Keyword: experiment
Paper Title Other Keywords Page
MOA2IO02 The BNL EBPM Electronics, High Performance for Next Generation Storage Rings ion, storage-ring, feedback, operation 1
 
  • K. Vetter
    ORNL, Oak Ridge, Tennessee, USA
  • W.X. Cheng, J. Mead, B. Podobedov, Y. Tian
    BNL, Upton, Long Island, New York, USA
 
  Funding: DOE contract DE-AC02-98CH10886
A custom state-of-the-art RF BPM (EBPM) has been developed and commissioned at the Brookhaven National Laboratory (BNL) National Synchrotron Light Source II (NSLS-II). A collaboration between Lawrence Berkeley National Laboratory (LBNL) Advanced Light Source (ALS) and BNL has proven to be a key element in the success of the NSLS-II EBPM. High stability coherent signal processing has allowed for demonstrated 200nm RMS spatial resolution and true turn-by-turn position measurement capability. Sub-micron 24 hr. stability has been demonstrated at NSLS-II by use of 0.01C RMS thermal regulation of the electronics racks without the need of active pilot tone correction.
 
slides icon Slides MOA2IO02 [4.334 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOA2IO02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOA2CO03 Measurement of Tune Shift with Amplitude from BPM Data with a Single Kicker Pulse ion, kicker, feedback, lattice 6
 
  • Y. Hidaka, W.X. Cheng, B. Podobedov
    BNL, Upton, Long Island, New York, USA
 
  Funding: The study is supported by U.S. DOE under Contract No. DE-AC02-98CH10886.
Measurements of amplitude-dependent tune shift are critical for understanding of nonlinear single particle dynamics in storage rings. The conventional method involves scanning of the kicker amplitude while having a short bunch train at the top of the kicker pulse. In this paper we present a novel, alternative technique that uses a long continuous bunch train, or a sequence of bunch trains, that are spread along the ring, such that different bunches experience different kick amplitudes with a single shot of a kicker pulse. With these beams, a curve of tune shift with amplitude can be extracted from the recently added new NSLS-II BPM feature called gated turn-by-turn (TbT) BPM data that can resolve bunches within a turn, either alone or together with a bunch-by-bunch BPM data. This technique is immune to pulse-to-pulse jitters and long-term machine drift.
 
slides icon Slides MOA2CO03 [1.961 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOA2CO03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOA4IO02 Recent Progress in High Intensity Operation of the Fermilab Accelerator Complex ion, proton, booster, target 54
 
  • M.E. Convery
    Fermilab, Batavia, Illinois, USA
 
  We report on the status of the Fermilab accelerator complex. Beam delivery to the neutrino experiments surpassed our goals for the past year. The Proton Improvement Plan is well underway with successful 15 Hz beam operation. Beam power of 700 kW to the NOvA experiment was demonstrated and will be routine in the next year. We are also preparing the Muon Campus to commission beam to the g-2 experiment.  
slides icon Slides MOA4IO02 [3.574 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOA4IO02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB05 Tokamak Accelerator ion, plasma, vacuum, ECR 76
 
  • G. Li
    ASIPP, Hefei, People's Republic of China
 
  Tokamak accelerator within plasma is analyzed to be implemented in existing machines for speeding the development of fusion energy with seeding fast particles from high current accelerators - the so-called two-component reactor approach [J. M. Dawson, H. P. Furth, and F. H. Tenney, Phys. Rev. Lett. 26, 1156 (1971)]. All plasma particles are heated at the same time by inductively-coupled power transfer (IPT) within an energy confinement time. This could facilitate the attainment of ignition in tokamak by forming high-gain high-field (HGHF) fusion plasma suggested in [Li. G., Sci. Rep.5, 15790 (2015)]. HGHF mechanism is validated by the flux-conserving process existed in discharges of tokamak plasma at normal operation with long pulses or at compression process within an energy confinement time. Differences between HGHF plasma and former unity-beta plasma are discussed. Tokamak as an accelerator could scale down the design capacity of fusion power plant by simply inserting in-vacuum vertical field coils (IVC) within its vacuum vessel, such as China Fusion Engineering Test Reactor (CFETR).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB05  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB14 Experimental Results of Beryllium Exposed to Intense High Energy Proton Beam Pulses ion, proton, target, radiation 102
 
  • K. Ammigan, B.D. Hartsell, P. Hurh, R.M. Zwaska
    Fermilab, Batavia, Illinois, USA
  • A.R. Atherton
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • M.E.J. Butcher, M. Calviani, M. Guinchard, R. Losito
    CERN, Geneva, Switzerland
  • O. Caretta, T.R. Davenne, C.J. Densham, M.D. Fitton, P. Loveridge, J. O'Dell
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • V.I. Kuksenko, S.G. Roberts
    University of Oxford, Oxford, United Kingdom
  • S.G. Roberts
    CCFE, Abingdon, Oxon, United Kingdom
 
  Funding: Work supported by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Beryllium is extensively used in various accelerator beam lines and target facilities as material for beam windows, and to a lesser extent, as secondary particle production targets. With increasing beam intensities of future accelerator facilities, it is critical to understand the response of beryllium under extreme conditions to reliably operate these components as well as avoid compromising particle production efficiency by limiting beam parameters. As a result, an exploratory experiment at CERN's HiRadMat facility was carried out to take advantage of the test facility's tunable high intensity proton beam to probe and investigate the damage mechanisms of several beryllium grades. The test matrix consisted of multiple arrays of thin discs of varying thicknesses as well as cylinders, each exposed to increasing beam intensities. This paper outlines the experimental measurements, as well as findings from Post-Irradiation-Examination (PIE) work where different imaging techniques were used to analyze and compare surface evolution and microstructural response of the test matrix specimens.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB14  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB23 The Radiation Damage In Accelerator Target Environments (RaDIATE) Collaboration R&D Program - Status and Future Activities ion, radiation, target, proton 117
 
  • P. Hurh
    Fermilab, Batavia, Illinois, USA
 
  Funding: Work supported by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
The RaDIATE collaboration (Radiation Damage In Accelerator Target Environments), founded in 2012, has grown to over 50 participants and 11 institutions globally. The primary objective is to harness existing expertise in nuclear materials and accelerator targets to generate new and useful materials data for application within the accelerator and fission/fusion communities. Current activities include post-irradiation examination of materials taken from existing beamlines (such as the NuMI primary beam window from Fermilab) as well as new irradiations of candidate target materials at low energy and high energy beam facilities. In addition, the program includes thermal shock experiments utilizing high intensity proton beam pulses available at the HiRadMat facility at CERN. Status of current RaDIATE activities as well as future plans will be discussed, including special focus on the upcoming RaDIATE irradiation at the Brookhaven Linac Isotope Producer facility (BLIP) in which multiple materials of interest (e.g. beryllium, graphite, silicon, titanium, iridium) will simultaneously be exposed to 120 - 181 MeV proton beam to relevant radiation damage levels.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB23  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB63 Impact of Cooldown Procedure and Ambient Magnetic Field on the Quality Factor of State-of-the-Art Nb3Sn Single-Cell ILC Cavities ion, cavity, site, factory 215
 
  • D.L. Hall, M. Ge, J.J. Kaufman, M. Liepe, R.D. Porter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: DOE
Single-cell Nb3Sn cavities coated at Cornell University have demonstrated quality factors of 1010 at 16 MV/m and 4.2 K in vertical tests, achieving the performance requirements of contemporary modern accelerator designs. In this paper, we present results demonstrating the impact of the cooldown procedure and ambient magnetic fields on the cavity's ability to achieve these quality factors and accelerating gradients. The impact of the magnetic fields from thermoelectric currents, generated by thermal gradients across the cavity during cooldown, are shown to be equivalent to the impact of magnetic fields trapped from ambient sources. Furthermore, the increase in the residual surface resistance due to trapped magnetic flux, from both ambient sources and thermoelectric currents, is found to be a function of the applied RF magnetic field amplitude. A hypothesis for this observation is given, and conclusions are drawn regarding the demands on the cooldown procedure and ambient magnetic fields necessary to achieve quality factors of 1010 at 4.2 K and 16 MV/m or higher.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB63  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB65 Investigation of the Origin of the Anti-Q-Slope ion, cavity, ECR, SRF 218
 
  • J.T. Maniscalco, M. Ge, D. Gonnella, M. Liepe
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  The surface resistance of a superconductor, a property very relevant to SRF accelerators, has long been known to depend on the strength of the surface magnetic field. A recent discovery showed that, for certain surface treatments, microwave cavities can be shown to have an inverse field dependence, dubbed the ‘‘anti-Q-slope'', in which the surface resistance decreases over an increasing field. Here we present an investigation into what causes the anti-Q-slope in nitrogen-doped niobium cavities, drawing a direct connection between the electron mean free path of the SRF material and the magnitude of the anti-Q-slope. Further, we incorporate residual resistance due to flux trapping to calculate an optimal mean free path for a given trapped flux.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB65  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOB69 Wire Stretching Technique for Measuring RF Crabbing/Deflecting Cavity Electrical Center and a Demonstration Experiment on Its Accuracy ion, cavity, simulation, cryomodule 225
 
  • H. Wang
    JLab, Newport News, Virginia, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The fabrication accuracy of a superconducting RF crab cavity for the Large Hadron Collider High Luminosity Upgrade and the future Electron Ion Collider requires the cavity's electric center line relative to the crabbing plane within sub mm offset and sub degree in rotation. It is very hard for the cavity's niobium sheet formation, high temperature bake and chemistry processes and finally cooling down in cryomodule to satisfy such tight tolerance. A new wire stretching technique combining with the RF measurement in the deflecting modes has been demonstrated on the bench to detect less than 10um resolution on the RF signal when the wire is moving away from the ideal electric center line. The foundation of this technique and its difference from the use in other applications will be reviewed. Based on this principle, the possible implementations for detecting RF leakage to the higher older mode couplers, cavity string alignment and cryomodule assembly will be discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB69  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUA1IO02 Status Report on the SPIRAL2 Facility at GANIL ion, rfq, linac, proton 240
 
  • E. Petit
    GANIL, Caen, France
 
  The GANIL SPIRAL2 project is based on the construction of a superconducting ion CW LINAC with two experimental areas named S3 ('Super Separator Spectrometer') and NFS ('Neutron For Science'). This status will report the construction of the facility and the first beam commissioning results. The perspectives of the SPIRAL2 project, with the future construction of the low energy RIB experimental hall called DESIR and with the construction of a new injector with q/A>1/6 or 1/7, will also be presented.  
slides icon Slides TUA1IO02 [22.004 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUA1IO02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUA2CO04 Vacuum Breakdown at 110 GHz ion, cavity, vacuum, GUI 275
 
  • S.C. Schaub
    MIT, Cambridge, Massachusetts, USA
  • M.A. Shapiro, R.J. Temkin
    MIT/PSFC, Cambridge, Massachusetts, USA
 
  A 1.5 MW, 110 GHz gyrotron is used to produce a linearly polarized quasioptical beam in 3 μs pulses. The beam is concentrated in vacuum to produce strong electric fields on the surfaces of dielectric and metallic samples, which are being tested for breakdown threshold at high fields. Dielectrics are tested in the forms of both windows, with electric fields parallel to the surface, and sub-wavelength dielectric rod waveguides, with electric fields perpendicular to the surface. Currently, visible light emission, absorbed/scattered microwave power, and vacuum pressure diagnostics are used to detect discharges on dielectric surfaces. Future experiments will include dark current diagnostics for direct detection of electrons. Dielectrics to be tested include crystal quartz, fused quartz, sapphire, high resistivity float-zone silicon, and alumina. Metallic accelerator structures will also be tested in collaboration with SLAC. These tests will require shortening of the microwave pulse length to the nanosecond scale.  
slides icon Slides TUA2CO04 [1.826 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUA2CO04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOA04 Study on THz Imaging by Using the Coherent Cherenkov Radiation ion, radiation, electron, detector 296
 
  • M. Nishida, M. Brameld, M. Washio
    Waseda University, Tokyo, Japan
  • R. Kuroda, Y. Taira
    AIST, Tsukuba, Ibaraki, Japan
  • K. Sakaue
    Waseda University, Waseda Institute for Advanced Study, Tokyo, Japan
 
  THz frequency is a special electromagnetic wave which is categorized between a radio wave and a light wave. It can pass through the various materials like a radio wave and can be transported with optical components like a light wave. Thus, it's suitable for imaging application of materials. At Waseda University, it's possible to generate a high-quality electron beam using Cs-Te photocathode RF-Gun and the electron beam is applied to several application researches. As an application of this electron beam, we generate a coherent Cherenkov radiation, and succeed in observing a high power THz light. The successful results of high power THz radiation encourage us to perform the THz imaging with transmission and reflection imaging using some materials, cross-section imaging using a simple material. On studying the THz imaging, it is necessary to clarify the spatial resolution. So, we tried to evaluate the spatial resolution in our device. Furthermore, our target is to get the three-dimensional THz images. We will introduce the CT technique in order to obtain the clear cross-section image. In this conference, we report the recent results of the THz imaging and future prospective.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOA13 First Test Run for High Density Material Imaging Experiment Using Relativistic Electron Beam at the Argonne Wakefield Accelerator ion, electron, target, diagnostics 311
 
  • Y.R. Wang
    AAI/ANL, Argonne, Illinois, USA
  • S. Cao, X.K. Shen, Z.M. Zhang, Q.T. Zhao
    IMP/CAS, Lanzhou, People's Republic of China
  • M.E. Conde, D.S. Doran, W. Gai, W. Liu, J.G. Power, J.Q. Qiu, C. Whiteford, E.E. Wisniewski
    ANL, Argonne, Illinois, USA
 
  A test facility, AWA, has been commissioned and in operation since last year. It can provide beam of several bunches in a train of nano-seconds and 10s of nC with energy up to 70 MeV. In addition, the AWA can accommodate various beamlines for experiments. One of the proposed experiments is to use the AWA beam as a diagnostics for time resolved high density material, typically a target with high Z and time dependent, imaging experiments. When electron beam scatters after passing through the target, and the angular and energy distribution of beam will depend on the density and thickness of the target. A small aperture is used to collimate the scattered electron beam for off axis particles, and the target image will be detected by imaging plate. By measuring the scatted angle and energy at the imaging plate would yield information of the target. In this paper, we report on the AWA electron imaging (EI) system setup, which consist of a target, imaging optics and drift transport. The AWA EI beam line was installed on June, 2016 and the first test run was performed on August, 2016. This work will have implication on the high energy density physics and even future nuclear fusion studies.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA13  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOA42 Multicavity Coherent Pulse Stacking Using Herriott Cells cavity, ion, laser, controls 370
 
  • Y. Yang, J.M. Byrd, L.R. Doolittle, G. Huang, W. Leemans, Q. Qiang, R.B. Wilcox
    LBNL, Berkeley, California, USA
  • J. Dawson
    LLNL, Livermore, California, USA
  • A. Galvanauskas, J.M. Ruppe
    University of Michigan, Ann Arbor, Michigan, USA
  • Y.L. Xu
    TUB, Beijing, People's Republic of China
 
  Coherent Pulse Stacking provides a promising way to generate a single high-intensity laser pulse by stacking a sequence of phase and amplitude modulated laser pulses using multiple optical cavities. Optical misalignment and phase stability are two critical issues that need to be addressed. Herriott cells are implemented for their relaxed alignment tolerance and a phase stabilization method based on cavity output pattern matching has been developed. A single pulse with intensity enhancement factor over 7.4 has been generated by stacking 13 modulated pules through a four-cavity stacking system. This can be a possible path for generating TW KHz laser pulses for a future laser-driven plasma accelerator.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA42  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOA46 Development of a Python-Based Emittance Calculator at Fermilab Science & Technology (FAST) Facility emittance, ion, quadrupole, solenoid 376
 
  • A.T. Green
    Northern Illinois Univerity, DeKalb, Illinois, USA
  • Y.-M. Shin
    Fermilab, Batavia, Illinois, USA
  • Y.-M. Shin
    Northern Illinois University, DeKalb, Illinois, USA
 
  Beam emittance is an important characteristic which helps to describe a charged particle beam. In linear accelerators (linac), it is critical to characterize the beam phase space parameters and, in particular, to precisely measure transverse beam emittance. The quadrupole scan (quad-scan) is a well established technique used to characterize transverse beam parameters in four-dimensional phase space. Quad-scans are very time consuming and off-line analysis is needed to extrapolate the beam phase space parameters. We have developed a computational algorithm with Python scripts to automatically estimate beam parameters, in particular beam emittance, using the quadrupole scan technique in the electron linac of Fermilab Accelerator Science and Technology (FAST) facility. These Python scripts have decreased the time it takes to perform a single quad scan from a few hours to a few minutes. From the experimental data, the emittance calculator quickly delivers various results including: transverse emittance, Courant-Snyder parameters, and Beam Size (squared) vs Quadrupole field strength plots, among others.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA46  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOA49 A General Model of Vacuum Arcs in Linacs ion, plasma, laser, vacuum 387
 
  • J. Norem
    Nano Synergy, Inc., Downers Grove, Illinois, USA
  • Z. Insepov
    Purdue University, West Lafayette, Indiana, USA
 
  We are developing a general model of breakdown and gradient limits that applies to accelerators, along with other high field applications such as power grids and laser ablation. Our recent efforts have considered failure modes of integrated circuits, sheath properties of dense, non-Debye plasmas and applications of capillary wave theory to rf breakdown in linacs. In contrast to much of the rf breakdown effort that considers one physical mechanism or on e experimental geometry, we are finding that there is an enormous volume of relevant material in the literature that helps to constrain our model and suggest experimental tests.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA49  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUB3CO03 Demonstration of fresh slice self seeding in a hard X-ray free electron laser ion, electron, simulation, FEL 450
 
  • C. Emma, C. Pellegrini
    UCLA, Los Angeles, USA
  • M.W. Guetg, A.A. Lutman, A. Marinelli, J. Wu
    SLAC, Menlo Park, California, USA
 
  We discuss the first demonstration of fresh slice self seeding (FSSS) in a hard X-ray Free Electron Laser (XFEL). The FSSS method utilizes a single electron beam to generate a strong seed pulse and amplify it with a small energy spread electron slice. This extends the capability of self seeded XFELs by producing short pulses, not limited by the duration set by the self-seeding monochromator system, with high peak intensity. The scheme relies on using a parallel plate dechirper to impart a spatial chirp on the beam, and appropriate orbit control to lase with different electron beam slices before and after the self-seeding monochromator. The performance of the FSSS method is analyzed with start-to-end simulations for the Linac Coherent Light Source (LCLS). The simulations include the effect of the parallel plate dechirper and propagation of the radiation field through the monochromator. We also present results of the first successful demonstration of FSSS at LCLS. The radiation properties of FSSS X-ray pulses are compared with the Self-Amplified Spontaneous Emission (SASE) mode of FEL operation for the same electron beam parameters.  
slides icon Slides TUB3CO03 [10.423 MB]  
poster icon Poster TUB3CO03 [3.275 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUB3CO03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUB4IO01 Status of the Los Alamos Multi-Probe Facility for Matter-Radiation Interactions in Extremes ion, FEL, electron, linac 464
 
  • J.L. Erickson, R.W. Garnett
    LANL, Los Alamos, New Mexico, USA
 
  The Matter-Radiation Interactions in Extremes (MaRIE) project will provide capability that will address the control of performance and production of materials at the mesoscale. MaRIE will characterize the behavior of interfaces, defects, and microstructure between the spatial scales of atomic structures and those of the engineering continuum where there is a current capability gap. The mission need is well-met with an x-ray source, coherent to optimize disordered imaging capability, brilliant and high-rep-rate to provide time-dependent information, and high enough energy to see into and through the mesoscale of materials of interest. It will be designed for time-dependence from electronic motion (picosecond) through sound waves (nanosecond) through thermal diffusion (millisecond) to manufacturing (seconds and above). The mission need, the requirements, a plausible alternative reference design of a 12-GeV linac-based 42-keV x-ray free-electron laser, and the status of the project will be described.  
slides icon Slides TUB4IO01 [16.013 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUB4IO01  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB06 Accomplishments of the Heavy Electron Particle Accelerator Program ion, collider, factory, proton 489
 
  • D.V. Neuffer, D. Stratakis
    Fermilab, Batavia, Illinois, USA
  • M.A. Cummings
    Muons, Inc, Illinois, USA
  • J.-P. Delahaye
    SLAC, Menlo Park, California, USA
  • M.A. Palmer
    BNL, Upton, Long Island, New York, USA
  • R.D. Ryne
    LBNL, Berkeley, California, USA
  • D.J. Summers
    UMiss, University, Mississippi, USA
 
  Funding: Work supported by Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359
The Muon Accelerator Program has completed a four-year study on the feasibility of muon colliders and on using stored muon beams for neutrinos. That study was broadly successful in its goals, establishing the feasibility of lepton colliders from the 125 GeV Higgs Factory to more than 10 TeV, as well as exploring using μ storage rings for neutrinos. The key components of the muon collider scenarios are a high-intensity proton source, a multi MW target and transport system for π capture, a front end system for bunching, energy compression and initial cooling of μ's, muon cooling systems to obtain intense μ+ and μ- bunches, acceleration up to multiTeV energies, and a collider ring with detectors for high luminosity collisions. For a neutrino factory a similar system could be used but with a racetrack storage ring for ν production and without the cooling needed for high luminosity collisions. Feasible designs and detailed simulations of all of these components have been obtained, including some initial hardware component tests, setting the stage for future implementation where resources are available and clearly associated physics goals become apparent.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB06  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB13 Simulations of Space Charge Neutralization in a Magnetized Electron Cooler ion, electron, simulation, collider 511
 
  • J. Gerity, P.M. McIntyre
    Texas A&M University, College Station, USA
  • D.L. Bruhwiler, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  • V. Moens
    EPFL, Lausanne, Switzerland
  • C.S. Park, G. Stancari
    Fermilab, Batavia, Illinois, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award Number DE-SC0015212.
Magnetized electron cooling at relativistic energies and Ampere scale current is essential to achieve the proposed ion luminosities in a future electron-ion collider (EIC). Neutralization of the space charge in such a cooler can significantly increase the magnetized dynamic friction and, hence, the cooling rate. The Warp framework is being used to simulate magnetized electron beam dynamics during and after the build up of neutralizing ions, via ionization of residual gas in the cooler. The design follows previous experiments at Fermilab as a verification case. We also discuss the relevance to EIC designs.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB13  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB17 Simulations in Support of Wire Beam-Beam Compensation Experiment at the LHC ion, simulation, emittance, optics 525
 
  • A.S. Patapenka
    Northern Illinois University, DeKalb, Illinois, USA
  • R. De Maria, Y. Papaphilippou
    CERN, Geneva, Switzerland
  • A. Valishev
    Fermilab, Batavia, Illinois, USA
 
  The compensation of long-range beam-beam interaction with current wires is considered as a possible technology for the HL-LHC upgrade project. A demonstration experiment is planned in the present LHC machine starting in 2018. This paper summarizes the tracking studies of long range beam-beam effect compensation in the LHC aimed to aid in planning the demonstration experiment. The impact of wire compensators is demonstrated on the tune footprints, dynamic aperture, beam emittance and beam intensity degradation. The simulations are performed with SIXTRACK code. The symplectic transport map for the wire element, its verification and implementation into the code are also discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB17  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB41 Bi-Complex Toolbox Applied to Gyromagnetic Beam Break-Up ion, polarization, dipole, linac 585
 
  • A.V. Smirnov
    RadiaBeam, Santa Monica, California, USA
 
  Transverse instability of a multi-bunch beam in the presence of a longitudinal magnetostatic field and hybrid dipole modes is considered analytically within a single-section model. It incorporates resonant interaction with beam harmonics and eigenmodes, degenerated waves of different polarizations, and the Lorentz RF force contribution. The analysis is performed in a very compact form using a bi-complex i,j-space including four-component collective frequency of the instability. Rotating polarization of the collective field is determined by ImiImj part of the bi-complex collective frequency in agreement with available data. The other three components represent detuning of the collective frequency ReiRej, the left-hand, and right-hand increments ImiRej±ReiImj of the gyro-magnetic BBU effect. The scalar hyper-complex toolbox can be applied to designing of non-ferrite non-reciprocal devices, spin transport, and for characterization of complex transverse dynamics in gyro-devices such as Gyro-TWTs.  
poster icon Poster TUPOB41 [0.526 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB41  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB51 A NUMERICAL STUDY OF THE MICROWAVE INSTABILITY AT APS ion, storage-ring, simulation, vacuum 602
 
  • A. Blednykh, G. Bassi, V.V. Smaluk
    BNL, Upton, Long Island, New York, USA
  • R.R. Lindberg
    ANL, Argonne, Illinois, USA
 
  Funding: This work was supported by Department of Energy contract DE-AC02-98CH10886.
Two particle tracking codes, ELEGANT and SPACE, have been used to simulate the microwave instability in the APS storage ring. The total longitudinal wakepotential for the APS vacuum components, computed by GdfidL, has been used as the input file for the simulations. The numerical results have been compared with bunch length and the energy spread measurements for different single-bunch intensities.
 
poster icon Poster TUPOB51 [1.032 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB51  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB52 Linear Optics Characterization and Correction Method Using Turn-By-Turn BPM Data Based on Resonance Driving Terms with Simultaneous BPM Calibration Capability ion, lattice, coupling, quadrupole 605
 
  • Y. Hidaka, B. Podobedov
    BNL, Upton, Long Island, New York, USA
  • J. Bengtsson
    J B Optima, LLC, Rocky Point, USA
 
  Funding: The study is supported by U.S. DOE under Contract No. DE-AC02-98CH10886.
A fast new linear lattice characterization / correction method based on turn-by-turn (TbT) beam position monitor (BPM) data in storage rings has been recently developed and experimentally demonstrated at NSLS-II. This method performs least-square fitting iteratively on the 4 frequency components extracted from TbT data and dispersion functions. The fitting parameters include the errors for normal/skew quadrupole strength and 4 types of BPM errors (gain, roll, and deformation). The computation of the Jacobian matrix for this system is very fast as it utilizes analytical expressions derived from the resonance driving terms (RDT), from which the method name DTBLOC (Driving-Terms-Based Linear Optics Characterization/Correction) originates. At NSLS-II, a lattice corrected with DTBLOC was estimated to have beta-beating of <1%, dispersion errors of ~1 mm, and emittance coupling ratio on the order of 10-4.
 
poster icon Poster TUPOB52 [2.206 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB52  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOB57 The Role of Adami Information in Beam Cooling ion, kicker, pick-up, beam-cooling 619
 
  • V.H. Ranjbar
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by the US Department of Energy under contract number DE-SC0012704
We re-consider stochastic cooling as type of information engine using the Adami definition of information *. We define information as data which can permit the cooling system to predict the individual trajectories better than purely random prediction and then act on that data to modify the trajectories of an ensemble of particles. In this study we track the flow of this type of information through the closed system and consider the limits based on sampling and correction as well as the role of the underlying model.
* Adami C. 2016 ‘‘What is information?'' Phil. Trans. R. Soc. A 374:20150230.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB57  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEA1CO04 Hollow Electron Beam Collimation for HL-LHC - Effect on the Beam Core ion, simulation, emittance, electron 651
 
  • M. Fitterer, G. Stancari, A. Valishev
    Fermilab, Batavia, Illinois, USA
  • R. Bruce, S. Papadopoulou, G. Papotti, D. Pellegrini, S. Redaelli, D. Valuch, J.F. Wagner
    CERN, Geneva, Switzerland
 
  Funding: Fermilab is operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the US Department of Energy.
Collimation with hollow electron beams or lenses (HEL) is currently one of the most promising concepts for active halo control in HL-LHC. In previous studies it has been shown that the halo can be efficiently removed with a hollow electron lens. Equally important as an efficient removal of the halo, is also to demonstrate that the core stays unperturbed. In this paper, we present a summary of the experiment at the LHC and simulations in view of the effect of the HEL on the beam core in case of a pulsed operation.
 
slides icon Slides WEA1CO04 [1.830 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEA1CO04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEB1CO02 Investigation of Structural Development in the Two-Step Diffusion Coating of Nb3Sn on Niobium ion, niobium, SRF, cavity 659
 
  • U. Pudasaini, M.J. Kelley
    The College of William and Mary, Williamsburg, Virginia, USA
  • G.V. Eremeev, M.J. Kelley, C.E. Reece
    JLab, Newport News, Virginia, USA
  • M.J. Kelley, J. Tuggle
    Virginia Polytechnic Institute and State University, Blacksburg, USA
 
  Funding: Supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-­AC05-­06OR23177 and Office of High Energy Physics under grant SC00144475.
The potential for higher operating temperatures and increased accelerating gradient has attracted SRF researchers to Nb3Sn coatings on niobium for nearly 50 years. The two-step tin vapor diffusion: nucleation followed by deposition appears to be a promising technique to prepare Nb3Sn coatings on interior cavity surface. We have undertaken a fundamental materials study of the nucleation and deposition steps. Nucleation was accomplished within parameter ranges: 300 - 500 °C, 1 - 5 hrs duration, 5 mg - 1 g SnCl2 and 1 g Sn. The resulting deposit consists of (< 10%) coverage of tin particles, as determined by SEM/EDS, while XPS and SAM discovered extra tin film between these particles. Preliminary results by EBSD show no evident effect of substrate crystallography on the crystallography of the final coating. Substantial topography was found to develop during the coating growth.
 
slides icon Slides WEB1CO02 [3.299 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEB1CO02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA02 Progress Toward an Experiment at AWAKE* ion, laser, plasma, diagnostics 687
 
  • P. Muggli
    MPI, Muenchen, Germany
 
  The AWAKE experimental program is scheduled to start at the end of 2016. The aim of the first experiments is to detect and study the self-modulation instability (SMI) of the long proton bunch ~12cm in a plasma with wakefields of period of ~1.2mm. The occurrence of SMI results in the formation of a charge core surrounded by a halo in the time-integrated images of the proton bunch transverse profile. Transverse profiles are obtained from scintillator screens and from optical transition radiation (OTR). The OTR is time resolved using a ps-resolution streak camera to determine the start of the wakefields along the bunch on a slow time scale (~ns), i.e., the location of the seeding of the SMI generated by the ionizing laser pulse. The modulation period is measured using the faster time scale (~ps). Coherent transition radiation (CTR) is analyzed by a heterodyne system to also yield the modulation frequency. Later experiments will sample the wakefields generated by externally injecting low-energy (~15MeV) electrons expected to be accelerated to the GeV energy level over the 10m-long plasma. Progress toward the completion of the experimental set-up will be presented.
*for the AWAKE Collaboration
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA24 Installation and Commissioning of an Ultrafast Electron Diffraction Facility as Part of the ATF-II Upgrade ion, operation, MMI, electron 742
 
  • M.A. Palmer, M. Babzien, M.G. Fedurin, C. Folz, M. Fulkerson, K. Kusche, J.J. Li, R. Malone, T.V. Shaftan, J. Skaritka, L. Snydstrup, C. Swinson, F.J. Willeke
    BNL, Upton, Long Island, New York, USA
 
  Funding: This work was funded by the US Department of Energy under contract DE-SC0012704.
The Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL) is presently carrying out an upgrade, ATF-II, which will provide significantly expanded experimental space and capabilities for its users. One of the new capabilities being integrated into the ATF-II program is an Ultrafast Electron Diffraction (UED) beam line, which was originally deployed in the BNL Source Development Laboratory. Inclusion of the UED in the ATF-II research portfolio will enable ongoing development and extension of the UED capabilities for use in materials research. We discuss the design, installation and commissioning of the UED beam line at ATF-II as well as plans for future upgrades.
 
poster icon Poster WEPOA24 [18.332 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA24  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA26 Fermilab Muon Campus as a Potential Probe to Study Neutrino Physics ion, detector, target, simulation 749
 
  • D. Stratakis, Z. Pavlovic
    Fermilab, Batavia, Illinois, USA
  • J.M. Grange
    ANL, Argonne, Illinois, USA
  • S-C. Kim
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • R. Miceli
    Stony Brook University, Stony Brook, USA
  • J.A. Zennamo
    Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy.
In the next decade the Fermilab Muon Campus will host two world class experiments dedicated to the search for signals of new physics. The Muon g-2 experiment will determine with unprecedented precision the anomalous magnetic moment of the muon. The Mu2e experiment will improve by four orders of magnitude the sensitivity on the search for the as-yet unobserved Charged Lepton Flavor Violation process of a neutrinoless conversion of a muon to an electron. In this paper, we will discuss the possibility for extending the Muon Campus capabilities for neutrino research. With the aid of numerical simulations, we estimate the number of produced neutrinos at various locations along the beamlines as well along the Small Baseline Neutrino Detector which faces one of the straight sections of the delivery ring. Finally, we discuss diagnostics required for realistic implementation of the experiment.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA26  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA29 Recent Experiments at NDCX-II: Irradiation of Materials Using Short, Intense Ion Beams ion, target, plasma, focusing 755
 
  • P.A. Seidl, E. Feinberg, Q. Ji, B.A. Ludewigt, A. Persaud, T. Schenkel, M. Silverman, A.A. Sulyman, W.L. Waldron
    LBNL, Berkeley, California, USA
  • J.J. Barnard, A. Friedman, D.P. Grote
    LLNL, Livermore, California, USA
  • E.P. Gilson, I. Kaganovich, A.D. Stepanov
    PPPL, Princeton, New Jersey, USA
  • F. Treffert, M. Zimmer
    TU Darmstadt, Darmstadt, Germany
 
  Funding: This work was supported by the Office of Science of the US Department of Energy under contracts DE-AC0205CH11231 (LBNL), DE-AC52- 07NA27344 (LLNL) and DE-AC02-09CH11466 (PPPL).
We present an overview of the performance of the Neutralized Drift Compression Experiment-II (NDCX-II) accelerator at Berkeley Lab, and summarize recent studies of material properties created with nanosecond and millimeter-scale ion beam pulses. The scientific topics being explored include the dynamics of ion induced damage in materials, materials synthesis far from equilibrium, warm dense matter and intense beam-plasma physics. We summarize the improved accelerator performance, diagnostics and results of beam-induced irradiation of thin samples of, e.g., tin and silicon. Bunches with over 3x1010 ions, 1-mm radius, and 2-30 ns FWHM duration have been created. To achieve these short pulse durations and mm-scale focal spot radii, the 1.2 MeV He+ ion beam is neutralized in a drift compression section which removes the space charge defocusing effect during final compression and focusing. Quantitative comparison of detailed particle-in-cell simulations with the experiment play an important role in optimizing accelerator performance; these keep pace with the accelerator repetition rate of ~1/minute.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA29  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA35 Wedge Absorbers for Muon Cooling with a Test Beam at MICE ion, emittance, collider, simulation 768
 
  • D.V. Neuffer
    Fermilab, Batavia, Illinois, USA
  • J.G. Acosta, D.J. Summers
    UMiss, University, Mississippi, USA
  • T.A. Mohayai
    IIT, Chicago, Illinois, USA
  • P. Snopok
    Illinois Institute of Technology, Chicago, Illinois, USA
 
  Funding: Work supported by Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359
Emittance exchange mediated by wedge absorbers is required for longitudinal ionization cooling and for final transverse emittance minimization for a muon collider. A wedge absorber within the MICE beam line could serve as a demonstration of the type of emittance exchange needed for 6-D cooling, including the configurations needed for muon colliders. Parameters for this test are explored in simulation and possible experimental configurations with simulated results are presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA35  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA36 Simulated Measurements of Beam Cooling in Muon Ionization Cooling Experiment ion, emittance, solenoid, lattice 771
 
  • T.A. Mohayai
    IIT, Chicago, Illinois, USA
  • D.V. Neuffer, D.V. Neuffer, P. Snopok
    Fermilab, Batavia, Illinois, USA
  • C.T. Rogers
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • P. Snopok
    Illinois Institute of Technology, Chicago, Illinois, USA
 
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Science Graduate Student Research (SCGSR) under contract No. DE-AC05-06OR23100.
Cooled muon beams are essential to enable future Neutrino Factory and Muon Collider facilities. The international Muon Ionization Cooling Experiment (MICE) aims to demonstrate muon beam cooling through ionization energy loss in material. A figure of merit for muon beam cooling in MICE is the transverse root-mean-square (RMS) emittance reduction and to measure this, the individual muon positions and momenta are reconstructed using two scintillating-fiber tracking detectors housed in spectrometer solenoid modules. The reconstructed positions and momenta before and after a low-Z absorbing material are then used for constructing the covariance matrix and measuring normalized transverse RMS emittance of MICE muon beam. However, RMS emittance is sensitive to nonlinear effects in beam optics. In this study, the direct measurement of phase-space density as an alternative approach to measuring the muon beam cooling using the novel Kernel Density Estimation (KDE) method, is described.
 
poster icon Poster WEPOA36 [1.855 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA36  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA37 Hybrid Methods for Simulation of Muon Ionization Cooling Channels ion, simulation, scattering, collider 775
 
  • J.D. Kunz, P. Snopok
    IIT, Chicago, Illinois, USA
  • M. Berz
    MSU, East Lansing, Michigan, USA
  • J.D. Kunz
    Anderson University, Anderson, USA
  • P. Snopok
    Fermilab, Batavia, Illinois, USA
 
  Funding: Work supported by the U.S. Department of Energy
COSY Infinity is an arbitrary-order beam dynamics simulation and analysis code. It uses high-order transfer maps of combinations of particle optical elements of arbitrary field configurations. New features have been developed and implemented in COSY to follow charged particles through matter. To study in detail the properties of muons passing through a material, the transfer map approach alone is not sufficient. The interplay of beam optics and atomic processes must be studied by a hybrid transfer map–Monte Carlo approach in which transfer map methods describe the average behavior of the particles including energy loss, and Monte Carlo methods are used to provide small corrections to the predictions of the transfer map, accounting for the stochastic nature of scattering and straggling of particles. This way the vast majority of the dynamics is represented by fast application of the high-order transfer map of an entire element and accumulated stochastic effects. The gains in speed simplify the optimization of muon cooling channels which are usually very computationally demanding. Progress on the development of the required algorithms is reported.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA37  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA43 Simulations of High Current Magnetic Horn Striplines at Fermilab ion, simulation, site, proton 792
 
  • T. Sipahi, S. Biedron, S.V. Milton
    CSU, Fort Collins, Colorado, USA
  • J. Hylen, R.M. Zwaska
    Fermilab, Batavia, Illinois, USA
 
  Both the NuMI (Neutrinos and the Main Injector) beam line, that has been providing intense neutrino beams for several Fermilab experiments (MINOS, MINERVA, NOVA), and the newly proposed LBNF (Long Baseline Neutrino Facility) beam line, which plans to produce the highest power neutrino beam in the world for DUNE (the Deep Underground Neutrino Experiment), need pulsed magnetic horns to focus the mesons that decay to produce the neutrinos. The high-current horn and stripline design has been evolving as NuMI reconfigures for higher beam power and to meet the needs of the future LBNF program. We evaluated the two existing high-current striplines for NuMI and NOvA at Fermilab by producing Electromagnetic simulations of the magnetic horns and the required high-current striplines. In this paper, we present the comparison of these two designs using the ANSYS Electric and ANSYS Maxwell 3D codes with special attention on the critical stress points. These results are being used to support the development of evolving horn stripline designs to handle increased electrical current and higher beam power for NuMI upgrades and for the LBNF experiment.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA43  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOA51 Update on Photonic Band Gap Accelerating Structure Experiment ion, wakefield, higher-order-mode, photon 807
 
  • J. Upadhyay, E.I. Simakov
    LANL, Los Alamos, New Mexico, USA
 
  Photonic band gap (PBG) structures have great potential in filtering higher order modes (HOMs) without perturbing the fundamental mode and in suppressing the wakefields. An efficient PBG structure would help a lot in terms of beam quality for high beam current future free-electron lasers (FEL). An improved design of X-band normal conducting PBG accelerating structure with elliptical rods will be presented. A comparison of cavity parameters between cylindrical and elliptical shape rod PBG structures will be shown. This new optimized PBG structure would be fabricated and tested at Argonne Wakefield Accelerator (AWA) test facility. The status of the test will be reported.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA51  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEA3CO04 Impedance Characterization and Collective Effects in the MAX IV 3 GeV Ring ion, impedance, synchrotron, feedback 843
 
  • G. Skripka, Å. Andersson, P.F. Tavares
    MAX IV Laboratory, Lund University, Lund, Sweden
  • F.J. Cullinan, R. Nagaoka
    SOLEIL, Gif-sur-Yvette, France
 
  Collective instabilities in the MAX IV 3 GeV storage ring are enhanced by the combination of high beam current, ultralow emittance and small vacuum chamber aperture. To mitigate instabilities by Landau damping and improve lifetime three passive harmonic cavities are installed to introduce synchrotron tune spread and bunch lengthening respectively. We present the results of studies of collective effects driven by the machine impedance. Bunch lengthening and detuning were measured to characterize the effective impedance and estimate the effect of the harmonic cavity potential. Investigations of collective effects as a function of parameters such as beam current and chromaticity are discussed.  
slides icon Slides WEA3CO04 [3.845 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEA3CO04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB20 Multiple Scattering Effects on a Short Pulse Electron Beam Travelling Through Thin Beryllium Foils ion, scattering, vacuum, simulation 937
 
  • E.E. Wisniewski, S.P. Antipov, M.E. Conde, D.S. Doran, W. Gai, Q. Gao, C.-J. Jing, W. Liu, J.G. Power, C. Whiteford
    ANL, Argonne, Illinois, USA
  • S.P. Antipov, C.-J. Jing
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • Q. Gao
    TUB, Beijing, People's Republic of China
  • G. Ha
    POSTECH, Pohang, Kyungbuk, Republic of Korea
 
  Funding: Argonne, a U.S.A. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357.
The Argonne Wakefield Accelerator beamlines have stringent vacuum requirements (100 picotorr) necessitated by the Cesium telluride photoinjector. In direct conflict with this, the structures-based wakefield accelerator research program sometimes includes worthy but complex experimental installations with components or structures unable to meet the vacuum standards. A proposed chamber to sequester such experiments safely behind a thin beryllium (Be) window is described and the results of a study of beam-quality issues due to the multiple scattering of the beam through the window are presented and compared to GEANT4 simulations via G4beamline. Three thicknesses of Be foil were used: 30, 75 and 127 micron, probed by electron beams of three different energies: 25, 45, and 65 MeV. Multiple scattering effects were evaluated by comparing the measured transverse rms beam size for the scattered vs. unscattered beam. The experimental results are presented and compared to simulations. Results are discussed along with the implications and suggestions for the future sequestered vacuum chamber design.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB20  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB26 Observation of Repetition-Rate Dependent Emission From an Un-Gated Thermionic Cathode Rf Gun ion, cathode, gun, electron 956
 
  • J.P. Edelen
    Fermilab, Batavia, Illinois, USA
  • J.R. Harris
    Directed Energy Directorate, Air Force Research Laboratory, Albuquerque, USA
  • J.W. Lewellen
    LANL, Los Alamos, New Mexico, USA
  • Y. Sun
    ANL, Argonne, Illinois, USA
 
  Recent work at Fermilab in collaboration with the Advanced Photon Source and members of other national labs, designed an experiment to study the relationship between the RF repetition rate and the average current per RF pulse. While existing models anticipate a direct relationship between these two parameters we observed an inverse relationship. We believe this is a result of damage to the barium coating on the cathode surface caused by a change in back-bombardment power that is unaccounted for in the existing theories. These observations shed new light on the challenges and fundamental limitations associated with scaling an un-gated thermionic cathode RF gun to high average current.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB26  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB31 Dark Current Study of a Standing Wave Disk-Loaded Waveguide Structure at 17 GHz ion, electron, simulation, multipactoring 971
 
  • H. Xu, M.A. Shapiro, R.J. Temkin
    MIT/PSFC, Cambridge, Massachusetts, USA
 
  Funding: US DoE, Office of High Energy Physics
We present calculations of the dark current in a high gradient accelerator with the intent of understanding its role in breakdown. The initial source of the dark current is the field emission of electrons. For a 17 GHz single-cell standing wave disk-loaded waveguide structure, the 3D particle-in-cell simulation shows that only a small portion of the charge emitted reaches the current monitors at the ends of the structure, while most of the current collides on the structure surfaces, causing secondary electron emission. In the simulation, a two-point multipactor process is observed on the side wall of the cell due to the low electric field on the surface. The multipactor approaches a steady state within nanoseconds when the electric field is suppressed by the electron cloud formed so that the average secondary electron yield is reduced. This multipactor current can cause the ionization of the metal material and surface outgassing, leading to breakdown. We report first results from an experiment designed to extract dark current directly from an accelerator cell from the side through two slits. First results show that the dark current behavior deviates from the field emission theory.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB31  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB41 Quality Factor in High Power Tests of Cryogenic Copper Accelerating Cavities ion, cavity, ECR, GUI 987
 
  • A.D. Cahill, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • V.A. Dolgashev, M.A. Franzi, S.G. Tantawi, S.P. Weathersby
    SLAC, Menlo Park, California, USA
 
  Funding: Research made possible by DOE SCGSR and DOE/SU Contract DE-AC02-76-SF00515
Recent SLAC experiments with cryogenically cooled 11.4 GHz standing wave copper accelerating cavities have shown evidence of 250 MV/m accelerating gradients with low breakdown rates. The gradient depends on the circuit parameters of the accelerating cavity, such as the intrinsic and external quality factors (Q0, QE). In our studies we see evidence that Q0 decreases during rf pulse at 7-70 K. This paper discusses experiments that are directed towards understanding the change of Q0 at high power.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB41  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB42 High Gradient S-Band Cryogenic Accelerating Structure for RF Breakdown Studies ion, cavity, cryogenics, coupling 991
 
  • A.D. Cahill, A. Fukasawa, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • G.B. Bowden, V.A. Dolgashev, S.G. Tantawi
    SLAC, Menlo Park, California, USA
 
  Funding: Work Supported by DOE/SU Contract DE-AC02-76-SF00515 and DOE SCGSR Fellowship
Operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdowns. The limit depends on multiple parameters, including input rf power, rf circuit, cavity shape, cavity temperature, and material. Experimental and theoretical study of the effects of these parameters on the breakdown physics is ongoing at SLAC. As of now, most of the data has been obtained at 11.4 GHz. We are extending this research to S-band. We have designed a single cell accelerating structure, based on the extensively tested X-band cavities. The setup uses matched TM01 mode launcher to feed rf power into the test cavity. Our ongoing study of the physics of rf breakdown in cryogenically X-band accelerating cavities shows improved breakdown performance. Therefore, this S-band experiment is designed to cool the cavity to cryogenic temperatures. We use operating frequencies near 2.856 GHz. We present the rf design and discuss the experimental setup.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB42  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB48 THz and Sub-THz Capabilities of a Table-Top Radiation Source Driven by an RF Thermionic Electron Gun ion, radiation, undulator, electron 998
 
  • A.V. Smirnov, R.B. Agustsson, S. Boucher, T.J. Campese, Y.C. Chen, J.J. Hartzell, B.T. Jacobson, A.Y. Murokh, F.H. O'Shea, E. Spranza
    RadiaBeam, Santa Monica, California, USA
  • W. Berg, M. Borland, J.C. Dooling, L. Erwin, R.R. Lindberg, S.J. Pasky, N. Sereno, Y. Sun, A. Zholents
    ANL, Argonne, Illinois, USA
  • W. Bruns
    WBFB, Berlin, Germany
  • M.J. de Loos, S.B. van der Geer
    Pulsar Physics, Eindhoven, The Netherlands
 
  Funding: This work was supported by the U.S. Department of Energy (award No. DE-SC-FOA-0007702).
Design features and experimental results are presented for a sub-mm wave source [1] based on APS RF thermionic electron gun. The setup includes compact alpha-magnet, quadrupoles, sub-mm-wave radiators, and THz optics. The sub-THz radiator is a planar, oversized structure with gratings. Source upgrade for generation frequencies above 1 THz is discussed. The THz radiator will use a short-period undulator having 1 T field amplitude, ~20 cm length, and integrated with a low-loss oversized waveguide. Both radiators are integrated with a miniature horn antenna and a small ~90°-degree in-vacuum bending magnet. The electron beamline is designed to operate different modes including conversion to a flat beam interacting efficiently with the radiator. The source can be used for cancer diagnostics, surface defectoscopy, and non-destructive testing. Sub-THz experiment demonstrated a good potential of a robust, table-top system for generation of a narrow bandwidth THz radiation. This setup can be considered as a prototype of a compact, laser-free, flexible source capable of generation of long trains of Sub-THz and THz pulses with repetition rates not available with laser-driven sources.
[1] A. V. Smirnov, R. Agustsson, W. J. Berg et al., Phys. Rev. ST Accel. Beams 18, 090703(2015)
 
poster icon Poster WEPOB48 [1.335 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB48  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOB65 Experiments of Lossless Crossing - Resonance With Tune Modulation by Synchrotron Oscillations ion, resonance, lattice, quadrupole 1036
 
  • G.M. Wang, B. Holub, Y. Li, J. Rose, T.V. Shaftan, V.V. Smaluk
    BNL, Upton, Long Island, New York, USA
 
  It had become a standard practice to constrain particle's tune footprint while designing the storage ring lattice so that the tunes fit between harmful resonances that limit ring dynamic aperture (DA). However, in recent ultra-bright light source design, the nonlinearities of storage ring lattices are much enhanced as compared with the 3rd generation light source one. It is becoming more and more difficult to keep the off-momentum tune footprint confined and even more, the solution cannot be found to confine off-energy tune footprint in certain cases. The questions have been asked whether crossing of a resonance stopband from off-momentum particle will necessarily lead to particle loss. In NSLS-II, we modified the lattice working point to mimic machine tune footprint crossing half integer with beam synchrotron oscillation excitation and demonstrated that beam can cross a resonance without loss with control of stopband width and high order chromaticity.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB65  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA08 Transformer Ratio Enhancement Experiment Based on Emittance Exchanger in Argonne Wakefield Accelerator ion, wakefield, GUI, emittance 1115
 
  • Q. Gao, H.B. Chen, J. Shi
    TUB, Beijing, People's Republic of China
  • S.P. Antipov
    Euclid Beamlabs LLC, Bolingbrook, USA
  • M.E. Conde, D.S. Doran, W. Gai, W. Liu, J.G. Power, C. Whiteford, E.E. Wisniewski
    ANL, Argonne, Illinois, USA
  • C.-J. Jing
    Euclid TechLabs, LLC, Solon, Ohio, USA
 
  The transformer ratio is an important figure of merit in collinear wakefield acceleration, it indicates the efficiency of energy transferring from drive bunch to witness bunch. Higher transformer ratio will significantly reduce the length of accelerator thus reducing the cost of accelerator construction. However, for the gaussian bunch, this ratio has its limit of 2. To obtain higher transformer ratio, one possible method is to tailor the beam current profile to specific shapes. One method of beam shaping is based on emittance exchange, which has been demonstrated at the Argonne Wakefield Accelerator. Its principle is to tailor the beam transversely using a mask then exchange the beam's transverse profile and longitudinal profile. In this paper, we describe our efforts to optimize the beamline and mask in order to generate a triangular beam with quadratic head, which has a transformer ratio of 6.4. We also present our design of a dielectric slab based accelerating structure to measure the transformer ratio. Finally, we discuss an experiment for this high transformer ratio at Argonne Wakefield Accelerator Laboratory.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA08  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA22 Linear Lattice and Trajectory Reconstruction and Correction at FAST Linear Accelerator ion, lattice, cavity, solenoid 1149
 
  • A.L. Romanov, D.R. Edstrom
    Fermilab, Batavia, Illinois, USA
  • A. Halavanau
    Northern Illinois University, DeKalb, Illinois, USA
 
  Low energy part of FAST linear accelerator based on 1.3 GHz superconducting RF cavities was successfully commissioned. During commissioning, beam based model dependent methods were used to correct linear lattice and trajectory. Lattice correction algorithm is based on analysis of beam shape from profile monitors and trajectory responses to dipole correctors. Trajectory responses to field gradient variations in quadrupoles and phase variations in superconducting RF cavities were used to correct bunch offsets in quadrupoles and accelerating cavities relative to its magnetic axes. Details of used methods and experimental results are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA22  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA23 Adaptive Matching of the IOTA Ring Linear Optics for Space Charge Compensation ion, lattice, space-charge, insertion 1152
 
  • A.L. Romanov, A. Valishev
    Fermilab, Batavia, Illinois, USA
  • D.L. Bruhwiler, N.M. Cook, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
 
  Many present and future accelerators must operate with high intensity beams when distortions induced by space charge forces are among major limiting factors. Betatron tune depression of above approximately 0.1 per cell leads to significant distortions of linear optics. Many aspects of machine operation depend on proper relations between lattice functions and phase advances, and can be improved with proper treatment of space charge effects. We implement an adaptive algorithm for linear lattice re-matching with full account of space charge in the linear approximation for the case of Fermilab's IOTA ring. The method is based on a search for initial second moments that give closed solution and, at the same time, satisfy predefined set of goals for emittances, beta functions, dispersions and phase advances at and between points of interest. Iterative singular value decomposition based technique is used to search for optimum by varying wide array of model parameters.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA23  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA24 Testing of Advanced Technique for Linear Lattice and Closed Orbit Correction by Modeling Its Application for IOTA Ring at Fermilab ion, lattice, closed-orbit, insertion 1155
 
  • A.L. Romanov
    Fermilab, Batavia, Illinois, USA
 
  Many modern and most future accelerators rely on precise configuration of lattice and trajectory. Integrable Optics Test Accelerator (IOTA) at Fermilab that is coming to final stages of construction will be used to test advanced approaches of control over particles dynamics. Various experiments planned at IOTA require high flexibility of lattice configuration as well as high precision of lattice and closed orbit control. Dense element placement does not allow to have ideal configuration of diagnostics and correctors for all planned experiments. To overcome this limitations advanced method of lattice analysis is proposed that can also be beneficial for other machines. Developed algorithm is based on LOCO approach, extended with various sets of other experimental data, such as dispersion, BPM-to-BPM phase advances, beam shape information from synchrotron light monitors, responses of closed orbit bumps to variations of focusing elements and other. Extensive modeling of corrections for a big number of random seed errors is used to illustrate benefits from developed approach.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA24  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA26 Analysis of the Transport of Muon Polarization for the Fermilab G-2 Muon Experiment ion, proton, polarization, target 1158
 
  • D. Stratakis, K.E. Badgley, M.E. Convery, J.P. Morgan, M.J. Syphers, J.C.T. Thangaraj
    Fermilab, Batavia, Illinois, USA
  • J.D. Crnkovic, W. Morse
    BNL, Upton, Long Island, New York, USA
  • M.J. Syphers
    Northern Illinois University, DeKalb, Illinois, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy.
The Muon g-2 experiment at Fermilab aims to measure the anomalous magnetic moment of the muon to a precision of 140 ppb ─ a fourfold improvement over the 540 ppb precision obtained in BNL experiment E821. Obtaining this precision requires controlling total systematic errors at the 100 ppb level. One form of systematic error on the measurement of the anomalous magnetic moment occurs when the muon beam injected and stored in the ring has a correlation between the muon's spin direction and its momentum. In this paper, we first analyze the creation and transport of muon polarization from the production target to the Muon g-2 storage ring. Then, we detail the spin-momentum and spin-orbit correlations and estimate their impact on the final measurement. Finally, we outline mitigation strategies that could potentially circumvent this problem.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA26  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOA52 A Simulation for Bright THz Light Source from Wiggler Radiation at KEK LUCX ion, wiggler, radiation, simulation 1210
 
  • Y. Sumitomo, S. Araki, A. Aryshev, M.K. Fukuda, M. Shevelev, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • A. Deshpande
    SAMEER, Mumbai, India
  • N. Terunuma
    Sokendai, Ibaraki, Japan
 
  Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
We study a bright THz light source generated by a wiggler radiation at KEK LUCX THz experiment, where an injected four pre-micro-bunched electron beam with few hundreds femto-seconds separation plays a crucial role. The energy of pre-bunched beam reaches few MeV at an S-band 3.6 cell RF Gun, and hence the space-charge effect is not negligible. We simulate the beam optics by ASTRA code, a charged beam optics simulator with space-charge effect, and then the resultant particle distribution is passed to GENESIS, a FEL simulator to deal with the wiggler radiation. We also present an experimental result at KEK LUCX. The major advantage of this system is a compactness of total setup that is expected to generate a MW class peak power THz beam by the coherent radiation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA52  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRA1CO03 An Ultra-High Resolution Pulsed-Wire Magnet Measurement System ion, undulator, radiation, FEL 1268
 
  • A. D'Audney, S. Biedron, S.V. Milton
    CSU, Fort Collins, Colorado, USA
 
  The performance of a Free-Electron Laser (FEL) depends in part on the quality of the magnetic field in the undulator. Imperfections in the magnetic field of an undulator lead to an imperfect electron trajectory, both offset and angle, as well as a relative phase error between the oscillation phase of the electrons and the generated electromagnetic field. The result of such errors is a reduction of laser gain impacting overall FEL performance. A pulsed-wire method can be used to determine the profile of the magnetic field. This is achieved by sending a square-current pulse through a wire placed along the length of the axis that will induce a Lorentz-force interaction with the magnetic field. Measurement of the resulting displacement in the wire over time using a motion detector yields the first or second integrals of the magnetic field and so provides a measure of the local magnetic field strength. Dispersion in the wire can be corrected using algorithms, with a resulting increase in overall accuracy of the measurement. We have designed, constructed and tested a pulsed-wire magnetic measurement system and used this system to characterize the CSU FEL undulator.  
slides icon Slides FRA1CO03 [4.318 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-FRA1CO03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRA1CO05 Progress of Gas-Filled Multi-RF-Cavity Beam Profile Monitor for Intense Neutrino Beams ion, plasma, electron, cavity 1275
 
  • K. Yonehara, M. Backfish, A. Moretti, A.V. Tollestrup, A.C. Watts, R.M. Zwaska
    Fermilab, Batavia, Illinois, USA
  • M.A. Cummings, A. Dudas, R.P. Johnson, G.M. Kazakevich, M.L. Neubauer
    Muons, Inc, Illinois, USA
  • B.T. Freemire
    IIT, Chicago, Illinois, USA
  • Q. Liu
    Case Western Reserve University, Cleveland, USA
 
  Funding: Work supported by Fermilab Research Alliance, LLC under Contract No. DE-AC02-07CH11359 and DOE STTR Grant, No. DE-SC0013795.
A novel pressurized gas-filled multi-RF-cavity beam profile monitor has been studied that is simple and robust in high-radiation environments. Charged particles passing through each RF-cavity in the monitor produce intensity-dependent ionized plasma, which changes the gas permittivity. The sensitivity to beam intensity is adjustable using gas pressure and RF gradient. The performance of the gas-filled beam profile monitor has been numerically simulated to evaluate the sensitivity of permittivity measurements. The result indicates that the RF resonator will be useful to measure the beam profile with a charged beam intensity range from 106 to 1013 protons/bunch. The range covers the expected beam intensities in NuMI and LBNF. The demonstration of the monitor with intense proton beams are taken place at Fermilab to validate the simulation result. The result will be given in this presentation.
 
slides icon Slides FRA1CO05 [3.750 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-FRA1CO05  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)