SRF2017 - List of Authors (Zaplatin, E.N.)

Paper	Title	Page
TUPB020	Microphonics Passive Damping	423
	E.N. Zaplatin FZJ, Jülich, Germany A. Kanareykin Euclid TechLabs, LLC, Solon, Ohio, USA V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	Different types of external loads on the resonator walls predetermine the main working conditions of the SRF cavities. The most important of them are very high electromagnetic fields that result in strong Lorentz forces and the pressure on cavity walls from the helium tank that also deforms the cavity shape. For pulsed operation, the Lorentz forces usually play the decisive role for the cavity design. For CW operation, the liquid helium vessel pressure instability even for 2K operations is the source of large microphonics. All deformations resulting from any type of external loads on cavity walls lead to shifts in the working RF frequency in the range of hundreds of kHz. Taking into account high Q-factor of SC cavities such a large frequency shift takes the cavity out of operation. Here we present and discuss the achievements and problems of microphonics passive damping in different type SRF cavities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB021	First Considerations on HZB High Frequency Elliptical Resonator Stiffening	428
	E.N. Zaplatin FZJ, Jülich, Germany H.-W. Glock, J. Knobloch, A. Neumann, A.V. Vélez HZB, Berlin, Germany
	There are two projects that currently are under development and construction at HZB which utilize high frequency elliptical resonators ' Energy Recovery Linac Prototype (BERLinPro, 7-cell, 1300 MHz, β=1) and BESSY Variable pulse-length Storage Ring (VSR, 5-cell, 1500/1750 MHz, β=1). A critical issue of both projects is small effective beam loading in cavities operating at high CW fields (Eacc of 20 MV/m) with a narrow band width. This necessitates precise tuning and therefore good compensation of microphonics and coupled Lorentz-force detuning driven instabilities. Here we present a conceptual study of an integrated SRF resonator and helium vessel structure design to ensure a reduced resonance frequency dependence on pressure and Lorentz forces to minimize their impact on the accelerating field profile.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Microphonics Passive Damping

423

E.N. Zaplatin
FZJ, Jülich, Germany
A. Kanareykin
Euclid TechLabs, LLC, Solon, Ohio, USA
V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

Different types of external loads on the resonator walls predetermine the main working conditions of the SRF cavities. The most important of them are very high electromagnetic fields that result in strong Lorentz forces and the pressure on cavity walls from the helium tank that also deforms the cavity shape. For pulsed operation, the Lorentz forces usually play the decisive role for the cavity design. For CW operation, the liquid helium vessel pressure instability even for 2K operations is the source of large microphonics. All deformations resulting from any type of external loads on cavity walls lead to shifts in the working RF frequency in the range of hundreds of kHz. Taking into account high Q-factor of SC cavities such a large frequency shift takes the cavity out of operation. Here we present and discuss the achievements and problems of microphonics passive damping in different type SRF cavities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB020

Export •

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

TUPB021

First Considerations on HZB High Frequency Elliptical Resonator Stiffening

428

E.N. Zaplatin
FZJ, Jülich, Germany
H.-W. Glock, J. Knobloch, A. Neumann, A.V. Vélez
HZB, Berlin, Germany

There are two projects that currently are under development and construction at HZB which utilize high frequency elliptical resonators ' Energy Recovery Linac Prototype (BERLinPro, 7-cell, 1300 MHz, β=1) and BESSY Variable pulse-length Storage Ring (VSR, 5-cell, 1500/1750 MHz, β=1). A critical issue of both projects is small effective beam loading in cavities operating at high CW fields (Eacc of 20 MV/m) with a narrow band width. This necessitates precise tuning and therefore good compensation of microphonics and coupled Lorentz-force detuning driven instabilities. Here we present a conceptual study of an integrated SRF resonator and helium vessel structure design to ensure a reduced resonance frequency dependence on pressure and Lorentz forces to minimize their impact on the accelerating field profile.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB021

Export •

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