SRF2017 - List of Keywords (alignment)

Paper	Title	Other Keywords	Page
MOPB096	Estimation of Alignment Error by Measuring Higher-order-mode of Injector Superconducting Cavity at KEK-cERL	cavity, ion, HOM, dipole	286
	Y. Honda, E. Kako, T. Konomi, T. Miyajima, T. Obina, H. Sakai, K. Umemori KEK, Ibaraki, Japan
	Precise alignment of accelerator cavities is important in realizing a low emittance beam. Especially in the cases of superconducting cavities installed in a cryomodule, it is difficult to mechanically measure the position of the cavities. By measuring higher-order-modes (HOM) excited by a beam, the electrical center of the cavities can be estimated. We have developed a HOM measurement system for the injector superconducting accelerator cavities of KEK ERL test accelerator (cERL).Comparing the HOM signals of the three independent cavities in the cryomodule, we estimated the relative positioning errors of the three cavities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB096
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TUPB016	Redesign of CERN's Quadrupole Resonator for Testing of Superconducting Samples	ion, cavity, quadrupole, simulation	420
	V. del Pozo Romano, R. Betemps, F. Gerigk, R. Illan Fiastre, T. Mikkola CERN, Geneva, Switzerland
	The Quadrupole Resonator (QPR) was constructed in 1997 to measure the surface resistance of niobium samples at 400 MHz, the technology and RF frequency chosen for the LHC. It allows measurement of the RF properties of superconducting films deposited on disk-shaped metallic substrates. The samples are used to study different coatings which is much faster than the coating, stripping and re-coating of sample cavities. An electromagnetic and mechanical re-design of the existing QPR has been done with the goal of doubling the magnetic peak fields on the samples. Electromagnetic simulations were carried out on a completely parameterized model, using the actual CERN's QPR as baseline and modifying its dimensions. The aim was to optimize the measurement range and resolution by increasing the ratio between the magnetic peak fields on the sample and in the cavity. Increasing the average magnetic field on the sample leads to a more homogenous field distribution over the sample, which in turn gives a better resolution. Some of the modifications were based on the work already done by Helmholtz-Zentrum-Berlin for their upgraded version of the QPR.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB016
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPB096

Estimation of Alignment Error by Measuring Higher-order-mode of Injector Superconducting Cavity at KEK-cERL

cavity, ion, HOM, dipole

286

Y. Honda, E. Kako, T. Konomi, T. Miyajima, T. Obina, H. Sakai, K. Umemori
KEK, Ibaraki, Japan

Precise alignment of accelerator cavities is important in realizing a low emittance beam. Especially in the cases of superconducting cavities installed in a cryomodule, it is difficult to mechanically measure the position of the cavities. By measuring higher-order-modes (HOM) excited by a beam, the electrical center of the cavities can be estimated. We have developed a HOM measurement system for the injector superconducting accelerator cavities of KEK ERL test accelerator (cERL).Comparing the HOM signals of the three independent cavities in the cryomodule, we estimated the relative positioning errors of the three cavities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB096

Export •

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

TUPB016

Redesign of CERN's Quadrupole Resonator for Testing of Superconducting Samples

ion, cavity, quadrupole, simulation

420

V. del Pozo Romano, R. Betemps, F. Gerigk, R. Illan Fiastre, T. Mikkola
CERN, Geneva, Switzerland

The Quadrupole Resonator (QPR) was constructed in 1997 to measure the surface resistance of niobium samples at 400 MHz, the technology and RF frequency chosen for the LHC. It allows measurement of the RF properties of superconducting films deposited on disk-shaped metallic substrates. The samples are used to study different coatings which is much faster than the coating, stripping and re-coating of sample cavities. An electromagnetic and mechanical re-design of the existing QPR has been done with the goal of doubling the magnetic peak fields on the samples. Electromagnetic simulations were carried out on a completely parameterized model, using the actual CERN's QPR as baseline and modifying its dimensions. The aim was to optimize the measurement range and resolution by increasing the ratio between the magnetic peak fields on the sample and in the cavity. Increasing the average magnetic field on the sample leads to a more homogenous field distribution over the sample, which in turn gives a better resolution. Some of the modifications were based on the work already done by Helmholtz-Zentrum-Berlin for their upgraded version of the QPR.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB016

Export •

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