Keyword: proton
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MOOBN3 Comparison of Accelerator Technologies for use in ADSS target, linac, cyclotron, SRF 4
 
  • W.-T. Weng, H. Ludewig, D. Raparia, M. Todosow, D. Trbojevic
    BNL, Upton, Long Island, New York, USA
  • P.M. McIntyre, A. Sattarov
    Texas A&M University, College Station, Texas, USA
 
  Funding: Work performed under the auspices of the US Department of Energy
Accelerator Driven Subcritical (ADS) fission is an interesting candidate basis for nuclear waste transmutation and for nuclear power generation. ADS can use either thorium or depleted uranium as fuel, operate below criticality, and consume rather than produce long-lived actinides. A case study with a hypothetical, but realistic nuclear core configuration is used to evaluate the performance requirements of the driver proton accelerator in terms of beam energy, beam current, duty factor, beam distribution delivered to the fission core, reliability, and capital and operating cost. Comparison between a CW IC and that of an SRF proton linac is evaluated. Future accelerator R&D required to improve each candidate accelerator design is discussed.
 
slides icon Slides MOOBN3 [1.540 MB]  
 
MOOBS4 Electron Cloud Experiments at Fermilab: Formation and Mitigation electron, vacuum, instrumentation, simulation 27
 
  • R.M. Zwaska
    Fermilab, Batavia, USA
 
  We have performed a series at Fermilab to explore the Electron Cloud phenomenon. The Main Injector will have its beam intensity increased four-fold in the Project X upgrade, and would be subject to instabilities from the Electron Cloud. We present measurements of the Cloud formation in the Main Injector and experiments with materials for the mitigation of the Cloud. An experimental installation of Titanium-Nitride (TiN) coated beam pipes has been under study in the Main Injector since 2009; this material was directly compared to an adjacent stainless chamber through Electron Cloud measurement with Retarding Field Analyzers (RFAs). Over the long period of running we were able to observe the secondary electron yield (SEY) change and correlate it with electron fluence, establishing a conditioning history. Additionally, the installation has allowed measurement of the electron energy spectrum, comparison of instrumentation techniques, and energy-dependent behavior of the Electron Cloud. Finally, a new installation, developed in conjunction with Cornell and SLAC, will allow direct SEY measurement of material samples irradiated in the accelerator.  
slides icon Slides MOOBS4 [2.975 MB]  
 
MOOCN1 Status of the LHC Operations and Physics Program luminosity, vacuum, injection, status 32
 
  • S. Redaelli
    CERN, Geneva, Switzerland
 
  The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) has just completed a successful first year of operation. In 2010, the primary goal to achieved a peak luminosity of 1032cm−2s−1 at a 7 TeV centre-of-mass energy was achieved and the machine achieved safely and reliably routine operation in the multi-MJ regime. The good results of 2010 have laid a solid foundation towards the achievement of the primary physics goal to deliver an integrated luminosity of 1 fb−1 in 2011. A fast and efficient LHC re-commissioning in 2011 lead already to a peak luminosity of 2.5×1032cm−2s−1 achieved in the fourth commissioning week. In this paper, the 2010 commissioning experience is reviewed and the present status and perspective are presented.  
slides icon Slides MOOCN1 [15.792 MB]  
 
MOOCN2 Tevatron Accelerator Physics and Operation Highlights luminosity, antiproton, collider, collimation 37
 
  • A. Valishev
    Fermilab, Batavia, USA
 
  Funding: Fermilab is operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The performance of the Tevatron collider demonstrated continuous growth over the course of Run II, with the peak luminosity reaching 4·1032 cm-2 s-1 and the weekly integration rate exceeding 70 pb-1. This report presents a review of the most important advances that contributed to this performance improvement, including beam dynamics modeling, precision optics measurements and stability control, implementation of collimation during low-beta squeeze. Algorithms employed for optimization of the luminosity integration are presented and the lessons learned from high-luminosity operation are discussed. Studies of novel accelerator physics concepts at the Tevatron are described, such as the collimation techniques using crystal collimator and hollow electron beam, and compensation of beam-beam effects.
 
slides icon Slides MOOCN2 [5.422 MB]  
 
MOOCN3 RHIC Polarized Proton Operation resonance, polarization, feedback, betatron 41
 
  • H. Huang, L. A. Ahrens, I.G. Alekseev, E.C. Aschenauer, G. Atoian, M. Bai, A. Bazilevsky, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, A. Dion, K.A. Drees, W. Fischer, C.J. Gardner, J.W. Glenn, X. Gu, M. Harvey, T. Hayes, L.T. Hoff, R.L. Hulsart, J.S. Laster, C. Liu, Y. Luo, W.W. MacKay, Y. Makdisi, M. Mapes, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, S. Nemesure, A. Poblaguev, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, W.B. Schmidke, V. Schoefer, F. Severino, D. Smirnov, K.S. Smith, D. Steski, D. Svirida, S. Tepikian, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, M. Wilinski, K. Yip, A. Zaltsman, A. Zelenski, K. Zeno, S.Y. Zhang
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
RHIC operation as the polarized proton collider presents unique challenges since both luminosity and spin polarization are important. With longitudinally polarized beams at the experiments, the figure of merit is LP4. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system has been installed to improve longitudinal match at injection and to increase luminosity. The beam dumps were upgraded to allow for increased bunch intensities. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control has also been improved this year. Additional efforts were put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point was chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper.
 
slides icon Slides MOOCN3 [2.331 MB]  
 
MOODN1 Results of Head-on Beam-beam Compensation Studies at the Tevatron antiproton, electron, emittance, simulation 67
 
  • A. Valishev, G. Stancari
    Fermilab, Batavia, USA
 
  Funding: Work supported by the Fermi Research Alliance, LLC under Contract DE-AC02-07CH11359 with the United States Department of Energy, and by the DOE through the US LHC Accelerator Research Program (LARP).
At the Tevatron collider, we studied the feasibility of suppressing the antiproton head-on beam-beam tune spread using a magnetically confined 5-keV electron beam with Gaussian transverse profile overlapping with the circulating beam. When electron cooling of antiprotons is applied in regular Tevatron operations, the head-on beam-beam effect on antiprotons is small. Therefore, we first focused on the operational aspects, such as beam alignment and stability, and on fundamental observations of tune shifts, tune spreads, lifetimes, and emittances. We also attempted two special collider stores with only 3 proton bunches colliding with 3 antiproton bunches, to suppress long-range forces and enhance head-on effects. We present here the results of this study and a comparison between numerical simulations and observations, in view of the planned application of this compensation concept to RHIC.
 
slides icon Slides MOODN1 [2.680 MB]  
 
MOODN2 Optimizing the Electron Beam Parameters for Head-on Beam-beam Compensation in RHIC electron, simulation, dynamic-aperture, gun 70
 
  • Y. Luo, W. Fischer, X. Gu, A.I. Pikin
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Head-on beam-beam compensation is adopted to compensate the large beam-beam tune spread from the proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). Two e-lenses are being built and to be in stalled near IP10 in the end of 2011. In this article we perform numeric simulation to investigate the effect of the electron beam parameters on the proton dynamics. The electron beam parameters include its transverse profile, size, current, offset and random errors in them.
 
slides icon Slides MOODN2 [0.601 MB]  
 
MOODS3 Studies of RF Noise Induced Bunch Lengthening at the LHC background, ion, emittance, cavity 91
 
  • T. Mastoridis, J.D. Fox, C.H. Rivetta
    SLAC, Menlo Park, California, USA
  • P. Baudrenghien, A.C. Butterworth, J.C. Molendijk
    CERN, Geneva, Switzerland
 
  Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
Radio Frequency noise induced bunch lengthening can strongly affect the Large Hadron Collider performance through luminosity reduction, particle loss, and other effects. Models and theoretical formalisms demonstrating the dependence of the LHC longitudinal bunch length on the RF station noise spectral content have been presented*,**. Initial measurements validated these studies and determined the performance limiting RF components. For the existing LHC LLRF implementation the bunch length increases with a rate of 1 mm/hr, which is higher than the intrabeam scattering diffusion and leads to a 27% bunch length increase over a 20 hour store. This work presents measurements from the LHC that better quantify the relationship between the RF noise and longitudinal emittance blowup. Noise was injected at specific frequency bands and with varying amplitudes at the LHC accelerating cavities. The experiments presented in this paper confirmed the predicted effects on the LHC bunch length due to both the noise around the synchrotron frequency resonance and the noise in other frequency bands aliased down to the synchrotron frequency by the periodic beam sampling of the accelerating voltage.
*T. Mastorides et.al., "RF system models for the LHC with Application to Longitudinal Dynamics,"
**T. Mastorides et.al., "RF Noise Effects on Large Hadron Collider Beam Diffusion"
 
slides icon Slides MOODS3 [0.644 MB]  
 
MOODS4 Dancing Bunches as van Kampen Modes impedance, synchrotron, damping, injection 94
 
  • A.V. Burov
    Fermilab, Batavia, USA
 
  Theory of van Kampen modes is applied to bunch longitudinal motion. Case of inductive impedance domination is studied in more details. Threshold for loss of Landau damping is found to be very sensitive to fine structure of the distribution function. Good agreement with the Tevatron's "dancing bunches" is obtained.  
slides icon Slides MOODS4 [0.408 MB]  
 
MOP030 Muon Capture for the Front End of a μ+μ- Collider collider, factory, target, focusing 157
 
  • D.V. Neuffer
    Fermilab, Batavia, USA
  • C. Y. Yoshikawa
    Muons, Inc, Batavia, USA
 
  We discuss the design of the muon capture front end for a μ±μ- Collider. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. The muons are then cooled and accelerated to high energy into a storage ring for high-energy high luminosity collisions. Our initial design is based on the somewhat similar front end of the International Design Study (IDS) neutrino factory.  
 
MOP032 High Pressure RF Cavity Test at Fermilab cavity, pick-up, solenoid, instrumentation 160
 
  • B.T. Freemire, P.M. Hanlet, Y. Torun
    IIT, Chicago, Illinois, USA
  • G. Flanagan, R.P. Johnson, M. Notani
    Muons, Inc, Batavia, USA
  • M.R. Jana, A. Moretti, M. Popovic, A.V. Tollestrup, K. Yonehara
    Fermilab, Batavia, USA
  • D.M. Kaplan
    Illinois Institute of Technology, Chicago, Illinois, USA
 
  Funding: Supported in part by DOE STTR grant DE-FG02-08ER86350
Operating a high gradient radio frequency cavity embedded in a strong magnetic field is an essential requirement for muon beam cooling. However, a magnetic field influences the maximum RF gradient due to focusing of dark current in the RF cavity. This problem is suppressed by filling the RF cavity with dense hydrogen gas. As the next step, we plan to explore the beam loading effect in the high pressure cavity by using a 400 MeV kinetic energy proton beam in the MuCool Test Area at Fermilab. We discuss the experimental setup and instrumentation.
 
 
MOP053 Measurement of Neutral Particle Contamination in the MICE Muon Beam target, collider, luminosity, background 199
 
  • L. Coney, R.R.M. Fletcher, G.G. Hanson
    UCR, Riverside, California, USA
 
  Funding: NSF
The Muon Ionization Cooling Experiment (MICE) is being built at the ISIS proton synchrotron at Rutherford Appleton Laboratory (RAL) to test ionization cooling of a muon beam. Production of particles in the MICE beamline begins with a titanium target dipping into the ISIS proton beam. The resulting pions are captured, momentum-selected, and fed into a 5T superconducting solenoid. This magnet contains the pions and their decay muons which are then sent through the rest of the MICE beamline toward the cooling channel. During recent data-taking, it was determined that there is a significant background contamination of neutral particles populating the MICE muon beam. This contamination creates unwanted triggers in MICE, thus reducing the percentage of useful data taken during running. This paper describes the analysis done with time-of-flight detectors, used to identify particle type, in order to understand the level of contamination in both positive and negative polarity muon beams.
 
 
MOP056 A Compact and High Performance Muon Capture Channel for Muon Accelerators factory, cavity, electron, lattice 208
 
  • D. Stratakis
    UCLA, Los Angeles, California, USA
  • J.C. Gallardo, R. B. Palmer
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work is funded by U.S. Dept. of Energy grant numbers DE AC02-98CH10886.
It is widely believed that a neutrino factory would deliver unparallel performance in studying neutrino mixing and would provide tremendous sensitivity to new physics in the neutrino sector. Here we will describe and simulate the front-end of the neutrino factory system, which plays critical role in determining the number of muons that can be accepted by the downstream accelerators. In this system, a proton bunch on a target creates secondaries that drift into a capture transport channel. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to nearly equal central energies, and initiates ionization cooling. For this, the muon beams are transported through sections containing high-gradient cavities and strong focusing solenoids. In this paper we present results of optimization and variation studies toward obtaining the maximum number of muons for a neutrino factory by using a compact transport channel.
Stratakis et al. Phys. Rev. ST Accel. Beams 14, 011001 (2011).
 
 
MOP061 Stability of the MICE Muon Beam Line emittance, target, radio-frequency, quadrupole 223
 
  • S.D. Blot
    University of Chicago, Chicago, Illinois, USA
 
  Funding: University of Chicago
The international Muon Ionization and Cooling Exper- iment (MICE) aims to demonstrate transverse beam emit- tance reduction for a muon beam. During the summer of 2010, data was taken using different configurations of the upstream beam line magnets to measure the optical pa- rameters of the muon beam and study the functionality of the beam line itself. Throughout this period of data taking, reference runs were taken with a fixed target configuration, and magnet settings which provide a muon beam with 200 MeV/c momentum and 6π 4D transverse emittance. Time of flight (TOF) detectors were used to measure many of the beam properties including emittance, particle identifi- cation, and profile. Analysis of these reference runs was carried out in order to determine the stability and repro- ducibility of the beam line data. This overall data quality check is essential to ensure the validity of measurements made so that further analysis can be carried out and that the muon beam is suitable for the MICE cooling channel.
 
 
MOP081 Proton Acceleration by Trapping in a Relativistic Laser Driven Uphill Plasma Snowplow laser, plasma, electron, simulation 247
 
  • A. Sahai, T.C. Katsouleas
    Duke ECE, Durham, North Carolina, USA
  • W.B. Mori, A. Tableman, J. Tonge, F.S. Tsung
    UCLA, Los Angeles, California, USA
 
  We explore a novel regime of proton and ion acceleration off of overdense Plasma created by a Laser pulse. In Coulomb explosion, Target Normal Sheath, Acoustic shock acceleration regimes the protons are neither high-energy nor monoenergetic enough for applications such as hadron radiation therapy, fast ignition fusion research and particle physics. This calls out for exploration of effective regimes of acceleration. The proposed Snowplow regime of acceleration uses a Snowplow of charge created by a relativistic Laser pulse at the critical density on a uphill Plasma density gradient. The relativistically moving Snowplow's space charge drags the protons and its velocity can be controlled to effectively trap the protons using laser pulse shape and the uphill density profile. We describe the principles behind this mechanism. We derive analytical expressions for the Snowplow velocity and its dependence on the parameter space. We primarily explore the density gradient and laser pulse shape to optimally accelerate protons from rest to the desired velocities. Preliminary, 1-D simulation results are presented and analyzed.  
 
MOP093 Precision Monitoring of Relative Beam Intensity target, monitoring, background, dipole 271
 
  • N.J. Evans, S.E. Kopp
    The University of Texas at Austin, Austin, Texas, USA
  • E. Prebys
    Fermilab, Batavia, USA
 
  Funding: U.S. Department of Energy.
For future experiments at the intensity frontier, precise and accurate knowledge of beam time structure will be critical to understanding backgrounds. The proposed Mu2e experiment will utilize ~150nsec (FWHM) bunches of 107 protons at 8 GeV with a bunch-to-bunch period of 1.7 microseconds. The out-of-bunch beam must be suppressed by a factor of 10-9 relative to in-bunch beam and continuously monitored. I propose a Cerenkov based particle telescope to measure secondary production from beam interactions in a several tens of microns thick foil. Correlating timing information with beam passage allows the determination of relative beam intensity to arbitrary precision given a sufficiently long integration time. The goal is to verify out-of-bunch extinction to the level 10-6 in the span of several seconds. This allows near real-time monitoring of the initial extinction of the beam slow extracted from Fermilab's Debuncher before a system of AC dipoles and collimators, which will provide the final extinction. The effect on beam emittance is minimal, allowing the necessary continuous measurement. I will present the detector design and results of a test in Fermilab's MI-12 beamline.
 
 
MOP106 Electron Acceleration via Positron Driven Plasma Wakefield Accelerator electron, positron, plasma, wakefield 295
 
  • S.F. Pinkerton, P. Muggli
    USC, Los Angeles, California, USA
  • W. An, W.B. Mori
    UCLA, Los Angeles, California, USA
 
  Funding: Work supported by US DoE and NSF.
We show that a positron bunch with parameters accessible at FACET can excite a stable plasma wakefield over a few meters and a witness electron bunch experiences an accelerating gradient on the order of 10 GeV/m. Initial simulations show that the positron drive bunch is strongly affected by the transverse components of the wakefield: the positron bunch evolves significantly, which affects both the wakefield and witness bunch dynamics. Various solutions are presented, of which the positron-electron train shceme generates a desirable wakefield.
 
 
MOP108 Simulation Study of Proton-Driven PWFA Based on CERN SPS Beam plasma, wakefield, simulation, acceleration 301
 
  • G.X. Xia, A. Caldwell
    MPI-P, München, Germany
  • C. Huang
    LANL, Los Alamos, New Mexico, USA
  • W.B. Mori
    UCLA, Los Angeles, California, USA
 
  We have proposed an experimental study of the proton-driven plasma wakefield acceleration by using proton beam from the CERN SPS. In this paper, the particle-in-cell (PIC) simulation of the SPS beam-driven plasma wakefield acceleration is introduced. By varying the beam parameters and plasma parameters, simulation shows that electric fields in excess of 1 GeV/m can be achieved.  
 
MOP142 Development of Picosecond CO2 Laser Driver for an MeV Ion Source laser, ion, plasma, ion-source 355
 
  • S. Tochitsky, D.J. Haberberger, C. Joshi
    UCLA, Los Angeles, California, USA
 
  Funding: This work is supported by DOE grant DE-FG02-92ER40727.
Laser-Driven Ion Acceleration in thin foils has demonstrated high-charge, low-emittance MeV ion beams with a picosecond duration. Such high-brightness beams are very attractive for a compact ion source or an injector for RF accelerators. However in the case of foils scaling of the pulse repetition rate and improving shot-to-shot reproducibility is a serious challenge. CO2 laser-plasma interactions provide a possibility for using a debris free gas jet for target normal sheath acceleration of ions. Gas jets have the advantage of precise density control around the critical plasma density for 10 um pulses (1019 cm-3) and can be run at 1-10 Hz. The master oscillator–power amplifier CO2 laser system at the UCLA Neptune Laboratory is being upgraded to generate 1 J, 3 ps pulses at 1Hz. For this purpose, a new 8 atm CO2 module is used to amplify a 3 ps pulse to ~10 GW level. Final amplification is realized in a 1-m long TEA CO2 amplifier, for which the bandwidth necessary for 3 ps pulses is provided by the field broadening mechanism. Modeling of the pulse amplification shows that ~0.3 TW power is achievable that should be sufficient for producing 1-3 MeV H+ protons from the gas plasma.
 
 
MOP143 Enhanced Laser-Driven Ion Acceleration via Forward Raman Scattering in a Ramped Gas Target laser, plasma, target, electron 358
 
  • S. Tochitsky, D.J. Haberberger, C. Joshi, W.B. Mori, F.S. Tsung
    UCLA, Los Angeles, California, USA
 
  Funding: This work is supported by DOE grant DE-FG02-92ER40727.
CO2 laser-plasma interactions provide a unique parameter space for using a gas jet for Target Normal Sheath Acceleration (TNSA) of ions instead of a thin foil target. The generation of 1-5 MeV protons from the interaction of a 3 ps TW CO2 laser pulse with a gas target with a peak density around the critical plasma density (1019 cm-3) has been studied by 2D particle-in-cell simulations. The proton acceleration in the preformed plasma, having similar to the gas jet symmetric, linearly ramped density distribution, occurs via formation of a sheath of hot electrons on the back surface of the target. The maximum energy of the hot electrons and, hence net acceleration of protons is mainly defined by Forward Raman scattering instability in the underdense part of the plasma. This mechanism of an additional heating of electrons is strongly affected by nonlinear laser-plasma interactions and results in the proton energy enhancement by more than an order of magnitude in comparison with the regular ponderomotive force scaling of TNSA. Forward directed ion beams from a gaseous target can find an application as a high-brightness ion source-injector.
 
 
MOP153 High Efficiency Laser Ion Acceleration in Low Density Plasmas acceleration, plasma, laser, simulation 376
 
  • E. d'Humières, V. Tikhonchuk
    CELIA, Talence, France
 
  Laser driven sources of high energy ions commonly use thin solid foils. A gaseous target can also produce ion beams with characteristics comparable to those obtained with solid targets. Using Particle-In-Cell simulations, we have studied in detail ion acceleration with high intensity laser pulses interacting with low density plasmas. A two-step acceleration process can be triggered: first, ions are accelerated in volume by electric fields generated by hot electrons, second, the ion energy is boosted in a strong electrostatic shock. 2D and 3D simulations show the potential of this regime. It is possible to model separately these two steps. In the first step a hot electron population and a descending density profile are necessary, and the second step develops if a fast proton wave enters in a low density plasma.  
 
MOP154 Prospects for Proton Accelerators Driven by the Radiation Pressure from a Sub-PW CO2 Laser laser, plasma, ion, target 379
 
  • M.N. Polyanskiy, I. Ben-Zvi, I. Pogorelsky, V. Yakimenko
    BNL, Upton, Long Island, New York, USA
  • Z. Najmudin
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
 
  Funding: DOE
Laser acceleration of ion beams is normally realized via irradiating thin-foil targets with near-IR solid-state lasers with up to petawatt (PW) peak power. Despite demonstration of significant achievements, further progress towards practical application of such beam sources is hindered by the challenges inherent in constructing still more intense and higher-contrast lasers. Our recent studies of the radiation pressure acceleration indicate that the combination of a 10-μm CO2 laser with a gas jet target offers a unique opportunity for a breakthrough in the field. Strong power scaling of this regime holds the promise of achieving the hundreds of MeV proton beams with just sub-PW CO2 laser pulses. Generation of such pulses is a challenging task. We discuss a strategy of the CO2 laser upgrade aimed to providing a more compact and economical hadron source for cancer therapy. This include optimization of the method of the 10μm short-pulse generation, higher amplification in the CO2 gas under combined isotopic and power broadening effects, and the pulse shortening to a few laser cycles (150-200 fs) via self-chirping in the laser-produced plasma and the consecutive dispersive compression.
 
 
MOP190 Precision, Absolute Proton Beam Polarization Measurements at 200 MeV Beam scattering, polarization, target, monitoring 444
 
  • G. Atoian, A. Zelenski
    BNL, Upton, Long Island, New York, USA
  • A. Bogdanov, M.F. Runtso
    MEPhI, Moscow, Russia
  • E.J. Stephenson
    IUCF, Bloomington, Indiana, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
A new polarimeter for absolute proton beam polarization measurements at 200 MeV to accuracy better than ±0.5% has been developed as a part of the RHIC polarized source upgrade. The polarimeter is based on the elastic proton-carbon scattering at 16.2 degree angle, where the analyzing power is close to 100% and was measured with high accuracy. The elastically and in-elastically scattered protons are clearly identified by the difference in the propagation through variable copper absorber and energy deposition of the protons in the detectors. The 16.2 degree elastic scattering polarimeter was used for calibration of a high rate inclusive 12 degree polarimeter for the on-line polarization tuning and monitoring. This technique can be used for accurate polarization measurements in energy range of at least 160-250 MeV.
 
 
MOP191 RHIC Spin Flipper Status and Simulation Studies dipole, resonance, betatron, synchrotron 447
 
  • M. Bai, W.C. Dawson, Y. Makdisi, F. Méot, P. Oddo, C. Pai, P.H. Pile, T. Roser
    BNL, Upton, Long Island, New York, USA
 
  Funding: This work was supported by Department of Energy of U.S.A and RIKEN, Japan
The commissioning of the RHIC spin flipper in the RHIC Blue ring during the RHIC polarized proton run in 2009 showed the detrimental effects of global vertical coherent betatron oscillation induced by the 2-AC dipole plus 4-DC dipole configuration *. Additional three AC dipoles were added to the RHIC spin flipper in the RHIC Blue ring during the summer of 2010 to eliminate the vertical coherent betatron oscillations outside the spin flipper [2]. This new design is scheduled to be commissioned during the RHIC polarized proton run in 2011. This paper presents the status of the system as well as latest simulation results.
* M. Bai , T. Roser, C. Dawson, Y. Makdisi, W. Meng, F. Meot, P. Oddo, C. Pai, P. Pile, RHIC Spin Flipper New Design and Commissioning Plan, IPAC10 proceedings, IPAC 2010, Kyoto, Japan, 2010
 
 
MOP206 Calibration and Performance of a Secondary Emission Chamber as a Beam Intensity Monitor ion, vacuum, electron, heavy-ion 480
 
  • M. Sivertz, I.-H. Chiang, A. Rusek
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy and with support of NASA.
We report on a study of the behavior of a secondary emission chamber (SEC). We show the dependence of the SEC signal on the charge and velocity of the primary beam for beams of protons, and heavy ions including Helium, Neon, Chlorine and Iron. We fill the SEC with a selection of different gases including Hydrogen, Helium, Nitrogen, Argon, and air, studying the SEC response when it is acting as an ion chamber. We also investigate the behavior of the SEC at intermediate pressures between 10-8 torr and atmospheric pressure.
 
 
MOP209 Proposed Scattered Electron Detector System as One of the Beam Overlap Diagnostic Tools for the New RHIC Electron Lens electron, scattering, solenoid, diagnostics 489
 
  • P. Thieberger, E.N. Beebe, C. Chasman, W. Fischer, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, R.F. Lambiase, Y. Luo, M.G. Minty, C. Montag, M. Okamura, A.I. Pikin, Y. Tan, J.E. Tuozzolo, W. Zhang
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
An electron lens for head-on beam-beam compensation planned for RHIC requires precise overlap of the electron and proton beams which both can have down to 0.3 mm rms transverse radial widths along the 2m long interaction region. Here we describe a new diagnostic tool that is being considered to aid in the tuning and verification of this overlap. Some of ultra relativistic protons (100 or 250 GeV) colliding with low energy electrons (2 to 10 keV) will transfer sufficient transverse momentum to cause the electrons to spiral around the magnetic guiding field in a way that will make them detectable outside of the main solenoid. Time-of-flight of the halo electron signals will provide position-sensitive information along the overlap region. Scattering cross sections are calculated and counting rate estimates are presented as function of electron energy and detector position.
 
 
MOP212 Quadrupole Beam-Based Alignment in the RHIC Interaction Regions quadrupole, controls, alignment, focusing 498
 
  • J.M. Ziegler
    BNL, Upton, Long Island, New York, USA
  • T. Satogata
    JLAB, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements.
 
 
MOP218 High Level Software for 4.8 Ghz LHC Schottky System controls, ion, betatron, status 507
 
  • J. Cai, E.S.M. McCrory, R.J. Pasquinelli
    Fermilab, Batavia, USA
  • M. Favier, O.R. Jones
    CERN, Geneva, Switzerland
  • A. Jansson
    ESS, Lund, Sweden
  • T.E. Lahey
    SLAC, Menlo Park, California, USA
 
  A high level software package has been developed for a 4.8GHz Schottky system installed in the LHC at CERN. It has two main components. The first is a monitor application continuously running on a dedicated server as a daemon process to acquire the FFT traces, perform data analysis, publish results and do archiving. The second is a graphical user interface to display the FFT traces and various measurement results. It also allows the end user to change the settings for the front-end electronics such as the local oscillators, bunch selector, amplifier gains etc. Data analysis with curve fitting poses a big challenge due to the strong coherent signals that are often observed superimposed onto the Schottky sidebands. A method has been successfully created to remove the coherent spikes to enable curve fitting on the underlying signals, with the ultimate aim of providing reliable tune, momentum spread, chromaticity and emittance measurements for LHC beams with no external excitation.  
 
MOP222 Operational Use of Ionization Profile Monitors in the Fermilab Main Injector antiproton, injection, controls, vacuum 519
 
  • D.K. Morris, P. Adamson, D. Capista, I. Kourbanis, T. Meyer, K. Seiya, D. Slimmer, M.-J. Yang, J.R. Zagel
    Fermilab, Batavia, USA
 
  Funding: Operated by the Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Ionization profile monitors (IPMs) are used in the Fermilab Main Injector (MI) for injection lattice matching and to measure transverse emittance of the beam during acceleration. The IPMs provide a periodic, non-destructive means for emittance measurements where other techniques are not applicable. As Fermilab is refocusing its attention on the intensity frontier, non-intercepting diagnostics such as IPMs are expected to become even more important. This paper gives an overview of the operational use of IPMs for emittance measurements and injection lattice matching measurements at Fermilab, and summarizes the future plans.
 
 
MOP225 Initial Characterization of a Commercial Electron Gun for Profiling High Intensity Proton Beams in Project X electron, gun, solenoid, emittance 525
 
  • R.M. Thurman-Keup, A.S. Johnson, A.H. Lumpkin, J.C.T. Thangaraj, D.H. Zhang
    Fermilab, Batavia, USA
  • W. Blokland
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Measuring the profile of a high intensity proton beam is problematic in that traditional invasive techniques such as flying wires don't survive the encounter with the beam. One alternative is the use of an electron beam as a probe of the charge distribution in the proton beam as was done at the Spallation Neutron Source at ORNL. Here we present an initial characterization of the beam from a commercial electron gun from Kimball Physics, intended for use in the Fermilab Main Injector for Project X.
 
 
MOP235 LANSCE Wire Scanning Diagnostics Device Prototype vacuum, linac, diagnostics, acceleration 551
 
  • S. Rodriguez Esparza, Y.K. Batygin, J.D. Gilpatrick, M.E. Gruchalla, A.J. Maestas, C. Pillai, J.L. Raybun, F.D. Sattler, J.D. Sedillo, B.G. Smith
    LANL, Los Alamos, New Mexico, USA
 
  The Accelerator Operations & Technology Division at Los Alamos National Laboratory operates a linear particle accelerator which utilizes 110 wire scanning diagnostics devices to gain position and intensity information of the proton beam. In the upcoming LANSCE improvements, 51 of these wire scanners are to be replaced with a new design, up-to-date technology and off-the-shelf components. This document outlines the requirements for the mechanical design of the LANSCE wire scanner and presents the recently developed linac wire scanner prototype. Additionally, this document presents the design modifications that have been implemented into the fabrication and assembly of this first linac wire scanner prototype. Also, this document will present the design for the second and third wire scanner prototypes being developed. These last two prototypes belong to a different section of the particle accelerator and therefore have slightly different design specifications. Lastly, the paper concludes with a plan for future work on the wire scanner development.  
 
MOP238 Laser Compton Proton Polarimetry Revisited photon, laser, electron, scattering 560
 
  • A.N. Stillman
    Private Address, Huntington, USA
 
  Compton polarimetry of polarized proton beams is more feasible now than it was in 1995*, when I first estimated the laser requirements of a polarimeter using the available laser technology. New methods of high energy photon generation make the technique of Compton proton polarimetry a viable option for polarized proton beams. Since the analyzing power of a Compton polarimeter increases with photon energy and the count rate of the polarimeter increases with the laser intensity, the new laser technologies available today imply the construction of a working device with reasonable effort. I estimate the device parameters necessary for a working Compton polarimeter at RHIC using several methods of high energy photon generation.
* Arnold Stillman, in Proceedings of the 1995 Particle Accelerator Conference, 1995, p.2560
 
 
MOP256 Upgrading the Data Acquisition and Control System of the LANSCE LINAC controls, linac, EPICS, neutron 588
 
  • D. Baros
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work has benefited from the use of the LANSCE at LANL. This facility is funded by the US DOE and operated by LANS for NSSA under Contract DE-AC52-06NA25396.
Los Alamos National Laboratory LANL is in the process of upgrading the control system for the Los Alamos Neutron Science Center (LANSCE) linear accelerator. The 38 year-old data acquisition and control equipment is being replaced with COTS hardware. An overview of the current system requirements and how the National Instruments cRIO system meets these requirements will be given, as well as an update on the installation and operation of a prototype system in the LANSCE LINAC.
LANL Release Number: LA-UR 10-06605
 
 
TUOAN2 High Luminosity Electron-Hadron Collider eRHIC electron, luminosity, linac, ion 693
 
  • V. Ptitsyn, E.C. Aschenauer, M. Bai, J. Beebe-Wang, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, R. Calaga, X. Chang, A.V. Fedotov, H. Hahn, L.R. Hammons, Y. Hao, P. He, W.A. Jackson, A.K. Jain, E.C. Johnson, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, G.T. McIntyre, W. Meng, M.G. Minty, B. Parker, A.I. Pikin, T. Rao, T. Roser, B. Sheehy, J. Skaritka, S. Tepikian, R. Than, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, Q. Wu, W. Xu, A. Zelenski
    BNL, Upton, Long Island, New York, USA
  • E. Pozdeyev
    FRIB, East Lansing, Michigan, USA
  • E. Tsentalovich
    MIT, Middleton, Massachusetts, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We present the design of future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC. We plan on adding 20 (potentially 30) GeV energy recovery linacs to accelerate and to collide polarized and unpolarized electrons with hadrons in RHIC. The center-of-mass energy of eRHIC will range from 30 to 200 GeV. The luminosity exceeding 1034 cm-2 s-1 can be achieved in eRHIC using the low-beta interaction region with a 10 mrad crab crossing. We report on the progress of important eRHIC R&D such as the high-current polarized electron source, the coherent electron cooling and the compact magnets for recirculating passes. A natural staging scenario of step-by-step increases of the electron beam energy by builiding-up of eRHIC's SRF linacs and a potential of adding polarized positrons are also presented.
 
slides icon Slides TUOAN2 [4.244 MB]  
 
TUOAN4 Feedback Scheme for Kink Instability in ERL Based Electron Ion Collider feedback, electron, luminosity, ion 699
 
  • Y. Hao, V. Litvinenko, V. Ptitsyn
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Kink instability presents one of the limiting factors from achieving higher luminosity in ERL based electron ion collider (EIC). However, we can take advantage of the flexibility of the linac and design a feedback system to cure the instability. This scheme raises the threshold of kink instability dramatically and provides for higher luminosity. We studied the effectiveness of this system and its dependence on the amplitude and phase of the feedback. In this paper we present results of theses studies of this scheme and describe its theoretical and practical limitations.
 
slides icon Slides TUOAN4 [1.193 MB]  
 
TUOBN5 A Proposed Experimental Test of Proton-Driven Plasma Wakefield Acceleration Based on CERN SPS plasma, wakefield, electron, acceleration 718
 
  • G.X. Xia, A. Caldwell
    MPI-P, München, Germany
  • W. An, C. Joshi, W. Lu, W.B. Mori
    UCLA, Los Angeles, California, USA
  • R.W. Assmann, F. Zimmermann
    CERN, Geneva, Switzerland
  • R.A. Fonseca, N.C. Lopes, J. Vieira
    Instituto Superior Tecnico, Lisbon, Portugal
  • C. Huang
    LANL, Los Alamos, New Mexico, USA
  • K.V. Lotov
    BINP SB RAS, Novosibirsk, Russia
  • P. Muggli
    USC, Los Angeles, California, USA
  • A.M. Pukhov
    HHUD, Dusseldorf, Germany
  • L.O. Silva
    IPFN, Lisbon, Portugal
 
  Proton-driven plasma wakefield acceleration (PDPWA) has been proposed as an approach to accelerate electron beam to TeV energy regime in a single passage of plasma channel. An experimental test is recently proposed to demonstrate the capability of PDPWA by using proton beams from the CERN SPS. The preparation of experiment is introduced. The particle-in-cell simulation results based on realistic beam parameters are presented.  
slides icon Slides TUOBN5 [2.208 MB]  
 
TUOBN6 Production of 25 MeV Protons in CO2 Laser-Plasma Interactions in a Gas Jet plasma, laser, ion, target 721
 
  • D.J. Haberberger, C. Gong, C. Joshi, S. Tochitsky
    UCLA, Los Angeles, California, USA
 
  Funding: This work is supported by DOE grant DE-FG02-92ER40727 and NSF grant PHY-0936266
At the Neptune Laboratory at UCLA, we have developed a high-power CO2 MOPA laser system which produces world record multi-terawatt 10um pulses. The CO2 laser pulses consist of a train of 3ps pulses separated by 18ps, each with a peak power of up to 4TW and a total pulse train energy of ~100J. These relativistic laser pulses are applied for Laser Driven Ion Acceleration in an H2 gas jet operated around the critical density of 1019 cm-3 for 10um light using the Target Normal Sheath Acceleration mechanism. The laser is focused into the gas jet reaching a normalized field strength of a0~2 in vacuum. For these conditions, protons with a maximum energy of 25MeV and a narrow energy spread of ΔE/E < 1% are recorded. Initial analysis of these experimental results shows a stronger scaling of the proton energy than that predicted from the ponderomotive force, and highlights the importance of an accumulated effect of multiple CO2 laser pulses lasting over 100ps. The temporal dynamics of the overdense plasma slab are probed with a picosecond 532nm pulse and the results will be discussed.
 
 
TUP004 GEANT4 Modelling of Heat Deposition into the ISIS Muon Target target, neutron, ion, simulation 814
 
  • A. Bungau, R. Cywinski
    University of Huddersfield, Huddersfield, United Kingdom
  • R.J. Barlow
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C. Bungau
    Manchester University, Manchester, United Kingdom
  • P.J.C. King, J.S. Lord
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
 
  The energy deposition on the ISIS muon target and the temperature profiles are analysed in this paper. The thermal modelling is performed using the GEANT4 Monte Carlo code. Heat deposition patterns are also simulated for alternative target geometries. Energy deposition in the collimators is also discussed.  
 
TUP016 Beam Brightness Booster with Charge Exchange Injection and Superintense Circulating Beams Production ion, brightness, electron, target 844
 
  • V.G. Dudnikov, C.M. Ankenbrandt
    Muons, Inc, Batavia, USA
 
  An increase of intensity and brightness of proton beam by means of charge exchange injection and devices developed for this experiment are considered. First observation of e-p instability, explanation and damping by feed back are discussed. Discovery of “cesiation effect” leading to multiple increase of negative ion emission from gas discharges and development of surface-plasma sources for intense high brightness negative ion beams production are considered. By these developments were prepared a possibility for production of stable “superintense” circulating beam with intensity and brightness fare above space charge limit. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. New opportunity for simplification of the superintense beam production is promised by developing of nonlinear close to integrable focusing system with broad spread of betatron tune and the broad bend feed back system for e-p instability suppression.  
 
TUP020 A New Continuous Muon Beam Line Using a Highly Efficient Pion Capture System at RCNP solenoid, target, simulation, dipole 856
 
  • H. Sakamoto, Y. Kuno, A. Sato
    Osaka University, Osaka, Japan
  • S. Cook, R.T.P. D'Arcy
    UCL, London, United Kingdom
  • M. Fukuda, K. Hatanaka
    RCNP, Osaka, Japan
  • T. Ogitsu, A. Yamamoto, M.Y. Yoshida
    KEK, Ibaraki, Japan
 
  A new muon source with continuous time structure is under construction at Research Center of Nuclear Physics (RCNP), Osaka University. The ring cyclotron of RCNP can provide 400W 400MeV proton beam. Using this proton beam, the MuSIC produces a high intense muon beam. The target muon intensity is 108 muons/second, which is achieved by a pion capture with great efficiency to collect pions and muons using a solenoidal magnetic field. A pion production target system is located in a 3.5 Tesla solenoidal magnetic field generated by a super-conducting solenoid magnet. The proton beam hits the target, and backward pions and muons are captured by the field. Then they are transported by a curved solenoid beam line to experimental apparatus. The construction has been started in 2010, and would be finished in 5 years. We plan to carry out not only an experiment to search the lepton flavor violating process but also other experiments for muon science and their applications using the intense muon beam.  
 
TUP084 Design of Single Spoke Resonators for Project X cavity, linac, ion, niobium 982
 
  • L. Ristori, S. Barbanotti, M.S. Champion, M.H. Foley, I.G. Gonin, C.J. Grimm, T.N. Khabiboulline, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  Project X is based on a 3 GeV CW superconducting linac and is currently in the R&D phase awaiting CD-0 approval. The low-energy section of the Project X H-linac includes three types of super-conducting single spoke cavities operating at 325 MHz. SSR0 (26 cavities), SSR1 (18 cavities) and SSR2 (44 cavities) have a geometrical beta of = 0.11, 0.21 and 0.4 respectively. Single spoke cavities were selected for the linac in virtue of their higher r/Q. In this paper we present the decisions and analyses that lead to the final designs. Electro-magnetic and mechanical finite element analyses were performed with the purpose of optimizing the electro-magnetic design, minimizing frequency shifts due to Helium bath pressure fluctuations and providing a pressure rating for the resonators that allow their use in the cryomodules.  
 
TUP146 Large Aperture Quadrupole Magnets for ISIS TS-1 and TS-2 quadrupole, dipole, target, neutron 1103
 
  • S.M. Gurov, A.M. Batrakov, M.F. Blinov, F.A. Emanov, V.V. Kobets, V.A. Polukhin, A.S. Tsyganov, P. Vobly, T.A. Yaskina
    BINP SB RAS, Novosibirsk, Russia
  • S.J.S. Jago, J. Shih, S.F.S. Tomlinson
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
 
  The ISIS pulsed neutron and muon source at the Rutherford Appleton Laboratory has two target stations TS-1 and TS-2. Budker Institute of Nuclear Physics developed, produced and delivered seven type Q13 quadrupole magnets with an aperture diameter of 310 mm for TS-2 beam transfer line. Later an additional three quadrupoles with integrated dipole coils were developed and delivered to ISIS TS1. To improve the field quality across the full current range a special pole profile and end chamfer were designed using the MERMAID code. The magnetic field map was measured by a set of Hall probes. Moreover, BINP produced a rotating coil with radius 120 mm for field quality measurements.  
 
TUP164 Magnetic Design of e-lens Solenoid and Corrector System for RHIC solenoid, dipole, electron, superconducting-magnet 1130
 
  • R.C. Gupta, M. Anerella, W. Fischer, G. Ganetis, A.K. Ghosh, X. Gu, A.K. Jain, P. Kovach, A. Marone, A.I. Pikin, S.R. Plate, P. Wanderer
    BNL, Upton, Long Island, New York, USA
 
  Funding: This work is supported by the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.
As a part of the proposed electron lens system for RHIC, two 6 T, 200 mm aperture, 2.5 meter long superconducting solenoids are being designed and built at BNL. Because of several demanding requirements this has become a unique and technologically advanced magnet. For example, the field lines on axis must be straight over the length of the solenoid within ±50 microns. Since this is beyond the normal construction techniques, a correction package becomes an integral part of the design for which a new design has been developed. In addition, a minimum of 0.3 T field is required along the electron beam trajectory in the space between magnets. To achieve this fringe field superconducting solenoidal coils have been added at the two ends of the main solenoid. The main solenoid itself is a challenging magnet because of the high Lorentz forces and stored energy associated with the large aperture and high fields. An innovative structure has been developed to deal with the large axial forces at the ends. This paper will summarize the magnetic design and optimization of the entire package consisting of the main solenoid, the fringe field solenoids, and the corrector system.
 
 
TUP171 Influence of Proton Irradiation on Angular Dependence of Second Generation (2G) HTS radiation, quadrupole, target, superconductivity 1145
 
  • Y. Shiroyanagi, G.A. Greene, R.C. Gupta, W. Sampson
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by the U.S. DOE under Contract No. DE-AC02-98CH10886 and under Cooperative Agreement DE-SC0000661 from DOE-SC that provides financial assistance to MSU to design and establish FRIB.
In the Facility for Rare Isotope Beams (FRIB), superconducting magnets will be exposed to high levels of ionizing radiation. Quadruples in the fragment separator will be exposed to radiation doses as high as ~20 MGy/yr and heat loads as high as ~10 kW/m. High temperature superconducting (HTS) tapes are good candidates for this magnet because they can be operated in the temperature range ~30-50 K to tolerate higher temperatures than low temperature superconductors. Thus, radiation damage studies of HTS tapes are crucial to ensure that they will perform satisfactorily in such a high radiation environment. Therefore, the effects of proton irradiation on second generation HTS tapes from two vendors were studied. Each sample of HTS tape from SuperPower and American Superconductor was irradiated by a 42μA, 142 MeV proton beam at the Brookhaven Linac Isotope Producer. Two of each were irradiated at 5 dose levels: 2.5, 25, 50, 75 and 100μA•hr. The angular dependence of the critical current was measured in a magnetic field at 77K. Based on these measurements, conductors from both vendors appear to satisfy the FRIB radiation-tolerance requirement of 10 years of operation.
 
 
TUP202 Non-Scaling FFAG Proton Driver for Project X linac, injection, focusing, synchrotron 1199
 
  • C. Johnstone, D.V. Neuffer
    Fermilab, Batavia, USA
  • M. Berz, K. Makino
    MSU, East Lansing, Michigan, USA
  • L.J. Jenner, J. Pasternak
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • P. Snopok
    IIT, Chicago, Illinois, USA
 
  The next generation of high-energy physics experiments requires high intensity protons at multi-GeV energies. Fermilab’s HEP program, for example, requires an 8-GeV proton source to feed the Main Injector to create a 2 MW neutrino beams in the near term and would require a 4 MW pulsed proton beam for a potential Neutrino Factory or Muon Collider in the future. High intensity GeV proton drivers are difficult at best with conventional re-circulating accelerators, encountering duty cycle and space-charge limits in the synchrotron and machine size and stability concerns in the weaker-focusing cyclotrons. Only an SRF linac, which has the highest associated cost and footprint, has been considered. Recent innovations in FFAG design, however, have promoted another re-circulating candidate, the Fixed-field Alternating Gradient accelerator (FFAG), as an attractive, but as yet unexplored, alternative. Its strong focusing optics coupled to large transverse and longitudinal acceptances would serve to alleviate space charge effects and achieve higher bunch charges than possible in a synchrotron and presents an upgradeable option from the 2 MW to the 4 MW program.  
 
TUP207 The Effects of the RHIC E-lenses Magnetic Structure Layout on the Proton Beam Trajectory electron, lattice, closed-orbit, solenoid 1202
 
  • X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed in RHIC IR10. First, the layout of these two E-lenses is introduced. Then the effects of e-lenses on proton beam are discussed. For example, the transverse fields of the e-lens bending solenoids and the fringe field of the main solenoids will shift the proton beam. For the effects of the e-lens on proton beam trajectory, we calculate the transverse kicks that the proton beam receives in the electron lens via Opera at first. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.
 
 
TUP265 A Solenoid Capture System for a Muon Collider target, factory, collider, solenoid 1316
 
  • H.G. Kirk, R.C. Fernow, N. Souchlas
    BNL, Upton, Long Island, New York, USA
  • J.J. Back
    University of Warwick, Coventry, United Kingdom
  • C.J. Densham, P. Loveridge
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • X.P. Ding
    UCLA, Los Angeles, California, USA
  • V.B. Graves
    ORNL, Oak Ridge, Tennessee, USA
  • T. Guo, F. Ladeinde, V. Samulyak, Y. Zhan
    SUNY SB, Stony Brok, New York, USA
  • K.T. McDonald
    PU, Princeton, New Jersey, USA
  • R.J. Weggel
    Particle Beam Lasers, Inc., Northridge, California, USA
 
  Funding: This work was supported in part by the US DOE Contract No. DE-AC02-98CH10886.
The concept for a muon-production system for a muon collider or neutrino factory calls for an intense 4-MW-class proton beam impinging upon a free-flowing mercury jet immersed in a 20-T solenoid field. This system is challenging in many aspects, including magnetohydrodynamics of the mercury jet subject to disruption by the proton beam, strong intermagnetic forces, and the intense thermal loads and substantial radiation damage to the magnet coils due to secondary particles from the target. Studies of these issues are ongoing, with a sketch of their present status given here.
 
 
TUP282 The MICE Target target, acceleration, extraction, injection 1355
 
  • P.J. Smith, C.N. Booth, P. Hodgson, E. Overton, M. Robinson
    Sheffield University, Sheffield, United Kingdom
  • G.J. Barber, K.R. Long
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
  • E.G. Capocci, J.S. Tarrant
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • B.J.A. Shepherd
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  The MICE experiment uses a beam of low energy muons to test the feasibility of ionization cooling. This beam is derived parasitically from the ISIS accelerator at the Rutherford Appleton Laboratory. A target mechanism has been developed and deployed that rapidly inserts a small titanium target into the circulating proton beam immediately prior to extraction without undue disturbance of the primary ISIS beam. The first target drive was installed in ISIS during 2008 and operated successfully for over 100,000 pulses. A second upgraded design was installed in 2009 and after more than half a million actuations is still in operation. Further upgrades to the target design are now being tried in a separate test rig at the Rutherford Appleton Laboratory. The technical specifications for these upgraded designs are given and the motivations for the improvements are discussed. Additionally, further future improvements to the current design are discussed.  
 
TUP284 AGS Tune Jump System to Cross Horizontal Depolarization Resonances Overview resonance, controls, power-supply, polarization 1361
 
  • J.W. Glenn, L. A. Ahrens, Z. Altinbas, W. Fu, J.-L. Mi, P.J. Rosas, V. Schoefer, C. Theisen
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Two partial snakes overcome the vertical depolarizing resonances in the AGS. But a new type of depolarizing intrinsic resonance from horizontal motion appeared. We reduce these using horizontal tune jumps timed to these resonances. We gain a factor of five in crossing rate with a tune jump of 0.04 in 100 micro-sec. Two quadrapoles, we described in 2009 *, pulse 42 times, the current matching beam energy. The power supplies for these quads will be described in this conference**. The controls for the Jump Quad system is based on a BNL designed Quad Function Generator. Two modules are used; one for timing, and one to supply reference voltages. Synchronization is provided by a proprietary serial bus, the Event Link. The AgsTuneJump application predicts the times of the resonances during the AGS cycle and calculates the power supply trigger times from externally collected tune and energy verses time data and the Low and High PS voltage functions from a voltage to current model of the power supply. The system was commissioned during runs 09 & 10. Beam effects are described elsewhere in this conference***. Details of improvements, operation and the feed forward software will be described.
* JW Glenn, et al “AGS Fast Spin Resonance,-” PAC-09
** JL Mi, et al “AGS Tune Jump Power-” these proceedings
*** L.A.Ahrens, et al "Recent RHIC Motivated Polarized-" these proceedings
 
 
TUP288 A Very Thin Havar Film Vacuum Window for Heavy Ions to Perform Radiobiology Studies at the BNL Tandem ion, vacuum, heavy-ion, light-ion 1367
 
  • P. Thieberger, H. Abendroth, J.G. Alessi, L. Cannizzo, C. Carlson, A. Gustavsson, M.G. Minty, L. Snydstrup
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Heavy ion beams from one of the BNL Tandem Van de Graaff accelerators will be made available for radiobiology studies on cell cultures. Energy losses need to be minimized both in the vacuum window and in the air in order to achieve the ranges required for the cells to be studied. This is particularly challenging for ions heavier than iron. The design is presented of a 0.4” diameter Havar film window that will satisfy these requirements. Films as thin as 80μinches were successfully pressure tested. The final thickness to be used may be slightly larger to help in achieving pin hole free windows. We discuss design considerations and present pressure and vacuum test results as well as tests with heavy ion beams.
 
 
WEOBN6 LARP LHC 4.8 GHz Schottky System Initial Commissioning with Beam pick-up, controls, injection, ion 1413
 
  • R.J. Pasquinelli
    Fermilab, Batavia, USA
  • F. Caspers, O.R. Jones
    CERN, Geneva, Switzerland
  • A. Jansson
    ESS, Lund, Sweden
 
  The LHC Schottky system consists for four independent 4.8 GHz triple down conversion receivers with associated data acquisition systems. Each system is capable of measuring tune, chromaticity, momentum spread in either horizontal or vertical planes; two systems per beam. The hardware commissioning has taken place during the spring and summer of 2010. With nominal bunch beam currents of 1011 protons, the first incoherent Schottky signals were detected and analyzed. This paper will report on these initial commissioning results. A companion paper will report on the data analysis curve fitting and remote control user interface of the system.  
slides icon Slides WEOBN6 [27.117 MB]  
 
WEOBS6 Status and Specifications of a Project X Front-End Accelerator Test Facility at Fermilab cavity, rfq, linac, ion-source 1430
 
  • J. Steimel, R.L. Madrak, R.J. Pasquinelli, E. Peoples-Evans, R.C. Webber, D. Wildman
    Fermilab, Batavia, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
This paper describes the construction and operational status of an accelerator test facility for Project X. The purpose of this facility is for Project X component development activities that benefit from beam tests and any development activities that require 325 MHz or 650 MHz RF power. It presently includes an H- beam line, a 325 MHz superconducting cavity test facility, a 325 MHz (pulsed) RF power source, and a 650 MHz (CW) RF power source. The paper also discusses some specific Project X components that will be tested in the facility.
 
slides icon Slides WEOBS6 [2.401 MB]  
 
WEOCN2 A Non-Destructive Profile Monitor for High Intensity Beams electron, gun, quadrupole, controls 1438
 
  • W. Blokland, S.M. Cousineau
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
A non-destructive profile monitor has been installed and commissioned in the accumulator ring of the Spallation Neutron Source (SNS). The SNS Ring accumulates high intensity proton bunches of up to 1.5·1014 protons with a typical peak current of over 50 A and a bunch length of about 0.7 us during a 1 ms cycle. The profile monitor consists of two systems, one for each plane, with electron guns, correctors, defectors, and quadrupoles to produce pulsed electron beams that scan through the proton bunch. The proton bunch EM fields alter the trajectory of the electrons and their projection on a fluorescent screen. The projection is analyzed to determine the transverse profile of the proton bunch. The speaker will describe the theory, hardware, software, analysis, results, and improvements to these electron scanners. The results include a comparison to wire scanner profiles of extracted ring beam.
 
slides icon Slides WEOCN2 [9.476 MB]  
 
WEOCN3 Operational Results from the LHC Luminosity Monitors luminosity, ion, simulation, target 1443
 
  • R. Miyamoto
    BNL, Upton, Long Island, New York, USA
  • E. Bravin
    CERN, Geneva, Switzerland
  • H.S. Matis, A. Ratti, W.C. Turner, H. Yaver, T. stezelberger
    LBNL, Berkeley, California, USA
 
  Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP).
The Luminosity Monitors for the high luminosity regions in the LHC have been operating to monitor and optimize the luminosity since the beginning of the 2009 run. The device is a gas ionization chamber, which has the ability to resolve bunch-by-bunch luminosity as well as survive the extreme levels of radiation at nominal high intensity LHC operations. The chambers are installed at the zero degree collision angle inside the neutral absorbers 140 m from the interaction point and monitor showers produced by high energy neutral particles from the collisions. A second device, a photo-multiplier based system (PMT) located directly behind the gas ionization chamber, has been also used at low luminosities. We will present operational results for the ionization chambers for both pp and Pb-Pb collisions. These measurements include signal, noise and background studies, and correlation between the gas ionization detector and the PMT. Also, comparison with ongoing modeling efforts will be included.
 
slides icon Slides WEOCN3 [2.609 MB]  
 
WEODS2 High-Power Targets: Experience and R&D for 2 MW target, radiation, neutron, simulation 1496
 
  • P. Hurh
    Fermilab, Batavia, USA
  • O. Caretta, T.R. Davenne, C.J. Densham, P. Loveridge
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • N. Simos
    BNL, Upton, Long Island, New York, USA
 
  High-power particle production targets are crucial elements of future neutrino and other rare particle beams. Fermilab plans to produce a beam of neutrinos (LBNE) with a 2.3 MW proton beam (Project X). Any solid target is unlikely to survive for an extended period in such an environment - many materials would not survive a single beam pulse. We are using our experience with previous neutrino and antiproton production targets, along with a new series of R&D tests, to design a target that has adequate survivability for this beamline. The issues considered are thermal shock (stress waves), heat removal, radiation damage, radiation accelerated corrosion effects, physics/geometry optimization and residual radiation.  
 
WEP007 Calculation of Acceptance of High Intensity Superconducting Proton Linac for Project-X linac, cavity, lattice, focusing 1516
 
  • A. Saini, K. Ranjan
    University of Delhi, Delhi, India
  • C.S. Mishra, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  Project-X is the proposed high intensity proton facility to be built at Fermilab, US. Its Superconducting Linac, to be used at first stage of acceleration, will be operated in continuous wave (CW) mode. The Linac is divided into three sections on the basis of operating frequencies & six sections on the basis of family of RF cavities to be used for the acceleration of beam from 2.5 MeV to 3 GeV. The transition from one section to another can limit the acceptance of the Linac if these are not matched properly. We performed a study to calculate the acceptance of the Linac in both longitudinal and transverse plane. Investigation of most sensitive area which limits longitudinal acceptance and study of influence of failure of beam line elements at critical position, on acceptance are also performed.  
 
WEP016 Evaluating the Dynamic Aperture for the New RHIC 250-GeV Polarized Proton Lattice dynamic-aperture, lattice, emittance, luminosity 1528
 
  • X. Gu, W. Fischer, H. Huang, Y. Luo, S. Tepikian
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
To increase luminosity in the Relativistic Heavy Ion Collider’s (RHIC’s) polarized proton 250 GeV operations, we are considering reducing beta* to 0.65 m at the interaction points (IPs), and increasing bunch intensity. The new working point near the 2/3 integer will used on the ramp to preserve polarization. In addition, we plan to adjust the betatron-phase advances between IP6 and IP8 to (k+1/2)*PI so to lower the dynamic beta-beat from the beam-beam interaction. The effects of all these changes will impact the dynamic aperture, and hence, it must be evaluated carefully. In this article, we present the results of tracking the dynamic aperture with the proposed lattices.
 
 
WEP032 Beam Transport in a Compact Dielectric Wall Accelerator for Proton Therapy beam-transport, accelerating-gradient, emittance, focusing 1552
 
  • Y.-J. Chen, D.T. Blackfield, G.J. Caporaso, S.D. Nelson, B. R. Poole
    LLNL, Livermore, California, USA
 
  Funding: This work performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA2A27344.
To attain the highest accelerating gradient in the compact dielectric wall (DWA) accelerator, the accelerating voltage pulses should have the shortest possible duration. To do so, the DWA will be operated in the “virtual” traveling mode*. Since only a short section of HGI wall would be excited, the accelerating field’s axial profile could be non-uniform and time dependent, especially near the entrance and exit of the DWA, which could lead to dispersion in beam acceleration and transport, and eventually emittance growth. The dispersive transverse kick on a short proton bunch at the DWA entrance and its impact on acceptable input proton bunch length will be discussed. Without using any external lenses, the dispersive transverse kicks on the beam can be mitigated. Implementing the mitigations into the transport strategy, we have established a baseline transport case. Results of simulations using 3-D, EM PIC code, LSP** indicate that the DWA transport performance meets the medical specifications for intensity modulation proton treatment. Sensitivity of the transport performance to the switch timing will be presented.
* G. J. Caporaso, Y-J Chen and S. E. Sampayan, "The Dielectric Wall Accelerator", Rev. of Accelerator Science and Technology, vol. 2, p. 253 (2009).
** Alliant Techsystems Inc., http://www.lspsuite.com/.
 
 
WEP039 Tracking Stripped Proton Particles in SNS Ring Injection Momentum Dump Line dipole, simulation, collimation, injection 1567
 
  • J. G. Wang
    ORNL, Oak Ridge, Tennessee, USA
 
  3D computer simulations are performed to study magnetic field distributions and particle trajectories along the SNS ring injection momentum dump line. Optical properties and transfer maps along the dump line are calculated. The stripped proton particle distributions on the dump window are analyzed. The study has provided useful information for the redesign of the SNS ring injection beam dump.  
 
WEP045 Measurement and Manipulation of Beta Functions in the Fermilab Booster booster, coupling, quadrupole, acceleration 1579
 
  • M.J. McAteer, S.E. Kopp
    The University of Texas at Austin, Austin, Texas, USA
  • E. Prebys
    Fermilab, Batavia, USA
 
  In order to meet the needs of Fermilab’s planned post- collider experimental program, the total proton throughput of the 8 GeV Booster accelerator must be nearly doubled within the next two years. A system of 48 ramped corrector magnets has recently been installed in the Booster to help improve efficiency and allow for higher beam intensity without exceeding safe radiation levels. We present the preliminary results of beta function measurements made using these corrector magnets. Our goal is to use the correctors to reduce irregularities in the beta function, and ultimately to introduce localized beta bumps to reduce beam loss or direct losses towards collimators.  
 
WEP079 Mathematical Models of Feedback Systems for Control of Intra-Bunch Instabilities Driven by E-Clouds and TMCI feedback, electron, controls, simulation 1621
 
  • C.H. Rivetta, J.D. Fox, T. Mastoridis, M.T.F. Pivi, O. Turgut
    SLAC, Menlo Park, California, USA
  • W. Höfle
    CERN, Geneva, Switzerland
  • R. Secondo, J.-L. Vay
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
The feedback control of intrabunch instabilities driven by E-Clouds or strong head-tail coupling (TMCI) requires sufficient bandwidth to sense the vertical position and drive multiple sections of a nanosecond scale bunch. These requirements impose challenges and limits in the design and implementation of the feedback system. This paper presents models for the feedback subsystems: receiver, processing channel, amplifier and kicker, that take into account their frequency response and limits. These models are included in multiparticle simulation codes (WARP/CMAD/Head-Tail) and reduced mathematical models of the bunch dynamics to evaluate the impact of subsystem limitations in the bunch stabilization and emittance improvement. With this realistic model of the hardware, it is possible to analyze and design the feedback system. This research is crucial to evaluate the performance boundary of the feedback control system due to cost and technological limitations. These models define the impact of spurious perturbations, noise and parameter variations or mismatching in the performance of the feedback system. The models are validated with simulation codes and measurements of lab prototypes.
 
 
WEP082 Crab Crossing Consideration for MEIC cavity, electron, emittance, betatron 1627
 
  • S. Ahmed, Y.S. Derbenev, G.A. Krafft, Y. Zhang
    JLAB, Newport News, Virginia, USA
  • A. Castilla, J.R. Delayen, S.D. Silva
    ODU, Norfolk, Virginia, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Crab crossing of colliding electron and ion beams is essential for accommodating the ultra high bunch repetition frequency in the conceptual design of MEIC – a high luminosity polarized electron-ion collider at Jefferson Lab. The scheme eliminates parasitic beam-beam interactions and avoids luminosity reduction by restoring head-on collisions at interaction points. In this paper, we report simulation studies of beam dynamics with crab cavities for MEIC design. The detailed study involves full 3-D simulations of particle tracking through the various configurations of crab cavities for evaluating the performance. To gain insight, beam and RF dominated fields with other parametric studies will be presented in the paper.
 
 
WEP091 Implementation of H Intrabeam Stripping into TRACK linac, simulation, ion, beam-losses 1642
 
  • J.-P. Carneiro
    Fermilab, Batavia, USA
  • B. Mustapha, P.N. Ostroumov
    ANL, Argonne, USA
 
  H intrabeam stripping has been presented* as potentially harmful to MW scale H linacs. If not taken properly into account, intrabeam stripping of the H beam could lead to losses in excess of the 1 W/m limit and result in non-tolerable beamline elements activation. This paper describes the implementation of the H intrabeam stripping effect into the beam dynamics code TRACK**. Simulations results and numerical applications will be presented for the SNS linac and the FNAL ProjectX.
* V. Lebedev, "Intrabeam Stripping in H Linacs", LINAC2010
** P. Ostroumov, "TRACK, The Beam Dynamics Code", PAC2005
 
 
WEP094 Space Charge Measurements with a High Intensity Bunch at the Fermilab Main Injector simulation, emittance, space-charge, injection 1648
 
  • K. Seiya, B. Chase, J.E. Dey, P.W. Joireman, I. Kourbanis
    Fermilab, Batavia, USA
  • A. Yagodnitsyna
    NSU, Novosibirsk, Russia
 
  Fermilab Main Injector will be required to operate with 3 times higher bunch intensity than today for Project X. The plan to study the space charge effects at the injection energy with intense bunches will be discussed.  
 
WEP096 Simulations of Space Charge in the Fermilab Main Injector space-charge, emittance, simulation, lattice 1654
 
  • E.G. Stern, J.F. Amundson, P. Spentzouris
    Fermilab, Batavia, USA
  • J. Qiang, R.D. Ryne
    LBNL, Berkeley, California, USA
 
  The Fermilab Project X plan for future high intensity running relies on the Main Injector as the engine for delivering protons in the 60-120 GeV energy range. Project X plans call for increasing the number of protons per Main Injector bunch from the current value of 1.0× 1011 to 3.0× 1011. Space charge effects at the injection energy of 8 GeV have the potential to seriously disrupt operations. We report on ongoing simulations with Synergia, our multi-physics process accelerator modeling framework, to model space charge effects in the Main Injector combined with the effects of magnet fringe fields and apertures.  
 
WEP112 Accurate Simulation of the Electron Cloud in the Fermilab Main Injector with VORPAL electron, simulation, dipole, quadrupole 1692
 
  • P. Lebrun, P. Spentzouris
    Fermilab, Batavia, USA
  • J.R. Cary, P. Stolz, S.A. Veitzer
    Tech-X, Boulder, Colorado, USA
 
  Precision simulations of the electron cloud at the Fermilab Main Injector (MI) have been studied using the plasma simulation code VORPAL. Fully 3D and self consistent solutions that includes Yee-type E.M. field maps, electron spatial distributions and the time evolution of the cloud with respect to the bunch structure in the MI. The microwave absorption experiment has been simulated in detail and the response of the antennas has been derived from the VORPAL's pseudo-potential data. Based on the results of these simulations and the ongoing experimental program, two distinct new experimental techniques are proposed. The first one is based on the use BPM plates placed in dipole fields and that are made of material(s) for which the secondary emission is well characterized. The second technique would be based on the optical, or ultra-violet, detection of the radiation emitted (inverse photo-electric effect) when the cloud interacts with the inner surface of the beam pipe. As the microwave absorption experiment, this techique is non-invasise and has the advantage of providing spatial images of the cloud as well as accurate timing (ns) information.  
 
WEP125 Higher-order Spin Resonances in 2.1 GeV/c Polarized Proton Beam resonance, polarization, injection, betatron 1716
 
  • M.A. Leonova, J. Askari, K.N. Gordon, A.D. Krisch, J. Liu, D.A. Nees, R.S. Raymond, D.W. Sivers, V.K. Wong
    University of Michigan, Spin Physics Center, Ann Arbor, MI, USA
  • F. Hinterberger
    Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, Bonn, Germany
  • V.S. Morozov
    JLAB, Newport News, Virginia, USA
 
  Funding: This research was supported by grants from the German Science Ministry
Spin resonances can cause partial or full depolarization or spin-flip of a polarized beam. We studied 1st-, 2nd- and 3rd-order spin resonances with a 2.1 GeV/c vertically polarized proton beam stored in the COSY Cooler Synchrotron. We observed almost full spin-flip when crossing the 1st-order G*gamma=8−nuy vertical-betatron-tune spin resonance and partial depolarization near some 2nd- and 3rd-order resonances. We observed almost full depolarization near the 1st-order G*gamma=8−nux horizontal spin resonance and partial depolarization near some 2nd- and 3rd-order resonances. Moreover, we found that a 2nd-order nux resonance seems about as strong as some 3rd-order nux resonances, while some 3rd-order nuy resonances seem much stronger than a 2nd-order nuy resonance. It was thought that, for flat accelerators, vertical spin resonances are stronger than horizontal, and lower order resonances are stronger than higher order ones. The data suggest that many higher-order spin resonances, both horizontal and vertical, must be overcome to accelerate polarized protons to high energies; the data may help RHIC to better overcome its snake resonances between 100 and 250 GeV/c.
 
 
WEP154 Direct Numerical Modeling of E-Cloud Driven Instability of a Bunch Train in the CERN SPS electron, simulation, feedback, emittance 1776
 
  • J.-L. Vay, M.A. Furman, M. Venturini
    LBNL, Berkeley, California, USA
 
  Funding: Supported by the US-DOE under Contract DE-AC02-05CH11231, the SciDAC program ComPASS and the US-LHC Accelerator Research Program (LARP). Used resources of NERSC and the Lawrencium cluster at LBNL.
Electron clouds impose limitations on current accelerators that may be more severe for future machines, unless adequate measures of mitigation are taken. It has been proposed recently to use feedback systems operating in the GHz range to damp single-bunch transverse coherent electron cloud driven instabilities that may occur in relatively long, ns scale, proton bunches such as those in the CERN SPS. The simulation package WARP-POSINST was recently upgraded for handling multiple bunches and modeling concurrently the electron cloud buildup and its effect on the beam, allowing for direct self-consistent simulation of bunch trains generating, and interacting with, electron clouds. We have used the WARP-POSINST package on massively parallel supercomputers to study the growth rate and frequency patterns in space-time of the electron cloud driven transverse instability for a proton bunch train in the CERN SPS accelerator with, or without, feedback models (with various levels of idealization) for damping the instability. We will present our latest simulation results, contrast them with actual measurements and discuss the implications for the design of the actual feedback system.
 
 
WEP204 An FFAG Accelerator for Project X lattice, linac, injection, dynamic-aperture 1867
 
  • D.V. Neuffer, L.J. Jenner, C. Johnstone
    Fermilab, Batavia, USA
  • J. Pasternak
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
 
  The next generation of high-energy physics experiments requires high intensity protons in the multi-GeV energy range for efficient production of secondary beams. The Fermilab long-term future requires an 8 GeV proton source to feed the Main Injector for a 2 MW neutrino beam source in the immediate future and to provide 4 MW pulsed proton beam for a future neutrino factory or muon collider. We note that a 3GeV cw linac matched to a 3–8 GeV FFAG ring could provide beam for both of these mission needs, as well as the cw 3 GeV experiments, and would be a natural and affordable scenario. We present details of possible scenarios and outline future design and research directions.  
 
WEP206 An Accumulator/Pre-Booster for the Medium-Energy Electron Ion Collider at JLab booster, ion, emittance, injection 1873
 
  • B. Erdelyi, S. Abeyratne
    Northern Illinois University, DeKalb, Illinois, USA
  • Y.S. Derbenev, G.A. Krafft, Y. Zhang
    JLAB, Newport News, Virginia, USA
  • S.L. Manikonda, P.N. Ostroumov
    ANL, Argonne, USA
 
  Future nuclear physics facilities such as the proposed electron ion collider (MEIC) will need to achieve record high luminosities in order to maximize discovery potential. Among the necessary ingredients is the ability to generate, accumulate, accelerate, and store high current ion beams from protons to lead ions. One of the main components of this ion accelerator complex for MEIC chain is the accumulator that also doubles as a pre-booster, which takes 200 MeV protons from a superconducting linear accelerator, accumulates on the order of 1A beam, and boosts its energy to 3GeV, before extraction to the next accelerator in the chain, the large booster. This paper describes its design concepts, and summarizes some preliminary results, including linear optics, space charge dynamics, and spin polarization resonance analysis.  
 
WEP207 Progress Towards A Novel Compact High Voltage Electrostatic Accelerator high-voltage, vacuum, tandem-accelerator, injection 1876
 
  • P. Beasley, O. Heid
    Siemens AG, Healthcare Technology and Concepts, Erlangen, Germany
 
  A proof-of-principle demonstrator system has been successfully built and tested. It is based on a Cockcroft-Walton (or Greinacher) cascade but has been developed using a different design philosophy and using modern materials. This can then enable this compact accelerator configuration to operate at much higher voltage gradients. This paper explores the progress made to-date and future plans to utilize the technology to develop one such concept for an energy efficient 10 MV, 100 microamp, tandem proton accelerator, with less than a 2 square meter footprint .  
 
WEP221 CW Room-Temperature Bunching Cavity for the Project X MEBT cavity, linac, simulation, bunching 1900
 
  • G.V. Romanov, S. Barbanotti, E. Borissov, J.A. Coghill, I.G. Gonin, S. Kazakov, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  The Project-X, a multi-MW proton source based on superconducting linac, is under development at Fermilab. The front end of the linac contains a CW room temperature MEBT section which comprises ion source, RFQ and high-bandwidth bunch selective chopper. The length of the chopper exceeds 10 m, so four re-bunching cavities are used to support the beam longitudinal dynamics. The RF and mechanical designs of the re-bunching cavity including stress and thermal analysis are reported.  
 
WEP224 Operational Status and Life Extension Plans for the Los Alamos Neutron Science Center (LANSCE) neutron, linac, target, scattering 1906
 
  • J.L. Erickson, D. Rees
    LANL, Los Alamos, New Mexico, USA
 
  Funding: Work supported by the U. S. Department of Energy, National Nuclear Security Administration, Contract No. DE-AC52-06NA25396 – Publication Release LA-UR- 10-06556
The Los Alamos Neutron Science Center (LANSCE) accelerator and beam delivery complex generates the proton beams that serve three neutron production sources, a proton radiography facility and a medical and research isotope production facility. The recent operating history of the facility, including both achievements and challenges, will be reviewed. Plans for performance improvement will be discussed, together with the underlying drivers for the ongoing LANSCE Linac Risk Mitigation project. The details of this latter project will be discussed. The status of accelerator-related plans for the MaRIE Project (Matter-Radiation Interactions in Extremes Experimental Project) will also be discussed. Taken together, the LANSCE Linac Risk Mitigation Project and the MaRIE initiative demonstrate a commitment to investment in the ongoing operation and improvement of the facility, and a resurgent interest in the spectrum of science accessible at LANSCE. These plans will assure continued facility operational and scientific vitality well beyond 2020.
 
 
WEP229 Status of 2 MeV Electron Cooler for COSY-Julich/HESR electron, high-voltage, antiproton, solenoid 1918
 
  • J. Dietrich, V. Kamerdzhiev
    FZJ, Jülich, Germany
  • M.I. Bryzgunov, A.D. Goncharov, V.M. Panasyuk, V.V. Parkhomchuk, V.B. Reva, D.N. Skorobogatov
    BINP SB RAS, Novosibirsk, Russia
 
  The 2 MeV electron cooling system for COSY-Jülich was proposed to further boost the luminosity even in presence of strong heating effects of high-density internal targets. The 2 MeV cooler is also well suited in the start up phase of the High Energy Storage Ring (HESR) at FAIR in Darmstadt. It can be used for beam cooling at injection energy and is intended to test new features of the high energy electron cooler for HESR. The project is funded since mid 2009. The design and construction of the cooler is accomplished in cooperation with the Budker Institute of Nuclear Physics in Novosibirsk, Russia. The technical layout of the 2 MeV electron cooler is described. The infrastructure necessary for the operation of the cooler in the COSY ring (radiation shielding, cabling, water cooling etc.) is established. The electron beam commissioning at BINP Novosibirsk is scheduled to start at the end of 2010. First results are reported.  
 
WEP232 A Multi Megawatt Ring Cyclotron to Search for CP Violation in the Neutrino Sector extraction, cyclotron, injection, cavity 1924
 
  • L. Calabretta, M.M. Maggiore, D. Rifuggiato
    INFN/LNS, Catania, Italy
  • A. Calanna
    CSFNSM, Catania, Italy
  • L.A.C. Piazza
    INFN/LNL, Legnaro (PD), Italy
 
  A new approach to search for CP violation in the neutrino sector* is proposed by the experiment called DAEδALUS (Decay At rest Experiment for cp At Laboratory for Underground Science). DAEδALUS needs three sources of neutrino fluxes, each one located at 1.5, 8 and 20 km from the underground detector. Each source has to be supplied with a proton beam with power higher than 1, 2 and 5 MW respectively. Here we present the study for a Superconducting Ring Cyclotron able to accelerate the H2+ molecules and to deliver proton beam with maximum energy of 800 MeV and the required power. Although the average power for the first 2 sites are 1 and 2 MW, the 20% duty cycle, required by the experiment, has the consequence that the peak power should stay in the range 5-10 MW and a peak current of about 4.5 mA of H2+ is necessary. We present the parameters of the superconducting magnetic sector simulated by the code TOSCA, the isochronous magnetic field produced and the magnetic forces acting on the coils. Some evaluation on the feasibility of the ring cyclotron, the advantages and problems relates with acceleration of the H2+ molecules will be also presented.
* J. Alonso et al., “Expression of Interest for a Novel Search for CP Violation in the Neutrino Sector: DAEδALUS”, Jun 2010. e-Print: arXiv:1006.0260
 
 
WEP242 Project X Functional Requirements Specification linac, injection, collider, kaon 1936
 
  • S.D. Holmes, S. Henderson, R.D. Kephart, J.S. Kerby, C.S. Mishra, S. Nagaitsev, R.S. Tschirhart
    Fermilab, Batavia, USA
 
  Funding: Work supported by the Fermi Research Alliance, under contract to the U.S. Department of Energy
Project X is a multi-megawatt proton facility being designed to support intensity frontier research in elementary particle physics, with possible applications to nuclear physics and nuclear energy research, at Fermilab. A Functional Requirements Specification has been developed in order to establish performance criteria for the Project X complex in support of these multiple missions. This paper will describe the Functional Requirements for the Project X facility and the rationale for these requirements.
 
 
WEP248 Overview of the LBNE Neutrino Beam target, simulation, remote-handling, shielding 1948
 
  • C.D. Moore, Y. He, P. Hurh, J. Hylen, B.G. Lundberg, M.W. McGee, J.R. Misek, N.V. Mokhov, V. Papadimitriou, R.K. Plunkett, R.P. Schultz, G. Velev, K.E. Williams, R.M. Zwaska
    Fermilab, Batavia, USA
 
  Funding: Work supported by Fermi Research Alliance, LLC, under contract DE-AC02-07CH11359 with the U.S. Department of Energy.
The Long Baseline Neutrino Experiment (LBNE) will utilize a neutrino beamline facility located at Fermilab. The facility will aim a beam of neutrinos toward a detector placed at the Deep Underground Science and Engineering Laboratory (DUSEL) in South Dakota. The neutrinos are produced in a three step process. First, protons from the Main Injector hit a solid target and produce mesons. Then, the charged mesons are focused by a set of focusing horns into the decay pipe, towards the far detector. Finally, the mesons that enter the decay pipe decay into neutrinos. The parameters of the facility were determined by an amalgam of the physics goals, the Monte Carlo modeling of the facility, and the experience gained by operating the NuMI facility at Fermilab. The initial beam power is expected to be ~700 kW, however some of the parameters were chosen to be able to deal with a beam power of 2.3 MW.
 
 
WEP249 Intense Muon Beams for Experiments at Project X target, simulation, collider, linac 1951
 
  • C.M. Ankenbrandt, R.P. Johnson, C. Y. Yoshikawa
    Muons, Inc, Batavia, USA
  • V.S. Kashikhin, D.V. Neuffer
    Fermilab, Batavia, USA
  • J. Miller
    BUphy, Boston, Massachusetts, USA
  • R.A. Rimmer
    JLAB, Newport News, Virginia, USA
 
  Funding: Supported in part by DOE SBIR grant DE-SC00002739
A coherent approach for providing muon beams to several experiments for the intensity-frontier program at Project X is described. Concepts developed for the front end of a muon collider/neutrino factory facility, such as phase rotation and ionization cooling, are applied, but with significant differences. High-intensity experiments typically require high-duty-factor beams pulsed at a time interval commensurate with the muon lifetime. It is challenging to provide large RF voltages at high duty factor, especially in the presence of intense radiation and strong magnetic fields, which may preclude the use of superconducting RF cavities. As an alternative, cavities made of materials such as ultra-pure Al and Be, which become very good - but not super - conductors at cryogenic temperatures, can be used.
 
 
WEP256 Laser-Proton Acceleration as Compact Ion Source laser, simulation, solenoid, electron 1960
 
  • S. Busold, O. Deppert, K. Harres, G. Hoffmeister, F. Nürnberg, M. Roth
    TU Darmstadt, Darmstadt, Germany
  • A. Almomani, C. Brabetz, M. Droba, O.K. Kester, U. Ratzinger
    IAP, Frankfurt am Main, Germany
  • V. Bagnoud, W.A. Barth, A. Blazevic, O. Boine-Frankenheim, P. Forck, I. Hofmann, A. Orzhekhovskaya, T. Stöhlker, A. Tauschwitz, W. Vinzenz, S.G. Yaramyshev
    GSI, Darmstadt, Germany
  • T.J. Burris-Mog, T.E. Cowan
    HZDR, Dresden, Germany
  • A. Gopal, S. Herzer, O. Jäckel, B. Zielbauer
    HIJ, Jena, Germany
  • T. Herrmannsdoerfer, M. Joost
    FZD, Dresden, Germany
  • M. Kaluza
    IOQ, Jena, Germany
 
  Preparatory work is presented in the context of the upcoming LIGHT project, which is dedicated to build up a test stand for injecting laser accelerated protons into conventional accelerator structures, located at GSI Helmholtzcenter for Heavy Ion Research (Darmstadt, Germany). In an experimental campaign in 2010, a beam of 8.4×109 protons with 170 ps pulse duration and (6.7±0.1) MeV particle energy could be focused with the use of a pulsed high-field solenoid. Collimation and transport of a 300 ps proton bunch containing 3×109 protons with (13.5±0.5) MeV particle energy over a distance of 407 mm was also demonstrated. Parallel simulation studies of the beam transport through the solenoid are in good agreement with the experiment.  
 
WEP267 Estimates of the Number of Foil Hits for Charge Exchange Injection injection, linac, ion, betatron 1975
 
  • D. Raparia
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
For high intensity circular proton machines, one of the major limitations is the charge exchange injection foil. The number of foil hits due to circulating beam may cause the foil to fail and cause radiation due to multiple nuclear scattering and energy straggling. This paper will describe methods to estimate these quantities without going through lengthy simulations.
 
 
WEP297 A Conceptual Design of the 2+ MW LBNE Beam Absorber simulation, shielding, target, hadron 2041
 
  • G. Velev, S.C. Childress, P. Hurh, J. Hylen, A.V. Makarov, N.V. Mokhov, C.D. Moore, I. Novitski
    Fermilab, Batavia, USA
 
  Funding: This work is supported by the U.S. Department of Energy.
The Long Baseline Neutrino Experiment (LBNE) will utilize a neutrino beamline facility located at Fermilab. The facility will aim a beam of neutrinos, produced by 60-120 GeV protons from the Fermilab Main Injector, toward a detector placed at the Deep Underground Science and Engineering Laboratory (DUSEL) in South Dakota. Secondary particles that do not decay into muons and neutrinos as well as any residual proton beam must be stopped at the end of the decay region to reduce noise/damage in the downstream muon monitors and reduce activation in the surrounding rock. This goal is achieved by placing an absorber structure at the end of the decay region. The requirements and conceptual design of such an absorber, capable of operating at 2+ MW primary proton beam power, is described.
 
 
THOCN4 High-Power Options for LANSCE DTL, linac, neutron, klystron 2107
 
  • R.W. Garnett, E.J. Pitcher, D. Rees, L. Rybarcyk, T. Tajima
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work is supported by the U. S. Department of Energy Contract DE-AC52-06NA25396.
The LANSCE linear accelerator at Los Alamos National Laboratory has a long history of successful beam operations at 800 kW. We have recently studied options for restoration of high-power operations including schemes for increasing the performance to multi-MW levels. In this paper we will discuss the results of this study including the present limitations of the existing accelerating structures at LANSCE, and the high-voltage and RF systems that drive them. Several plausible options will be discussed and a preferred option will be presented that will enable the first in a new generation of scientific facilities for the materials community. The emphasis of this new facility is "Matter-Radiation Interactions in Extremes" (MaRIE) which will be used to discover and design the advanced materials needed to meet 21st century national security and energy security challenges.
 
slides icon Slides THOCN4 [2.903 MB]  
 
THOCN7 Isochronous (CW) High Intensity Non-scaling FFAG Proton Drivers focusing, acceleration, cyclotron, simulation 2116
 
  • C. Johnstone
    Fermilab, Batavia, USA
  • M. Berz, K. Makino
    MSU, East Lansing, Michigan, USA
  • S.R. Koscielniak
    TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
  • P. Snopok
    IIT, Chicago, Illinois, USA
 
  Funding: Work supported in part under SBIR grant DE-FG02-08ER85222 and by Fermi Research Alliance, under contract DEAC02-07CH11359, both with the U.S. Dept. of Energy
The drive for higher beam power, duty cycle, and reliable beams at reasonable cost has focused world interest on fixed field accelerators, notably FFAGs. High-intensity GeV proton drivers encounter duty cycle and space-charge limits in the synchrotron and machine size concerns in cyclotrons. A 10-20 MW proton driver is challenging, if even technically feasible, with conventional circular accelerators. Recently, the concept of isochronous orbits has been developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. Isochronous orbits enable the simplicity of fixed RF and, by tailoring the field profile, the FFAG can remain isochronous beyond the energy reach of cyclotrons. With isochronous orbits, the machine proposed here has the high average current advantage and duty cycle of the cyclotron in combination with the strong focusing, smaller losses that are more typical of the synchrotron. With the cyclotron as the current industrial and medical standard, a competing CW FFAG would impact facilities using medical accelerators, proton drivers for neutron production, and accelerator-driven nuclear reactors. This work reports on these new advances.
 
slides icon Slides THOCN7 [2.429 MB]  
 
THP005 High Power Cyclotron Complex for Neutron Production cyclotron, acceleration, electron, extraction 2145
 
  • Yu.G. Alenitsky, A.A. Glazov, G.A. Karamysheva, S.A. Kostromin, E. Samsonov
    JINR, Dubna, Moscow Region, Russia
  • S.N. Dolya, L.M. Onischenko, S.B. Vorozhtsov, N.L. Zaplatin
    JINR/DLNP, Dubna, Moscow region, Russia
 
  Now the cyclotron seems as the most suitable accelerator for production of proton beams with energy up to Ep= 800 MeV and the power Pp=10 MW. There are some offers on creation of such complexes, all of them have common properties. A full cycle of acceleration consists of three stages: high-voltage injection with bunching of continuous beam, then preliminary acceleration in fore sectors cyclotron and acceleration up to the maximal energy 500-800 MeV in the ring cyclotron with six or more sectors. At the first stage of acceleration instead of high-voltage injection one can use the parallel work of two cyclotrons with injection in the subsequent cascade of a beam of the double intensity. In our department of New Accelerators the magnetic and high-frequency systems of a ring cyclotron on the energy 50 - 800 MeV (so-called “supercyclotron”) have been developed. A project of cyclotron injector with energy of protons about 10 MeV has been suggested as injector for Fasotron JINR LNP. It is offered to continue development of the project of cyclotron facility with energy of protons Ер ~ 800 MeV and average current of beam up to 10 mA.  
 
THP027 Status and Development of a Proton FFAG Accelerator at KURRI for ADSR Study injection, linac, ion, ion-source 2172
 
  • Y. Kuriyama, Y. Ishi, J.-B. Lagrange, Y. Mori, R. Nakano, T. Planche, T. Uesugi, E. Yamakawa
    KURRI, Osaka, Japan
  • Y. Niwa, K. Okabe, I. Sakai
    University of Fukui, Faculty of Engineering, Fukui, Japan
 
  In Kyoto University Research Reactor Institute (KURRI), the fixed-field alternating gradient (FFAG) proton accelerator has been constructed to make an experimental study of accelerator driven sub-critical reactor (ADSR) system with spallation neutrons produced by the accelerator. The world first ADSR experiment has been carried out in March of 2009. The proton FFAG accelerator consists of three FFAG rings; injetor (spiral sector FFAG), booster(radial sector FFAG) and main ring(radial sector FFAG), respectively. In March 2010, the experiment conducted with a thorium-loaded accelerator driven system using the proton FFAG accelerator has also been carried out. In order to increase the beam intensity of the proton FFAG accelerator, a new injector with H ions is under construction. In this scheme, H ions accelerated up to the energy of 11 MeV with a linac are injected into the main ring with charge-exchange injection. In this paper, the details of ADSR experiments with the proton FFAG accelerator at KURRI, and also the R&Ds of the accelerator will be presented.  
 
THP029 Temperature and Optimize Design of Beam Window in the Accelerator target, neutron, vacuum, radiation 2175
 
  • J.J. Tian, H. Hao, G. Liu, H.L. Luo, X.Q. Wang, H.L. Wu
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Careful evaluation of the heat-transfer and corresponding problems is important in the beam window in the design and operation of Accelerator Driven sub-critical System (ADS). Using the Monte-Carlo code Fluka, we studied the energy deposition of the beam window in high power proton accelerator. The temperature distribution of the beam window is calculated in presence of the coolant. The process of computation for various materials will be introduced, and an optimized design scheme is given. The results suggest that some measures could be used to reduce the damage to the beam window, such as dividing current into branch currents, expanding the bunch or using beryllium as the material of the beam window, et al.  
 
THP030 GEANT4 Studies of the Thorium Fuel Cycle simulation, neutron, target, scattering 2178
 
  • C. Bungau
    Manchester University, Manchester, United Kingdom
  • R.J. Barlow
    UMAN, Manchester, United Kingdom
  • A. Bungau, R. Cywinski
    University of Huddersfield, Huddersfield, United Kingdom
 
  Thorium “fuel” has been proposed as an alternative to uranium fuel in nuclear reactors. New GEANT4 developments allow the Monte Carlo code to be used for the first time in order to simulate the time evolution of the concentration of isotopes present in the Thorium fuel cycle. A full study is performed in order to optimise the production of Uranium-233 starting with "pure" Thorium fuels, leading to levels of Uranium-233 which ensure the operation of the nuclear reactor in a regime close to criticality.  
 
THP034 Accelerators for Subcritical Molten Salt Reactors neutron, target, linac, SRF 2181
 
  • R.P. Johnson
    Muons, Inc, Batavia, USA
  • C. Bowman
    ADNA, Los Alamos, New Mexico, USA
 
  Funding: Supported in part by Accelerator Technologies Inc.
Accelerator parameters for subcritical reactors that have been considered in recent studies * are based on using solid nuclear fuel much like that used in all operating critical reactors as well as the thorium-burning accelerator-driven energy amplifier ** proposed by Rubbia et al. An attractive alternative reactor design that used molten salts was experimentally studied at ORNL in the 1960s, where a critical molten salt reactor was successfully operated using enriched U235 or U233 tetrafluoride fuels ***. These experiments give confidence that an accelerator-driven subcritical molten salt reactor will work as well or better than conventional reactors, having better efficiency due to their higher operating temperature and having the inherent safety of subcritical operation. Moreover, the requirements to drive a molten salt reactor are considerably relaxed compared to a solid fuel reactor, especially regarding accelerator reliability and spallation neutron targetry, to the point that the required technology exists today.
* http://www.er.doe.gov/hep/files/pdfs/ADSWhitePaperFinal.pdf
** http://wikipedia.org/wiki/Energy_amplifier
*** Paul N. Haubenreich and J. R. Engel, Nuc. Apps & Tech, 8, Feb. 1970
 
 
THP045 Proposed Facility Layout for MaRIE electron, radiation, laser, undulator 2202
 
  • J.A. O'Toole, M.J. Bodelson, J.L. Erickson, R.W. Garnett, M.S. Gulley
    LANL, Los Alamos, New Mexico, USA
 
  The MaRIE (Matter-Radiation Interactions in Extremes) experimental facility will be used to advance materials science by providing the tools scientists need to develop materials that will perform predictably and on demand for currently unattainable lifetimes in extreme environments. The Multi-Probe Diagnostic Hall (MPDH) will create probes of matter using both photon- and proton-based diagnostics. The Fission and Fusion Materials Facility (F3) will provide capabilities for materials irradiation studies, subjecting materials to radiation extremes that are present in fission and fusion environments. The Making, Measuring, and Modeling Materials (M4) Facility will foster discovery by design of next-generation materials that will perform with better durability in extreme environments. MaRIE features a 20-GeV electron linac for an X-ray driver. Five X-ray beams will be delivered to the experimental areas. The facility will also deliver an electron beam to MPDH. The existing LANSCE proton beam will be delivered to MPDH and F3 in addition to the existing LANSCE areas. Multiple high power lasers will deliver beams to MPDH. This paper will provide an overview of the MaRIE facility layout.  
 
THP048 Radiation and Thermal Analysis of Production Solenoid for Mu2e Experimental Setup solenoid, target, neutron, radiation 2208
 
  • V.S. Pronskikh, V. Kashikhin, N.V. Mokhov
    Fermilab, Batavia, USA
 
  The Muon-to-Electron (Mu2e) experiment at Fermilab, will seek the evidence of direct muon to electron conversion that cannot be explained by the Standard Model. An 8 GeV 25 kW proton beam will be directed onto a gold target inside a large-bore superconducting Production Solenoid (PS) with the peak field on the axis of ~5T. The negative muons resulting from the pion decay will be captured in the PS aperture and directed by an S-shaped Transport Solenoid towards the stopping target inside the Detector Solenoid. In order for the superconducting magnets to operate reliably and with a sufficient safety margin, the peak neutron flux entering the coils must be reduced by 3 orders of magnitude that is achieved by means of a sophisticated absorber placed in the magnet aperture. The proposed absorber, consisting of W and Cu parts, is optimized for the performance and cost. Results of MARS15 of energy deposition and radiation analysis are reported. The results of the PS magnet thermal analysis, coordinated with the coil cooling scheme, are reported as well for the selected absorber design.  
 
THP055 Status of the RHIC Head-on Beam-beam Compensation Project electron, solenoid, gun, cathode 2223
 
  • W. Fischer, M. Anerella, E.N. Beebe, D. Bruno, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, A.K. Jain, R.F. Lambiase, C. Liu, Y. Luo, M. Mapes, T.A. Miller, C. Montag, B. Oerter, M. Okamura, A.I. Pikin, D. Raparia, Y. Tan, R. Than, P. Thieberger, J.E. Tuozzolo, W. Zhang
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy.
Two electron lenses are under construction for RHIC to partially compensate the head-on beam-beam effect in order to increase both the peak and average luminosity. The final design of the overall system is reported as well as the status of the component design, acquisition, and manufacturing.
 
 
THP058 The Effects of Betatron Phase Advances on Beam-beam and its Compensation in RHIC lattice, betatron, resonance, dynamic-aperture 2232
 
  • Y. Luo, W. Fischer, X. Gu, S. Tepikian, D. Trbojevic
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
In this article we perform simulation studies to investigate the effects of betatron phase advances between the beam-beam interaction points on half-integer resonance driving terms, second order chromaticity and dynamic aperture in RHIC. The betatron phase advances are adjusted with artificial matrices inserted in the middle of arcs. The lattices for 2011 polarized proton (p-p) run and 2010 RHIC Au-Au runs are used in this study. We also scan the betatron phase advances between IP8 and the electron lens for the proposed Blue ring lattice with head-on beam-beam compensation.
 
 
THP062 Beam Experiments Related to the Head-on Beam-beam Compensation Project at RHIC electron, cathode, injection, lattice 2243
 
  • C. Montag, M. Bai, K.A. Drees, W. Fischer, A. Marusic, G. Wang
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Beam experiments have been performed in RHIC to determine some key parameters of the RHIC electron lenses, and to test the capability of verifying lattice modifications by beam measurements. We report the status and recent results of these experiments.
 
 
THP063 Lattice Design for Head-on Beam-Beam Compensation at RHIC quadrupole, lattice, power-supply, betatron 2246
 
  • C. Montag
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Electron lenses for head-on beam-beam compensation will be installed in IP 10 at RHIC. Compensation of the beam-beam effect experienced at IP 8 requires betatron phase advances of ∆ψ=k·π between the proton-proton interaction point at the IP 8, and the electron lens at IP 10. This paper describes the lattice solutions for both the BLUE and the YELLOW ring to achieve this goal.
 
 
THP067 Ambient Beam Motion and its Excitation by "Ghost Lines" in the Tevatron betatron, quadrupole, emittance, focusing 2255
 
  • V.D. Shiltsev
    Fermilab, Batavia, USA
 
  Transverse betatron motion of the Tevatron proton beam is measured and analyzed. It is shown that the motion is coherent and excited by external sources of unknown origins. Observations of the time-varying "ghost lines" in the betatron spectrum are reported.  
 
THP079 Recent RHIC-motivated Polarized Proton Developments in the Brookhaven AGS resonance, polarization, quadrupole, emittance 2282
 
  • V. Schoefer, L. A. Ahrens, M. Bai, S. Binello, M. Blaskiewicz, K.A. Brown, C.J. Gardner, J.W. Glenn, H. Huang, F. Lin, W.W. MacKay, J. Morris, S. Nemesure, T. Roser, S. Tepikian, N. Tsoupas, K. Yip, A. Zelenski, K. Zeno
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
The RHIC polarized proton physics program requires high luminosity and high polarization which depends directly on the intensity, emittances and polarization delivered to RHIC by the injector chain. In the AGS, two partial snakes create gaps in the realized spin-tune around the integers which allows an accelerating beam with sufficiently small vertical emittance and near-integer vertical tune to avoid the imperfection and vertical intrinsic resonances. The same strategy strengthens the many (82) weak horizontal intrinsic resonances crossed during AGS acceleration. A system speeding up these resonance crossings – the AGS JumpQuad system: 82 tiny (0.04) fast (100usec) betatron tune shifts – has been commissioned and evolved during RHIC Runs 09, 10, and 11. Subtle properties of the AGS geometry and lattice, magnified into relevance by the high vertical tune can result in polarization-damaging emittance growth when combined with the Jump Quad gymnastics. Orbit stability is critical. Some aspects of the JumpQuad system, of this commissioning effort and related developments will be described.
 
 
THP101 The MERLIN Simulation Program: New Features used in Studies of the LHC Collimation System using MERLIN scattering, simulation, collimation, target 2312
 
  • R.J. Barlow, R. Appleby, J. Molson, H.L. Owen, A.M. Toader
    UMAN, Manchester, United Kingdom
 
  We present recent developments in the MERLIN particle tracking simulation code, originally developed at DESY. Their use is illustrated by studies of the LHC collimation system. We make detailed comparisons of our results with those of other codes, and also, where possible, with the data. Different beam optics designs are studied, and the effect of new collimator materials for different upgrade scenarios is predicted.  
 
THP102 Simulation Studies of Accelerating Polarized Light Ions at RHIC and AGS resonance, ion, betatron, acceleration 2315
 
  • M. Bai, E.D. Courant, W. Fischer, F. Méot, T. Roser, A. Zelenski
    BNL, Upton, Long Island, New York, USA
 
  Funding: This work was supported by the Department of Energy of U.S.A
As the worlds’s first high energy polarized proton col- lider, RHIC has made significant progresses in measuring the proton spin structure in the past decade. In order to have better understanding of the contribution of u quark and d quark to the proton spin structure, collisions of high energy polarized neutron beams are required. In this paper, we discuss the perspectives of accelerating polarized light ions, like deuteron, Helium-3 and tritium. We also repre- sent simulation studies of accelerating polarized Helium-3 in RHIC.
Brookhaven National Lab., Upton, NY 11973
 
 
THP110 Front End Energy Deposition and Collimation Studies for IDS-NF shielding, factory, target, beam-losses 2333
 
  • C.T. Rogers
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • D.V. Neuffer
    Fermilab, Batavia, USA
  • P. Snopok
    IIT, Chicago, Illinois, USA
 
  Funding: Work supported by DOE, STFC.
The function of the Neutrino Factory front end is to reduce the energy spread and size of the muon beam to a manageable level that will allow reasonable throughput to subsequent system components. Since the Neutrino Factory is a tertiary machine (protons to pions to muons), there is an issue of large background from the pion-producing target. The implications of energy deposition in the front end lattice for the Neutrino Factory are addressed. Several approaches to mitigating the effect are proposed and discussed, including proton absorbers, chicanes, beam collimation, and shielding.
 
 
FROAN1 The European Spallation Source linac, target, neutron, cryomodule 2549
 
  • S. Peggs, H. Danared, M. Eshraqi, H. Hahn, A. Jansson, M. Lindroos, A. Ponton, K. Rathsman, G. Trahern
    ESS, Lund, Sweden
  • S. Bousson
    IPN, Orsay, France
  • R. Calaga
    BNL, Upton, Long Island, New York, USA
  • G. Devanz, R.D. Duperrier
    CEA/DSM/IRFU, France
  • J. Eguia
    Fundación TEKNIKER, Eibar (Gipuzkoa), Spain
  • S. Gammino
    INFN/LNS, Catania, Italy
  • S.P. Møller
    ISA, Aarhus, Denmark
  • C. Oyon
    SPRI, Bilbao, Spain
  • R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
  • T. Satogata
    JLAB, Newport News, Virginia, USA
 
  The European Spallation Source (ESS) is a 5 MW, 2.5 GeV long pulse proton linac, to be built and commissioned in Lund, Sweden. The Accelerator Design Update (ADU) project phase is under way, to be completed at the end of 2012 by the delivery of a Technical Design Report. Improvements to the 2003 ESS design will be summarised, and the latest design activities will be presented.  
slides icon Slides FROAN1 [1.650 MB]  
 
FROAN3 High-Intensity, High-Brightness Polarized and Unpolarized Beam Production in Charge- Exchange Collisions ion, polarization, brightness, solenoid 2555
 
  • A. Zelenski, G. Atoian, J. Ritter, D. Steski, V. Zubets
    BNL, Upton, Long Island, New York, USA
  • V.I. Davydenko, A.V. Ivanov, V.V. Kolmogorov
    BINP SB RAS, Novosibirsk, Russia
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Basic limitations on the high-intensity H ion beam production were experimentally studied in charge-exchange collisions of the neutral atomic hydrogen beam in the Na- vapor jet ionizer cell. These studies are the part of the polarized source upgrade (to 10 mA peak current and 85% polarization) project for RHIC. In the source the atomic hydrogen beam of a 3-5 keV energy and total (equivalent) current up to 5 A is produced by neutralization of proton beam in pulsed hydrogen gas target. Formation of the proton beam (from the surface of the plasma emitter with a low transverse ion temperature ~0.2 eV) is produced by four-electrode spherical multi-aperture ion-optical system with geometrical focusing. The hydrogen atomic beam intensity up to 1.0 A /cm2 (equivalent) was obtained in the Na-jet ionizer aperture of a 2.0 cm diameter. At the first stage of the experiment H beam with 36 mA current, 5 keV energy and ~1.0 cm-mrad normalized emittance was obtained using the flat grids and magnetic focusing. The experimental results of the high-intensity neutral hydrogen beam generation and studies of the charge-exchange polarization processes of this intense beam will be presented.
 
slides icon Slides FROAN3 [6.093 MB]  
 
FROBN3 Project X - New Multi Megawatt Proton Source at Fermilab linac, injection, cavity, collider 2566
 
  • S. Nagaitsev
    Fermilab, Batavia, USA
 
  Fermilab plans to replace its present injection complex consisting of a pulsed linac and 15 Hz Booster with a new injection complex based on a superconducting CW linac. This new proton source should boost the power of the Main Injector to 2 MW and enable new experiments with a high power proton beam in the range of 1-3 GeV. The speaker will present recent developments from the Fermilab Project X R&D.  
slides icon Slides FROBN3 [2.018 MB]