IPAC2018 - List of Authors (Holmes, D.)

Paper	Title	Page
TUPMF032	RF Conceptual Design of Normal Conducting Cavity for an eRHIC Rapid Cycling Synchrotron	1316
	B. P. Xiao, M. Blaskiewicz, J.M. Brennan, D. Holmes, K.S. Smith, T. Xin, A. Zaltsman BNL, Upton, Long Island, New York, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. The Rapid Cycling Synchrotron (RCS) for the eRHIC Ring-Ring design will provide on energy injection (up to 18 GeV) of high charge, polarized electron bunches to the eRHIC electron storage ring. The RF system comprises a large number of 563MHz fundamental cavities, providing up to 45MV per turn. The cavities will operate in pulsed mode with <20% duty factor, at a repetition rate of 1 Hz. In this paper we report the conceptual RF design of the cavity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF032
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WEPMF012	Power Requirement and Preliminary Coupler Design for the eRHIC Crab Cavity System	2394
	S. Verdú-Andrés, I. Ben-Zvi, D. Holmes, Q. Wu BNL, Upton, Long Island, New York, USA I. Ben-Zvi Stony Brook University, Stony Brook, USA
	Funding: Work supported by Brookhaven Science Associates LLC under contract no. DE-SC0012704 with the U.S. Department of Energy. Crab cavities are deflecting cavities operated in such a way that the bunch center is in synchronism with the zero-crossing kick voltage. In that case, beam loading is zero for an on-axis beam. The crab cavity system of the future electron-ion collider eRHIC will manipulate 275 GeV proton beams. At high energies, the beam offset can be as large as 2 mm (including mechanical and electrical offset tolerances). The beam loading resulting from such offset can greatly incur in large power requirements to the RF amplifier. The choice of external Q for the Fundamental Power Coupler (FPC) is critical to limit the power requirement to practical values. The loaded Q of the eRHIC crab cavities is mainly governed by the external Q of the FPC, so the external Q will also define the cavity bandwidth and thus the tuning requirements to counteract frequency transients from external perturbations. This paper discusses the choice of external Q for the FPC of the eRHIC crab cavities and introduces the design of a preliminary FPC antenna concept that would provide the appropriate external Q.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPMF012
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

RF Conceptual Design of Normal Conducting Cavity for an eRHIC Rapid Cycling Synchrotron

1316

B. P. Xiao, M. Blaskiewicz, J.M. Brennan, D. Holmes, K.S. Smith, T. Xin, A. Zaltsman
BNL, Upton, Long Island, New York, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
The Rapid Cycling Synchrotron (RCS) for the eRHIC Ring-Ring design will provide on energy injection (up to 18 GeV) of high charge, polarized electron bunches to the eRHIC electron storage ring. The RF system comprises a large number of 563MHz fundamental cavities, providing up to 45MV per turn. The cavities will operate in pulsed mode with <20% duty factor, at a repetition rate of 1 Hz. In this paper we report the conceptual RF design of the cavity.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF032

Export •

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

WEPMF012

Power Requirement and Preliminary Coupler Design for the eRHIC Crab Cavity System

2394

S. Verdú-Andrés, I. Ben-Zvi, D. Holmes, Q. Wu
BNL, Upton, Long Island, New York, USA
I. Ben-Zvi
Stony Brook University, Stony Brook, USA

Funding: Work supported by Brookhaven Science Associates LLC under contract no. DE-SC0012704 with the U.S. Department of Energy.
Crab cavities are deflecting cavities operated in such a way that the bunch center is in synchronism with the zero-crossing kick voltage. In that case, beam loading is zero for an on-axis beam. The crab cavity system of the future electron-ion collider eRHIC will manipulate 275 GeV proton beams. At high energies, the beam offset can be as large as 2 mm (including mechanical and electrical offset tolerances). The beam loading resulting from such offset can greatly incur in large power requirements to the RF amplifier. The choice of external Q for the Fundamental Power Coupler (FPC) is critical to limit the power requirement to practical values. The loaded Q of the eRHIC crab cavities is mainly governed by the external Q of the FPC, so the external Q will also define the cavity bandwidth and thus the tuning requirements to counteract frequency transients from external perturbations. This paper discusses the choice of external Q for the FPC of the eRHIC crab cavities and introduces the design of a preliminary FPC antenna concept that would provide the appropriate external Q.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPMF012

Export •

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