Keyword: klystron
Paper Title Other Keywords Page
TUPA64 Analysis of Resonant Converter Topology for High-Voltage Modulators resonance, high-voltage, operation, impedance 486
  • M. Sanchez Barrueta, J.T.M. Lyles, M.D.M. Morris
    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
At the Los Alamos Neutron Science Center (LANSCE), we are considering various topologies to replace obsolete charging supplies and capacitor banks that provide high-voltage direct-current (DC) power to the 44, 805-MHz klystron modulators that drive the LANSCE Coupled Cavity Linac (CCL). Among the possible replacement topologies is the High Voltage Converter Modulator (HVCM), originally designed at LANSCE for use at the Spallation Neutron Source (SNS), to be used as a pulsed high-voltage power supply for klystron-based RF transmitters. The HVCM topology uses high frequency transformers with resonant LC networks for efficient energy conversion and a frequency dependent gain, which permits the use of frequency modulation as a control variable to afford pulse flattening and excellent regulation as demonstrated at SNS. A mathematical analysis is presented that links the converter resonant tank components to the frequency dependent output behavior of the converter modulator.
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA64  
About • Received ※ 03 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 22 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPA75 High Gradient Testing Results of the Benchmark a/λ=0.105 Cavity at CERF-NM cavity, GUI, coupling, MMI 505
  • M.R.A. Zuboraj, D.V. Gorelov, T.W. Hall, M.E. Middendorf, D. Rai, E.I. Simakov, T. Tajima
    LANL, Los Alamos, New Mexico, USA
  Funding: This work was supported by Los Alamos National Laboratory’s Laboratory Directed Research and Development (LDRD) Program.
This presentation will report initial results of high gradient testing of two C-band accelerating cavities fabricated at Los Alamos National Laboratory (LANL). At LANL, we commissioned a C-band Engineering Research Facility of New Mexico (CERF-NM) which has unique capability of conditioning and testing accelerating cavities for operation at surface electric fields at the excess of 300 MV/m, powered by a 50 MW, 5.712 GHz Canon klystron. Recently, we fabricated and tested two benchmark copper cavities at CERF-NM. These cavities establish a benchmark for high gradient performance at C-band and the same geometry will be used to provide direct comparison between high gradient performance of cavities fabricated of different alloys and by different fabrication methods. The cavities consist of three cells with one high gradient central cell and two coupling cells on the sides. The ratio of the radius of the coupling iris to the wavelength is a/λ=0.105. This poster will report high gradient test results such as breakdown rates as function of peak surface electric and magnetic fields and pulse heating.
poster icon Poster TUPA75 [0.890 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA75  
About • Received ※ 05 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 01 October 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, linac, 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)  
WEPA62 Design and Commissioning of the ASU CXLS RF System laser, timing, electron, linac 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)  
WEPA64 Design and Commissioning of the ASU CXLS Machine Protection System controls, GUI, detector, machine-protect 770
  • S.P. Jachim, B.J. Cook, J.R.S. Falconer, A.J. Gardeck, W.S. Graves, M.R. Holl, R.S. Rednour, D.M. Smith, J.V. Vela
    Arizona State University, Tempe, USA
  Funding: This work was supported in part by NSF award #1935994.
To protect against fault conditions in the high-power RF transport and accelerating structures of the Arizona State University (ASU) Compact X-Ray Light Source (CXLS), the Machine Protection System (MPS) extinguishes the 6.5-MW RF energy sources within approximately 50 ns of the fault event. In addition, each fault is localized and reported remotely via USB for operational and maintenance purposes. This paper outlines the requirements, design, and performance of the MPS applied on the CXLS.
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA64  
About • Received ※ 13 July 2022 — Revised ※ 28 July 2022 — Accepted ※ 08 August 2022 — Issue date ※ 12 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, linac, 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)  
THYD3 Update on the Status of C-Band Research and Facilities at LANL cavity, cathode, electron, operation 855
  • E.I. Simakov, A.M. Alexander, D.V. Gorelov, T.W. Hall, M.E. Middendorf, D. Rai, T. Tajima, M.R.A. Zuboraj
    LANL, Los Alamos, New Mexico, USA
  Funding: Los Alamos National Laboratory LDRD Program
We will report on the status of two C-band test facilities at Los Alamos National Laboratory (LANL): C-band Engineering Research Facility in New Mexico (CERF-NM), and Cathodes and Rf Interactions in Extremes (CARIE). Modern applications such as X-ray sources require accelerators with optimized cost of construction and operation, naturally calling for high-gradient acceleration. At LANL we commissioned a high gradient test stand powered by a 50 MW, 5.712 GHz Canon klystron. CERF-NM is the first high gradient C-band test facility in the United States. It was fully commissioned in 2021. In the last year, multiple C-band high gradient cavities and components were tested at CERF-NM. Currently we work to implement several updates to the test stand including the ability to remotedly operate at high gradient for the round-the-clock high gradient conditioning. Adding capability to operate at cryogenic temperatures is considered. The construction of CARIE will begin in October of 2022. CARIE will house a cryo-cooled copper RF photoinjector with a high quantum-efficiency cathode and a high gradient accelerator section.
slides icon Slides THYD3 [3.331 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THYD3  
About • Received ※ 31 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 04 October 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)