IPAC2018 - List of Authors (Ao, H.)

Paper	Title	Page
TUPAL022	Low-Reflection RF Window for ACS Cavity in J-PARC Linac	1051
	J. Tamura, Y. Kondo, T. Morishita JAEA/J-PARC, Tokai-mura, Japan H. Ao FRIB, East Lansing, USA F. Naito, M. Otani KEK, Ibaraki, Japan Y. Nemoto Nippon Advanced Technology Co., Ltd., Tokai, Japan
	In the Japan Proton Accelerator Research Complex (J-PARC) linac, the Annular-ring Coupled Structure (ACS) cavities have been stably operating. To maintain this operation availability, we manufactured three backups of the pillbox-type RF windows for the ACS cavities in fiscal year 2015 and 2017. It is desirable to minimize the RF reflection of the RF window to prevent standing waves from exciting between the cavity and the RF window, and not to significantly change the optimized coupling factor between the cavity and the waveguide. To realize the minimization, the relative permittivities of the ceramic disks of the RF windows were evaluated by measuring the resonant frequencies of the pillbox cavity containing the ceramic disk. On the basis of the evaluated relative permittivities, the pillbox-part lengths of the RF windows were determined. The measured Voltage Standing Wave Ratios (VSWRs) of the manufactured RF windows are just about 1.08 and these are applicable for the practical use.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL022
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TUPAL037	Installation Progress on FRIB β=0.041 Cryomodules Toward Beam Commissioning	1087
	H. Ao, B. Bird, N.K. Bultman, F. Casagrande, C. Compton, K.D. Davidson, K. Elliott, V. Ganni, A. Ganshyn, P.E. Gibson, I. Grender, W. Hartung, L. Hodges, K. Holland, A. Hussain, M. Ikegami, S. Jones, P. Knudsen, S.M. Lidia, I.M. Malloch, E.S. Metzgar, S.J. Miller, D.G. Morris, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, M.A. Reaume, T. Russo, K. Saito, M. Shuptar, S. Stanley, S. Stark, D.R. Victory, J. Wei, J.D. Wenstrom, M. Xu, T. Xu, Y. Xu, Y. Yamazaki, Q. Zhao, S. Zhao FRIB, East Lansing, USA A. Facco INFN/LNL, Legnaro (PD), Italy R.E. Laxdal TRIUMF, Vancouver, Canada M. Wiseman JLab, Newport News, Virginia, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 The Facility for Rare Isotope Beams (FRIB) driver linac is to accelerate all the stable ion beams from proton to uranium beyond 200 MeV/u with beam powers up to 400 kW, which will be the first large-scale, CW SRF ion linac. The beam commissioning of the front end (from the ion source to the RFQ) already began and is in progress. The Accelerator Readiness Review (ARR) for beam through the first three β=0.041 cryomodules is scheduled for May 2018. The next step is the beam commissioning through the 12 SRF cavities housed in these 3 cryomodules with 6 superconducting solenoid magnets. The cryomodules and the adjacent warm diagnostics boxes in between have been already installed and aligned in the tunnel. This paper describes the installation progress of the β=0.041 cryomodules and plans for ARR02.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL037
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Low-Reflection RF Window for ACS Cavity in J-PARC Linac

1051

J. Tamura, Y. Kondo, T. Morishita
JAEA/J-PARC, Tokai-mura, Japan
H. Ao
FRIB, East Lansing, USA
F. Naito, M. Otani
KEK, Ibaraki, Japan
Y. Nemoto
Nippon Advanced Technology Co., Ltd., Tokai, Japan

In the Japan Proton Accelerator Research Complex (J-PARC) linac, the Annular-ring Coupled Structure (ACS) cavities have been stably operating. To maintain this operation availability, we manufactured three backups of the pillbox-type RF windows for the ACS cavities in fiscal year 2015 and 2017. It is desirable to minimize the RF reflection of the RF window to prevent standing waves from exciting between the cavity and the RF window, and not to significantly change the optimized coupling factor between the cavity and the waveguide. To realize the minimization, the relative permittivities of the ceramic disks of the RF windows were evaluated by measuring the resonant frequencies of the pillbox cavity containing the ceramic disk. On the basis of the evaluated relative permittivities, the pillbox-part lengths of the RF windows were determined. The measured Voltage Standing Wave Ratios (VSWRs) of the manufactured RF windows are just about 1.08 and these are applicable for the practical use.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL022

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAL037

Installation Progress on FRIB β=0.041 Cryomodules Toward Beam Commissioning

1087

H. Ao, B. Bird, N.K. Bultman, F. Casagrande, C. Compton, K.D. Davidson, K. Elliott, V. Ganni, A. Ganshyn, P.E. Gibson, I. Grender, W. Hartung, L. Hodges, K. Holland, A. Hussain, M. Ikegami, S. Jones, P. Knudsen, S.M. Lidia, I.M. Malloch, E.S. Metzgar, S.J. Miller, D.G. Morris, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, M.A. Reaume, T. Russo, K. Saito, M. Shuptar, S. Stanley, S. Stark, D.R. Victory, J. Wei, J.D. Wenstrom, M. Xu, T. Xu, Y. Xu, Y. Yamazaki, Q. Zhao, S. Zhao
FRIB, East Lansing, USA
A. Facco
INFN/LNL, Legnaro (PD), Italy
R.E. Laxdal
TRIUMF, Vancouver, Canada
M. Wiseman
JLab, Newport News, Virginia, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The Facility for Rare Isotope Beams (FRIB) driver linac is to accelerate all the stable ion beams from proton to uranium beyond 200 MeV/u with beam powers up to 400 kW, which will be the first large-scale, CW SRF ion linac. The beam commissioning of the front end (from the ion source to the RFQ) already began and is in progress. The Accelerator Readiness Review (ARR) for beam through the first three β=0.041 cryomodules is scheduled for May 2018. The next step is the beam commissioning through the 12 SRF cavities housed in these 3 cryomodules with 6 superconducting solenoid magnets. The cryomodules and the adjacent warm diagnostics boxes in between have been already installed and aligned in the tunnel. This paper describes the installation progress of the β=0.041 cryomodules and plans for ARR02.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL037

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)