Keyword: linac
Paper Title Other Keywords Page
MOODE1 Applications of Particle Accelerators electron, site, neutron, target 1
 
  • M. Uesaka
    JAEC, Tokyo, Japan
  
  Applications of particle accelerators amid global policies of carbon neutrality and economic security. are reviewed. Downsizing of high energy large scaled accelerators by advanced technologies enables a variety of medical and industrial uses. One of the highlights is upgrade of sustainable supply chain of medical radioisotopes by the best mix of research reactors and accelerators. 99Mo/99mTc for diagnosis are going to be produced by low enriched U reactor and proton-cyclotron, electron rhodotron and electron linac. Moreover, the theranostics by 177Lu (beta) and 211At/225Ac (alpha) are going to be realized. Proton-cyclotron and electron linac are expected to produce them soon. This new affordable radiation therapy should play an important role in the IAEA project of Rays of Hopes. Next, proof-of-principle trails of on-site bridge inspection of the portable X-band (9.3 GHz) electron linac X-ray/neutron sources are under way. The technical guideline for the practical inspection is to be formed in a couple of years. Ultimate micro-accelerator for microbeam applications is dielectric laser accelerator, such as ACHIP project. Updated projects and results are also introduced.  
slides icon Slides MOODE1 [3.065 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOODE1  
About • Received ※ 02 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 11 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOYE4 Diagnoses and Repair of a Crack in the Drift Tube LINAC Accelerating Structure at LANSCE vacuum, experiment, detector, drift-tube-linac 19
 
  • W.C. Barkley, D.A. Bingham, M.J. Borden, J.A. Burkhart, D.J. Evans, J.T.M. Lyles, J.P. Montross, J.F. O’Hara, B.J. Roller, M. Sanchez Barrueta
    LANL, Los Alamos, New Mexico, USA
  
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
Many were perplexed at the inability of Module 3 at LANSCE to operate at peak power and duty factor while running production beam. During the 2018 production run, the DTL began to intermittently break down, leading to a series of root cause investigations. These analyses included eliminating the usual suspects: vacuum leak, debris in tank, driveline window, power coupler, etc. The throttling back of repetition rate from 120 to 60 Hz allowed continued production with a diminished beam, one that reduced neutron flux to three experimental areas. During the annual shutdown in 2019, a more thorough investigation involving the use of x-ray detection, high-resolution cameras and IR detection through site glass windows was performed. After a tenacious search, a 30 cm long crack was discovered in a weld at one of the ion pump port grates. Inaccessibility for welding from the outside and in a confined space, non-intrusive repairs were tried first but were unsuccessful. Ultimately, an expert welder entered the tank to weld the crack under unfamiliar welding conditions. This paper describes the diagnoses, non-intrusive solutions and ultimate repair of the crack in the accelerating structure. 		 
slides icon Slides MOYE4 [3.232 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOYE4  
About • Received ※ 23 July 2022 — Revised ※ 04 August 2022 — Accepted ※ 05 August 2022 — Issue date ※ 13 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOZD6 Accelerator Physics Lessons from CBETA, the First Multi-Turn SRF ERL electron, SRF, cavity, photon 41
 
  • K.E. Deitrick
    JLab, Newport News, Virginia, USA
  • G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  The Cornell-BNL ERL Test Accelerator (CBETA) has been designed, constructed, and commissioned in a collaboration between Cornell and BNL. It focuses on energy-saving measures in accelerators, including permanent magnets, energy recovery, and superconductors; it has thus been referred to as a green accelerator. CBETA has become the world’s first Energy Recovery Linac (ERL) that accelerates through multiple turns and then recovers the energy in SRF cavities though multiple decelerating turns. The energy is then available to accelerate more beam. It has also become the first accelerator that operates 7 beams in the same large-energy aperture Fixed Field Alternating-gradient (FFA) lattice. The FFA is constructed of permanent combined function magnets and transports energies of 42, 78, 114, and 150 MeV simultaneously. Accelerator physics lessons from the commissioning period will be described and applications of such an accelerator from hadron cooling to EUV lithography and from nuclear physics to a compact Compton source will be discussed.  
slides icon Slides MOZD6 [3.207 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZD6  
About • Received ※ 23 July 2022 — Revised ※ 27 July 2022 — Accepted ※ 03 August 2022 — Issue date ※ 06 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOZE3 Emittance Measurements and Simulations from an X-Band Short-Pulse Ultra-High Gradient Photoinjector emittance, gun, simulation, laser 45
 
  • G. Chen, D.S. Doran, C.-J. Jing, S.Y. Kim, W. Liu, W. Liu, P. Piot, J.G. Power, C. Whiteford, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • C.-J. Jing, E.W. Knight, S.V. Kuzikov
    Euclid TechLabs, Solon, Ohio, USA
  • C.-J. Jing
    Euclid Beamlabs, Bolingbrook, USA
  • X. Lu, P. Piot, W.H. Tan
    Northern Illinois University, DeKalb, Illinois, USA
  
  Funding: This work is supported by the U.S. DOE, under award No. DE-SC0018656 to NIU, DOE SBIR grant No. DE-SC0018709 to Euclid Techlabs LLC, and contract No. DE-AC02-06CH11357 with ANL.
A program is under way at the Argonne Wakefield Accelerator facility, in collaboration with the Euclid Techlabs and Northern Illinois University (NIU), to develop a GeV/m scale photocathode gun, with the ultimate goal of demonstrating a high-brightness photoinjector beamline. The novel X-band photoemission gun (Xgun) is powered by high-power, short RF pulses, 9-ns (FWHM), which, in turn, are generated by the AWA drive beam. In a previous proof-of-principle experiment, an unprecedented 400~MV/m gradient on the photocathode surface* was demonstrated. In the current version of the experiment, we added a linac to the beamline to increase the total energy and gain experience tuning the beamline. In this paper, we report on the very first result of emittance measurement as well as several other beam parameters. This preliminary investigation has identified several factors to be improved on in order to achieve one of the ultimate goals; low emittance.
* W. H. Tan et al., "Demonstration of sub-GV/m Accelerating Field in a Photoemission Electron Gun Powered by Nanosecond X-Band Radiofrequency Pulses", 2022. arXiv:2203.11598v1 		 
slides icon Slides MOZE3 [5.565 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE3  
About • Received ※ 03 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 14 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA09 Design of a 4D Emittance Diagnostic for Low-Energy Ion Beams diagnostics, emittance, quadrupole, simulation 67
 
  • T.R. Curtin, M.S. Curtin
    Ion Linac Systems, Inc., Albuquerque, USA
  
  Characterization of ion beams from an ion injector consisting of an electron-cyclotron-resonance (ECR) source in combination with a low-energy-beam-transport (LEBT) typically exhibits a complex four-dimensional transverse phase-space distribution. The importance of measuring the ion beam correlations following extraction and transport of the low-energy beam is critical to enabling optimization of beam transmission through downstream accelerating structures. A design for a transverse, four-dimensional emittance meter for low-energy protons from the Ion Linac Systems (ILS) ECR-LEBT ion injector is provided.  
poster icon Poster MOPA09 [0.479 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA09  
About • Received ※ 03 August 2022 — Revised ※ 27 September 2022 — Accepted ※ 05 December 2022 — Issue date ※ 05 December 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA27 Validation of the 650 MHz SRF Tuner on the Low and High Beta Cavities for PIP-II at 2 K cavity, SRF, operation, proton 109
 
  • C. Contreras-Martinez, S.K. Chandrasekaran, S. Cheban, G.V. Eremeev, I.V. Gonin, T.N. Khabiboulline, Y.M. Pischalnikov, O.V. Prokofiev, A.I. Sukhanov, J.C. Yun
    Fermilab, Batavia, Illinois, USA
  
  The PIP-II linac will include thirty-six BG=0.61 and twenty-four BG=0.92 650 MHz 5 cell elliptical SRF cavities. Each cavity will be equipped with a tuning system consisting of a double lever slow tuner for coarse frequency tuning and a piezoelectric actuator for fine frequency tuning. The same tuner will be used for both the BG=0.61 and BG=0.92 cavities. Results of testing the cavity-tuner system for the BG=0.61 will be presented for the first time.  
poster icon Poster MOPA27 [0.782 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA27  
About • Received ※ 03 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 04 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA36 Optimization of Superconducting Linac for Proton Improvement Plan-II (PIP-II) emittance, cavity, quadrupole, solenoid 132
 
  • A. Pathak, E. Pozdeyev
    Fermilab, Batavia, Illinois, USA
  
  PIP-II is an essential upgrade of the Fermilab complex that will enable the world’s most intense high-energy beam of neutrinos for the international Deep Underground Neutrino Experiment at LBNF and support a broad physics program at Fermilab. Ultimately, the PIP-II superconducting linac will be capable of accelerating the H− CW beam to 800 MeV with an average power of 1.6 MW. To operate the linac with such high power, beam losses and beam emittance growth must be tightly controlled. In this paper, we present the results of global optimization of the Linac options towards a robust and efficient physics design for the superconducting section of the PIP-II linac. We also investigate the impact of the nonlinear field of the dipole correctors on the beam quality and derive the requirement on the field quality using statistical analysis. Finally, we assess the need to correct the quadrupole focusing produced by Half Wave, and Single Spoke accelerating cavities. We assess the feasibility of controlling the beam coupling in the machine by changing the polarity of the field of Linac focusing solenoids  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA36  
About • Received ※ 02 August 2022 — Revised ※ 04 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 01 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA41 Diagnostics for LINAC Optimization with Machine Learning DTL, network, controls, diagnostics 139
 
  • R.V. Sharankova, M.W. Mwaniki, K. Seiya, M.E. Wesley
    Fermilab, Batavia, Illinois, USA
  
  The Fermilab Linac delivers 400 MeV H− beam to the rest of the accelerator chain. Providing stable intensity, energy, and emittance is key since it directly affects downstream machines. To operate high current beam, accelerators must minimize uncontrolled particle loss; this is generally accomplished by minimizing beam emittance. Ambient temperature and humidity variations are known to affect resonance frequency of the accelerating cavities which induces emittance growth. In addition, the energy and phase space distribution of particles emerging from the ion source are subject to fluctuations. To counter these effects we are working on implementing dynamic longitudinal parameter optimization based on Machine Learning (ML). As an input for the ML model, signals from beam diagnostic have to be well understand and reliable. We have been revisiting diagnostics in the linac. In this presentation we discuss the status of the diagnostics and beam studies as well as the status and plans for ML-based optimization.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA41  
About • Received ※ 05 August 2022 — Accepted ※ 06 August 2022 — Issue date ※ 07 September 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA70 Film Dosimetry Characterization of the Research Linac at the University of Maryland electron, radiation, vacuum, experiment 203
 
  • A.S. Johnson, L.T. Gilde, M.K. Hottinger, T.W. Koeth
    UMD, College Park, Maryland, USA
  
  A heavily modified Varian linac was installed as part of the University of Maryland Radiation Facilities in the early 1980s. The electron linac was initially used for materials testing and pulsed radiolysis. Overtime, diagnostics such as a spectrometer magnet and scintillator screens have been removed, limiting the ability to describe the electron beam. The beamline is currently configured with a thin titanium window to allow the electrons to escape the vacuum region and interact with samples in air. A calibrated film dosimetry system was used to characterize the transverse beam dimensions and uniformity in air. The results of these experimental measurements will be described in this paper.  
poster icon Poster MOPA70 [3.423 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA70  
About • Received ※ 27 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 20 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA83 Automation of Superconducting Cavity and Superconducting Magnet Operation for FRIB cavity, operation, solenoid, cryomodule 239
 
  • W. Chang, Y. Choi, X.-J. Du, W. Hartung, S.H. Kim, T. Konomi, S.R. Kunjir, H. Nguyen, J.T. Popielarski, K. Saito, T. Xu, S. Zhao
    FRIB, East Lansing, Michigan, USA
  
  The superconducting (SC) driver linac for the Facility for Rare Isotope Beams (FRIB) is a heavy-ion accelerator that accelerate ions to 200 MeV per nucleon. The linac has 46 cryomodules that contain 324 SC cavities and 69 SC solenoid packages. For linac operation with high availability and high reliability, automation is essential for such tasks as fast device turn-on/off, fast recovery from trips, and real-time monitoring of operational performance. We have implemented several automation algorithms, including one-button turn-on/off of SC cavities and SC magnets; automated degaussing of SC solenoids; mitigation of field emission-induced multipacting during recovery from cavity trips; and real-time monitoring of the cavity field level calibration. The design, development, and operating experience with automation will be presented.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA83  
About • Received ※ 02 August 2022 — Revised ※ 03 August 2022 — Accepted ※ 06 August 2022 — Issue date ※ 26 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPA84 Superconducting Cavity Commissioning for the FRIB Linac cavity, MMI, cryomodule, controls 242
 
  • W. Chang, W. Hartung, S.H. Kim, T. Konomi, S.R. Kunjir, J.T. Popielarski, K. Saito, T. Xu, S. Zhao
    FRIB, East Lansing, Michigan, USA
  
  The superconducting driver linac for the Facility for Rare Isotope Beams (FRIB) is a heavy ion accelerator that has 46 cryomodules with 324 superconducting (SC) cavities that accelerate ions to 200 MeV per nucleon. Linac commissioning was done in multiple phases, in parallel with technical installation. Ion beam have now been accelerated to the design energy through the full linac; rare isotopes were first produced in December 2021; and the first user experiment was completed in May 2022. All cryomodules were successfully commissioned. Cryomodule commissioning included establishing the desired cavity fields, measuring field emission X-rays, optimizing the tuner control loops, measuring the cavity dynamic heat load, and confirming the low-level RF control (amplitude and phase stability). Results on cryomodule commissioning and cryomodule performance will be presented.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA84  
About • Received ※ 13 July 2022 — Revised ※ 02 August 2022 — Accepted ※ 13 August 2022 — Issue date ※ 05 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUYE4 Machine Learning for Anomaly Detection and Classification in Particle Accelerators network, injection, operation, controls 311
 
  • I. Lobach, M. Borland, K.C. Harkay, N. Kuklev, A. Sannibale, Y. Sun
    ANL, Lemont, Illinois, USA
  
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
We explore the possibility of using a Machine Learning (ML) algorithm to identify the source of occasional poor performance of the Particle Accumulator Ring (PAR) and the Linac-To-PAR (LTP) transport line, which are parts of the injector complex of the Advanced Photon Source (APS) at Argonne National Lab. The cause of reduced injection or extraction efficiencies may be as simple as one parameter being out of range. Still, it may take an expert considerable time to notice it, whereas a well-trained ML model can point at it instantly. In addition, a machine expert might not be immediately available when a problem occurs. Therefore, we began by focusing on such single-parameter anomalies. The training data were generated by creating controlled perturbations of several parameters of PAR and LTP one-by-one, while continuously logging all available process variables. Then, several ML classifiers were trained to recognize certain signatures in the logged data and link them to the sources of poor machine performance. Possible applications of autoencoders and variational autoencoders for unsupervised anomaly detection and for anomaly clustering were considered as well. 		 
slides icon Slides TUYE4 [9.534 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUYE4  
About • Received ※ 03 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 28 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA23 First Beam Results Using the 10-kW Harmonic Rf Solid-State Amplifier for the APS Particle Accumulator Ring injection, booster, photon, rf-amplifier 398
 
  • K.C. Harkay, T.G. Berenc, J.R. Calvey, J.C. Dooling, H. Shang, T.L. Smith, Y. Sun, U. Wienands
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by U. S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source (APS) particle accumulator ring (PAR) was designed to accumulate linac pulses into a single bunch using a fundamental radio frequency (rf) system, and longitudinally compress the beam using a harmonic rf system prior to injection into the booster. The APS Upgrade injectors will need to supply full-current bunch replacement with high single-bunch charge for swap-out injection in the new storage ring. Significant bunch lengthening is observed in the PAR at high charge, which negatively affects beam capture in the booster. Predictions showed that the bunch length could be compressed to better match the booster acceptance using a combination of higher beam energy and higher harmonic gap voltage. A new 10-kW harmonic rf solid-state amplifier (SSA) was installed in 2021 to raise the gap voltage and improve bunch compression. The SSA has been operating reliably. Initial results show that the charge-dependent bunch lengthening in PAR with higher gap voltage agrees qualitatively with predictions. A tool was written to automate bunch length data acquisition. Future plans to increase the beam energy, which makes the SSA more effective, will also be summarized. 		 
poster icon Poster TUPA23 [2.477 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA23  
About • Received ※ 03 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 07 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA36 The Advanced Photon Source Linac Extension Area Beamline electron, gun, photon, lattice 430
 
  • K.P. Wootton, W. Berg, J.M. Byrd, J.C. Dooling, G.I. Fystro, A.H. Lumpkin, Y. Sun, A. Zholents
    ANL, Lemont, Illinois, USA
  • C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  
  Funding: This research used resources of the Advanced Photon Source, operated for the U.S. Department of Energy Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
The Linac Extension Area at the Advanced Photon Source is a flexible beamline area for testing accelerator components and techniques. Driven by the Advanced Photon Source electron linac equipped with a photocathode RF electron gun, the Linac Extension Area houses a 12 m long beamline. The beamline is furnished with YAG screens, BPMs and a magnetic spectrometer to assist with characterization of beam emittance and energy spread. A 1.4 m long insertion in the middle of the beamline is provided for the installation of a device under test. The beamline is expected to be available soon for testing accelerator components and techniques using round and flat electron beams over an energy range 150-450 MeV. In the present work, we describe this beamline and summarise the main beam parameters. 		 
poster icon Poster TUPA36 [0.892 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA36  
About • Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 19 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA38 Sublinear Intensity Response of Cerium-Doped Yttrium Aluminium Garnet Screen with Charge electron, booster, FEL, storage-ring 437
 
  • K.P. Wootton, A.H. Lumpkin
    ANL, Lemont, Illinois, USA
  
  Funding: This research used resources of the Advanced Photon Source, operated for the U.S. Department of Energy Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
Swap-out injection to the Advanced Photon Source Upgrade storage ring necessitates the injection of ~17 nC electron bunches at 6 GeV. To aid with machine tune-up and to measure the beam size, diagnostic imaging screens are envisaged at several locations in the beam transport line from the booster synchrotron to the storage ring. As such, it is important to determine whether the response of these screens to charge is linear. In the present work, we examine the effect of sublinear intensity quenching of a Cerium-doped Yttrium-Aluminium-Garnet scintillator screen. A 1.3 megapixel FLIR BlackFly monochrome digital camera was used to image the beam at the scintillator. At 7 GeV beam energy, over the charge densities investigated (<10 fC um-2), an approximately 10 % reduction of the imaging intensity due to quenching of the scintillator was observed. 		 
poster icon Poster TUPA38 [0.557 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA38  
About • Received ※ 02 August 2022 — Accepted ※ 03 August 2022 — Issue date ※ 09 August 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA44 A Personal History of the Development of the LAMPF/LANSCE Accelerator coupling, operation, DTL, drift-tube-linac 449
 
  • J.M. Potter
    JP Accelerator Works, Los Alamos, New Mexico, USA
  
  The LAMPF/LANSCE accelerator has now been operational for 50 years. I arrived as a LASL employee in Group P11 in April 1964 at the beginning stages of its development. I participated in the development of the resonant coupling principle [1] and went on to develop tuning procedures for the 805-MHz coupled cavity linac (CCL) structures and the post-stabilized drift tube linac (DTL) [2]. The resonant coupling principle is now well established as the basis for rf linear accelerators worldwide. I will discuss the development and building of the accelerator from my viewpoint as a member of a large, dedicated team of physicists, engineers, technicians, and support personnel.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA44  
About • Received ※ 02 August 2022 — Revised ※ 04 August 2022 — Accepted ※ 05 August 2022 — Issue date ※ 05 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA48 Effect of Lattice Misalignments on Beam Dynamics in LANSCE Linear Accelerator alignment, emittance, lattice, simulation 455
 
  • Y.K. Batygin, S.S. Kurennoy
    LANL, Los Alamos, New Mexico, USA
  
  Funding: Work supported by US DOE under contract 89233218CNA000001
Accelerator channel misalignments can significantly affect beam parameters in long linear accelerators. Measurements of misalignments of the LANSCE linac lattice elements was performed by the Mechanical Design Engineering Group of the Los Alamos Accelerator Operations and Technology Division. In order to determine effect of misalignment on beam parameters in LANSCE linac, the start-to-end simulations of LANSCE accelerator were performed using Beampath and CST codes including measured displacements of quadrupoles and accelerating tanks. Simulations were done for both H+ and H− beams with various beam flavors. Effect of misalignments was compared with those due to beam space charge and distortion of RF field along the channel. Paper presents results of simulation and comparison with experimental data of beam emittance growth along the machine. 		 
poster icon Poster TUPA48 [1.547 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA48  
About • Received ※ 23 July 2022 — Revised ※ 28 July 2022 — Accepted ※ 04 August 2022 — Issue date ※ 14 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA56 Beam Coupling Impedances of Asymmetric Components of the Scorpius Induction Linac impedance, resonance, dipole, vacuum 469
 
  • S.S. Kurennoy
    LANL, Los Alamos, New Mexico, USA
  
  The transverse beam coupling impedance of induction linacs must be minimized to avoid beam breakdown instability. The vacuum chamber of the Scorpius linac contains complicated asymmetric elements. We present calculations of the transverse impedance for three asymmetric discontinuities: (1) a pumping section between accelerating cells, which contains vacuum plenum, pumping grid, and bellows; (2) a fast flapper valve; and (3) a debris blocker at the end of the linac. The dipole transverse impedance is calculated with CST Studio using both wakefield solver and eigen solver.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA56  
About • Received ※ 01 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 06 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA57 Electromagnetic and Beam Dynamics Modeling of the LANSCE Coupled-Cavity Linac cavity, simulation, emittance, quadrupole 472
 
  • S.S. Kurennoy, Y.K. Batygin, D.V. Gorelov
    LANL, Los Alamos, New Mexico, USA
  
  The 800-MeV proton linac at LANSCE consists of a drift-tube linac, which brings the beam to 100 MeV, followed by a coupled-cavity linac (CCL) consisting of 44 modules. Each CCL module contains multiple tanks, and it is fed by a single 805-MHz klystron. CCL tanks are multi-cell blocks of identical re-entrant side-coupled cavities, which are followed by drifts with magnetic quadrupole doublets. Bridge couplers - special cavities displaced from the beam axis - electromagnetically couple CCL tanks over such drifts. We have developed 3D CST models of CCL tanks. Their electromagnetic analysis is performed using MicroWave Studio. Beam dynamics is modeled with Particle Studio for bunch trains with realistic beam distributions using the CST calculated RF fields and quadrupole magnetic fields to determine the output beam parameters. Beam dynamics results are crosschecked with other multi-particle codes.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA57  
About • Received ※ 15 July 2022 — Revised ※ 01 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 19 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA77 X-Band Harmonic Longitudinal Phase Space Linearization at the PEGASUS Photoinjector cavity, electron, gun, laser 508
 
  • P.E. Denham, P. Musumeci, A. Ody
    UCLA, Los Angeles, USA
  
  Due to the finite bunch length, photoemitted electron beams sample RF-nonlinearities that lead to energy-time correlations along the bunch temporal profile. This is an important effect for all applications where the projected energy spread is important. In particular, for time-resolved single shot electron microscopy, it is critical to keep the beam energy spread below 1·10-4 to avoid chromatic aberrations in the lenses. Higher harmonic RF cavities can be used to compensate for the RF-induced longitudinal phase space nonlinearities. Start-to-end simulations suggest that this type of compensation can reduce energy spread to the 1·10-5 level. This work is an experimental study of x-band harmonic linearization of a beam longitudinal phase space at the PEGASUS facility, including developing high-resolution spectrometer diagnostics to verify the scheme.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA77  
About • Received ※ 25 July 2022 — Revised ※ 04 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 10 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEXD5 Benchmarking Simulation for AWA Drive Linac and Emittance Exchange Beamline Using OPAL, GPT, and Impact-T simulation, emittance, gun, solenoid 552
 
  • S.Y. Kim, G. Chen, D.S. Doran, G. Ha, W. Liu, J.G. Power, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • E.A. Frame, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  
  At the Argonne Wakefield Accelerator (AWA) facility, particle-tracking simulations have been critical to guiding beam-dynamic experiments, e.g., for various beam manipulations using an available emittance-exchange beamline (EEX). The unique beamline available at AWA provide a test case to perform in-depth comparison between different particle-tracking programs including collective effects such as space-charge force and coherent synchrotron radiation. In this study, using AWA electron injector and emittance exchange beamline, we compare the simulations results obtained by GPT, OPAL, and Impact-T beam-dynamics programs. We will specifically report on convergence test as a function of parameters that controls the underlying algorithms.  
slides icon Slides WEXD5 [1.847 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEXD5  
About • Received ※ 03 August 2022 — Revised ※ 06 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 22 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA23 SRF Cavity Instability Detection with Machine Learning at CEBAF cavity, EPICS, SRF, controls 669
 
  • D.L. Turner, R. Bachimanchi, A. Carpenter, J. Latshaw, C. Tennant, L.S. Vidyaratne
    JLab, Newport News, Virginia, USA
  
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
During the operation of CEBAF, one or more unstable superconducting radio-frequency (SRF) cavities often cause beam loss trips while the unstable cavities themselves do not necessarily trip off. Identifying an unstable cavity out of the hundreds of cavities installed at CEBAF is difficult and time-consuming. The present RF controls for the legacy cavities report at only 1 Hz, which is too slow to detect fast transient instabilities. A fast data acquisition system for the legacy SRF cavities is being developed which samples and reports at 5 kHz to allow for detection of transients. A prototype chassis has been installed and tested in CEBAF. An autoencoder based machine learning model is being developed to identify anomalous SRF cavity behavior. The model is presently being trained on the slow (1 Hz) data that is currently available, and a separate model will be developed and trained using the fast (5 kHz) DAQ data once it becomes available. This paper will discuss the present status of the new fast data acquisition system and results of testing the prototype chassis. This paper will also detail the initial performance metrics of the autoencoder model. 		 
poster icon Poster WEPA23 [1.859 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA23  
About • Received ※ 01 August 2022 — Revised ※ 04 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 24 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA25 Field Emission Mitigation in CEBAF SRF Cavities Using Deep Learning cavity, radiation, detector, neutron 676
 
  • K. Ahammed, J. Li
    ODU, Norfolk, Virginia, USA
  • A. Carpenter, R. Suleiman, C. Tennant, L.S. Vidyaratne
    JLab, Newport News, Virginia, USA
  
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
The Continuous Electron Beam Accelerator Facility (CEBAF) operates hundreds of superconducting radio frequency (SRF) cavities in its two main linear accelerators. Field emission can occur when the cavities are set to high operating RF gradients and is an ongoing operational challenge. This is especially true in newer, higher gradient SRF cavities. Field emission results in damage to accelerator hardware, generates high levels of neutron and gamma radiation, and has deleterious effects on CEBAF operations. So, field emission reduction is imperative for the reliable, high gradient operation of CEBAF that is required by experimenters. Here we explore the use of deep learning architectures via multilayer perceptron to simultaneously model radiation measurements at multiple detectors in response to arbitrary gradient distributions. These models are trained on collected data and could be used to minimize the radiation production through gradient redistribution. This work builds on previous efforts in developing machine learning (ML) models, and is able to produce similar model performance as our previous ML model without requiring knowledge of the field emission onset for each cavity. 		 
poster icon Poster WEPA25 [1.586 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA25  
About • Received ※ 01 August 2022 — Revised ※ 03 August 2022 — Accepted ※ 05 August 2022 — Issue date ※ 20 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA38 Progress on Machine Learning for the SNS High Voltage Converter Modulators network, klystron, electron, simulation 715
 
  • M.I. Radaideh, S.M. Cousineau, D. Lu
    ORNL, Oak Ridge, Tennessee, USA
  • T.J. Britton, K. Rajput, M. Schram, L.S. Vidyaratne
    JLab, Newport News, Virginia, USA
  • G.C. Pappas, J.D. Walden
    ORNL RAD, Oak Ridge, Tennessee, USA
  
  The High-Voltage Converter Modulators (HVCM) used to power the klystrons in the Spallation Neutron Source (SNS) linac were selected as one area to explore machine learning due to reliability issues in the past and the availability of large sets of archived waveforms. Progress in the past two years has resulted in generating a significant amount of simulated and measured data for training neural network models such as recurrent neural networks, convolutional neural networks, and variational autoencoders. Applications in anomaly detection, fault classification, and prognostics of capacitor degradation were pursued in collaboration with the Jefferson Laboratory, and early promising results were achieved. This paper will discuss the progress to date and present results from these efforts.  
poster icon Poster WEPA38 [1.320 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA38  
About • Received ※ 25 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 03 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA40 The L-CAPE Project at FNAL controls, operation, network, alignment 719
 
  • M. Jain, V.C. Amatya, G.U. Panapitiya, J.F. Strube
    PNNL, Richland, Washington, USA
  • B.F. Harrison, K.J. Hazelwood, W. Pellico, B.A. Schupbach, K. Seiya, J.M. St. John
    Fermilab, Batavia, Illinois, USA
  
  The controls system at FNAL records data asynchronously from several thousand Linac devices at their respective cadences, ranging from 15Hz down to once per minute. In case of downtimes, current operations are mostly reactive, investigating the cause of an outage and labeling it after the fact. However, as one of the most upstream systems at the FNAL accelerator complex, the Linac’s foreknowledge of an impending downtime as well as its duration could prompt downstream systems to go into standby, potentially leading to energy savings. The goals of the Linac Condition Anomaly Prediction of Emergence (L-CAPE) project that started in late 2020 are (1) to apply data-analytic methods to improve the information that is available to operators in the control room, and (2) to use machine learning to automate the labeling of outage types as they occur and discover patterns in the data that could lead to the prediction of outages. We present an overview of the challenges in dealing with time-series data from 2000+ devices, our approach to developing an ML-based automated outage labeling system, and the status of augmenting operations by identifying the most likely devices predicting an outage.  
poster icon Poster WEPA40 [1.870 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA40  
About • Received ※ 03 August 2022 — Revised ※ 12 August 2022 — Accepted ※ 17 August 2022 — Issue date ※ 31 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA43 Self-Contained Linac Irradiator for the Sterile Insect Technique (SIT) electron, target, simulation, quadrupole 728
 
  • A. Diego, R.B. Agustsson, R.D. Berry, S. Boucher, O. Chimalpopoca, S.V. Kutsaev, A.Yu. Smirnov, V.S. Yu
    RadiaBeam, Santa Monica, California, USA
  • S.J. Coleman
    RadiaSoft LLC, Boulder, Colorado, USA
  
  Funding: This work was financed by the US department of energy SBIR grant no. DE- SC0020010.
A 3-MeV X-band linac has been developed employing a cost-effective split structure design in order to replace radioactive isotope irradiators currently used for the Sterile Insect Technique (SIT) and other applications. The penetration of a Co-60 irradiator can be matched with Bremsstrahlung produced by a 3-MeV electron beam. The use of electron accelerators eliminates security risks and hazards inherent with radioactive sources. We present the current state of this X-band split structure linac and the rest of the irradiator system. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA43  
About • Received ※ 04 August 2022 — Revised ※ 06 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 16 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA45 Practical Review on Beam Line Commissioning Procedures and Techniques for Scientific and Industrial Electron Accelerators electron, MMI, emittance, operation 735
 
  • M.O. Kravchenko, R.D. Berry, A. Diego, D.I. Gavryushkin, M. Ruelas
    RadiaBeam, Santa Monica, California, USA
  
  Accelerator science has a constant demand requiring improved electron beam quality for both scientific and industrial applications. Examples of parameters on existing systems that affect overall beam quality include: vacuum stability, component level alignment, RF phase matching, electron injection parameters, etc. A proper beam commissioning process allows the characterization of initial parameters that tune system setup appropriately in order to improve net beam quality and becomes a valuable source of data to guide system operation. Here we will discuss methods and possible obstacles during the commissioning process of accelerator systems experienced at RadiaBeam. This includes a description of the diagnostic equipment that may be used to commission a beam line such as: current transformers, faraday cups, profile monitors and pyro detectors. The interpretation of raw data from the diagnostics in terms of usefulness for further adjustments and improvements on the beam line as shown in current work. Simulations and empirical comparisons are also presented as examples for commissioning procedures within the aspect of expectations and actual results.  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA45  
About • Received ※ 30 July 2022 — Revised ※ 04 August 2022 — Accepted ※ 07 August 2022 — Issue date ※ 09 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA48 Electromagnetic Design of a Compact RF Chopper for Heavy-Ion Beam Separation at FRIB cavity, dipole, simulation, MEBT 738
 
  • A.C. Araujo Martinez, R.B. Agustsson, Y.C. Chen, S.V. Kutsaev
    RadiaBeam, Santa Monica, California, USA
  • A.S. Plastun, X. Rao
    FRIB, East Lansing, Michigan, USA
  
  Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics, under SBIR grant DE- SC0020671.
Rare isotope beams are produced at FRIB via fragmentation of a primary heavy ion beam in a thin target. The isotope beam of interest is contaminated with other fragments, which must be filtered out to ensure the delivery of rare isotopes with desired rates and purities. One of the stages of fragment separation uses an RF deflecting cavity to provide time-of-flight separation. However, to avoid neighboring bunches overlapping with each other and with the contaminants, it is necessary to increase the inter-bunch distance by a factor of four, corresponding to a 20.125 MHz rate. To solve this problem, we have developed an RF chopper system for the 500 keV/u primary heavy-ion beams. The system consists of a deflecting quarter wave resonator (QWR) cavity operating at 60.375 MHz, two dipole steering magnets, and a beam dump. In this paper, we present and discuss the optimization of the electromagnetic design of the QWR cavity and magnets, as well as some aspects, related to beam dynamics and conceptual engineering design. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA48  
About • Received ※ 02 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 06 August 2022 — Issue date ※ 08 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA62 Design and Commissioning of the ASU CXLS RF System klystron, laser, timing, electron 764
 
  • B.J. Cook, G.I. Babic, J.R.S. Falconer, W.S. Graves, M.R. Holl, S.P. Jachim, R.E. Larsen
    Arizona State University, Tempe, USA
  
  Funding: This work was supported in part by NSF award #1935994.
The Compact X-ray Light Source (CXLS) uses inverse Compton scattering of a high intensity laser off a bright, relativistic electron beam to produce hard x-rays. The accelerator consists of a photoinjector and three standing-wave linac sections, which are powered by two 6-MW klystrons operating at 9.3 GHz with a repetition rate of 1 kHz. This paper presents the design and commissioning of the CXLS RF systems consisting of both high-power RF structures and low-power diagnostics. The high-power RF system is comprised of two solid state amplifier and klystron modulator sets, various directional couplers, and three phase shifter power dividers. The low-level system consists of a master oscillator and laser phase lock, IQ modulators, IQ demodulators, and downconverters. We present measurements of the low-level and high-power RF phase and amplitude stability showing RMS timing jitter in the tens of femtoseconds and amplitude jitter below 0.1% at high power. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA62  
About • Received ※ 29 July 2022 — Revised ※ 03 August 2022 — Accepted ※ 06 August 2022 — Issue date ※ 19 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA63 Extensions of the Complex (IQ) Baseband RF Cavity Model Including RF Source and Beam Interactions cavity, controls, simulation, beam-loading 767
 
  • S.P. Jachim, B.J. Cook, J.R.S. Falconer
    Arizona State University, Tempe, USA
  
  Funding: This work was supported in part by NSF award #1935994.
This paper extends prior work describing a complex envelope (i.e., baseband) dynamic model of excited accelerator RF cavities, including the effects of frequency detuning, beam loading, reflections, multiple drive ports, and parasitic modes. This model is presented here in closed-form transfer function and state-variable realizations, which may be more appropriate for analytic purposes. Several example simulations illustrate the detailed insight into RF system behavior afforded by this model. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA63  
About • Received ※ 28 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 15 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPA76 Radio Frequency System of the NSLS-II Injector LINAC for Multi-Bunch-Mode Beams controls, klystron, beam-loading, operation 813
 
  • H. Ma, J. Rose, C. Sorrentino
    BNL, Upton, New York, USA
  
  Funding: US DOE, Office of BES
The Multi-Bunch Mode (MBM) beam injection opera-tion of NSLS-II LINAC requires a beam-loading compen-sation for its rf field. That requirement has a significant impact on its radio frequency system (RF), in both the low-level rf control and the high-power klystron transmit-ters. Specifically, for the rf control, it requires the output vector modulation have enough bandwidth to be able to respond the transients by the MBM beam of 40~300 nS long. For the high-power rf transmitters, it requires the klystrons to operate in a near-linear region to be able to respond the linear rf control for the beam-loading compensation, which means a need of ~30% extra rf power overhead, compared to the single-bunch mode operations. The digital signal processing and the network configuration for the rf controllers are also the important areas in the implementation. The original system design was driven by the MBM beam operation requirements, and our system upgrade today continues to be guided by the same principles. 		 
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA76  
About • Received ※ 03 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 24 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THZD1 Instant Phase Setting in a Large Superconducting Linac cavity, SRF, experiment, MMI 885
 
  • A.S. Plastun, P.N. Ostroumov
    FRIB, East Lansing, Michigan, USA
  
  Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement No. DE-SC0000661, the State of Michigan, and Michigan State University.
The instant phase setting reduces the time needed to setup 328 radiofrequency cavities of the Facility for Rare Isotope Beams (FRIB) linac from 20 hours to 10 minutes. This technique uses a 1-D computer model of the linac to predict the cavities’ phases. The model has been accurately calibrated using the data of the 360-degree phase scans - a common procedure for phasing of linear accelerators. The model was validated by comparison with a conventional phase scan results. The predictions applied to the linac are then verified by multiple time-of-flight energy measurements and the response of the beam position/phase monitors (BPMs) to an intentional energy and phase mismatch. The presented approach not just reduces the time and the effort required to tune the FRIB accelerator for new experiments every couple of weeks, but it also provides an easy recovery from cavity failures. It is beneficial for user facilities requiring high beam availability, as well as for radioactive ion beam accelerators, where quick time-of-flight energy measurement via the BPMs is not possible due to the low intensities of these beams. 		 
slides icon Slides THZD1 [2.610 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD1  
About • Received ※ 07 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 21 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THZD3 Design of 3-GeV High-Gradient Booster for Upgraded Proton Radiography at LANSCE booster, proton, focusing, quadrupole 891
 
  • Y.K. Batygin, S.S. Kurennoy
    LANL, Los Alamos, New Mexico, USA
  
  Funding: Work supported by US DOE under contract 89233218CNA000001
Increasing the proton beam energy from the present 800 MeV to 3 GeV will improve the resolution of the Proton Radiography Facility at the Los Alamos Neutron Science Center (LANSCE) by a factor of 10. It will bridge the gap between the existing facilities, which covers large length scales for thick objects, and future high-brightness light sources, which can provide the finest resolution. Proton radiography requires a sequence of short beam pulses (~20 x 80 ns) separated by intervals of variable duration, from about 300 ns to 1 to 2 μs. To achieve the required parameters, the high gradient 3-GeV booster is proposed. The booster consists of 1.4 GHz buncher, two accelerators based on 2.8 GHz and 5.6 GHz high-gradient accelerating structures and 1.4 GHz debuncher. Utilization of buncher-accelerator-debuncher scheme allows us to combine high-gradient acceleration with significant reduction of beam momentum spread. Paper discusses details of linac design and expected beam parameters. 		 
slides icon Slides THZD3 [2.348 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD3  
About • Received ※ 28 July 2022 — Revised ※ 06 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 04 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THZD4 Accelerating Structures for High-Gradient Proton Radiography Booster at LANSCE cavity, booster, proton, distributed 894
 
  • S.S. Kurennoy, Y.K. Batygin, E.R. Olivas
    LANL, Los Alamos, New Mexico, USA
  
  Increasing energy of proton beam at LANSCE from 800 MeV to 3 GeV improves radiography resolution ~10 times. We proposed accomplishing such an energy boost with a compact cost-effective linac based on normal conducting high-gradient (HG) RF accelerating structures. Such an unusual proton linac is feasible for proton radiography (pRad), which operates with short RF pulses. For a compact pRad booster at LANSCE, we have developed a multi-stage design: a short L-band section to capture and compress the 800-MeV proton beam followed by the main HG linac based on S- and C-band cavities, and finally, by an L-band de-buncher [1]. Here we present details of development, including EM and thermal-stress analysis, of proton HG structures with distributed RF coupling for the pRad booster. A simple two-cell structure with distributed coupling is being fabricated and will be tested at the LANL C-band RF Test Stand.
[1] S.S. Kurennoy, Y.K. Batygin. IPAC21, MOPAB210. 		 
slides icon Slides THZD4 [1.591 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD4  
About • Received ※ 01 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 26 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THZD6 An 8 GeV Linac as the Booster Replacement in the Fermilab Power Upgrade injection, cryomodule, cavity, SRF 897
 
  • D.V. Neuffer, S.A. Belomestnykh, M. Checchin, D.E. Johnson, S. Posen, E. Pozdeyev, V.S. Pronskikh, A. Saini, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, Illinois, USA
  
  Funding: Work supported by the Fermi National Accelerator Laboratory, managed and operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Increasing the Main Injector (MI) beam power above ~1.2 MW requires replacement of the 8-GeV Booster by a higher intensity alternative. In the Project X era, rapid-cycling synchrotron (RCS) and linac solutions were considered for this purpose. In this paper, we consider the linac version that produces 8 GeV H− beam for injection into the Recycler Ring (RR) or Main Injector (MI). The linac takes ~1-GeV beam from the PIP-II Linac and accelerates it to ~2 GeV in a 650-MHz SRF linac, followed by a 8-GeV pulsed linac using 1300 MHz cryomodules. The linac components incorporate recent improvements in SRF technology. Research needed to implement the high power SRF Linac is described. 		 
slides icon Slides THZD6 [4.078 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD6  
About • Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 04 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)