SRF2021 - List of Authors (Kostin, R.A.)

Paper	Title	Page
MOPTEV009	A Method for In-Situ Q₀ Measurements of High-Quality SRF Resonators	221
	S.V. Kuzikov, P.V. Avrakhov, C.-J. Jing, R.A. Kostin, Y. Zhao Euclid TechLabs, Solon, Ohio, USA C.-J. Jing, C.-J. Jing ANL, Lemont, Illinois, USA C.-J. Jing, R.A. Kostin Euclid Beamlabs, Bolingbrook, USA R.A. Kostin, V.P. Yakovlev Fermilab, Batavia, Illinois, USA T. Powers, R.A. Rimmer JLab, Newport News, Virginia, USA
	Funding: The work was supported in the part by DoE SBIR grant #DE-SC0019687. Accelerator projects such as LCLS-II naturally require low-loss superconducting (SRF) cavities. Due to strong demand for improving intrinsic quality factor (Q₀), importance of accurate cavity characterization increases. We propose a method to measure Q₀ in situ for an SRF resonator installed in its cryogenic module and connected with a RF feed source via a fixed RF coupler. The method exploits measurements of a response for an SRF resonator fed by an amplitude-modulated signal. Such a signal can be synthesized as a beat-wave composed of two frequencies that are close to the resonant frequency. Analyzing the envelope of the reflected signal, one can find the difference in reflection for the chosen frequencies and use them to compute the intrinsic Q. We also develop the methodology to carry out measurements of Q₀ at the nominal cavity operating voltage. We verified our method in experiments with a room temperature copper resonator and with two SRF resonators including Fermilab’s 650 MHz cavity and JLab’s 1500 MHz cavity.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV009
About •	Received ※ 15 June 2021 — Revised ※ 26 August 2021 — Accepted ※ 19 February 2022 — Issue date ※ 06 April 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

A Method for In-Situ Q₀ Measurements of High-Quality SRF Resonators

221

S.V. Kuzikov, P.V. Avrakhov, C.-J. Jing, R.A. Kostin, Y. Zhao
Euclid TechLabs, Solon, Ohio, USA
C.-J. Jing, C.-J. Jing
ANL, Lemont, Illinois, USA
C.-J. Jing, R.A. Kostin
Euclid Beamlabs, Bolingbrook, USA
R.A. Kostin, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA
T. Powers, R.A. Rimmer
JLab, Newport News, Virginia, USA

Funding: The work was supported in the part by DoE SBIR grant #DE-SC0019687.
Accelerator projects such as LCLS-II naturally require low-loss superconducting (SRF) cavities. Due to strong demand for improving intrinsic quality factor (Q₀), importance of accurate cavity characterization increases. We propose a method to measure Q₀ in situ for an SRF resonator installed in its cryogenic module and connected with a RF feed source via a fixed RF coupler. The method exploits measurements of a response for an SRF resonator fed by an amplitude-modulated signal. Such a signal can be synthesized as a beat-wave composed of two frequencies that are close to the resonant frequency. Analyzing the envelope of the reflected signal, one can find the difference in reflection for the chosen frequencies and use them to compute the intrinsic Q. We also develop the methodology to carry out measurements of Q₀ at the nominal cavity operating voltage. We verified our method in experiments with a room temperature copper resonator and with two SRF resonators including Fermilab’s 650 MHz cavity and JLab’s 1500 MHz cavity.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV009

About •

Received ※ 15 June 2021 — Revised ※ 26 August 2021 — Accepted ※ 19 February 2022 — Issue date ※ 06 April 2022

Cite •

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