IPAC2019 - List of Authors (Wang, S.)

Paper	Title	Page
MOPRB080	Transient Beam Loading and Mitigation in JLEIC Collider Rings	758
	J. Guo, R.A. Rimmer, H. Wang, S. Wang JLab, Newport News, Virginia, USA J.D. Fox Stanford University, Stanford, California, USA T. Mastoridis CalPoly, San Luis Obispo, California, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177, with additional support from U.S. DOE Award Number DE-SC-0019287 The Jefferson Lab Electron-Ion Collider (JLEIC) is an asymmetric high luminosity ring-ring collider proposed as the next major R&D facility for the nuclear physics community. Both of JLEIC’s electron and ion collider rings have high beam current with gaps serving the pur-poses of beam abort, ion clearing, etc. Such a time-varying beam loading in the RF cavities would generate modulation in cavity RF phase/voltage, causing cyclic shift of collision point and potential luminosity loss. We studied a few approaches to mitigate the RF phase modu-lation and IP shift, such as correcting the RF phase/voltage modulation with traditional LLRF feed-back, one-turn feedback (OTFB), or RF feedforward (FF); optimizing the bunch fill pattern to limit the RF phase/voltage modulation to a small fraction of the bunch trains in the collider ring; or matching the RF phase modulation in the two rings. The preliminary re-sults are discussed in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPRB080
About •	paper received ※ 23 May 2019 paper accepted ※ 24 May 2019 issue date ※ 21 June 2019
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WEPRB099	Status Update of a Harmonic Kicker Development for JLEIC	3047
	G.-T. Park, J. Guo, J. Henry, M. Marchlik, F. Marhauser, R.A. Rimmer, H. Wang, S. Wang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. An effort to develop the second prototype of the harmonic kicker for the Circulator Cooler Ring (CCR) of the Jefferson Lab Electron-Ion Collider (JLEIC) is under way. After beam dynamics studies and completion of a conceptual RF design of the kicker [1], further progress has been made toward the final mechanical design including the input power coupler (loop) design, tuner ports, multipacting studies. Furthermore, concerning the kicker’s compatibility with beam dynamics, the impact of RF multipole components was investigated and a scheme was developed to cancel out detrimental beam effects. 1. G. Park, et al, The Development of a New Fast Harmonic Kicker for the JLEIC Circulator Cooler Ring, TUPAL068, proceedings of IPAC 2018.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB099
About •	paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THXXPLM3	Experimental and Simulation Studies of Cooling of a Bunched Ion Beam in a Storage Ring by a Bunched Electron Beam
	Y. Zhang, S.V. Benson, A. Hutton, K. Jordan, T. Powers, R.A. Rimmer, M.F. Spata, A.V. Sy, H. Wang, S. Wang, H. Zhang JLab, Newport News, Virginia, USA J. Li, X.M. Ma, L.J. Mao, M.T. Tang, J.C. Yang, X.D. Yang, H. Zhao, H.W. Zhao IMP/CAS, Lanzhou, People’s Republic of China
	Cooling of a high energy ion beam is essential for future electron-ion colliders to reach high luminosity. It is critical to demonstrate experimentally cooling by a bunched electron beam and to benchmark the experimental data with simulations. Such experimental and simulation studies were carried out by a collaboration of Jefferson Lab and Institute of Modern Physics (IMP), utilizing a DC cooler at IMP. The thermionic gun of the DC cooler was modified by pulsing its grid voltage to produce cooling electron pulses in a pulse length range of 0.07 - 3.5 µs, with a 250 kHZ repetition frequency. The performed experiments clearly demonstrated cooling of a RF focused ion bunches by this pulsed electron beam. The momentum spread of cooled ion bunch has been reduced from ~2x10^-3 to ~6x10-4 in less than 0.5 second. The simulation results agree with the measurements qualitatively. In this paper, we present a brief overview of the experiments and also show the main experimental and simulation results.
	Slides THXXPLM3 [6.436 MB]
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Paper

Title

Page

Transient Beam Loading and Mitigation in JLEIC Collider Rings

758

J. Guo, R.A. Rimmer, H. Wang, S. Wang
JLab, Newport News, Virginia, USA
J.D. Fox
Stanford University, Stanford, California, USA
T. Mastoridis
CalPoly, San Luis Obispo, California, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177, with additional support from U.S. DOE Award Number DE-SC-0019287
The Jefferson Lab Electron-Ion Collider (JLEIC) is an asymmetric high luminosity ring-ring collider proposed as the next major R&D facility for the nuclear physics community. Both of JLEIC’s electron and ion collider rings have high beam current with gaps serving the pur-poses of beam abort, ion clearing, etc. Such a time-varying beam loading in the RF cavities would generate modulation in cavity RF phase/voltage, causing cyclic shift of collision point and potential luminosity loss. We studied a few approaches to mitigate the RF phase modu-lation and IP shift, such as correcting the RF phase/voltage modulation with traditional LLRF feed-back, one-turn feedback (OTFB), or RF feedforward (FF); optimizing the bunch fill pattern to limit the RF phase/voltage modulation to a small fraction of the bunch trains in the collider ring; or matching the RF phase modulation in the two rings. The preliminary re-sults are discussed in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPRB080

About •

paper received ※ 23 May 2019 paper accepted ※ 24 May 2019 issue date ※ 21 June 2019

Export •

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

WEPRB099

Status Update of a Harmonic Kicker Development for JLEIC

3047

G.-T. Park, J. Guo, J. Henry, M. Marchlik, F. Marhauser, R.A. Rimmer, H. Wang, S. Wang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
An effort to develop the second prototype of the harmonic kicker for the Circulator Cooler Ring (CCR) of the Jefferson Lab Electron-Ion Collider (JLEIC) is under way. After beam dynamics studies and completion of a conceptual RF design of the kicker [1], further progress has been made toward the final mechanical design including the input power coupler (loop) design, tuner ports, multipacting studies. Furthermore, concerning the kicker’s compatibility with beam dynamics, the impact of RF multipole components was investigated and a scheme was developed to cancel out detrimental beam effects.
1. G. Park, et al, The Development of a New Fast Harmonic Kicker for the JLEIC Circulator Cooler Ring, TUPAL068, proceedings of IPAC 2018.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB099

About •

paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

Export •

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

THXXPLM3

Experimental and Simulation Studies of Cooling of a Bunched Ion Beam in a Storage Ring by a Bunched Electron Beam

Y. Zhang, S.V. Benson, A. Hutton, K. Jordan, T. Powers, R.A. Rimmer, M.F. Spata, A.V. Sy, H. Wang, S. Wang, H. Zhang
JLab, Newport News, Virginia, USA
J. Li, X.M. Ma, L.J. Mao, M.T. Tang, J.C. Yang, X.D. Yang, H. Zhao, H.W. Zhao
IMP/CAS, Lanzhou, People’s Republic of China

Cooling of a high energy ion beam is essential for future electron-ion colliders to reach high luminosity. It is critical to demonstrate experimentally cooling by a bunched electron beam and to benchmark the experimental data with simulations. Such experimental and simulation studies were carried out by a collaboration of Jefferson Lab and Institute of Modern Physics (IMP), utilizing a DC cooler at IMP. The thermionic gun of the DC cooler was modified by pulsing its grid voltage to produce cooling electron pulses in a pulse length range of 0.07 - 3.5 µs, with a 250 kHZ repetition frequency. The performed experiments clearly demonstrated cooling of a RF focused ion bunches by this pulsed electron beam. The momentum spread of cooled ion bunch has been reduced from ~2x10^-3 to ~6x10-4 in less than 0.5 second. The simulation results agree with the measurements qualitatively. In this paper, we present a brief overview of the experiments and also show the main experimental and simulation results.

Slides THXXPLM3 [6.436 MB]

Export •

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