• 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

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.

• Y.-N. Rao
  TRIUMF, Vancouver
• D. Reistad
  TSL, Uppsala

• S.N. Andrianov, S. Edamenko
  St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg

• S.N. Andrianov
  St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg

• R. Bartolini
  Diamond, Oxfordshire
• F. Schmidt
  CERN, Geneva

• W.P. Jones, D.V. Baxter, V.P. Derenchuk, T. Rinckel, K. A. Solberg
  IUCF, Bloomington, Indiana

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.

• G.H. Gillespie, W. Hill
  G.H. Gillespie Associates, Inc., Del Mar, California
• G. Coutrakon, J. Hubbard, E. Sanders
  LLU/MC, Loma Linda, California

• C.M. Thomas, D.C. Faircloth, S.J.S. Jago
  CCLRC/RAL/ISIS, Chilton, Didcot, Oxon

• A. Zeller, V. Blideanu, R.M. Ronningen, B. Sherrill
  NSCL, East Lansing, Michigan
• R.C. Gupta
  BNL, Upton, Long Island, New York

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.

• A.A. Mikhailichenko
  Cornell University, Department of Physics, Ithaca, New York

• 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

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.

• 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.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

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.

• N.P. Luciano, Y. Makdisi, A.N. Nass, P. Thieberger, D. Trbojevic, A. Zelenski
  BNL, Upton, Long Island, New York

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.

• 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

• M. Re, F. Chines, G. Cuttone, M. Menna, E. Messina
  INFN/LNS, Catania
• J.-C. Bilheux, D.W. Stracener
  ORNL, Oak Ridge, Tennessee

• Y. Kawai, G. Alton, Y. Liu
  ORNL, Oak Ridge, Tennessee

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.

• Y. Kawai, G. Alton, J. O. Kiggans, D.W. Stracener
  ORNL, Oak Ridge, Tennessee

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.

• Y. Liu, H. Z. Bilheux, Y. Kawai
  ORNL, Oak Ridge, Tennessee

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.

• 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

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.

• Y. Zhang, G. Alton, Y. Kawai
  ORNL, Oak Ridge, Tennessee

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.

• K. Sakakibara, T. Hattori, N. Hayashizaki, T. Ito
  RLNR, Tokyo
• H. Kashiwagi
  JAERI/ARTC, Gunma-ken
• M. Okamura
  RIKEN, Saitama

• 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

hep-ph/0411046

• G. Pei
  IHEP Beijing, Beijing

• N.G. Reshetnyak, N. Aizatsky, A. Dovbnya, N.A. Dovbnya, V.V. Mytrochenko, V. Zakutin
  NSC/KIPT, Kharkov

• 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

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.

• M. Tawada, Y. Funakoshi, K. Ohmi
  KEK, Ibaraki

• P. Emma, L.D. Bentson, R.A. Erickson, H. Fieguth, J. Seeman, A. Seryi
  SLAC, Menlo Park, California

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.

• R.C. Fernow, J.C. Gallardo
  BNL, Upton, Long Island, New York

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.

• 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

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.

• 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

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.

• 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

• K. Yokoyama, M. Ikeda, K. Kakihara, T. Kamitani, S. Ohsawa, T. Sugimura, T. T. Takatomi
  KEK, Ibaraki

• M.-Y. Park, Y.-S. Cho, H.-S. Kim, H.-J. Kwon, K.T. Seol, Y.G. Song
  KAERI, Daejon

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.

• J. Norem, A. Hassanein, Z. Insepov, I. Konkashbaev
  ANL, Argonne, Illinois

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.

• T. Sugimura, M. Ikeda, K. Kakihara, T. Kamitani, S. Ohsawa, T. T. Takatomi, K. Yokoyama
  KEK, Ibaraki

• R.E. Laxdal, K. Fong, A.K. Mitra, T.C. Ries, I. Sekachev, G. Stanford, V. Zviagintsev
  TRIUMF, Vancouver

• 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

• 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

• 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

• B. Sinha, R.K. Bhandari, A. Chakrabarti
  DAE/VECC, Calcutta

• A. Chakrabarti, R.K. Bhandari
  DAE/VECC, Calcutta

• A. Coniglio, M.P. Pillon, S. Sandri
  ENEA C.R. Frascati, Frascati (Roma)
• M. D'Arienzo
  CNR/RFX, Padova

• S. Mayer, D. Forkel-Wirth, M. Fuerstner, H.G. Menzel, S. Roesler, C. Theis, H. Vincke
  CERN, Geneva

• M.A.C. Cummings
  Northern Illinois University, DeKalb, Illinois
• S. Ishimoto
  KEK, Ibaraki

• J.J. Error, D.R. Bruce, J.J. Fazekas, S.A. Helus, J.R. Maines
  ORNL, Oak Ridge, Tennessee

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.

• S.A. Helus, D.R. Bruce, J.J. Error, J.J. Fazekas, J.R. Maines
  ORNL, Oak Ridge, Tennessee

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.

• D.-O. Jeon
  ORNL, Oak Ridge, Tennessee

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.

• 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

• S. Reyes, L. Ahle, J.L. Boles, W. Stein
  LLNL, Livermore, California
• B.D. Wirth
  UCB, Berkeley, California

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.

• 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

• M. Boscolo, M. Ferrario, M.  Migliorati
  INFN/LNF, Frascati (Roma)
• F. Castelli, S. Cialdi, A.F. Flacco
  INFN-Milano, Milano

• 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

• S. Ohsawa, M. Ikeda, T. Sugimura, M. Tawada
  KEK, Ibaraki
• Y. Hozumi
  GUAS/AS, Ibaraki
• K. Kanno
  AET Japan, Inc., Kawasaki-City

• V. Zakutin, A. Dovbnya, N.G. Reshetnyak
  NSC/KIPT, Kharkov

• H. Wang, W. Gai, K.-J. Kim, W. Liu
  ANL, Argonne, Illinois

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.

• 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
  ,

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

• 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

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.

• M.A. Kempkes, N. Butler, J.A. Casey, M.P.J. Gaudreau, I. Roth
  Diversified Technologies, Inc., Bedford

• E. Sobieradzki, A.E. Wheelhouse
  e2v technologies, Chelmsford, Essex

• D. Cook, M. Catucci, J. Clare, P. W. Wheeler
  University of Nottingham, Nottingham
• J.S. Przybyla
  EEV, Chelmsford, Essex

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.

• 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

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

• M.D. Cole, E. Peterson, J. Rathke, T. Schultheiss
  AES, Medford, NY

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.

• 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

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.

• J. Norem
  ANL, Argonne, Illinois
• P. Bauer
  Fermilab, Batavia, Illinois
• J. Sebastian, D.N. Seidman
  NU, Evanston

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.

• H. Nishimura, W.E. Byrne
  LBNL, Berkeley, California

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.

• S.-K. Lee, B.H. Choi, K. R. Kim, LHR. Lee, B.-S. Park
  KAERI, Daejon

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.

• B.-S. Park, B.H. Choi, K. R. Kim, S.-K. Lee
  KAERI, Daejon

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.

• T.-S. F. Wang, J. T. Kwan
  LANL, Los Alamos, New Mexico

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.

• J.W.  Staples, R. Keller, A. Sessler
  LBNL, Berkeley, California
• W. Chou
  Fermilab, Batavia, Illinois
• P.N. Ostroumov
  ANL, Argonne, Illinois

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.

• 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

*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.

• 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

• 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

• 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

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.

• 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

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.

• 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

• F.M. Bieniosek, S. Eylon, P.K. Roy, S. Yu
  LBNL, Berkeley, California

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.

• V.E. Scarpine, C.W. Lindenmeyer, G. R. Tassotto
  Fermilab, Batavia, Illinois
• A.H. Lumpkin
  ANL, Argonne, Illinois

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.

• 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

• 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

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.

• 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

• 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

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.

• M. Satoh, K.  Furukawa, T. Suwada
  KEK, Ibaraki

• R.A. Richardson, F.W. Chambers, S. Falabella, G. Guethlein, B.A. Raymond, J.T. Weir
  LLNL, Livermore, California

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.

• P. Degtiarenko, D.W. Dotson, V.P. Popov
  Jefferson Lab, Newport News, Virginia

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.

• 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

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.

• 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

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.

• G.R. Murdoch
  ORNL, Oak Ridge, Tennessee

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.

• 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

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.

• V. Kain, J. Ramillon, R. Schmidt, K.V. Vorderwinkler, J. Wenninger
  CERN, Geneva

• E.W. Blackmore, A.S. Dowling, R. Ruegg, M.C. Stenning
  TRIUMF, Vancouver

• 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

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.

• B. Rusnak, M. Hall, S. Shen
  LLNL, Livermore, California

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.

• S. Bellavia, S.A. Kahn, H.G. Kirk, H. Ludewig, D. Raparia, N. Simos
  BNL, Upton, Long Island, New York

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.

• M. Holding, C.M. Hammons, B.R. Lang, G.R. Murdoch, K.G. Potter, R.T. Roseberry
  ORNL, Oak Ridge, Tennessee

• 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

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.

• X. Liu, Y. He, Y. Li
  Cornell University, Department of Physics, Ithaca, New York
• M.R. Adams
  Cornell University, Ithaca, New York

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.

• 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

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.

• D.W. Dotson, D.J. Seidman
  Jefferson Lab, Newport News, Virginia

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.

• Y.K. Batygin
  SLAC, Menlo Park, California

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.

• V. Bharadwaj, R. Pitthan, J. Sheppard, H. Vincke, J.W. Wang
  SLAC, Menlo Park, California

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.

• S.A. Kahn, M. Diwan
  BNL, Upton, Long Island, New York

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.

• C. Johnstone, A. Bross, I. Rakhno
  Fermilab, Batavia, Illinois

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.

• 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

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.

• 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

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.

• A. Tatum, J.R. Beene
  ORNL, Oak Ridge, Tennessee

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.

• 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

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.

• 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

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.

• S.S. Kurennoy, D.B. Barlow, B. Blind, A.J. Jason, N. Neri
  LANL, Los Alamos, New Mexico

• M.P. Hechler, R.I. Cutler, J.J. Error
  ORNL, Oak Ridge, Tennessee
• W.J. McGahern
  BNL, Upton, Long Island, New York

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.

• 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

• D. Li
  LBNL, Berkeley, California

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.

• S.E. Kopp
  The University of Texas at Austin, Austin, Texas

• 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

• S.M. Cousineau, V.V. Danilov, S. Henderson, J.A. Holmes, M.A. Plum
  ORNL, Oak Ridge, Tennessee

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.

• P.A. Schmelzbach, S.R.A. Adam, A. Adelmann, H. Fitze, G. Heidenreich, J.-Y. Raguin, U. Rohrer, P.K. Sigg
  PSI, Villigen

• F. Hinode, H. Hama, M. Kawai, A. Kurihara, A. Miyamoto, M. Mutoh, M. Nanao, Y. Shibasaki, K. Shinto, S. Takahashi, T. Tanaka
  LNS, Sendai

• V.P. Derenchuk, D.V. Baxter, A. Bogdanov, W.P. Jones, T. Rinckel, K. A. Solberg
  IUCF, Bloomington, Indiana

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.

• 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

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.

• M.A. Plum, M. Holding, T. McManamy
  ORNL, Oak Ridge, Tennessee

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.

• P. Junphong, Mr. Ano, Mr. Lekprasert, Dr. Suwannakachorn, N. Thongnopparat, T. Vilaithong
  FNRF, Chiang Mai
• H. Wiedemann
  SLAC, Menlo Park, California

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.

• P. Stoltz, A. Prideaux
  Tech-X, Boulder, Colorado

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.

• I. Kaganovich, R.C. Davidson, E. Startsev
  PPPL, Princeton, New Jersey

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.

• I. Kaganovich, R.C. Davidson, E. Startsev
  PPPL, Princeton, New Jersey

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).

• 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

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).

• L. Michelotti, J.-F. Ostiguy
  Fermilab, Batavia, Illinois

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.

• C.K. Allen
  LANL, Los Alamos, New Mexico
• E. Schuster
  Lehigh University, Bethlehem, Pennsylvania

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.

ckallen@lanl.gov

• 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

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.

• M. Sundaram
  University of Tennessee, Knoxville, Tennessee
• W. Blokland
  ORNL, Oak Ridge, Tennessee
• C.D. Long
  Innovative Design, Knoxville, Tennessee

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.

• W. Zhang, J. Sandberg, W.-T. Weng
  BNL, Upton, Long Island, New York

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.

• A.V. Liyu
  RAS/INR, Moscow
• W. Blokland, D.H. Thompson
  ORNL, Oak Ridge, Tennessee

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.

• F. Tamura
  JAERI/LINAC, Ibaraki-ken
• J.C. Chiba, T. Katoh, M. Yoshii
  KEK, Ibaraki

• W.R. DeVan, S.E. Hicks, G.S. Lawson, W.H. Wagner, D.M. Wantland, E. Williams
  ORNL, Oak Ridge, Tennessee

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

• H. Shang, M. Borland
  ANL, Argonne, Illinois

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.

• E. Schuster
  Lehigh University, Bethlehem, Pennsylvania
• C.K. Allen
  LANL, Los Alamos, New Mexico
• M. Krstic
  UCSD, La Jolla, California

• J.P. Reijonen
  LBNL, Berkeley, California

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.