ICALEPCS2019 - List of Authors (Fisher, A.S.)

Paper	Title	Page
WEPHA044	Upgrade of the Bunch Length and Bunch Charge Control Systems for the New SLAC Free Electron Laser	1185
	M.P. Donadio, A.S. Fisher, L. Sapozhnikov SLAC, Menlo Park, California, USA
	In 2019 SLAC is building a new linear accelerator based on superconducting niobium cavities. The first one, now called the copper linac, could generate 120 electron bunches per second. The new one, called superconducting linac, will generate 1 million per second, bringing some challenges to many devices along with the accelerator. Most of them receive sensors and actuators in a VME-based Platform with its control running in software, with RTEMS as OS. This is feasible for 120 Hz, but not for 1 MHz. The new control hardware is ATCA-based Platform, that has carrier boards with FPGA connected to servers running Embedded real-time Linux OS, forming the High-Performance System (HPS). Instead of having all the new architecture installed at the accelerator and tested on the go, SLAC used the strategy of testing the systems in the copper linac, to have them ready to use in the superconducting linac in what was called the Mission Readiness Program. The Bunch Length System and the Bunch Charge System are examples of devices of this program. Both systems were tested in the copper linac at 120 Hz, with excellent results. The next step is to test them at the superconducting linac, at 1 MHz.
	Poster WEPHA044 [1.308 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2019-WEPHA044
About •	paper received ※ 28 September 2019 paper accepted ※ 09 October 2019 issue date ※ 30 August 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THCPR07	Electronics for LCLS-II Beam Containment System Loss Monitors	1641
	R.A. Kadyrov, C.I. Clarke, A.S. Fisher, M. Petree, C. Yee SLAC, Menlo Park, California, USA
	LCLS-II is a new FEL which is under construction at SLAC National Accelerator Laboratory. Its superconducting electron linac is able to produce up to 1.2 MW of beam power. In event of electron beam loss, radiation levels can exceed allowed levels outside thin shielding originally built for a lower energy LCLS linac. Beam Containment System (BCS) loss monitors are employed to detect the radiation and shut-off the beam within 200 µs, limit the radiation dose in occupied areas and minimize damage to the equipment. sCVD single-crystal diamond particle detectors are used as Point Beam Loss Monitors (PBLM) to detect losses locally. Fiber optics is selected as Long Beam Loss Monitor (LBLM). PMT at downstream end of the LBLM detects light produced by Cherenkov radiation. LBLM provides continuous coverage along electron beam path from the gun to the dump. Unified set of electronics is designed to integrate the charge from PMT or sCVD, compare the loss with predefined threshold and generate the fault if the limit is breached. Continuous self-checking is implemented for both types of sensors. Challenges in electronics design, cable selection and self-checking implementation are discussed.
	Slides THCPR07 [1.204 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2019-THCPR07
About •	paper received ※ 27 September 2019 paper accepted ※ 09 October 2019 issue date ※ 30 August 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Upgrade of the Bunch Length and Bunch Charge Control Systems for the New SLAC Free Electron Laser

1185

M.P. Donadio, A.S. Fisher, L. Sapozhnikov
SLAC, Menlo Park, California, USA

In 2019 SLAC is building a new linear accelerator based on superconducting niobium cavities. The first one, now called the copper linac, could generate 120 electron bunches per second. The new one, called superconducting linac, will generate 1 million per second, bringing some challenges to many devices along with the accelerator. Most of them receive sensors and actuators in a VME-based Platform with its control running in software, with RTEMS as OS. This is feasible for 120 Hz, but not for 1 MHz. The new control hardware is ATCA-based Platform, that has carrier boards with FPGA connected to servers running Embedded real-time Linux OS, forming the High-Performance System (HPS). Instead of having all the new architecture installed at the accelerator and tested on the go, SLAC used the strategy of testing the systems in the copper linac, to have them ready to use in the superconducting linac in what was called the Mission Readiness Program. The Bunch Length System and the Bunch Charge System are examples of devices of this program. Both systems were tested in the copper linac at 120 Hz, with excellent results. The next step is to test them at the superconducting linac, at 1 MHz.

Poster WEPHA044 [1.308 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2019-WEPHA044

About •

paper received ※ 28 September 2019 paper accepted ※ 09 October 2019 issue date ※ 30 August 2020

Export •

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

THCPR07

Electronics for LCLS-II Beam Containment System Loss Monitors

1641

R.A. Kadyrov, C.I. Clarke, A.S. Fisher, M. Petree, C. Yee
SLAC, Menlo Park, California, USA

LCLS-II is a new FEL which is under construction at SLAC National Accelerator Laboratory. Its superconducting electron linac is able to produce up to 1.2 MW of beam power. In event of electron beam loss, radiation levels can exceed allowed levels outside thin shielding originally built for a lower energy LCLS linac. Beam Containment System (BCS) loss monitors are employed to detect the radiation and shut-off the beam within 200 µs, limit the radiation dose in occupied areas and minimize damage to the equipment. sCVD single-crystal diamond particle detectors are used as Point Beam Loss Monitors (PBLM) to detect losses locally. Fiber optics is selected as Long Beam Loss Monitor (LBLM). PMT at downstream end of the LBLM detects light produced by Cherenkov radiation. LBLM provides continuous coverage along electron beam path from the gun to the dump. Unified set of electronics is designed to integrate the charge from PMT or sCVD, compare the loss with predefined threshold and generate the fault if the limit is breached. Continuous self-checking is implemented for both types of sensors. Challenges in electronics design, cable selection and self-checking implementation are discussed.

Slides THCPR07 [1.204 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2019-THCPR07

About •

paper received ※ 27 September 2019 paper accepted ※ 09 October 2019 issue date ※ 30 August 2020

Export •

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