IPAC2018 - List of Authors (Yakovlev, V.P.)

Paper	Title	Page
THPAL034	Dynamic Tuner Development for Medium β Superconducting Elliptical Cavities	3709
SUSPL090	use link to see paper's listing under its alternate paper code
	C. Contreras-Martinez, P.N. Ostroumov FRIB, East Lansing, USA E. Borissov, S. Cheban, Y.M. Pischalnikov, V.P. Yakovlev, J.C. Yun Fermilab, Batavia, Illinois, USA
	Funding: Work supported by U.S. DOE SCGSR program under contract number DE-SC0014664, Michigan State University, and Fermi Research Alliance under contract N. DEAC02-07CH11959 with the U.S. DOE The Facility for Rare Isotope Beams (FRIB) is developing a 5-cell 644 MHz β_opt=0.65 elliptical cavity for a future linac energy upgrade to 400 MeV/u for the heaviest uranium ions. Superconducting elliptical cavities operated in continuous wave, such as the ones for FRIB, are prone to microphonics which can excite mechanical modes of the cavities. It has been shown that the detuning due to microphonics can be mitigated with the use of piezo actuators (fast tuner) as opposed to the costly option of increasing the input RF power. The FRIB slow/fast dynamic tuner will be based on the Fermilab experience with similar tuners like those developed for the linac coherent light source (LCLS) II and proton improvement plan (PIP) II. This paper will present the results of tuner properties on the bench.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL034
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THPAL035	Design of β=0.65, 5 Cells, 644 MHz Elliptical Cavity for FRIB Upgrade	3712
	M. Xu, C. Compton, C. Contreras-Martinez, W. Hartung, S.H. Kim, S.J. Miller, P.N. Ostroumov, A.S. Plastun, J.T. Popielarski, L. Popielarski, M.A. Reaume, K. Saito, A. Taylor, J. Wei, T. Xu, Q. Zhao FRIB, East Lansing, USA I.V. Gonin, T.N. Khabiboulline, V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	Funding: Work supported by the U.S. DOE Office of Science under Cooperative Agreement DE-SC0000661 and the NSF under Cooperative Agreement PHY-1102511, the State of Michigan and Michigan State University. The superconducting (SC) linac of the Facility for Rare Isotope Beams (FRIB) under construction will deliver 200 MeV/u, 400 kW beam to the target for producing rare isotopes at Michigan State of University (MSU). For further beam energy upgrade, we have designed the β = 0.65, 5 cells, 644 MHz elliptical cavity. The beam energy can be upgraded to 400 MeV/u by installing 11 cryomodules to the available space in the FRIB tunnel.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL035
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THPAL038	Phase Grouping of Larmor Electrons by a Synchronous Wave in Controlled Magnetrons	3723
	G.M. Kazakevich, R.P. Johnson Muons, Inc, Illinois, USA V.A. Lebedev, V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	A simplified analytical model based on the charge drift approximation has been developed. It considers the resonant interaction of the synchronous wave with the flow of Larmor electrons in a magnetron. The model predicts stable coherent generation of the tube above and below the threshold of self-excitation. This occurs if the magnetron is driven by a sufficient resonant injected signal (up to -10 dB). The model substantiates precise stability, high efficiency and low noise at the range of the magnetron power control over 10 dB by variation of the magnetron current. The model and the verifying experiments with 2.45 GHz, 1 kW magnetrons are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL038
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THPAL039	Improved Magnetron Stability and Reduced Noise in Efficient Transmitters for Superconducting Accelerators	3726
	G.M. Kazakevich, R.P. Johnson Muons, Inc, Illinois, USA V.A. Lebedev, V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	State of the art high-current superconducting accelerators require efficient RF sources with a fast dynamic phase and power control. This allows for compensation of the phase and amplitude deviations of the accelerating volt-age in the Superconducting RF (SRF) cavities caused by microphonics, etc. Efficient magnetron transmitters with fast phase and power control are attractive RF sources for this application. They are more cost effective than traditional RF sources such as klystrons, IOTs and solid-state amplifiers used with large scale accelerator projects. However, unlike traditional RF sources, controlled magnetrons operate as forced oscillators. Study of the impact of the controlling signal on magnetron stability, noise and efficiency is therefore important. This paper discusses experiments with 2.45 GHz, 1 kW tubes and verifies our analytical model which is based on the charge drift approximation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL039
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Paper

Title

Page

THPAL034

Dynamic Tuner Development for Medium β Superconducting Elliptical Cavities

3709

SUSPL090

use link to see paper's listing under its alternate paper code

C. Contreras-Martinez, P.N. Ostroumov
FRIB, East Lansing, USA
E. Borissov, S. Cheban, Y.M. Pischalnikov, V.P. Yakovlev, J.C. Yun
Fermilab, Batavia, Illinois, USA

Funding: Work supported by U.S. DOE SCGSR program under contract number DE-SC0014664, Michigan State University, and Fermi Research Alliance under contract N. DEAC02-07CH11959 with the U.S. DOE
The Facility for Rare Isotope Beams (FRIB) is developing a 5-cell 644 MHz β_opt=0.65 elliptical cavity for a future linac energy upgrade to 400 MeV/u for the heaviest uranium ions. Superconducting elliptical cavities operated in continuous wave, such as the ones for FRIB, are prone to microphonics which can excite mechanical modes of the cavities. It has been shown that the detuning due to microphonics can be mitigated with the use of piezo actuators (fast tuner) as opposed to the costly option of increasing the input RF power. The FRIB slow/fast dynamic tuner will be based on the Fermilab experience with similar tuners like those developed for the linac coherent light source (LCLS) II and proton improvement plan (PIP) II. This paper will present the results of tuner properties on the bench.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL034

Export •

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

THPAL035

Design of β=0.65, 5 Cells, 644 MHz Elliptical Cavity for FRIB Upgrade

3712

M. Xu, C. Compton, C. Contreras-Martinez, W. Hartung, S.H. Kim, S.J. Miller, P.N. Ostroumov, A.S. Plastun, J.T. Popielarski, L. Popielarski, M.A. Reaume, K. Saito, A. Taylor, J. Wei, T. Xu, Q. Zhao
FRIB, East Lansing, USA
I.V. Gonin, T.N. Khabiboulline, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

Funding: Work supported by the U.S. DOE Office of Science under Cooperative Agreement DE-SC0000661 and the NSF under Cooperative Agreement PHY-1102511, the State of Michigan and Michigan State University.
The superconducting (SC) linac of the Facility for Rare Isotope Beams (FRIB) under construction will deliver 200 MeV/u, 400 kW beam to the target for producing rare isotopes at Michigan State of University (MSU). For further beam energy upgrade, we have designed the β = 0.65, 5 cells, 644 MHz elliptical cavity. The beam energy can be upgraded to 400 MeV/u by installing 11 cryomodules to the available space in the FRIB tunnel.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL035

Export •

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

THPAL038

Phase Grouping of Larmor Electrons by a Synchronous Wave in Controlled Magnetrons

3723

G.M. Kazakevich, R.P. Johnson
Muons, Inc, Illinois, USA
V.A. Lebedev, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

A simplified analytical model based on the charge drift approximation has been developed. It considers the resonant interaction of the synchronous wave with the flow of Larmor electrons in a magnetron. The model predicts stable coherent generation of the tube above and below the threshold of self-excitation. This occurs if the magnetron is driven by a sufficient resonant injected signal (up to -10 dB). The model substantiates precise stability, high efficiency and low noise at the range of the magnetron power control over 10 dB by variation of the magnetron current. The model and the verifying experiments with 2.45 GHz, 1 kW magnetrons are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL038

Export •

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

THPAL039

Improved Magnetron Stability and Reduced Noise in Efficient Transmitters for Superconducting Accelerators

3726

G.M. Kazakevich, R.P. Johnson
Muons, Inc, Illinois, USA
V.A. Lebedev, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

State of the art high-current superconducting accelerators require efficient RF sources with a fast dynamic phase and power control. This allows for compensation of the phase and amplitude deviations of the accelerating volt-age in the Superconducting RF (SRF) cavities caused by microphonics, etc. Efficient magnetron transmitters with fast phase and power control are attractive RF sources for this application. They are more cost effective than traditional RF sources such as klystrons, IOTs and solid-state amplifiers used with large scale accelerator projects. However, unlike traditional RF sources, controlled magnetrons operate as forced oscillators. Study of the impact of the controlling signal on magnetron stability, noise and efficiency is therefore important. This paper discusses experiments with 2.45 GHz, 1 kW tubes and verifies our analytical model which is based on the charge drift approximation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL039

Export •

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