Ionization Cooling Experiment (MICE) as its immediate goal and efficient muon cooling systems for neutrino sources and muon colliders as the long term goal. We study breakdown, and dark current productions under a variety of conditions.

WPAT048 Solid State Modulators for the International Linear Collider (ILC) linear-collider, collider, power-supply, controls 2998
  • M.A. Kempkes, N. Butler, J.A. Casey, M.P.J. Gaudreau, I. Roth
    Diversified Technologies, Inc., Bedford
  Diversified Technologies, Inc. is developing two solid state modulator designs for the ILC under SBIR funding from the DOE. The first design consists of a 150 kV hard switch. The key development in this design is the energy storage system, which must provide 25 kJ per pulse, at very tight voltage regulation over the 1.5 millisecond pulse. DTI’s design uses a quasi-resonant bouncer (with a small auxiliary power supply and switch) to maintain the voltage flattop, eliminating the need for massive capacitor banks. The second design uses a solid state Marx bank, with ~10 kV stages, to drive the ILC klystron. In this design, staggered turn-on of the Marx stages provides voltage regulation without the need for large capacitor banks. This paper will discuss design tradeoffs, power supply and control considerations, and energy storage requirements and alternatives for both designs.  
WPAT072 A 1.3GHz Inductive Output Tube for Particle Accelerators electron, gun, cathode, synchrotron 3883
  • E. Sobieradzki, A.E. Wheelhouse
    e2v technologies, Chelmsford, Essex
  There is an increasing requirement for RF power sources in the L-band frequency range for operation in particle accelerators. The paper describes the development and presents test results of a new inductive output tube (IOT) for use at 1.3GHz. A target specificationof 16kW cw output power at an efficiency of 60% was set. The paper discusses progress to date having used an electron gun geometry that minimizes transit time effects in the cathode to grid gap.  
WPAT079 Design of a Direct Converter for High Power, RF Applications feedback, booster, radio-frequency, synchrotron 4033
  • D. Cook, M. Catucci, J. Clare, P. W. Wheeler
    University of Nottingham, Nottingham
  • J.S. Przybyla
    EEV, Chelmsford, Essex
  Funding: Particle Physics and Astronomy Research Council.

This paper is concerned with a new type of power supply for high power RF applications for CW operation. The converter is a direct topology operating with a high frequency (resonant) link. Switching losses are minimised by switching at zero current. High operating frequency allows for minimised transformer and filter size. Advantages of this topology over conventional approaches are discussed, along with the potential problems and proposed solutions. Recently, considerable interest has been shown in direct converter topologies as an alternative topology in motor drive applications. This approach offers advantages such as reduced energy storage and higher energy density compared to conventional topologies. The work presented in this paper capitalises on these advantages in other fields, namely power conversion for RF supplies. The RF power needs to be stable and predictable such that any variation has a limited impact on the accelerated beam quality. In order to meet the required output voltage specification such designs require output filters with consequent energy storage. Management of this energy in the event of a fault is necessary if destruction of the tube is to be avoided.

WPAT091 Fabrication and Final Field Tuning of Copper Cavity Models for a High-Current SRF ERL at 703.75 MHz linac 4257
  • M.D. Cole, A. Burger, M. Falletta, D. Holmes, E. Peterson, R. Wong
    AES, Medford, NY
  • I. Ben-Zvi
    BNL, Upton, Long Island, New York
  Advanced Energy Systems is currently under contract to BNL to fabricate a five cell superconducting cavity and cryomodule for the RHIC eCooler SRF Energy Recovery Linac (ERL) program.* The cavity is designed and optimized for ampere class SRF ERL service. As part of this program, we have fabricated two low power copper models of the RF cavities. During the fabrication process a series of frequency measurements were made and compared to the frequency expected at that point in the fabrication process. Where possible, the cavity was modified either before or during, the next fabrication step to tune the cavity frequency toward the target frequency. Following completion of the cavities they were tuned for field flatness and frequency. This paper will review the measurements made, frequency tuning performed, and discuss discrepancies between the expected and measured results. We will also review the as fabricated field profiles and the results of the tuning steps. Further, the cost and benefits of extensive in process tuning will be discussed from an industrial perspective.

*Electron cooling of RHIC, Ilan Ben-Zvi, these proceedings.

WPAT092 Fabrication Tuning of Four 748.5 MHz Single Cell SRF Booster Cavities for a 100 mA SRF FEL Injector booster 4272
  • M.D. Cole, E. Peterson, J. Rathke, T. Schultheiss
    AES, Medford, NY
  Funding: This work is supported by NAVSEA, NSWC Crane, the Office of Naval Research, and the DOD Joint Technology Office.

Advanced Energy Systems has recently completed the fabrication of four 748.5 MHz single cell superconducting cavities which are to be used in the JLAB FEL SRF Injector Test Stand. During the fabrication process a series of frequency measurements were made and compared to the frequency expected at that point in the fabrication process. Where possible, the cavity was modified either before or during, the next fabrication step to tune the cavity frequency toward the target frequency. The target frequency is calculated making a series of assumptions about the frequency effects of subsequent fabrication and processing steps.

ROAC004 High Gradient Performance of NLC/GLC X-Band Accelerating Structures linear-collider, collider, vacuum, linac 372
  • S. Doebert, C. Adolphsen, G.B. Bowden, D.L. Burke, J. Chan, V.A. Dolgashev, J.C. Frisch, R.K. Jobe, R.M. Jones, R.E. Kirby, J.R. Lewandowski, Z. Li, D.J. McCormick, R.H. Miller, C.D. Nantista, J. Nelson, C. Pearson, M.C. Ross, D.C. Schultz, T.J. Smith, S.G. Tantawi, J.W. Wang
    SLAC, Menlo Park, California
  • T.T. Arkan, C. Boffo, H. Carter, I.G. Gonin, T.K. Khabiboulline, S.C. Mishra, G. Romanov, N. Solyak
    Fermilab, Batavia, Illinois
  • Y. Funahashi, H. Hayano, N. Higashi, Y. Higashi, T. Higo, H. Kawamata, T. Kume, Y. Morozumi, K. Takata, T. T. Takatomi, N. Toge, K. Ueno, Y. Watanabe
    KEK, Tsukuba, Ibaraki
  Funding: Work Supported by DOE Contract DE-AC02-76F00515.

During the past five years, there has been an concerted effort at FNAL, KEK and SLAC to develop accelerator structures that meet the high gradient performance requirements for the Next Linear Collider (NLC) and Global Linear Collider (GLC) initiatives. The structure that resulted is a 60-cm-long, traveling-wave design with low group velocity (< 4% c) and a 150 degree phase advance per cell. It has an average iris size that produces an acceptable short-range wakefield in the linacs, and dipole mode damping and detuning that adequately suppresses the long-range wakefield. More than eight such structures have operated over 1000 hours at a 60 Hz pulse rate at the design gradient (65 MV/m) and pulse length (400 ns), and have reached breakdown rate levels below the limit for the linear collider. Moreover, the structures are robust in that the breakdown rates continue to decrease over time, and if the structures are briefly exposed to air, the rates recover to their low values within a few days. This paper presents a final summary of the results from this program, which effectively ended last August with the selection of ‘cold’ technology for a next generation linear collider.

ROAC008 Atom Probe Tomography Studies of RF Materials ion, superconducting-RF, vacuum, instrumentation 612
  • J. Norem
    ANL, Argonne, Illinois
  • P. Bauer
    Fermilab, Batavia, Illinois
  • J. Sebastian, D.N. Seidman
    NU, Evanston
  Funding: DOE

We are constructing a facility which combines an atom probe field ion microscope with a multi-element, in-situ deposition and surface modification capability. This system is dedicated to rf studies and the initial goal will be to understand the properties of evaporative coatings: field emission, bonding interdiffusion etc, to suppress breakdown and dark currents in normal cavities. We also hope to use this system to look more generally at interactions of surface structure and high rf fields. We will present preliminary data on structures relevant to normal and superconducting rf systems.

RPAE060 Simulation and Automation of the EEBI Test at ALS simulation, vacuum, monitoring, synchrotron 3485
  • H. Nishimura, W.E. Byrne
    LBNL, Berkeley, California
  Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.

The Errant Electron Beam Interlock (EEBI) is a system that protects the vacuum chamber of the Advanced Light Source (ALS) from synchrotron light damage should the orbit, through a superconducting bend magnet (superbend), become distorted. The EEBI system monitors the vertical beam position on two BPMs, one upstream and the other downstream, of the superbend and dumps the stored beam if the orbit exceeds preset limits in either offset or angle. Discussed are the modeling studies carried out to determine how to create a large vertical bump, both for performing the test and implementing the automated test software.

RPAP013 Characteristic Experimentations of Degrader and Scatterer at MC-50 Cyclotron proton, cyclotron, simulation, monitoring 1356
  • S.-K. Lee, B.H. Choi, K. R. Kim, LHR. Lee, B.-S. Park
    KAERI, Daejon
  Funding: This work is a part of the "Proton Engineering Frontier Project" which is sponsored by the Ministry of Science and Technology of Korea under "21C Frontier R&D Program."

Building proton beam user facilities, especially deciding beam energy level, depends on the attached proton accelerator and users' needs. To adjust beam energy level, two methods are generally used. One is to directly adjust the beam in the accelerator. The other is to adjust beam energy after extracting from the accelerator. Degrader/Scatterer System has been installed in the MC-50 Cyclotron to adjust energy level of the beam used for various application fields. Its degrader and scatterer are made of Al foils and Au foils, respectively. Al thickness are 2, 1, 0.5, 0.3, 0.2, 0.1, 0.05, 0.03, 0.02, 0.01mm and Au thickness are 0.2, 0.1, 0.05, 0.03, 0.02, 0.01mm, respectively. In this study, suitable beam condition was adjusted through overlapping Al/Au foils of various thickness through simulation results. After that, LET(Linear Energy Transfer) value was indirectly acquired by measuring the bragg peak of the external beam through PMMA plastic Phantom and profile was measured by film dosimetry.

RPAP014 Uniform Irradiation Systems Using a Rotatable Stage for Test Facilities of PEFP proton, simulation, dipole, cyclotron 1383
  • B.-S. Park, B.H. Choi, K. R. Kim, S.-K. Lee
    KAERI, Daejon
  Funding: This work is a part of the "Proton Engineering Frontier Project" which is sponsored by the Ministry of Science and Technology of Korea under '21C Frontier R&D Program."

A new irradiation facility has been developed using not only electric magnets but also a rotatable stage. Generally, the scanning method using magnet has been widely used in most of facilities. However, in this study another new methods have been developed: Three scanning method using rotatable stage have been proved to make uniform irradiation-as large as 20 cm in diameter with more than 90% uniformity. The mechanical wobbler system makes the same effect as the wobbler system. And the beam is swept along the spiral path with a fixed and variable angular frequency during the scanning in two spiral scanning systems, respectively.

RPAP022 A Study of Storage Ring Requirements for an Explosive Detection System Using NRA Method proton, storage-ring, emittance, lattice 1790
  • T.-S. F. Wang, J. T. Kwan
    LANL, Los Alamos, New Mexico
  Funding: US Department of Energy

The technical feasibility of an explosives detection system based on the nuclear resonance absorption (NRA) of gamma rays in nitrogen-rich materials was demonstrated at Los Alamos National Laboratory (LANL) in 1993 by using an RFQ proton accelerator and a tomographic imaging prototype.* The study is being continued recently to examine deployment of such an active interrogation system in realistic scenarios. The approach is to use a cyclotron and electron-cooling-equipped storage rings(s) to provide the high quality and high current proton beam needed in a practical application. In this work, we investigate the storage ring requirements for a variant of the airport luggage inspection system considered in the earlier LANL experiments. Estimations are carried out based on the required inspection throughput, the gamma ray yield, the proton beam emittance growth due to scattering with the photon-production target, beam current limit in the storage ring, and the electron cooling rate. Studies using scaling and reasonable parameter values indicate that it is possible to use no more than a few storage rings in a practical NRA luggage inspection system.

*R. E. Morgado et al., SPIE Conf. Proc. 2092, International Society for Optical Engineering, Bellingham, WA, 1993, p. 503.

RPAP023 RF-Based Accelerators for HEDP Research ion, linac, extraction, focusing 1829
  • J.W.  Staples, R. Keller, A. Sessler
    LBNL, Berkeley, California
  • W. Chou
    Fermilab, Batavia, Illinois
  • P.N. Ostroumov
    ANL, Argonne, Illinois
  Funding: This work sponsored by the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.

Accelerator-driven High-Energy Density Physics experiments require typically 1 nanosecond, 1 microcoulomb pulses of mass 20 ions accelerated to several MeV to produce eV-level excitations in thin targets, the "warm dense matter" regime. Traditionally the province of induction linacs, RF-based acceleration may be a viable alternative with recent breakthroughs in accelerating structures and high-field superconducting solenoids. A reference design for an RF-based accelerator for HEDP research is presented using 15 T solenoids and multiple-gap RF structures configured with either multiple parallel beams (combined at the target) or a single beam and a small stacking ring that accumulates 1 microcoulomb of charge. In either case, the beam is ballistically compressed with an induction linac core providing the necessary energy sweep and injected into a plasma-neutralized drift compression channel resulting in a 1 mm radius beam spot 1 nanosecond long at a thin foil or low-density target.

RPAP034 Use Recirculator "SALO" in the Mode of the Neutron Source electron, alignment, injection, emittance 2354
  • I.S. Guk, A. Dovbnya, S.G. Kononenko, F.A. Peev, A.S. Tarasenko
    NSC/KIPT, Kharkov
  • J.I.M. Botman, M.J. Van der Wiel
    TUE, Eindhoven
  The opportunity of use developed in NSC KIPT recirculator SALO* with superconducting accelerating structure TESLA for reception of intensive neutron streams surveyed. As an injector it is supposed to use RF-gun with superconducting accelerating structure. An electron beam with the peak energy 130 ??? is transported on a target located apart of 100 m from recirculator. System of the focusing are designed allowing to gain on a target the required density of a beam. Tolerances on precision of an alignment of magnetooptical devices are calculated.

*I. S. Guk, A. N. Dovbnya, S. G. Kononenko, A. S. Tarasenko, M. van der Wiel, J. I. M. Botman, NSC KIPT Accelerator on Nuclear and High Energy Physics, Proceedings of EPAC 2004, Lucerne, Switzerland, p.761-764.

RPAP035 Photonuclear and Radiation Effects Testing with a Refurbished 20 MeV Medical Electron Linac linac, radiation, electron, photon 2363
  • T. Webb, L.C. DeVeaux, F. Harmon, J.E. Petrisko, R.J. Spaulding
    IAC, Pocatello
  • R. Assink
    Sandia National Laboratories, Albuquerque, New Mexico
  • W. Beezhold
    ISU, Pocatello, Idaho
  An S-band 20 MeV electron linear accelerator formerly used for medical applications has been recommissioned to provide a wide range of photonuclear activation studies as well as various radiation effects on biological and microelectronic systems. Four radiation effect applications involving the electron/photon beams are described. Photonuclear activation of a stable isotope of oxygen provides an active means of characterizing polymer degradation. Biological irradiations of microorganisms including bacteria were used to study total dose and dose rate effects on survivability and the adaptation of these organisms to repeated exposures. Microelectronic devices including bipolar junction transistors (BJTs) and diodes were irradiated to study photocurrent from these devices as a function of peak dose rate with comparisons to computer modeling results. In addition, the 20 MeV linac may easily be converted to a medium energy neutron source which has been used to study neutron damage effects on transistors.  
RPAP036 A Compact 5 MeV S-Band Electron Linac Based X-Ray Source for Industrial Radiography linac, electron, collimation, insertion 2428
  • L. Auditore, R.C. Barnà, D. De Pasquale, U. Emanuele, A. Trifirò, M. Trimarchi
    INFN & Messina University, S. Agata, Messina
  • A. Italiano
    INFN - Gruppo Messina, S. Agata, Messina
  A compact and reliable X-ray source, based on a 5 MeV, 1 kW, S-band electron linac, has been set up at the Dipartimento di Fisica, Universit\‘a di Messina. This source, coupled with a GOS scintillator screen and a CCD camera, represents an innovative transportable system for industrial radiography and X-ray tomography. Optimization of the parameters influencing the e-gamma conversion and the X-ray beam characteristics have been studied by means of the MCNP-4C2 code. The converter choice is the result of the study of the e-gamma conversion performances for different materials and materials thicknesses. Also the converter position with respect to the linac exit window was studied. The chosen converter consists in a Ta-Cu target inserted close to the linac window. The Cu layer acts as a filter both on the electrons from the source and on the low energy X-rays. The X-ray beam angular profile was studied by means of GafChromic films with and without collimation. In the final source project, a collimation system provides a 14 cm diameter X-ray spot at the sample position and first radiographyc results were obtained by inspecting different density materials and thicknesses.  
RPAP039 Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter ion, emittance, plasma, chromatic-effects 2568
  • J.J. Barnard, D. A. Callahan, A. Friedman, R.W. Lee, M. Tabak
    LLNL, Livermore, California
  • R.J. Briggs
    SAIC, Alamo, California
  • R.C. Davidson, L. Grisham
    PPPL, Princeton, New Jersey
  • E. P. Lee, B. G. Logan, P. Santhanam, A. Sessler, J.W.  Staples, J.S. Wurtele, S. Yu
    LBNL, Berkeley, California
  • C. L. Olson
    Sandia National Laboratories, Albuquerque, New Mexico
  • D. Rose, D.R. Welch
    ATK-MR, Albuquerque, New Mexico
  Funding: Work performed under the auspices of the U.S. Department of Energy under University of California contract W-7405-ENG-48 at LLNL, University of California contract DE-AC03-76SF00098 at LBNL, and contract DEFG0295ER40919 at PPPL.

One approach to heat a target to "Warm Dense Matter" conditions (similar, for example, to the interiors of giant planets or certain stages in Inertial Confinement Fusion targets), is to use intense ion beams as the heating source. By consideration of ion beam phase space constraints, both at the injector, and at the final focus, and consideration of simple equations of state, approximate conditions at a target foil may be calculated. Thus target temperature and pressure may be calculated as a function of ion mass, ion energy, pulse duration, velocity tilt, and other accelerator parameters. We examine the variation in target performance as a function of various beam and accelerator parameters, in the context of several different accelerator concepts, recently proposed for WDM studies.

RPAP048 SNS Diagnostics Timing Integration SNS, diagnostics, controls, Spallation-Neutron-Source 3001
  • C.D. Long
    Innovative Design, Knoxville, Tennessee
  • W. Blokland, D.J. Murphy, J. Pogge, J.D. Purcell
    ORNL, Oak Ridge, Tennessee
  • M. Sundaram
    University of Tennessee, Knoxville, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

The Spallation Neutron Source (SNS) accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is PC-based running Windows XP Embedded for its OS and LabVIEW as its programming language. Coordinating timing among the various diagnostics instruments with the generation of the beam pulse is a challenging task that we have chosen to divide into three phases. First, timing was derived from VME based systems. In the second phase, described in this paper, timing pulses are generated by an in house designed PCI timing card installed in ten diagnostics PCs. Using fan-out modules, enough triggers were generated for all instruments. This paper describes how the Timing NAD (Network Attached Device) was rapidly developed using our NAD template, LabVIEW’s PCI driver wizard, and LabVIEW Channel Access library. The NAD was successfully commissioned and has reliably provided triggers to the instruments. This work supports the coming third phase where every NAD will have its own timing card.

RPAT005 Beam Diagnostics for the J-PARC Main Ring Synchrotron beam-losses, proton, electron, pick-up 958
  • T. Toyama, D.A. Arakawa, Y. Hashimoto, S. Lee, T. Miura, S. Muto
    KEK, Ibaraki
  • N. Hayashi, J. Kishiro, R. Toyokawa
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  Beam diagnostics: beam intensity monitors (DCCT, SCT, FCT, WCM), beam position monitors (ESM), beam loss monitors (proportional chamber, air ion chamber), beam profile monitors (secondary electron emission, gas-sheet) have been designed, tested, and will be installed for the Main Ring synchrotron of J-PARC (Japan Proton Accelerator Research Complex). This paper describes the basic design principle and specification of each monitor, with a stress on how to cope with high power beam (average circulation current of ~12 A) and low beam loss operation (less than 1 W/m except a collimator region). Some results of preliminary performance test using present beams and a radiation source will be reported.  
RPAT022 Optical Faraday Cup for Heavy Ion Beams ion, heavy-ion, diagnostics, radiation 1805
  • F.M. Bieniosek, S. Eylon, P.K. Roy, S. Yu
    LBNL, Berkeley, California
  Funding: Work performed under the auspices of the U.S. Department of Energy by the university of California, Lawrence Berkeley National Laboratory under Contract No. DE-AC03-76F00098.

We have been using alumina scintillators for imaging beams in heavy-ion beam fusion experiments in 2 to 4 transverse dimensions.* The scintillator has limitations on lifetime, linearity, and time response. As a possible replacement for the scintillator, we are studying the technique of imaging the beam on a gas cloud. A gas cloud for imaging the beam may be created on a solid hole plate placed in the path of the beam, or by a localized gas puff. It is possible to image the beam using certain fast-quenching optical spectral lines that closely follow beam current density and are independent of gas density. We describe this technique and show experimental data using a nitrogen line at 394.1 nm. This approach has promise to be a new fast beam current diagnostic on a nanosecond time scale.

*FM Bieniosek, L Prost, W Ghiorso, Beam imaging diagnostics for heavy ion beam fusion experiments, Paper WPPB050, PAC 2003.

RPAT035 Development of an Optical Transition Radiation Detector for Profile Monitoring of Antiproton and Proton Beams at FNAL proton, antiproton, radiation, injection 2381
  • V.E. Scarpine, C.W. Lindenmeyer, G. R. Tassotto
    Fermilab, Batavia, Illinois
  • A.H. Lumpkin
    ANL, Argonne, Illinois
  Funding: Work Supported by the U.S. Department of Energy under Contract No. DE-AC02-CH03000 and by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38.

Optical transition radiation (OTR) detectors are being developed at Fermi National Acceleratory Laboratory (FNAL) as part of the collider Run II upgrade program and as part of the NuMI primary beamline. These detectors are designed to measure 150 GeV antiprotons as well as 120 GeV proton beams over a large range of intensities. Design and development of an OTR detector capable of measuring beam in both directions down to beam intensities of ~5·109 particles for nominal beam sizes is presented. Applications of these OTR detectors as an on-line emittance monitor for both antiproton transfers and reverse-injected protons, as a Tevatron injection profile monitor, and as a high-intensity beam profile monitor for NuMI are discussed. In addition, different types of OTR foils are being evaluated for operation over the intensity range of ~5·109 to over 1·1013 particles per pulse and these are described.

RPAT044 Segmented Foil SEM Grids at Fermilab beam-losses, booster, proton, instrumentation 2821
  • S.E. Kopp, D. Indurthy, Z. Pavlovich, M. Proga, R.M. Zwaska
    The University of Texas at Austin, Austin, Texas
  • B.B. Baller, S.C. Childress, R. Ford, D. Harris, C.L.K. Kendziora, C.D. Moore, G. R. Tassotto
    Fermilab, Batavia, Illinois
  Segmented Secondary Emission Monitors (SEM's) will be used to monitor the extracted 120 GeV proton beam for the NuMI facility at Fermilab. The SEM's are constructed from 5 micrometer thick Ti foils. The chambers have 10 cm beam aperture, and the foils are designed to result in 4·10-6 fractional beam loss when inserted in the beam. The foil strips have dynamic tensioning to withstand the heating from the 400kW proton beam. Results from prototype beam tests as well as from commissioning in the NuMI line will be presented.  
RPAT070 Mechanical and Thermal Design of the CEBAF Hall A Beam Calorimeter radiation, vacuum, electron, simulation 3819
  • M.E. Bevins, A.R. Day, P. Degtiarenko, L.A. Dillon-Townes, A. Freyberger, R. Gilman, A. Saha, S. Slachtouski
    Jefferson Lab, Newport News, Virginia
  Funding: DOE.

A calorimeter has been proposed to provide 0.5% - 1.0% absolute measurements of beam current in the Hall A end station of the Thomas Jefferson National Accelerator Facility (JLab) CEBAF machine. Silver and copper calorimeters built in the 1960’s achieved precisions of about 1%. Modern powder metallurgy processes have produced high density, high thermal conductivity tungsten-copper composite materials that will minimize beam loss while maintaining a rapid thermal response time. Heat leaks will be minimized by mounting the mass in vacuum on glass ceramic mounts. A conduction cooling scheme utilizes an advanced carbon fiber compliant thermal interface material. Transient finite difference and finite element models were developed to estimate heat leaks and thermal response times.

RPAT077 Beam Test Proposal of an ODR Beam Size Monitor at the SLAC FFTB radiation, photon, optics, monitoring 4015
  • Y. Fukui, D. Cline, F. Zhou
    UCLA, Los Angeles, California
  • A. Aryshev, V. Karataev, T. Muto, M. Tobiyama, J.U. Urakawa
    KEK, Ibaraki
  • P.R. Bolton, M.C. Ross
    SLAC, Menlo Park, California
  • R. Hamatsu
    TMU, Hatioji-shi,Tokyo
  • G.A. Naumenko, A. Potylitsyn, A. Sharafutdinov
    Tomsk Polytechnic University, Physical-Technical Department, Tomsk
  We design a single bunch transverse beam size monitor which will be tested to measure the 29 GeV electron/positron beam at the SLAC FFTB beam line.The beam size monitor uses a CCD camera to make images of the interference pattern of the optical diffraction radiation from conductive slit target which are placed close to the beam path. In this method, destruction of the accelerated electron/positron beam bunches due to the beam size monitoring is negligible, which is vital to the operation of the Linear Collider project. A dis-phased conductive slit target and a lens system allow us to recover the sensitivity of the transverse beam size with a small photon yield ratio at the valley to that at the peak due to the large gamma*λ, and with the near field effect due to the large λ*gamma**2. A solution for non-negligible divergence at the SLAC FFTB is also discussed.  
RPAT079 Resolution of Transverse Electron Beam Measurements Using Optical Transition Radiation radiation, electron, plasma, acceleration 4042
  • R. Ischebeck, F.-J. Decker, M.J. Hogan, R.H. Iverson, P. Krejcik, R. Siemann, D.R. Walz
    SLAC, Menlo Park, California
  • C.E. Clayton, C. Huang, W. Lu
    UCLA, Los Angeles, California
  • S. Deng, E. Oz
    USC, Los Angeles, California
  • M. Lincoln
    Stanford University, Stanford, Califormia
  Funding: Work supported by Department of Energy contracts DE-AC02-76SF00515 (SLAC), DE-FG03-92ER40745, DE-FG03-98DP00211, DE-FG03-92ER40727, DE-AC-0376SF0098, and National Science Foundation grants No. ECS-9632735, DMS-9722121 and PHY-0078715.

In the plasma wakefield acceleration experiment E-167, optical transition radiation is used to measure the transverse profile of the electron bunches before and after the plasma acceleration. The distribution of the electric field from a single electron does not give a point-like distribution on the detector, but has a certain extension. Additionally, the resolution of the imaging system is affected by aberrations. The transverse profile of the bunch is thus convolved with a point spread function (PSF). Algorithms that deconvolve the image can help to improve the resolution. Imaged test patterns are used to determine the modulation transfer function of the lens. From this, the PSF can be reconstructed. The Lucy-Richardson algorithm is used to deconvolute this PSF from test images.

RPAT088 Energy-Spread-Feedback System for the KEKB Injector Linac feedback, linac, electron, positron 4212
  • M. Satoh, K.  Furukawa, T. Suwada
    KEK, Ibaraki
  New energy-spread feedback system using nondestructive energy-spread monitors have been developed in order to control and stabilize the energy spreads of single-bunch electron and positron beams in the KEKB injector linac. The well-controlled feedback systems of the injector linac are successfully working in dairy operation not only for keeping the injection rate higher along with the beam-orbit and energy feedback systems but also for reducing a background level to the high-energy B-factory experiment. The energy spreads of the injection beams are well stabilized within 0.2%, 0.5% and 0.3% for the electron beam, the positron beam, and the high-current primary electron beam for positron production, respectively, through the energy-spread feedback system under the nominal operation condition. In this paper, we will report in detail the energy-spread feedback system using the nondestructive energy-spread monitors with multi-strip-line electrodes and their performance in the KEKB operation.  
RPAT095 Time Resolved X-Ray Spot Size Diagnostic diagnostics, alignment, electron, shielding 4302
  • R.A. Richardson, F.W. Chambers, S. Falabella, G. Guethlein, B.A. Raymond, J.T. Weir
    LLNL, Livermore, California
  Funding: This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.

A diagnostic was developed for the determination of temporal history of an X-ray spot. A pair of thin (0.5 mm) slits image the x-ray spot to a fast scintillator which is coupled to a fast detector, thus sampling a slice of the X-Ray spot. Two other scintillator/detectors are used to determine the position of the spot and total forward dose. The slit signal is normalized to the dose and the resulting signal is analyzed to get the spot size. The position information is used to compensate for small changes due to spot motion and misalignment. The time resolution of the diagnostic is about 1 ns and measures spots from 0.5 mm to over 3 mm. The theory and equations used to calculate spot size and position are presented, as well as data. The calculations assume a symmetric, Gaussian spot. The spot data is generated by the ETA II accelerator, a 2kA, 5.5 MeV, 60ns electron beam focused on a Tantalum target. The spot generated is typically about 1 mm FWHM. Comparisons are made to an X-ray pinhole camera which images the XRay spot (in 2D) at four time slices.

RPAT100 Radiation-Hard Beam Position Detector for Use in the Accelerator Dump Lines electron, radiation, monitoring, radio-frequency 4341
  • P. Degtiarenko, D.W. Dotson, V.P. Popov
    Jefferson Lab, Newport News, Virginia
  Funding: This work supported by the U.S. Department of Energy under contract DE-AC05-84ER40150

The new proposed method of beam position measurement is particularly suitable for monitoring high energy, and high power accelerated beams of charged particles in the vicinity of power beam dumps. Generally, the beam quality in those areas is very poor, and any equipment positioned there must be extremely resistant to radiation damage. We have found that a plate made of Chemical Vapor Deposition (CVD) Silicon Carbide (SiC) has a set of physical properties that make it suitable for such an application. CVD SiC material is a chemically inert, extremely radiation-hard, thermo-resistive semiconductor capable of withstanding working temperatures up to 2000 degrees Kelvin. It has good thermal conductivity comparable to that of Aluminum, which makes it possible to use it in high-current particle beams. High electrical resistivity of the material, and its semiconductor properties allow characterization of the position of a particle beam crossing such a plate by measuring balance of electrical currents at the plate ends. The design of a test device, and first results are presented in the report.

ROAB003 Highly Compressed Ion Beams for High Energy Density Science ion, plasma, heavy-ion, acceleration 339
  • A. Friedman, J.J. Barnard, D. A. Callahan, G.J. Caporaso, D.P. Grote, R.W. Lee, S.D. Nelson, M. Tabak
    LLNL, Livermore, California
  • R.J. Briggs
    SAIC, Alamo, California
  • C.M. Celata, A. Faltens, E. Henestroza, E. P. Lee, M. Leitner, B. G. Logan, G. Penn, L. R. Reginato, A. Sessler, J.W.  Staples, W. Waldron, J.S. Wurtele, S. Yu
    LBNL, Berkeley, California
  • R.C. Davidson, L. Grisham, I. Kaganovich
    PPPL, Princeton, New Jersey
  • C. L. Olson, T. Renk
    Sandia National Laboratories, Albuquerque, New Mexico
  • D. Rose, C.H. Thoma, D.R. Welch
    ATK-MR, Albuquerque, New Mexico
  Funding: Work performed under auspices of USDOE by U. of CA LLNL & LBNL, PPPL, and SNL, under Contract Nos. W-7405-Eng-48, DE-AC03-76SF00098, DE-AC02-76CH03073, and DE-AC04-94AL85000, and by MRC and SAIC.

The Heavy Ion Fusion Virtual National Laboratory (HIF-VNL) is developing the intense ion beams needed to drive matter to the High Energy Density (HED) regimes required for Inertial Fusion Energy (IFE) and other applications. An interim goal is a facility for Warm Dense Matter (WDM) studies, wherein a target is heated volumetrically without being shocked, so that well-defined states of matter at 1 to 10 eV are generated within a diagnosable region. In the approach we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto thin target "foils," which may in fact be foams or "steel wool" with mean densities 1% to 100% of solid. This approach complements that being pursued at GSI, wherein high-energy ion beams deposit a small fraction of their energy in a cylindrical target. We present the requirements for warm dense matter experiments, and describe suitable accelerator concepts, including novel broadband traveling wave pulse-line, drift-tube linac, RF, and single-gap approaches. We show how neutralized drift compression and final focus optics tolerant of large velocity spread can generate the necessarily compact focal spots in space and time.

ROAB004 Ion Effects in the DARHT-II Downstream Transport ion, septum, simulation, ion-effects 375
  • K.-C.D. Chan, H. Davis, C. Ekdahl
    LANL, Los Alamos, New Mexico
  • T.C. Genoni, T.P. Hughes
    ATK-MR, Albuquerque, New Mexico
  • M.E. Schulze
    GA, San Diego, California
  Funding: Work supported by US NNSA/DOE.

The DARHT-II accelerator produces an 18-MeV, 2-kA, 2-μs electron beam pulse. After the accelerator, the pulse is delivered to the final focus on an x-ray producing target via a beam transport section called the Downstream Transport. Ions produced due to beam ionization of residual gases in the Downstream Transport can affect the beam dynamics. Ions generated by the head of the pulse will cause modification of space-charge forces at the tail of the pulse so that the beam head and tail will have different beam envelopes. They may also induce ion-hose instability at the tail of the pulse. If these effects are significant, the focusing requirements of beam head and tail at the final focus will become very different. The focusing of the complete beam pulse will be time dependent and difficult to achieve, leading to less efficient x-ray production. In this paper, we will describe the results of our calculations of these ion effects at different residual-gas pressure levels. Our goal is to determine the maximum residual-gas pressure allowable in DARHT-II Downstream Transport such that the required final beam focus is achievable over the entire beam pulse under these deleterious ion effects.

ROAD002 Remote Handling in High-Power Proton Facilities SNS, proton, vacuum, shielding 174
  • G.R. Murdoch
    ORNL, Oak Ridge, Tennessee
  Design for remote handling of highly activated accelerator components is becoming more prevalent as proton facilities are designed and constructed to provide ever-increasing beam powers. During operation of these facilities it is expected that many components will become activated, consequently mechanical engineering design work must address this issue if components are to be maintained by traditional hands-on methods. These design issues are not new and operating proton facilities around the world have gone through the same process to varying degrees. In this paper we discuss the design and design philosophy of remote handling of active accelerator components, using as examples designs which have been proven at operating facilities, as well as new approaches which are being incorporated into accelerator facilities under construction, such as the Spallation Neutron Source and J-PARC.

SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

ROAD003 Post-Irradiation Properties of Candidate Materials for High-Power Targets proton, radiation, linac, booster 333
  • H.G. Kirk, H. Ludewig, L.F. Mausner, N. Simos, P. Thieberger
    BNL, Upton, Long Island, New York
  • Y. Hayato, K. Yoshimura
    KEK, Ibaraki
  • K.T. McDonald
    PU, Princeton, New Jersey
  • J. Sheppard
    SLAC, Menlo Park, California
  • L.P. Trung
    Stony Brook University, Stony Brook
  Funding: U.S. DOE.

The long term survivability of materials which can be used either for high-intensity targets or for the environment surrounding the target can be greatly influenced by how the physical properties of the material are altered by radiation damage. We have irradiated several candidate materials and report here on physical properties before and after irradiation.

RPPE018 Material Damage Test with 450 GeV LHC-Type Beam simulation, proton, hadron, injection 1607
  • V. Kain, J. Ramillon, R. Schmidt, K.V. Vorderwinkler, J. Wenninger
    CERN, Geneva
  The design of LHC protection elements is based on assumptions on damage levels, which are derived from simulations. A dedicated experiment was prepared and carried out to cross-check the validity of this approach by trying to damage material in a controlled way with beam. The impact of a 450 GeV beam extracted from the SPS on a specially designed high-Z target with a simple geometry, comprising several typical materials used for LHC equipment, was simulated. The beam intensities for the test were chosen to exceed the damage limits of parts of the target. Results of the simulations are presented and compared with test results.  
RPPE026 Operating Experience with Meson Production Targets at TRIUMF proton, radiation, alignment, beam-losses 1919
  • E.W. Blackmore, A.S. Dowling, R. Ruegg, M.C. Stenning
    TRIUMF, Vancouver
  High power targets are now required for operation at beam powers in excess of 1 MW for spallation neutron sources and neutrino factories. TRIUMF has been operating beryllium and graphite meson production targets for many years. Although the proton beam power of 100 kW at 500 MeV is lower, the beam densities and fluences are higher than most operating solid targets as other accelerators use rotating targets or larger beam spots. The beam size on the TRIUMF targets is maintained at 0.15 cm2 and this beam density leads to proton fluences of 1·1023 protons/cm2 per year. The beryllium targets are rectangular rods immersed in a water-cooled stainless steel jacket. The pyrolytic graphite targets consist of pie-shaped segments bonded to a water-cooled copper saddle. Operating experience shows that the graphite targets suffer thermal damage above beam currents of 120 uA but will operate for long periods at 100 uA. The beryllium targets can operate to 200 uA and appear to survive radiation damage beyond 10 dpa although some targets have failed due to structural damage. This paper will describe the operating experience with these targets and present some thermal and radiation calculations.  
RPPE027 High Intensity High Energy E-Beam Interacting with a Thin Solid State Target: First Results at AIRIX electron, focusing, scattering, emittance 1982
  • M. Caron, F. Cartier, D.C. Collignon, L.H. Hourdin, E. Merle, M. Mouillet, C. Noel, D.P. Paradis, O.P. Pierret
    CEA, Pontfaverger-Moronvilliers
  • O. Mouton, N. Pichoff
    CEA/DAM, Bruyères-le-Châtel
  Funding: CEA, Polygone d’Expérimentation de Morronvilliers, LEXA F-51 475 Pontfaverger (France).

AIRIX is a 2 kA, 20 MeV, 60 ns linear accelerator dedicated to X-ray flash radiography. During a regular running phase, the primary electron beam is accelerated to and focused on a high atomic number target in order to generate X-rays by brembtrahlung mainly. The huge energy density deposited into the material is such that temperature rises up to 15000°K and that clusters and particles are violently ejected from the surface. In that mechanism, the backward emission speed can reach 5 km.s-1 and the debris can gradually accumulate and subsequently contaminate some sensitive parts of the machine. In order to protect the whole accelerating line from the detrimental effect of back-ejected particles, we have investigated the technical feasibility of a thin foil implementation upstream the X-ray converter.

RPPE029 Rotating Aperture Deuterium Gas Cell Development for High Brightness Neutron Production linac, vacuum, beam-transport, optics 2074
  • B. Rusnak, M. Hall, S. Shen
    LLNL, Livermore, California
  Funding: This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.

A project is underway at LLNL to design and build a system for fast neutron imaging. The approach being pursued will use a 7 MeV deuterium linac for producing high-energy neutrons via a D(d,n)3He reaction. To achieve a high-brightness neutron source, a windowless rotating aperture gas cell approach is being employed. Using a series of close-tolerance rotor and stator plates, a differential pumping assembly has been designed and built that contains up to 3 atmospheres of deuterium gas in a 40 mm long gas cell. Rarefaction of the gas due to beam-induced heating will be addressed by rapidly moving the gas across the beam channel in a crossflow tube. The design and fabrication process has been guided by extensive 3D modeling of the hydrodynamic gas flow and structural dynamics of the assembly. Summaries of the modeling results, the fabrication and assembly process for the rotating aperture system, and initial measurements of gas leakage shall be presented.

RPPE031 Target and Horn Cooling for the Very Long Baseline Neutrino Experiment proton, radiation, focusing, simulation 2209
  • S. Bellavia, S.A. Kahn, H.G. Kirk, H. Ludewig, D. Raparia, N. Simos
    BNL, Upton, Long Island, New York
  Funding: This work is performed under the auspices of the US DOE.

Thermodynamic studies have been performed for the beam target and focusing horn system to be used in a very long baseline neutrino oscillation experiment. A 2mm rms beam spot with power deposition of over 18 KW presents challenging material and engineering solutions to this project. Given that the amount of heat transferred by radiation alone from the target to the horn is quite small, the primary mechanism is heat removal by forced convection in the annular space between the target and the horn. The key elements are the operating temperature of the target, the temperature of the cooling fluid and the heat generation rate in the volume of the target that needs to be removed. These working parameters establish the mass flow rate and velocity of the coolant necessary to remove the generated heat. Several cooling options were explored using a carbon-carbon target and aluminum horn. Detailed analysis, trade studies and simulations were performed for cooling the horn and target with gaseous helium as well as water.

RPPE033 Engineering the SNS RTBT/Target Interface for Remote Handling vacuum, SNS, shielding, proton 2278
  • M. Holding, C.M. Hammons, B.R. Lang, G.R. Murdoch, K.G. Potter, R.T. Roseberry
    ORNL, Oak Ridge, Tennessee
  The SNS facility is designed for a 1.4MW 1.0GeV proton beam and the interface region of this beam with the Hg spallation target will be highly activated. This installation is located about fifteen feet below the access floor and the activity levels in the RTBT/Target interface are sufficiently high to warrant the application of Remote Handling techniques. The installed components are manufactured from radiation hard materials with serviceability beyond the lifetime of the machine, and all connections and mechanisms have been simplified to allow remote handling. The application of pneumatics to facilitate the assembly of major components and to the operation of moveable diagnostics has produced some unique design solutions.  
RPPE034 Measurements of the Energy Deposition Profile for 238U Ions with Energy 500 and 950 MEV/U in Stainless Steel and Copper Targets ion, heavy-ion, energy-calibration, vacuum 2318
  • E. Mustafin, I. Hofmann, D. Schardt, K. Weyrich
    GSI, Darmstadt
  • A. Fertman, A. Golubev, A. Kantsyrev, V. Luckjashin
    ITEP, Moscow
  • A. Gnutov, A. Kunin, Y. Panova, V. Vatulin
    VNIIEF, Sarov (Nizhnii Gorod)
  • L.N. Latysheva, N. Sobolevskiy
    RAS/INR, Moscow
  Funding: Supported by the grant of the GSI-INTAS #03-54-3588.

Sub-millimeter wall thickness is foreseen for the vacuum tubes in the magnets of the superconducting dipoles of the SIS100 and SIS300 of the FAIR Project. The Bragg peak of the energy deposition by the U ions in these walls may lie dangerously close to the superconducting cables. Thus the precise knowledge of the dE/dx profile is essential for estimating the heat load by the lost ions in the vicinity of the superconducting wires. Here we present the results of the measurement of the U ion beam energy deposition profile in Cu and stainless steel targets and compare the measured data with the Monte-Carlo simulation using the SHIELD code.

RPPE045 Vacuum Pumping Performance Comparison of Non-Evaporable Getter Thin Films Deposited Using Argon and Krypton as Sputtering Gases vacuum, cathode, laser, linac 2860
  • X. Liu, Y. He, Y. Li
    Cornell University, Department of Physics, Ithaca, New York
  • M.R. Adams
    Cornell University, Ithaca, New York
  Funding: Work Supported by the National Science Foundation.

Owing to the outstanding vacuum performance and the low secondary electron yield, non-evaporable getter (NEG) thin film deposited onto interior walls has gained widespread acceptance and has been incorporated into many accelerator vacuum system designs. The titanium-zirconium-vanadium (T-Zr-V) NEG thin films were deposited onto the interior wall of stainless steel pipes via DC magnetron sputtering method using either argon or krypton gas as sputtering gas. Vacuum pumping evaluation tests were carried out to compare vacuum pumping performances of the Ti-Zr-V NEG thin films deposited using argon or krypton. The results showed much higher initial pumping speed for the Kr-sputtered NEG film than the Ar-sputtered film, though both films have similar activation behavior. The compositions and textures of both thin films were measured to correlate to the pumping performances.

RPPE046 A Summary and Status of the SNS Ring Vacuum Systems vacuum, injection, quadrupole, dipole 2929
  • M. Mapes, H.-C. Hseuh, J. Rank, L. Smart, R.J. Todd, D. Weiss
    BNL, Upton, Long Island, New York
  • M.P. Hechler, P. Ladd
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

The Spallation Neutron Source (SNS) ring is designed to accumulate high intensity protons. The SNS ring vacuum system consists of the High Energy Beam Transport (HEBT) line, Accumulator Ring and the Ring to Target Beam Transport (RTBT) line. The Accumulator ring has a circumference of 248m with 4 arcs and 4 straight sections, while the RTBT and HEBT have a total length of 350m of beam transport line. Ultrahigh vacuum of 10-9 Torr is required in the accumulator ring to minimize beam-residual gas ionization. To reduce the secondary electron yield (SEY) and the associated electron cloud instability, the ring vacuum chambers are coated with Titanium-Nitride (TiN). This paper describes the design, fabrication, assembly and vacuum processing of the ring and beam transport vacuum systems as well as the associated instrumentation and controls.

RPPE065 Beam Loss Ion Chamber System Upgrade for Experimental Halls ion, radiation, beam-losses, monitoring 3650
  • D.W. Dotson, D.J. Seidman
    Jefferson Lab, Newport News, Virginia
  Funding: Work supported by: U.S. DOE Contract No DE-AC05-84ER4015.

The Beam loss Ion Chamber System (BLICS) was developed to protect Jefferson Labs transport lines, targets and beam dumps from a catastrophic "burn through." Range changes and testing was accomplished manually requiring the experiment to be shut down. The new upgraded system is based around an "off the shelf" Programmable Logic Controller located in a single controll box supporting up to ten individual detectors. All functions that formerly required an entry into the experimental hall and manual adjustment can be accomplished from the Machine Control Center (MCC). A further innovation was the addition of a High Voltage "Brick" at the detector location. A single cable supplies the required voltage for the Brick and a return line for the ion chamber signal. The read back screens display range, trip point, and accumulated dose for each location. The new system is very cost effective and significantly reduces the amount of lost experimental time.

RPPP029 Analysis of Positron Collection in Linear Collider positron, electron, damping, emittance 2101
  • Y.K. Batygin
    SLAC, Menlo Park, California
  Funding: Work is supported by Department of Energy Contract No. DE-AC02-76SF00515

In the Linear Collider, the positron capture system includes a positron production target, a flux concentrator, and a linac to accelerate positrons up to the injection energy of the positron damping ring. Two schemes for positron production have been studied: (i) a conventional approach with an electron beam interacting with a high-Z target and (ii) polarized positron production using polarized photons generated in a helical undulator by electron beam which then interact with a positron production target. Efficiency of positron collector is defined by positron yield which is a ratio of positrons accepted into damping ring to the number of incident electrons or photons. The capture system has been optimized to insure high positron yield into the 6-dimensional acceptance of the damping ring keeping the high value of positron polarization. Various parameters affecting the positron capture are analyzed.

RPPP039 Heat Deposition in Positron Sources for ILC positron, photon, electron, shielding 2574
  • V. Bharadwaj, R. Pitthan, J. Sheppard, H. Vincke, J.W. Wang
    SLAC, Menlo Park, California
  Funding: Work supported by Department of Energy contract DE-AC02-76SF00515.

In an ILC positron source, multi-GeV electrons or multi-MeV photons impinge on a metal target. In either case, the incoming beam power is hundreds of kilowatts. Various computer programs - such as FLUKA or MARS – can calculate how the incoming beam showers in the target and can track the particle showers through the positron source system. The incoming energy ends up as heat in the various positron source elements. This paper presents results from such calculations and their impact on the design of a positron source for the ILC.

RPPT059 Spectrum from the Proposed BNL Very Long Baseline Neutrino Facility proton, alignment, simulation, background 3476
  • S.A. Kahn, M. Diwan
    BNL, Upton, Long Island, New York
  Funding: The work was performed with the support of the U.S. DOE under Contract No. DE-AC02-98CH10886.

This paper calculates the neutrino flux that would be seen at the far detector location from the proposed BNL Very Long Baseline Neutrino Facility. The far detector is assumed to be located at an underground facility in South Dakota 2540 km from BNL. The neutrino beam facility uses a 1 MW upgraded AGS to provide an intense proton beam on the target and a magnetic horn to focus the secondary pion beam. The paper will examine the sensitivity of the neutrino flux at the far detector to the positioning of the horn and target so as to establish alignment tolerances for the neutrino system.

RPPT060 The MuCool Test Area at Fermilab linac, proton, shielding, radiation 3482
  • C. Johnstone, A. Bross, I. Rakhno
    Fermilab, Batavia, Illinois
  Funding: Work supported by the US Dept. of Energy under contract No. DE-AC02-76CH03000

A new experimental area designed to develop, test and verify muon ionization cooling using the 400- MeV Fermilab Linac proton beam began construction in spring, 2002. This area will be used initially for cryogenic tests of liquid-hydrogen absorbers for the MUCOOL R&D program and, later, for high-power beam tests of these absorbers and other prototype muon-cooling apparatus. The experimental scenarios being developed for muon facilities involve collection, capture, and cooling of large-emittance, high-intensity muon beams–~1013 muons at a repetition rate of 15Hz, so that conclusive tests of the apparatus require full Linac beam, or 1.6 x 1013 p at 15 Hz. To support the muon cooling facility, a new primary beamline will divert beam from the Linac to the test facility. Located southwest of Wilson Hall between the Linac berm and parking lot, implementation of the facility and associated beamline takes advantage of civil construction and resources that remain from the 400-MeV Linac Upgrade Project. The design concept for the MuCool facility is taken from an earlier proposal, but modifications to the existing proposal were necessary to accommodate high-intensity beam, cryogenics, and the increased scale of the cooling experiments.

RPPT062 Radiation Simulations for the Proposed ISOL Stations for RIA shielding, radiation, simulation, ion 3561
  • R.M. Ronningen, V. Blideanu, G. Bollen, D. Lawton, P.F. Mantica, D.J. Morrissey, B. Sherrill, A. Zeller
    NSCL, East Lansing, Michigan
  • L. Ahle, J.L. Boles, S. Reyes, W. Stein
    LLNL, Livermore, California
  • J.R. Beene, W. Burgess, H.K. Carter, D.L. Conner, T.A. Gabriel, L.K. Mansur, R. Remec, M.J. Rennich, D.W. Stracener, M. Wendel
    ORNL, Oak Ridge, Tennessee
  • T.A. Bredeweg, F.M. Nortier, D.J. Vieira
    LANL, Los Alamos, New Mexico
  • P. Bricault
    TRIUMF, Vancouver
  • L.H. Heilbronn
    LBNL, Berkeley, California
  Funding: This work is supported in part by Michigan State University, the U.S. Department of Energy, and the National Research Council of Canada.

The Department of Energy's Office of Nuclear Physics, within the Office of Science (SC), has given high priority to consider and analyze design concepts for the target areas for the production of rare isotopes via the ISOL technique at the Rare-Isotope Accelerator (RIA) Facility. Key criteria are the maximum primary beam power of 400 kW, minimizing target change-out time, good radiological protection, flexibility with respect to implementing new target concepts, and the analysis and minimization of hazards associated with the operation of the facility. We will present examples of on-going work on simulations of radiation heating of targets, surrounding components and shielding, component activation, and levels of radiation dose, using the simulation codes MARS, MCNPX, and PHITS. These results are important to make decisions that may have a major impact on the layout, operational efficiency and cost of the facility, hazard analysis, shielding design, civil construction, component design, and material selection, overall layout, and remote handling concepts.

RPPT063 Radiation Simulations and Development of Concepts for High Power Beam Dumps, Catchers and Pre-separator Area Layouts for the Fragment Separators for RIA simulation, radiation, quadrupole, ion 3594
  • R.M. Ronningen, V. Blideanu, G. Bollen, D. Lawton, D.J. Morrissey, B. Sherrill, A. Zeller
    NSCL, East Lansing, Michigan
  • L. Ahle, J.L. Boles, S. Reyes, W. Stein, A. Stoyer
    LLNL, Livermore, California
  • J.R. Beene, W. Burgess, H.K. Carter, D.L. Conner, T.A. Gabriel, L.K. Mansur, R. Remec, M.J. Rennich, D.W. Stracener, M. Wendel
    ORNL, Oak Ridge, Tennessee
  • H. Geissel, H. Iwase
    GSI, Darmstadt
  • I.C. Gomes, F. Levand, Y. Momozaki, J.A. Nolen, B. Reed
    ANL, Argonne, Illinois
  • L.H. Heilbronn
    LBNL, Berkeley, California
  Funding: This work is supported in part by Michigan State University, the US DOE, and the Gesellschaft für Schwerionenforschung, Germany.

The development of high-power beam dumps and catchers, and pre-separator layouts for proposed fragment separators of the Rare-Isotope Accelerator (RIA) facility are important in realizing how to handle the 400 kW in the primary beam. We will present examples of pre-conceptual designs of beam dumps, fragment catchers, and the pre-separator layout. We will also present examples of ongoing work on radiation simulations using the heavy-ion-transport code PHITS, characterizing the secondary radiation produced by the high-power ion beams interacting with these devices. Results on radiation heating of targets, magnet coils, associated hardware and shielding, component activation, and levels of radiation dose will be presented. These initial studies will yield insight into the impact of the high-power dissipation on fragment separator design, remote handling concepts, nuclear safety and potential facility hazard classification, shielding design, civil construction design, component design, and material choices. Furthermore, they will provide guidance on detailed radiation analyses as designs mature.

RPPT064 Holifield Radioactive Ion Beam Facility Development and Status ion, ion-source, extraction, light-ion 3641
  • A. Tatum, J.R. Beene
    ORNL, Oak Ridge, Tennessee
  Funding: Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.

The Holifield Radioactive Ion Beam Facility (HRIBF) is a national user facility dedicated to nuclear structure, reactions, and nuclear astrophysics research with radioactive ion beams (RIBs) using the isotope separator on-line (ISOL) technique. An integrated strategic plan for physics, experimental systems, and RIB production facilities have been developed and implementation of the plan is under way. Specific research objectives are defined for studying the nature of nucleonic matter, the origin of elements, solar physics, and synthesis of heavy elements. Experimental systems upgrade plans include new detector arrays and beam lines, and expansion and upgrade of existing devices. A multifaceted facility expansion plan includes a $4.75M High Power Target Laboratory (HPTL), presently under construction, to provide a facility for testing new target materials, target geometries, ion sources, and beam preparation techniques. Additional planned upgrades include a second RIB production system (IRIS2), an external axial injection system for the present driver cyclotron, ORIC, and an additional driver accelerator for producing high-intensity neutron-rich beams.

RPPT066 Electromigration Issues in High Current Horn electron, secondary-beams, radiation, pulsed-power 3700
  • W. Zhang, S. Bellavia, J. Sandberg, N. Simos, J.E. Tuozzolo, W.-T. Weng
    BNL, Upton, Long Island, New York
  • B. Hseuh
    JHU, Baltimore, Maryland
  Funding: Work performed under the auspices of the U.S. Department of Energy.

The secondary particle focusing horn for the AGS neutrino experiment proposal is a high current and high current density device. The peak current of horn is 300 kA. At the smallest area of horn, the current density is near 8 kA/mm2. At very high current density, a few kA/mm2, the electromigration phenomena will occur. Momentum transfer between electrons and metal atoms at high current density causes electromigration. The reliability and lifetime of focusing horn can be severely reduced by electromigration. In this paper, we discuss issues such as device reliability model, incubation time of electromigration, and lifetime of horn.

RPPT067 A High-Power Target Experiment proton, factory, synchrotron, interaction-region 3745
  • H.G. Kirk, S.A. Kahn, H. Ludewig, R. Palmer, V. Samulyak, N. Simos, T. Tsang
    BNL, Upton, Long Island, New York
  • J.R.J. Bennett
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • T.W. Bradshaw, P. Drumm, T.R. Edgecock, Y. Ivanyushenkov
    CCLRC/RAL, Chilton, Didcot, Oxon
  • I. Efthymiopoulos, A. Fabich, H. Haseroth, F. Haug, J. Lettry
    CERN, Geneva
  • T.A. Gabriel, V.B. Graves, J.R. Haines, P.T. Spampinato
    ORNL, Oak Ridge, Tennessee
  • Y. Hayato, K. Yoshimura
    KEK, Ibaraki
  • K.T. McDonald
    PU, Princeton, New Jersey
  Funding: U.S. Department of Energy.

We describe an experiment designed as a proof-of-principle test for a target system capable of converting a 4 MW proton beam into a high-intensity muon beam suitable for incorporation into either a neutrino factory complex or a muon collider. The target system is based on exposing a free mercury jet to an intense proton beam in the presence of a high strength solenoidal field.

RPPT068 Pion-Muon Concentrating System for Detectors of Highly Enriched Uranium antiproton, simulation, focusing, shielding 3757
  • S.S. Kurennoy, D.B. Barlow, B. Blind, A.J. Jason, N. Neri
    LANL, Los Alamos, New Mexico
  One of many possible applications of low-energy antiprotons collected in a Penning trap can be a portable muon source. Released antiprotons annihilate on impact with normal matter producing on average about 3 charged pions per antiproton, which in turn decay into muons. Existence of such negative-muon sources of sufficient intensity would bring into play, for example, detectors of highly enriched uranium based on muonic X-rays. We explore options of collecting and focusing pions and resulting muons to enhance the muon flux toward the detector. Simulations with MARS and MAFIA are used to choose the target material and parameters of the magnetic system consisting of a few solenoids.  
RPPT069 The Installation Status of the SNS Accumulator Ring SNS, lattice, power-supply, vacuum 3789
  • M.P. Hechler, R.I. Cutler, J.J. Error
    ORNL, Oak Ridge, Tennessee
  • W.J. McGahern
    BNL, Upton, Long Island, New York
  The Spallation Neutron Source (SNS*) SNS accumulator Ring, when completed in 2006, will be capable of delivering a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron production. This paper presents an overview of the issues and logistics associated with the preparation and installation of the accumulator Ring. The preparatory activities which occurred at the Brookhaven National Laboratory, vendors and at the SNS will be discussed as well as the installation sequence and procedures.

SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos and Oak Ridge.

RPPT072 Ion Chamber Arrays for the NuMI Beam at Fermilab hadron, ion, proton, focusing 3892
  • D. Indurthy, R. Keisler, S.E. Kopp, S. Mendoza, Z. Pavlovich, M. Proga, R.M. Zwaska
    The University of Texas at Austin, Austin, Texas
  • M.B. Bishai, M. Diwan, B. Viren
    BNL, Upton, Long Island, New York
  • A.R. Erwin, H.P. Ping, C.V. Velissaris
    UW-Madison/PD, Madison, Wisconsin
  • D. Harris, A. Marchionni, G. Morfin
    Fermilab, Batavia, Illinois
  • J. McDonald, D. Naples, D. Northacker
    University of Pittsburgh, Pittsburgh, Pennsylvania
  The NuMI beamline and the MINOS experiment will study at a long baseline the possible oscillation of muon neutrinos and provide a precision measurement of the oscillation parameters. Neutrinos are produced from charged pion decays, where the pions are produced from interaction of the 120 GeV FNAL Main Injector proton beam with a graphite target. Ion chamber arrays have been built to monitor the resulting muons from pion decays, as well as remnant hadrons at the end of the NuMI decay pipe. The arrays of ion chambers measure both the intensity and lateral profile of the muon and hadron beams, allowing studies of sytematics of the neutrino beam. We will describe the design, construction, and precise calibration of the ion chamber arrays. Initial data from commissioning of the beam line and experience from long-term operations will be presented.  
FOAC002 Status of Neutrino Factory Design and R&D factory, proton, simulation, collider 209
  • D. Li
    LBNL, Berkeley, California
  Funding: Work supported by the US Department of Energy under contract No. DE-AC0376SF00098

Neutrino physics has become increasingly interesting to the high-energy physics community, as it may provide clues to new physics beyond the standard model. The physics potential of a Neutrino Factory–a facility to produce high-energy, high-intensity, high-brightness neutrino beams from decays of muons stored in a muon storage ring–is thus very high. There has been a global R&D effort aimed at a Neutrino Factory design that meets the physics requirements and addresses the key technologies, such as targetry, muon ionization cooling and acceleration. Tremendous progress has been made in the past few years in many aspects of accelerator technology. In this paper, we will review recent worldwide progress toward a cost-effective Neutrino Factory design, with emphasis on the associated R&D programs under the auspices of the U.S. Neutrino Factory and Muon Collider Collaboration.

FOAC004 The Numi Neutrino Beam At Fermilab proton, booster, hadron, antiproton
  • S.E. Kopp
    The University of Texas at Austin, Austin, Texas
  The Neutrinos at the Main Injector (NuMI) is a conventional neutrino beam facility which will use the intense 120 GeV proton beam from the Fermilab Main Injector accelerator. The facility is envisaged to service a variety experiments, in particular the already-constructed MINOS long baseline oscillation experiment, and the proposed NOvA experiment to observe muon neutrino to electron neutrino oscillations. Summarized will be the design of the primary and secondary beam focusing systems, instrumentation to validate the neutrino beam intensity, direction, and energy spectrum, and considerations for coping with the 0.4 MWatt MI beam. The beam line will be commissioned December, 2004, through February, 2005, whereupon operations may begin. Data from the commissioning and experience from first operations will be presented. Further, the suitability of the facility for accepting beam from a proposed 2MW proton driver is discussed.  
FPAE001 Design Work for the High-Energy Storage Ring for Antiprotons of the Future GSI Project antiproton, electron, storage-ring, injection 776
  • A. Lehrach, S. An, K. Bongardt, J. Dietrich, R. Eichhorn, B. Lorentz, R. Maier, S. Martin, D. Prasuhn, Y. Senichev, E.A. Senicheva, H. Stockhorst, R. Tölle, E. Zaplatin
    FZJ, Jülich
  • O. Boine-Frankenheim, A. Dolinskii, M. Steck
    GSI, Darmstadt
  • B. Gålnander, D. Reistad
    TSL, Uppsala
  • F.H. Hinterberger
    Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik,, Bonn
  The High-Energy Storage Ring (HESR) of the future international Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an antiproton cooler and storage ring in the momentum range from 1.5 to 15 GeV/c. The design work for the HESR is organized by a consortium with scientists from FZ Jülich, GSI Darmstadt and TSL Uppsala. An important feature of the new facility is the combination of phase space cooled beams with internal targets, resulting in demanding beam parameter in two operation modes: high luminosity mode with beam intensities up to few times 1011, and high resolution mode with a momentum spread down to 10-5, respectively. To reach these beam parameters very powerful phase space cooling is needed, utilizing high-energy electron cooling and high-bandwidth stochastic cooling. In this paper an overview of the design work is given, focusing on recent developments and planned R&D work.  
FPAE024 Studies Performed in Preparation for the Spallation Neutron Source Accumulator Ring Commissioning injection, beam-losses, proton, multipole 1859
  • S.M. Cousineau, V.V. Danilov, S. Henderson, J.A. Holmes, M.A. Plum
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

The Spallation Neutron Source accumulator ring will compress 1.5?1014, 1 GeV protons from a 1 ms bunch train to a single 695 ns proton bunch for use in neutron spallation. Due to the high beam power, unprecedented control of beam loss will be required in order to control radiation and allow for hands-on maintenance in most areas of the ring. A number of detailed investigations have been performed to understand the primary sources of beam loss and to predict and mitigate problems associated with radiation hot spots in the ring. The ORBIT particle tracking code is used to perform realistic simulations of the beam accumulation in the ring, including detailed modeling of the injection system, transport through the measured magnet fields including higher order multipoles, and beam loss and collimation. In this paper we present the results of a number of studies performed in preparation for the 2006 commissioning of the accumulator ring.

FPAE035 Steps Towards a 3 mA, 1.8 MW Proton Beam at the PSI Cyclotron Facility cyclotron, injection, simulation, space-charge 2405
  • P.A. Schmelzbach, S.R.A. Adam, A. Adelmann, H. Fitze, G. Heidenreich, J.-Y. Raguin, U. Rohrer, P.K. Sigg
    PSI, Villigen
  The PSI Cyclotron Facility produces routinely a 1.8-1.9 mA proton beam at 590 MeV. The beam power reaches 1.1 MW at the the pion production targets and 0.7 MW at the neutron spallation target SINQ. The accelerator complex will be analysed in respect to his potential for future improvements. The ongoing developments aiming to increase the beam intensity to 3 mA and hence the beam power to 1.8 MW will be discussed. Smooth extrapolations of the observed machine parameters as well as recent advances in the theoretical treatment of space charge dominated beams show that this goal can be achieved with available technologies. IA new RF-cavity operated at a voltage in excess of 1 MV has been successfully tested and installed in the Ring Cyclotron. Bunchers for the low energy and the medium energy transfer lines are in the design phase. A conceptual study of new accelerating cavities to replace the obsolete flattop-cavities of the Injector Cyclotron has been performed. While the upgrade of the Ring Cyclotron with four new cavities will be completed in 2008, it is still an open question whether this accelerator will be operated in the "round beam" mode like the Injector Cyclotron or with an upgraded flattopping system.  
FPAE036 Lattice Modification of a 1.2 GeV STB Ring for Generation of High Energy Gamma-Rays Using Internal Target Wire electron, lattice, scattering, simulation 2458
  • F. Hinode, H. Hama, M. Kawai, A. Kurihara, A. Miyamoto, M. Mutoh, M. Nanao, Y. Shibasaki, K. Shinto, S. Takahashi, T. Tanaka
    LNS, Sendai
  A 1.2 GeV Stretcher-Booster Ring (STB ring) has been routinely operated at Laboratory of Nuclear Science (LNS), Tohoku University. The STB ring has functions of a pulse-beam stretcher and a booster-storage ring. In the booster-storage operation, high energy gamma-ray beam generated via bremsstrahlung from internal target wire is utilized for experiments of nuclear physics. Some fractions of circulating electrons are also deflected in the target wire due to Coulomb scattering without significant loss of the energy. The scattered electrons that are not getting out of the dynamic aperture once can circulate in the ring. Such electrons, however, would hit the chamber walls and supports of the target wire during further turns, because they have very large betatron amplitude. Consequently the Coulomb scattered electrons must be a source of significant background and may cause a degradation of gamma-ray beam quality. The quality of the gamma-ray beam has been improved by modifying the lattice functions of the ring, and we report the improvement in this conference.  
FPAE052 The LENS 7 MeV, 10 mA Proton Linac proton, rfq, linac, ion 3200
  • V.P. Derenchuk, D.V. Baxter, A. Bogdanov, W.P. Jones, T. Rinckel, K. A. Solberg
    IUCF, Bloomington, Indiana
  Funding: This work has been supported by the National Science Foundation under grants DMR-0220560, and DMR-0320627, by the Indiana 21st Century Science and Technology Fund, and by the Department of Defense.

The Indiana University Cyclotron Facility (IUCF) has constructed and placed in operation a Low Energy Neutron Source (LENS) using a 10 mA, 7 MeV proton beam incident on a beryllium target. The proton delivery system (PDS) consists of a 25 keV proton injector, an AccSys Technology, Inc. PL7 Linac* and a beam transport line with non-linear beam spreading.** The accelerator and beamline equipment used in this construction are refurbished and upgraded components from the IUCF CIS/Cooler synchrotron*** facility. After commissioning the beam current at 7 MeV will be 10 mA with a pulse width of up to 300 μs and > 1% duty factor. The PDS was constructed and commissioning started in 2004. First operating results will be described.

*D.L. Friesel and W. Hunt, Linac98, pp61-63. **W.P. Jones, et. al., "Non-Linear Beam Transport System for the LENS 7 MeV Proton Beam," this proceedings. ***D.L. Friesel, et. al., EPAC2000, pp. 539-541.

FPAE073 A Free Hg Jet System for Use in a High-Power Target Experiment proton, diagnostics, laser, collider 3895
  • P.T. Spampinato, T.A. Gabriel, V.B. Graves, M.J. Rennich
    ORNL, Oak Ridge, Tennessee
  • A. Fabich, H. Haseroth, J. Lettry
    CERN, Geneva
  • H.G. Kirk, N. Simos, T. Tsang
    BNL, Upton, Long Island, New York
  • K.T. McDonald
    PU, Princeton, New Jersey
  • P. Titus
    MIT/PSFC, Cambridge, Massachusetts
  Funding: Work funded by the U.S. Department Of Energy.

We describe a mercury jet system that is suitable for insertion into the 15cm diameter bore of a high-field solenoid magnet. The device features a hermetically sealed primary containment volume which is enclosed in a secondary containment system to insure isolation of mercury vapors from the remaining experimental environment. The jet diameter is 1-cm while the jet velocity will be up to 20 m/s. Optical diagnostics is incorporated into the target design to allow observation of the dispersal of the mercury as a result of interaction with a 24 GeV proton beam with up to 20 x 1012 ppp.

FPAE074 Beam Parameter Measurement and Control at the SNS Target diagnostics, quadrupole, emittance, SNS 3913
  • M.A. Plum, M. Holding, T. McManamy
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

The spallation neutron production target at the SNS facility is designed for 1.4 MW beam power. Both beam position and profile must be carefully controlled within narrow margins to avoid damage to the target. The position must be within 2 mm of the target center, and 90% of the beam must be within the nominal 70 mm x 200 mm spot size, without exceeding 0.18 A/m2 peak beam current density. This is a challenging problem, since most of the diagnostics are 9 m upstream of the target, and because the high beam power limits the lifetime of intercepting diagnostics. Our design includes a thermocouple halo monitor approximately 2 m upstream of the target face, and a beam position monitor, an insertable harp profile monitor, and a beam shape monitor approximately 9 m upstream. In this paper we will discuss our strategy to commission the beam delivery system and to meet target requirements during nominal operation.

FPAE076 The System of Nanosecond 280-keV-He+ Pulsed Beam ion, ion-source, quadrupole, focusing 3982
  • P. Junphong, Mr. Ano, Mr. Lekprasert, Dr. Suwannakachorn, N. Thongnopparat, T. Vilaithong
    FNRF, Chiang Mai
  • H. Wiedemann
    SLAC, Menlo Park, California
  Funding: We would like to acknowledge the support of the Thailand Research Fund, the National Research Council of Thailand, the Thai Royal Golden Jubilee Scholarship Program, the Faculty of Science, and the Graduate School of Chiang Mai University.

At Fast Neutron Research Facility,the 150 kV-pulseds neutron generator is being upgraded to produce a 280-keV-pulsed-He beam for time-of-flight Rutherford backscattering spectrometry. It involves replacing the existing beam line elements by a multicusp ion source, a 400-kV accelerating tube, 45o-double focusing dipole magnet and quadrupole lens. The Multicusp ion source is a compact filament-driven of 2.6 cm in diameter and 8 cm in length. The current extracted is 20.4 μA with 13 kV of extraction voltage and 8.8 kV of Einzel lens voltage. The beam emittance has been found to vary between 6-12 mm mrad. The beam transport system has to be redesigned based on the new elements. The important part of a good pulsed beam depends on the pulsing system. The two main parts are the chopper and buncher. An optimized geometry for the 280 keV pulsed helium ion beam will be presented and discussed. The PARMELA code has been used to optimize the space charge effect, resulting in pulse width of less than 2 ns at a target. The calculated distance from a buncher to the target is 4.6 m. Effects of energy spread and phase angle between chopper and buncher have been included in the optimization of the bunch length.

FPAP020 Close-Coupling R-Matrix Approach to Simulating Ion-Atom Collisions for Accelerator Applications electron, coupling, background, simulation 1685
  • P. Stoltz, A. Prideaux
    Tech-X, Boulder, Colorado
  Funding: Funded by DOE under grant # DE-FG02-02ER83553.

We have implemented an R-matrix close coupling approach to calculate capture, ionization, stripping and excitation cross-sections for 0.5 to 8.0 MeV K+ incident on Ar. This is relevant to the High Current Experiment at Lawrence Berkley National Laboratory. These cross sections are used to model accelerator particle dynamics where background gasses can interfere with beam quality. This code is a semi-classical approach that uses quantum mechanics to describe the particle interactions and uses classical mechanics to describe the nuclei trajectories. We compare a hydrogenic approximation for K+ with a pseudo-potential approach. Further we are developing a variational approach to quickly determine the best pseudo-potential parameters. Since many R-Matrix computationalists use this pseudo-potential approach, this approach will be useful for helping generate cross sections for any collision system.

FPAP027 Hybrid Quantum Mechanical–Quasi-Classical Model for Evaluating Ionization and Stripping Cross Sections in Atom-Ion Collisions ion, electron, heavy-ion, plasma 1988
  • I. Kaganovich, R.C. Davidson, E. Startsev
    PPPL, Princeton, New Jersey
  Funding: Research supported by the U.S. Department of Energy.

Ion-atom ionization cross sections are needed in many applications employing the propagation of fast ions through matter. When experimental data or full-scale theoretical calculations are non-existent, approximate methods must be used. The most robust and easy-to-use approximations include the Born approximation of quantum mechanics and the quasi-classical approach utilizing classical mechanics together with the Bohr-Sommerfeld quantization rule.* The simplest method to extend the validity of both approaches is to combine them, i.e., use the two different approaches but only for the regions of impact parameters in which they are valid, and sum the results to obtain the total cross section. We have recently investigated theoretically and experimentally the stripping of more than 18 different pairs of projectile and target atoms in the range of 3-38 MeV/amu to study the range of validity of various approximations. The results of the modified approach agree better with the experimental data than either the Born approximation or the quasi-classical approach, applied separately.

*I. D. Kaganovich et al., "Formulary and scaling cross sections for ion-atom impact ionization," http://arxiv.org/abs/physics/0407140.

FPAP028 Ion Beam Pulse Interaction with Background Plasma in a Solenoidal Magnetic Field ion, plasma, electron, background 2062
  • I. Kaganovich, R.C. Davidson, E. Startsev
    PPPL, Princeton, New Jersey
  Funding: Research supported by the U.S. Department of Energy.

Background plasma can be used as an effective neutralization scheme to transport and compress intense ion beam pulses, and the application of a solenoidal magnetic field allows additional control and focusing of the beam pulse. Ion beam pulse propagation in a background plasma immersed in an applied solenoidal magnetic field has been studied both analytically and numerically with three different particle-in-cell codes (LSP, OOPIC-Pro and EDPIC) to cross-check the validity of the results. Very good charge and current neutralization is observed for high values of the solenoidal magnetic field.* However, for intermediate values of the solenoidal magnetic field, current neutralization is a complex process, and a sizable self-magnetic field is generated at the head of the beam. Collective wave excitations are also generated ahead of the beam pulse.

*I. D. Kaganovich, E. A. Startsev and R. C. Davidson, Nuclear Instruments and Methods in Physics Research A, in press (2004).

FPAP033 Beam Energy Scaling of Ion-Induced Electron Yield from K+ Ions Impact on Stainless Steel Surfaces electron, ion, heavy-ion, diagnostics 2287
  • M. Kireeff Covo, J.J. Barnard, R.H. Cohen, A. Friedman, D.P. Grote, S.M. Lund, A.W. Molvik, G.A. Westenskow
    LLNL, Livermore, California
  • D. Baca, F.M. Bieniosek, C.M. Celata, J.W. Kwan, P.A. Seidl, J.-L. Vay
    LBNL, Berkeley, California
  • J.L. Vujic
    UCB, Berkeley, California
  Funding: This work was performed under the auspices of the U.S. Department of Energy by University of California, LLNL under contract No. W-7405-Eng-48, and by LBNL under Contract DE-AC03-76F00098.

The cost of accelerators for heavy-ion inertial fusion energy (HIF) can be reduced by using the smallest possible clearance between the beam and the wall from the beamline. This increases beam loss to the walls, generating ion-induced electrons that could be trapped by beam space charge potential into an "electron cloud," which can cause degradation or loss of the ion beam. In order to understand the physical mechanism of production of ion-induced electrons we have measured impact of K+ ions with energies up to 400 KeV on stainless steel surfaces near grazing incidence, using the ion source test stand (STS-500) at LLNL. The electron yield will be discussed and compared with experimental measurements from 1 MeV K+ ions in the High-Current Experiment at LBNL.*

*A.W. Molvik et al., PRST-AB 7, 093202 (2004).

FPAT006 CHEF: An Interactive Program for Accelerator Optics Calculations lattice, optics, factory, controls 988
  • L. Michelotti, J.-F. Ostiguy
    Fermilab, Batavia, Illinois
  Funding: Fermilab is operated by Universities Research Association Inc. under Contract No. DE-AC02-76CH03000 with the United States Department of Energy.

We introduce CHEF, a program built on a "Collaborative Hierarchical Exploratory Framework" for doing optical calculations in accelerator physics. CHEF organizes and shares information between independent components that employ graphical user interfaces for interactive use. Among them are: a browser to display the beamline model's structure; a site viewer to show a line's geometry; phase space windows to oversee development of tracking calculations; a trace window to display the passage of a probe particle through beam position monitors; a plotter for displaying optical functions; a parser which constructs beamline models defined in MAD8 format and allows for interactive editing and debugging of the lattice files. Calculations are carried out by a hierarchy of C++ class libraries, most notably: MXYZPTLK handles automatic differentiation and differential algebra; BEAMLINE contains classes for modeling accelerator components; PHYSICS_TOOLKIT encapsulates specific calculations. Python bindings to these libraries and to CHEF's components, in conjunction with an embedded interpreter, provide a mechanism to extend and customize CHEF's functionality.

FPAT010 Automated Beam Steering Using Optimal Control controls, quadrupole, simulation, lattice 1213
  • C.K. Allen
    LANL, Los Alamos, New Mexico
  • E. Schuster
    Lehigh University, Bethlehem, Pennsylvania
  Funding: Work supported by the U.S. Department of Energy.

We present an optimal control strategy for beam steering where the operator can specify a variety of optimality conditions by selecting a parameter set describing an optimally steered beam. Novel approaches here include the ability to base optimality on the beam state throughout the entire beamline, rather than just at BPM locations. Moreover, we also may use the trajectory slope to base our optimality criteria. To achieve this feature we must introduce model dependency. Specifically, we predict the state of the beam from BPM measurements, the set-point of the steering magnets, and a model of beam behavior. The predictions are then used to calculate the optimum setting for steering magnets. The optimal control problem has rich mathematical structure that can be exploited and we cover some topics as they apply to accelerator systems.


FPAT014 Dynamic Visualization of SNS Diagnostics Summary Report and System Status SNS, diagnostics, beam-losses, emittance 1395
  • W. Blokland, D.J. Murphy, J.D. Purcell
    ORNL, Oak Ridge, Tennessee
  • A.V. Liyu
    RAS/INR, Moscow
  • C.D. Long
    Innovative Design, Knoxville, Tennessee
  • M. Sundaram
    University of Tennessee, Knoxville, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

The Spallation Neutron Source (SNS) accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is PC-based running Embedded Windows XP and LabVIEW. The diagnostics instruments communicate with the control system using the Channel Access (CA) protocol of the Experimental Physics and Industrial Control System (EPICS). This paper describes the Diagnostics Group’s approach to collecting data from the instruments, processing it, and presenting live in a summarized way over the web. Effectively, adding a supervisory level to the diagnostics instruments. One application of this data mining is the "Diagnostics Status Page" that summarizes the insert-able devices, transport efficiencies, and the mode of the accelerator in a compact webpage. The displays on the webpage change automatically to show the latest and/or most interesting instruments in use.

FPAT017 SNS Diagnostics Tools for Data Acquisition and Display diagnostics, SNS, beam-losses, scattering 1544
  • M. Sundaram
    University of Tennessee, Knoxville, Tennessee
  • W. Blokland
    ORNL, Oak Ridge, Tennessee
  • C.D. Long
    Innovative Design, Knoxville, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S Department of Energy.

The Spallation Neutron Source (SNS) accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1.0 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is PC-based and will run Windows for its OS and LabVIEW as its programming language. The diagnostics platform as well as other control systems and operator consoles use the Channel Access (CA) protocol of the Experimental Physics and Industrial Control System (EPICS) to communicate. This paper describes the tools created to evaluate the diagnostic instrument using our standard programming environment, LabVIEW. The tools are based on the LabVIEW Channel Access library and can run on Windows, Linux, and Mac OS X. The data-acquisition tool uses drop and drag to select process variables organized by instrument, accelerator component, or beam parameters. The data can be viewed on-line and logged to disk for later use. A drag and drop display creation tool supports the quick creation of graphical displays to visualize the data produced by the instruments without the need for programming.

FPAT031 High Energy Pulsed Power System for AGS Super Neutrino Focusing Horn power-supply, proton, pulsed-power, simulation 2191
  • W. Zhang, J. Sandberg, W.-T. Weng
    BNL, Upton, Long Island, New York
  Funding: Work performed under the auspices of the U.S. Department of Energy.

This paper present a preliminary design of a 300 kA, 2.5 Hz pulsed power system. This system will drive the focusing horn of proposed Brookhaven AGS Neutrino Super Beam Facility for Very Long Baseline Neutrino Oscillation Experiment. The peak output power of the horn pulsed power system will reach giga-watts, and the upgraded AGS will be capable of delivering 1 MW in beam power.

FPAT053 LabVIEW Library to EPICS Channel Access SNS, Spallation-Neutron-Source, diagnostics, scattering 3233
  • A.V. Liyu
    RAS/INR, Moscow
  • W. Blokland, D.H. Thompson
    ORNL, Oak Ridge, Tennessee
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

The Spallation Neutron Source (SNS) accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is PC-based and will run Windows for its OS and LabVIEW as its programming language. Data acquisition hardware will be based on PCI cards. There will be about 300 rack-mounted computers. The Channel Access (CA) protocol of the Experimental Physics and Industrial Control System (EPICS) is the SNS control system communication standard. This paper describes the approaches, implementation, and features of LabVIEW library to CA for Windows, Linux, and Mac OS X. We also discuss how the library implements the asynchronous CA monitor routine using LabVIEW’s occurrence mechanism instead of a callback function (which is not available in LabVIEW). The library is used to acquire accelerator data and applications have been built on this library for console display and data-logging.

FPAT071 Timing System for J-PARC linac, synchrotron, proton, power-supply 3853
  • F. Tamura
    JAERI/LINAC, Ibaraki-ken
  • J.C. Chiba, T. Katoh, M. Yoshii
    KEK, Ibaraki
  J-PARC has three accelerators running at the different repetition rates; a 400-MeV linac (50Hz), a 3-GeV rapid cycling synchrotron (RCS, 25Hz), and a 50-GeV synchrotron (MR). The linac and the RCS deliver the beam pluses to the different destinations in each cycle. The destinations are scheduled according to the machine operations. We define two kinds of timing, "scheduled timing" and "synchronization timing" so that the accelerators are operated with proper timing and the beam pulses are transported to the experimental facilities or the next accelerators. The J-PARC complex requires a stable and precise timing system. The system is based on a master clock generated by a synthesizer and the triggers are operated independently of the AC-line frequency. We describe the design of the J-PARC timing system and their configuration, and also present the hardware details.  
FPAT075 Using a Control System Ethernet Network as a Field Bus SNS, vacuum, cryogenics, diagnostics 3961
  • W.R. DeVan, S.E. Hicks, G.S. Lawson, W.H. Wagner, D.M. Wantland, E. Williams
    ORNL, Oak Ridge, Tennessee
  A major component of a typical accelerator distributed control system (DCS) is a dedicated, large-scale local area communications network (LAN). The SNS EPICS-based control system uses a LAN based on the popular IEEE-802.3 set of standards (Ethernet). Since the control system network infrastructure is available throughout the facility, and since Ethernet-based controllers are readily available, it is tempting to use the control system LAN for "fieldbus" communications to low-level control devices (e.g. vacuum controllers; remote I/O). These devices may or may not be compatible with the high-level DCS protocols. This paper presents some of the benefits and risks of combining high-level DCS communications with low-level "field bus" communications on the same network, and describes measures taken at SNS to promote compatibility between devices connected to the control system network.

Work supported by the U.S. Department of Energy under Contract DE-AC05-00OR22725.

FPAT089 A Parallel Simplex Optimizer and Its Application to High-Brightness Storage Ring Design dynamic-aperture, storage-ring, emittance, optics 4230
  • H. Shang, M. Borland
    ANL, Argonne, Illinois
  Funding: Work supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38.

Optimization is commonly used in accelerator design to find linear optics solutions. Such optimizations are usually fairly fast as linear optics computations are themselves fast. For high-brightness storage rings, optimization of nonlinear elements (e.g., sextupoles) is also important in obtaining sufficient dynamic aperture. However, this can be very time onsuming as the basic calculations are time consuming. We have developed an efficient parallel Simplex optimizer that runs on a Linux cluster. It can optimize the result of running essentially any program or script that returns a penalty function value. We have used this optimizer with elegant to optimize dynamic aperture of storage ring designs. We discuss the optimization algorithm and performance, design of penalty functions, and optimization results.

FPAT092 Optimized Beam Matching Using Extremum Seeking simulation, focusing, beam-transport, feedback 4269
  • E. Schuster
    Lehigh University, Bethlehem, Pennsylvania
  • C.K. Allen
    LANL, Los Alamos, New Mexico
  • M. Krstic
    UCSD, La Jolla, California
  The transport and matching problem for a low energy transport system is approached from a control theoretical viewpoint. The beam dynamics and transport section is modeled using the KV envelope equations. Principles of optimal control are applied to this model to formulate techniques which aid in the design of the transport and matching section. Multi-Parameter Extremum Seeking, a real-time non-model based optimization technique, is considered in this work for the lens tuning. Numerical simulations illustrate the effectiveness of this approach.  
FOAB001 Compact Neutron Generators for Medical, Home Land Security, and Planetary Exploration ion, ion-source, plasma, electron 49
  • J.P. Reijonen
    LBNL, Berkeley, California
  Funding: This work is being support by U.S. Department of Energy under contract No. DE-AC03-76SF00098.

The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0 – 9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration in form of neutron based, sub-surface hydrogen detection systems. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Three main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-compact axial neutron generator for elemental analysis applications. Current status of the neutron generator development with experimental data will be presented.