COOL2015 - List of Keywords (cavity)

Paper	Title	Other Keywords	Page
MOPF13	Taper and Tuner Scheme of a Multi-Frequency Cavity for the Fast Kicker Resonator in MEIC Electron Circular Cooler Ring	electron, kicker, simulation, impedance	63
	Y.L. Huang IMP/CAS, Lanzhou, People's Republic of China R.A. Rimmer, H. Wang, S. Wang JLab, Newport News, Virginia, USA
	An ultra-fast harmonic kicker consisted of normal conducting resonators with high transverse shunt impedance thus less RF power consumption was designed for the proposed Medium energy Electron Ion Collider (MEIC). In the prototype design, four quarter wave resonator (QWR) based deflecting cavities are used to generate ten cosine harmonic waveforms, the electron bunches passing through these cavities will experience an integral effect of all the harmonic fields, thus every 10th bunch in a continues bunch train of 10th harmonic bunch frequency will be kicked while all the other bunches un-kicked. Ten harmonic waves are distributed in the four cavities with the proportion of 5:3:1:1. For the multi-frequency cavities, a great challenge is to tune each harmonic to be exact frequency. In this paper, the taper and tuning scheme for the 5-modes cavity is presented. Five taper points in the inner conductor are chosen to make the five frequencies to be odd harmonics. Five stub tuners on the outer conductor are used to tune every harmonic back to its target frequency from the manufacturing errors. Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
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TUWAUD03	Study of Helical Cooling Channel for Intense Muon Source	plasma, simulation, solenoid, emittance	72
	K. Yonehara Fermilab, Batavia, Illinois, USA Y.S. Derbenev JLab, Newport News, Virginia, USA R.P. Johnson Muons, Inc, Illinois, USA
	Linear beam dynamics of muons in a helical cooling channel is non-trivial. Betatron oscillation in the channel is induced by coupling of motions in xyz-planes. As a result, the analytic eigen values are very complicated. The cooling decrements are controlled by tuning coupling strength. The helical dynamic parameters are translated into the conventional accelerator physics term. Non-linear dynamics in the helical channel is studied by using the conventional accelerator technique. The beam-plasma interaction in a high-pressure hydrogen gas-filled RF cavity is a new physics process and important to design the cooling channel. Machine development of helical beam elements is also shown in this presentation.
	Slides TUWAUD03 [6.220 MB]
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THWCR04	RF Technologies for Ionization Cooling Channels	vacuum, electron, plasma, ion	145
	B.T. Freemire, Y. Torun IIT, Chicago, Illinois, USA D.L. Bowring, A. Moretti, A.V. Tollestrup, K. Yonehara Fermilab, Batavia, Illinois, USA A.V. Kochemirovskiy University of Chicago, Chicago, Illinois, USA D. Stratakis BNL, Upton, Long Island, New York, USA
	Funding: Fermilab Research Alliance, LLC under Contract No. DE-AC02-07CH11359 Ionization cooling is the preferred method of cooling a muon beam for the purposes of a bright muon source. This process works by sending a muon beam through an absorbing material and replacing the lost longitudinal momentum with radio frequency (RF) cavities. To maximize the effect of cooling, a small optical beta function is required at the locations of the absorbers. Strong focusing is therefore required, and as a result normal conducting RF cavities must operate in external magnetic fields on the order of 10 Tesla. Vacuum and high pressure gas filled RF test cells have been studied at the MuCool Test Area at Fermilab. Methods for mitigating breakdown in both test cells, as well as the effect of plasma loading in the gas filled test cell have been investigated. The results of these tests, as well as the current status of the two leading muon cooling channel designs, will be presented.
	Slides THWCR04 [46.592 MB]
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Paper

Title

Other Keywords

Page

MOPF13

Taper and Tuner Scheme of a Multi-Frequency Cavity for the Fast Kicker Resonator in MEIC Electron Circular Cooler Ring

electron, kicker, simulation, impedance

63

Y.L. Huang
IMP/CAS, Lanzhou, People's Republic of China
R.A. Rimmer, H. Wang, S. Wang
JLab, Newport News, Virginia, USA

An ultra-fast harmonic kicker consisted of normal conducting resonators with high transverse shunt impedance thus less RF power consumption was designed for the proposed Medium energy Electron Ion Collider (MEIC). In the prototype design, four quarter wave resonator (QWR) based deflecting cavities are used to generate ten cosine harmonic waveforms, the electron bunches passing through these cavities will experience an integral effect of all the harmonic fields, thus every 10th bunch in a continues bunch train of 10th harmonic bunch frequency will be kicked while all the other bunches un-kicked. Ten harmonic waves are distributed in the four cavities with the proportion of 5:3:1:1. For the multi-frequency cavities, a great challenge is to tune each harmonic to be exact frequency. In this paper, the taper and tuning scheme for the 5-modes cavity is presented. Five taper points in the inner conductor are chosen to make the five frequencies to be odd harmonics. Five stub tuners on the outer conductor are used to tune every harmonic back to its target frequency from the manufacturing errors.
Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.

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TUWAUD03

Study of Helical Cooling Channel for Intense Muon Source

plasma, simulation, solenoid, emittance

72

K. Yonehara
Fermilab, Batavia, Illinois, USA
Y.S. Derbenev
JLab, Newport News, Virginia, USA
R.P. Johnson
Muons, Inc, Illinois, USA

Linear beam dynamics of muons in a helical cooling channel is non-trivial. Betatron oscillation in the channel is induced by coupling of motions in xyz-planes. As a result, the analytic eigen values are very complicated. The cooling decrements are controlled by tuning coupling strength. The helical dynamic parameters are translated into the conventional accelerator physics term. Non-linear dynamics in the helical channel is studied by using the conventional accelerator technique. The beam-plasma interaction in a high-pressure hydrogen gas-filled RF cavity is a new physics process and important to design the cooling channel. Machine development of helical beam elements is also shown in this presentation.

Slides TUWAUD03 [6.220 MB]

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

THWCR04

RF Technologies for Ionization Cooling Channels

vacuum, electron, plasma, ion

145

B.T. Freemire, Y. Torun
IIT, Chicago, Illinois, USA
D.L. Bowring, A. Moretti, A.V. Tollestrup, K. Yonehara
Fermilab, Batavia, Illinois, USA
A.V. Kochemirovskiy
University of Chicago, Chicago, Illinois, USA
D. Stratakis
BNL, Upton, Long Island, New York, USA

Funding: Fermilab Research Alliance, LLC under Contract No. DE-AC02-07CH11359
Ionization cooling is the preferred method of cooling a muon beam for the purposes of a bright muon source. This process works by sending a muon beam through an absorbing material and replacing the lost longitudinal momentum with radio frequency (RF) cavities. To maximize the effect of cooling, a small optical beta function is required at the locations of the absorbers. Strong focusing is therefore required, and as a result normal conducting RF cavities must operate in external magnetic fields on the order of 10 Tesla. Vacuum and high pressure gas filled RF test cells have been studied at the MuCool Test Area at Fermilab. Methods for mitigating breakdown in both test cells, as well as the effect of plasma loading in the gas filled test cell have been investigated. The results of these tests, as well as the current status of the two leading muon cooling channel designs, will be presented.

Slides THWCR04 [46.592 MB]

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