Keyword: quadrupole
Paper Title Other Keywords Page
TUC1C1 Effect of Three-Dimensional Quadrupole Magnet Model on Beam Dynamics in the FODO Line at the Spallation Neutron Source Beam Test Facility simulation, neutron, permanent-magnet, HOM 65
 
  • T.E. Thompson
    ORNL RAD, Oak Ridge, Tennessee, USA
  • A.V. Aleksandrov, T.V. Gorlov, K.J. Ruisard, A.P. Shishlo
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: Supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics. Authored by UT- Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.
The research program at the Spallation Neutron Source (SNS) Beam Test Facility (BTF) focuses on improving accelerator model accuracy. This study explores the effect of two different models of permanent magnet quadrupoles, which comprise a 9.5-cell FODO line in the BTF. The more realistic model includes all higher-order terms, while the simple, in use model, is a perfect quadrupole. Particular attention is paid to high-amplitude particles to understand how the choice of quadrupole model will affect beam halo distributions. In this paper, we compare particle tracking through a FODO line that contains only linear terms - a perfect quadrupole model - to a full 3D model.
 
slides icon Slides TUC1C1 [1.705 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-TUC1C1  
About • Received ※ 01 October 2023 — Revised ※ 06 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 27 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUA4C1 Recent Progress in Loss Control for the ISIS High-Intensity RCS: Geodetic Modelling, Tune Control, and Optimisation controls, lattice, operation, survey 153
 
  • H. Rafique, E.K. Bansal, H.V. Cavanagh, C.M. Warsop
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
 
  ISIS operates a high intensity 50 Hz rapid cycling synchrotron (RCS), accelerating up to 3 x 1013 protons from 70 to 800 MeV. Protons are delivered to one muon and two neutron targets over two target stations, totalling 0.2 MW of beam power, enabling around 1000 experiments for approximately 3500 users a year. Minimisation of beam loss and optimisation of its control are central to achieving the best facility performance with minimal machine activation. We summarise recent work aimed at improving loss control in the RCS. Using geodetic survey data we aim to develop lattice models with realistic magnet alignment errors in cpymad. Building on recent measurement campaigns a new and improved system of tune control has been developed and verified using enhanced lattice models with cpymad. More rigorous and quantitative measures of beam loss have been implemented in graphical user interfaces (GUIs) using the QT GUI toolkit python interface PyQT5, and streaming data using the messaging protocol MQTT, in order to optimise loss control.  
slides icon Slides TUA4C1 [6.044 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-TUA4C1  
About • Received ※ 28 September 2023 — Revised ※ 13 October 2023 — Accepted ※ 16 October 2023 — Issued ※ 29 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUA4C2 Application of Programmable Trim Quadrupoles in Beam Commissioning of CSNS/RCS neutron, MMI, injection, lattice 158
 
  • Y. Li, C.D. Deng, S.Y. Xu
    DNSC, Dongguan, People’s Republic of China
  • Y.W. An, X. Qi, S. Wang, Y.S. Yuan
    IHEP, Beijing, People’s Republic of China
  • H.Y. Liu
    IHEP CSNS, Guangdong Province, People’s Republic of China
 
  The China Spallation Neutron Source (CSNS) achieved its design power of 100 kW in 2020 and is currently stably operating at 140 kW after a series of measures. In the process of increasing beam power, 16 programmable trim quadrupoles were installed in the Rapid Cycling Synchrotron (RCS) of CSNS to enable rapid variation of tunes, effective adjustment of Twiss parameters, and restoration of lattice superperiodicity through the machine cycle. This paper provides a detailed introduction to the design of the trim quadrupoles and preliminary results of the machine study. The beam experiments show that the trim quadrupoles play a crucial role in increasing beam power after exceeding 100 kW.  
slides icon Slides TUA4C2 [4.136 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-TUA4C2  
About • Received ※ 27 September 2023 — Revised ※ 07 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 22 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEA4I1 Development of Non-Destructive Beam Envelope Measurements Using BPMs for Low Beta Heavy Ion Beams in SRF Cavities simulation, cavity, emittance, heavy-ion 284
 
  • T. Nishi, O. Kamigaito, N. Sakamoto, T. Watanabe, K. Yamada
    RIKEN Nishina Center, Wako, Japan
  • T. Adachi
    RIKEN, Saitama, Japan
 
  Accurate measurement and control of the beam envelope are crucial issues, particularly in high-power accelerator facilities. However, the use of destructive monitors is limited to low-intensity beams. Furthermore, in the case of beam transport between superconducting cavities, these destructive monitors are avoided to prevent the generation of dust particles and outgassing. In the Superconducting RIKEN LINAC, or SRILAC [1], we utilize 8 non-destructive Beam Energy Position Monitors (BEPMs)[2] to measure beam positions and energies. Recently we are developing a method for estimating the beam envelope by combining the quadrupole moments from BEPMs, which consist of four cosine-shape electrodes, with transfer matrix[3]. While this method has been applied to electron and proton beams, it has not been practically demonstrated for heavy ion beams in beta ¿0.1 regions. By combining BEPM simulations, we are making progress toward the reproduction of experimental results, overcoming specific issues associated with low beta. This development will present the possibility of a new method for beam envelope measurement in LEBT and MEBT, especially for hadron beam facilities.
[1] K. Yamada et al., in Proc. SRF2021, paper MOOFAV01(2021).
[2] T. Watanabe et al., in Proc. IBIC2020, paper FRAO04 (2020).
[3] R. H. Miller et al., in Proc. HEAC¿83, pp. 603¿605 (1983).
 
slides icon Slides WEA4I1 [10.867 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-WEA4I1  
About • Received ※ 12 October 2023 — Revised ※ 13 October 2023 — Accepted ※ 18 October 2023 — Issued ※ 01 November 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THA2C3 Periodic Solution for Transport of Intense and Coupled Coasting Beams Through Quadrupole Channels solenoid, coupling, lattice, space-charge 372
 
  • C. Xiao, L. Groening
    GSI, Darmstadt, Germany
 
  Imposing defined spinning to a particle beam increases its stability against perturbations from space charge [Y.-L. Cheon et al., Effects of beam spinning on the fourth-order particle resonance of 3D bunched beams in high intensity linear accelerators, Phys. Rev. Accel. & Beams 25, 064002 (2022)]. In order to fully explore this potential, proper matching of intense coupled beams along regular lattices is mandatory. Herein, a novel procedure assuming matched transport is described and bench-marked through simulations. The concept of matched transport along periodic lattices has been extended from uncoupled beams to those with considerable coupling between the two transverse degrees of freedom. For coupled beams, matching means extension of cell-to-cell periodicity from just transverse envelopes to the coupled beam moments and to quantities being derived from these.  
slides icon Slides THA2C3 [1.649 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-THA2C3  
About • Received ※ 25 September 2023 — Revised ※ 08 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 19 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THAFP07 Preliminary Results on Transverse Phase Space Tomography at KOMAC linac, proton, emittance, diagnostics 415
 
  • S. Lee, J.J. Dang, D.-H. Kim, H.S. Kim, H.-J. Kwon, S.P. Yun
    KOMAC, KAERI, Gyeongju, Republic of Korea
 
  Funding: This work has been supported through KOMAC operation fund of KAERI by Ministry of Science and ICT, the Korean government (KAERI ID no. : 524320-23)
Beam loss is a critical issue to be avoid in high power proton accelerators due to machine protection from radiation. Nonlinear processes add higher order moments and cause halo and tail structures to a beam, resulting in beam losses. Hence it becomes more important to characterize beams for high power accelerators. Conventional beam diagnostic methods can measure only approximate elliptical features of a beam and are not suitable for high power beams. Tomography method reconstructs a multidimensional distribution from its lower-dimensional projections. We used this method to reconstruct the 4D transverse (x, x’, y, y’) phase space distribution of the beam from the accelerator at KOMAC (Korea Multipurpose Accelerator Complex). RFQ BTS (Radio Frequency Quadrupole Beam Test System) was constructed and commissioned in 2022. In the BTS, we performed tomography experiements and obtained preliminary results on 4D transverse phase space beam distribution. We also have applied the tomography measurement techniques to the 100 MeV proton linac. In this paper, we describe the tomography measurement system and present the preliminary results obtained from the BTS and the 100 MeV proton linac.
 
slides icon Slides THAFP07 [2.018 MB]  
poster icon Poster THAFP07 [1.035 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-THAFP07  
About • Received ※ 01 October 2023 — Revised ※ 05 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 13 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THBP10 A Linearized Vlasov Method for the Study of Transverse e-Cloud Instabilities simulation, electron, dipole, betatron 462
 
  • S. Johannesson, M. Seidel
    EPFL, Lausanne, Switzerland
  • G. Iadarola
    CERN, Meyrin, Switzerland
 
  Using a Vlasov approach, electron cloud driven instabilities can be modeled to study beam stability on time scales that conventional Particle In Cell simulation methods cannot access. The Vlasov approach uses a linear description of electron cloud forces that accounts for both the betatron tune modulation along the bunch and the dipolar kicks from the electron cloud. Forces from electron clouds formed in quadrupole magnets as well as dipole magnets have been expressed in this formalism. In addition, the Vlasov approach can take into account the effect of chromaticity. To benchmark the Vlasov approach, it was compared with macroparticle simulations using the same linear description of electron cloud forces. The results showed good agreement between the Vlasov approach and macroparticle simulations for strong electron clouds, with both approaches showing a stabilizing effect from positive chromaticity. This stabilizing effect is consistent with observations from the LHC.  
poster icon Poster THBP10 [4.059 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP10  
About • Received ※ 26 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 14 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THBP30 Linear Modelling and Lattice Correction from Betatron Phase Measurements at the Fermilab Recycler NOvA Ring lattice, betatron, dipole, storage-ring 534
 
  • M. Xiao, R. Ainsworth, K.J. Hazelwood, M.-J. Yang
    Fermilab, Batavia, Illinois, USA
 
  Utilizing the measurement of coherent betatron oscilla-tion phase has emerged as a fast and precise approach for identifying and rectifying errors in achieving a desired lattice in CESR (Cornell Electron Storage Ring), using TAO analysis program and BMAD subroutines. One key advantage of betatron phase measurement over ¿ meas-urement is its sensitivity to phase variations between detectors. This software package has been successfully implemented for the Recycler Ring at Fermilab, with the adaptation of different hardware installations. By em-ploying this technique, a linear model of the bare Recy-cler ring was established, enabling the correction of quadrupole errors.  
poster icon Poster THBP30 [1.476 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP30  
About • Received ※ 19 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 27 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRA1C1 New Techniques Method for Improving the Performance of the ALPI Linac linac, cavity, controls, dipole 638
 
  • L. Bellan, C.O. Carletto, M. Comunian, E. Fagotti, M.G. Giacchini, F. Grespan, M. Montis, Y.K.F. Ong, A. Pisent
    INFN/LNL, Legnaro (PD), Italy
 
  The superconductive quarter wave cavities hadron Linac ALPI is the final acceleration stage at the Legnaro National Laboratories. It can accelerate heavy ions from carbon to uranium up to 10 MeV/u for nuclear and applied physics experiments. It is also planned to use it for re-acceleration of the radioactive ion beams for the SPES (Selective Production of Exotic Species) project. In this article we will present the innovative results obtained with swarm intelligence algorithms, in simulations and measurements. In particular, the increment of the longitudinal acceptance for RIB (Radioactive Ion Beams) acceleration, and beam orbit correction without the beam first order measurements will be discussed.  
slides icon Slides FRA1C1 [1.540 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-FRA1C1  
About • Received ※ 01 October 2023 — Revised ※ 06 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 11 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)