IPAC2016 - List of Authors (Bachimanchi, R.)

Paper	Title	Page
WEPOR042	LLRF Control of High Loaded-Q Cavities for the LCLS-II	2765
	C. Serrano, L.R. Doolittle, G. Huang, A. Ratti LBNL, Berkeley, California, USA S. Babel, M. Boyes, B. Hong SLAC, Menlo Park, California, USA R. Bachimanchi, C. Hovater JLab, Newport News, Virginia, USA B.E. Chase, E. Cullerton, J. Einstein Fermilab, Batavia, Illinois, USA
	Funding: This work was supported by the LCLS-II Project and the U.S. Department of Energy, Contract DE-AC02-76SF00515 The SLAC National Accelerator Laboratory is planning an upgrade (LCLS-II) to the Linear Coherent Light Source with a 4 GeV CW Superconducting Radio Frequency (SCRF) linac. The nature of the machine places stringent requirements in the Low-Level RF (LLRF) system, expected to control the cavity fields within 0.01 degrees in phase and 0.01% in amplitude, which is equivalent to a longitudinal motion of the cavity structure in the nanometer range. This stability has been achieved in the past but never for hundreds of superconducting cavities in Continuous-Wave (CW) operation. The difficulty resides in providing the ability to reject disturbances from the cryomodule, which is incompletely known as it depends on the cryomodule structure itself (currently under development at JLab and Fermilab) and the harsh accelerator environment. Previous experience in the field and an extrapolation to the cavity design parameters (relatively high Q_Lc≈ 4×10⁷ , implying a half-bandwidth of around 16 Hz) suggest the use of strong RF feedback to reject the projected noise disturbances, which in turn demands careful engineering of the entire system.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR042
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Paper

Title

Page

LLRF Control of High Loaded-Q Cavities for the LCLS-II

2765

C. Serrano, L.R. Doolittle, G. Huang, A. Ratti
LBNL, Berkeley, California, USA
S. Babel, M. Boyes, B. Hong
SLAC, Menlo Park, California, USA
R. Bachimanchi, C. Hovater
JLab, Newport News, Virginia, USA
B.E. Chase, E. Cullerton, J. Einstein
Fermilab, Batavia, Illinois, USA

Funding: This work was supported by the LCLS-II Project and the U.S. Department of Energy, Contract DE-AC02-76SF00515
The SLAC National Accelerator Laboratory is planning an upgrade (LCLS-II) to the Linear Coherent Light Source with a 4 GeV CW Superconducting Radio Frequency (SCRF) linac. The nature of the machine places stringent requirements in the Low-Level RF (LLRF) system, expected to control the cavity fields within 0.01 degrees in phase and 0.01% in amplitude, which is equivalent to a longitudinal motion of the cavity structure in the nanometer range. This stability has been achieved in the past but never for hundreds of superconducting cavities in Continuous-Wave (CW) operation. The difficulty resides in providing the ability to reject disturbances from the cryomodule, which is incompletely known as it depends on the cryomodule structure itself (currently under development at JLab and Fermilab) and the harsh accelerator environment. Previous experience in the field and an extrapolation to the cavity design parameters (relatively high Q_Lc≈ 4×10⁷ , implying a half-bandwidth of around 16 Hz) suggest the use of strong RF feedback to reject the projected noise disturbances, which in turn demands careful engineering of the entire system.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR042

Export •

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