ICALEPCS2023 - List of Authors (Johnson, T.K.)

Paper	Title	Page
WE1BCO07	The LCLS-II Precision Timing Control System	966
	T.K. Johnson, M.C. Browne, C.B. Pino SLAC, Menlo Park, California, USA
	The LCLS-II precision timing system is responsible for the synchronization of optical lasers with the LCLS-II XFEL. The system uses both RF and optical references for synchronization. In contrast to previous systems used at LCLS the optical lasers are shared resources, and must be managed during operations. The timing system consists of three primary functionalities: RF reference distribution, optical reference distribution, and a phase-locked loop (PLL). This PLL may use either the RF or the optical reference as a feedback source. The RF allows for phase comparisons over a relatively wide range, albeit with limited resolution, while the optical reference enables very fine phase comparison (down to attoseconds), but with limited operational range. These systems must be managed using high levels of automation. Much of this automation is done via high-level applications developed in EPICS. The beamline users are presented with relatively simple interfaces that streamline operation and abstract much of the system complexity away. The system provides both PyDM GUIs as well as python interfaces to enable time delay scanning in the LCLS-II DAQ.
	Slides WE1BCO07 [3.734 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS2023-WE1BCO07
About •	Received ※ 06 November 2023 — Revised ※ 09 November 2023 — Accepted ※ 14 December 2023 — Issued ※ 20 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TH2BCO03	The LCLS-II Experiment Control System	1172
	T.A. Wallace, D.L. Flath, M. Ghaly, T.K. Johnson, K.R. Lauer, Z.L. Lentz, R.S. Tang-Kong, J. Yin SLAC, Menlo Park, California, USA
	Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515. The Linac Coherent Light Source (LCLS) has been undergoing upgrades for several years now through at least two separate major projects: LCLS-II a DOE 403.13b project responsible for upgrading the accelerator, undulators and some front-end beam delivery systems, and the LCLS-II Strategic Initiative or L2SI project which assumed responsibility for upgrading the experiment endstations to fully utilize the new XFEL machine capabilities to be delivered by LCLS-II. Both projects included scope to design, install and commission a control system prepared to handle the risks associated with the tenfold increase in beam power we will eventually achieve. This paper provides an overview of the new control system architecture from the LCLS-II and L2SI projects and status of its commissioning.
	Slides TH2BCO03 [2.700 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS2023-TH2BCO03
About •	Received ※ 04 November 2023 — Accepted ※ 11 December 2023 — Issued ※ 16 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

The LCLS-II Precision Timing Control System

966

T.K. Johnson, M.C. Browne, C.B. Pino
SLAC, Menlo Park, California, USA

The LCLS-II precision timing system is responsible for the synchronization of optical lasers with the LCLS-II XFEL. The system uses both RF and optical references for synchronization. In contrast to previous systems used at LCLS the optical lasers are shared resources, and must be managed during operations. The timing system consists of three primary functionalities: RF reference distribution, optical reference distribution, and a phase-locked loop (PLL). This PLL may use either the RF or the optical reference as a feedback source. The RF allows for phase comparisons over a relatively wide range, albeit with limited resolution, while the optical reference enables very fine phase comparison (down to attoseconds), but with limited operational range. These systems must be managed using high levels of automation. Much of this automation is done via high-level applications developed in EPICS. The beamline users are presented with relatively simple interfaces that streamline operation and abstract much of the system complexity away. The system provides both PyDM GUIs as well as python interfaces to enable time delay scanning in the LCLS-II DAQ.

Slides WE1BCO07 [3.734 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS2023-WE1BCO07

About •

Received ※ 06 November 2023 — Revised ※ 09 November 2023 — Accepted ※ 14 December 2023 — Issued ※ 20 December 2023

Cite •

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

TH2BCO03

The LCLS-II Experiment Control System

1172

T.A. Wallace, D.L. Flath, M. Ghaly, T.K. Johnson, K.R. Lauer, Z.L. Lentz, R.S. Tang-Kong, J. Yin
SLAC, Menlo Park, California, USA

Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515.
The Linac Coherent Light Source (LCLS) has been undergoing upgrades for several years now through at least two separate major projects: LCLS-II a DOE 403.13b project responsible for upgrading the accelerator, undulators and some front-end beam delivery systems, and the LCLS-II Strategic Initiative or L2SI project which assumed responsibility for upgrading the experiment endstations to fully utilize the new XFEL machine capabilities to be delivered by LCLS-II. Both projects included scope to design, install and commission a control system prepared to handle the risks associated with the tenfold increase in beam power we will eventually achieve. This paper provides an overview of the new control system architecture from the LCLS-II and L2SI projects and status of its commissioning.

Slides TH2BCO03 [2.700 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS2023-TH2BCO03

About •

Received ※ 04 November 2023 — Accepted ※ 11 December 2023 — Issued ※ 16 December 2023

Cite •

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