LINAC2018 - List of Authors (Higgins, H.)

Paper	Title	Page
MOPO115	CEBAF Photo Gun RF System	236
	T. E. Plawski, R. Bachimanchi, M. Diaz, H. Higgins, C. Hovater, C.I. Mounts, D.J. Seidman JLab, Newport News, Virginia, USA
	Funding: Authored by JSA, LLC under U.S. DOE Contract DE-AC05- 06OR23177 and DE-SC0005264. During the CEBAF 12 GeV Upgrade at Jefferson Lab, a fourth experimental hall, ’D’, was added to the existing three halls. To produce four beams and deliver them to all halls concurrently requires new frequencies and a new timing pattern of the electron bunches. Since a photo-gun is used to produce electron bunches, the gun’s drive laser pulses need to be synchronized with the required bunch rate frequencies of 499 MHz or 249.5 MHz. To meet these new operational requirements, the new LLRF system has been proposed. Very specific requirements (dual frequency operation) on one side and the simple RF drive mode operation on the other imply the use of a commercial off-the-shelf digital platform rather than a system typical for RF cavity field control. We have chosen the Texas Instruments FPGA board along with a high-speed 8-Channel, 14-Bit board, and a 4-Channel, 16-Bit board. The DAC board includes the clock generator for clocking ADCs, DACs and the FPGA. The complete Gun Laser LLRF system has been designed, built, and recently commissioned in the CEBAF Injector. This paper will detail the design and report on commissioning activities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO115
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

CEBAF Photo Gun RF System

236

T. E. Plawski, R. Bachimanchi, M. Diaz, H. Higgins, C. Hovater, C.I. Mounts, D.J. Seidman
JLab, Newport News, Virginia, USA

Funding: Authored by JSA, LLC under U.S. DOE Contract DE-AC05- 06OR23177 and DE-SC0005264.
During the CEBAF 12 GeV Upgrade at Jefferson Lab, a fourth experimental hall, ’D’, was added to the existing three halls. To produce four beams and deliver them to all halls concurrently requires new frequencies and a new timing pattern of the electron bunches. Since a photo-gun is used to produce electron bunches, the gun’s drive laser pulses need to be synchronized with the required bunch rate frequencies of 499 MHz or 249.5 MHz. To meet these new operational requirements, the new LLRF system has been proposed. Very specific requirements (dual frequency operation) on one side and the simple RF drive mode operation on the other imply the use of a commercial off-the-shelf digital platform rather than a system typical for RF cavity field control. We have chosen the Texas Instruments FPGA board along with a high-speed 8-Channel, 14-Bit board, and a 4-Channel, 16-Bit board. The DAC board includes the clock generator for clocking ADCs, DACs and the FPGA. The complete Gun Laser LLRF system has been designed, built, and recently commissioned in the CEBAF Injector. This paper will detail the design and report on commissioning activities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO115

About •

paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

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