LINAC2016 - List of Authors (Kononenko, O.)

Paper	Title	Page
MOP106006	Electro-Mechanical Modeling of the LCLS-II Superconducting Cavities	310
	O. Kononenko, C. Adolphsen, Z. Li, T.O. Raubenheimer, C.H. Rivetta SLAC, Menlo Park, California, USA
	Funding: Work supported by the Department of Energy, Office of Science, Office of Basic Energy Science, under Contract No. DEAC0276SF00515 The 4 GeV LCLS-II superconducting linac will contain 280, 1.3 GHz TESLA-style cavities operated CW at 16 MV/m. Because of the low beam current, the cavity bandwidth will be fairly small, about 32 Hz, which makes the field stability sensitive to detuning from external vibrations and He pressure fluctuations. Piezo-electric actuators will be used to compensate for the detuning, which historically has been difficult at frequencies above a few Hz due to excitation of cavity mechanical resonances. To understand this interaction better, we have been doing extensive modeling of the cavities including mapping out the mechanical modes and computing their coupling to pressure changes, Lorentz forces and piezo actuator motion. One goal is to reproduce the measured detuning response of the piezo actuators up to 1 kHz, which is sensitive to how the cavities are constrained within a cryomodule. In this paper, we summarize these results and their implications for suppressing higher frequency detuning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOP106006
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THPLR028	Simulation of Mechanical Oscillations in PIP-II Cryomodule Using ACE3P	910
	L. Xiao, O. Kononenko, C.-K. Ng SLAC, Menlo Park, California, USA
	Funding: Work supported by the US DOE under contract DE-AC02-76SF00515. The linac in the PIP-II project at Fermilab consists of different sections of superconducting rf (SRF) cavities that can accelerate the proton beams to 800 MeV. At the end of the linac is a section containing a number of HB (β = 0.92) cryomodules operating at 650 MHz, with each cryomodule consisting of six SRF cavities. Previous calculations have been carried out to determine the mechanical modes of a single cavity in the 650 MHz cryomodule. In this paper, the parallel code suite ACE3P is used to evaluate the mechanical modes for a string of SRF cavities in the 650 MHz cryomodule. The effects of multi cavities on the mechanical mode frequencies and any possible coupling between cavities will be investigated.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR028
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Electro-Mechanical Modeling of the LCLS-II Superconducting Cavities

310

O. Kononenko, C. Adolphsen, Z. Li, T.O. Raubenheimer, C.H. Rivetta
SLAC, Menlo Park, California, USA

Funding: Work supported by the Department of Energy, Office of Science, Office of Basic Energy Science, under Contract No. DEAC0276SF00515
The 4 GeV LCLS-II superconducting linac will contain 280, 1.3 GHz TESLA-style cavities operated CW at 16 MV/m. Because of the low beam current, the cavity bandwidth will be fairly small, about 32 Hz, which makes the field stability sensitive to detuning from external vibrations and He pressure fluctuations. Piezo-electric actuators will be used to compensate for the detuning, which historically has been difficult at frequencies above a few Hz due to excitation of cavity mechanical resonances. To understand this interaction better, we have been doing extensive modeling of the cavities including mapping out the mechanical modes and computing their coupling to pressure changes, Lorentz forces and piezo actuator motion. One goal is to reproduce the measured detuning response of the piezo actuators up to 1 kHz, which is sensitive to how the cavities are constrained within a cryomodule. In this paper, we summarize these results and their implications for suppressing higher frequency detuning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOP106006

Export •

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

THPLR028

Simulation of Mechanical Oscillations in PIP-II Cryomodule Using ACE3P

910

L. Xiao, O. Kononenko, C.-K. Ng
SLAC, Menlo Park, California, USA

Funding: Work supported by the US DOE under contract DE-AC02-76SF00515.
The linac in the PIP-II project at Fermilab consists of different sections of superconducting rf (SRF) cavities that can accelerate the proton beams to 800 MeV. At the end of the linac is a section containing a number of HB (β = 0.92) cryomodules operating at 650 MHz, with each cryomodule consisting of six SRF cavities. Previous calculations have been carried out to determine the mechanical modes of a single cavity in the 650 MHz cryomodule. In this paper, the parallel code suite ACE3P is used to evaluate the mechanical modes for a string of SRF cavities in the 650 MHz cryomodule. The effects of multi cavities on the mechanical mode frequencies and any possible coupling between cavities will be investigated.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR028

Export •

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