Author: Hirosawa, K.
Paper Title Page
TUA3I2 Measurements of Momentum Halo Due to the Reduced RFQ Voltage During the LIPAc Beam Commissioning 112
 
  • K. Hirosawa, A. De Franco, K. Hasegawa, K. Kondo, S. Kwon, K. Masuda, A. Mizuno, M. Sugimoto
    QST Rokkasho, Aomori, Japan
  • F. Bénédetti
    CEA-DRF-IRFU, France
  • Y. Carin, H. Dzitko, D. Gex, I. Moya, F. Scantamburlo
    F4E, Germany
  • J.C. Morales Vega
    Consorcio IFMIF-DONES España, Granada, Spain
  • I. Podadera
    CIEMAT, Madrid, Spain
 
  The Linear IFMIF Prototype Accelerator, LIPAc, is being commissioned aiming in particular at validating the RFQ up to 5MeV beam acceleration. Eventually, the nominal beam of 5 MeV-125 mA in 1 ms/1 Hz pulsed mode was achieved in 2019. The beam operation has been resumed since July 2023 after long maintenance including recovery from unexpected problems in the RFQ RF system. This new phase aims at the commissioning of the full configuration except SRF linac, which is replaced by a temporary beam transport line. Focusing on the RFQ behavior, it will be interesting to operate it at higher duty especially for longer pulses. Indeed, a beam simulation study suggested that the beam extracted from the RFQ includes considerable momentum halo when the RFQ voltage reduces by a few percent, with a slight decrease of mean energy. It can be a potential source of quench like the mismatched beam in the cryomodule. This could be studied measuring the energy from the Time-of-Flight among multiple BPMs while monitoring beam loss around the dipole, where momentum halo should be lost. During the upcoming commissioning, we propose to study them by scanning the RFQ voltage.  
slides icon Slides TUA3I2 [4.465 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-TUA3I2  
About • Received ※ 29 September 2023 — Revised ※ 06 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 29 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRC1I2 High Beam Current Operation with Beam Diagnostics at LIPAc 649
 
  • S. Kwon, T. Akagi, A. De Franco, K. Hirosawa, K. Kondo, K. Masuda, M. Ohta
    QST Rokkasho, Aomori, Japan
  • F. Bénédetti, Y. Carin, F. Cismondi, D. Gex
    IFMIF/EVEDA, Rokkasho, Japan
  • B. Bolzon, N. Chauvin
    CEA-IRFU, Gif-sur-Yvette, France
  • D. Jimenez-Rey, I. Podadera, A. Rodríguez Páramo, V. Villamayor
    CIEMAT, Madrid, Spain
  • L. Maindive
    UGR, Granada, Spain
  • J. Marroncle
    CEA-DRF-IRFU, France
  • J.C. Morales Vega, I. Podadera
    Consorcio IFMIF-DONES España, Granada, Spain
  • M. Poggi
    INFN/LNL, Legnaro (PD), Italy
 
  The Linear IFMIF Prototype Accelerator (LIPAc) is under commissioning in Rokkasho Fusion Institute in Japan and aims to accelerate 125 mA D⁺ at 9 MeV in CW mode for validating the IFMIF accelerator design. To insure a fine characterization and tuning of the machine many beam diagnostics are installed such as CTs, profile/position/loss/bunch length monitors spanning from Injector to the beam dump (BD). The beam operations in 1.0 ms pulsed D⁺ at 5 MeV was successfully completed with a low power BD (Phase B) in 2019. Despite the challenges posed by the pandemic, the crucial transition to a new linac configuration was also finalized to enable operation in 1.0 ms to CW D⁺ at 5 MeV with the high-power BD (Phase B+). Thanks to the efforts of the entire team, the 1st beam operation of Phase B+ was carried out in 2021. We present the experiences and challenges encountered during the beam operations, particularly the findings from the interceptive devices to measure the beam profile and emittance using tungsten wires rackets, SEMGrid. We also discuss the quick results on other beam diagnostics from the beam operation of Phase B+ toward HDC, which are currently conducting in this Summer.  
slides icon Slides FRC1I2 [9.323 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-HB2023-FRC1I2  
About • Received ※ 02 October 2023 — Revised ※ 06 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 23 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)