IBIC2023 - List of Authors (Sapozhnikov, L.)

Paper	Title	Page
TU3I01	Commissioning of the LCLS-II Machine Protection System for MHz CW Beams	154
	J.A. Mock, A.S. Fisher, R.T. Herbst, P. Krejcik, L. Sapozhnikov SLAC, Menlo Park, California, USA
	Beam power at the LCLS-II linac and FEL can be as high as several hundered kW with CW beam rates up to 1 MHz. The new MPS has a latency of less than 100 µs to prevent damage when a fault or beam loss is detected. The MPS architecture encompasses the multiple FEL beamlines served by the SC linac and can mitigate a fault in one beamline without impacting the beam rate in a neighboring beamline. The MPS receives inputs from various devices including loss monitors and charge monitors as well as magnet power supplies and BPMs to pre-emptively turn of the beam if a fault condition is detected. Link nodes distributed around the facility gather the input data and stream it back to a central processor that signals other link nodes connected to beam rate control devices. Commmissioning and experience with the new system will be described.
	Slides TU3I01 [4.239 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TU3I01
About •	Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 12 September 2023 — Issue date ※ 25 September 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP005	Commissioning the Beam-Loss Monitoring System of the LCLS Superconducting Linac	187
	A.S. Fisher, N. Balakrishnan, G.W. Brown, E.P. Chin, W.G. Cobau, J.E. Dusatko, B.T. Jacobson, S. Kwon, J.A. Mock, J. Park, J. Pigula, E. Rodriguez, J.I.D. Rudolph, D. Sanchez, L. Sapozhnikov, J.J. Welch SLAC, Menlo Park, California, USA
	A 4-GeV superconducting linac has been added to the LCLS x-ray FEL facility at SLAC. Its 120-kW, 1-MHz beam requires new beam-loss monitors (BLMs) for radiation protection, machine protection, and diagnostics. Long radiation-hard optical fibres span the full 4 km from the electron gun of the SC linac to the final beam dump. Diamond detectors at anticipated loss points provide local protection. Detector signals are continuously integrated with a 500-ms time constant and compared to a loss threshold. If crossed, the beam is halted within 0.1 ms. Commissioning began in March 2022 with the 100-MeV injector and with RF processing of the cryomodules. At IBIC 2022 last September, we presented commissioning results from the injector BLMs. In October, the beam passed through the full linac and the bypass transport line above the LCLS copper linac, stopping at an intermediate dump. In August it continued through the soft x-ray undulator and achieved first lasing. Here we present BLM commissioning at energies up to 4 GeV and rates up to 100 kHz. We discuss measurements and software using the fast diagnostic-waveform output to localize beam losses and to detect wire-scanner signals.
	Poster TUP005 [2.620 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TUP005
About •	Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 13 September 2023 — Issue date ※ 27 September 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Commissioning of the LCLS-II Machine Protection System for MHz CW Beams

154

J.A. Mock, A.S. Fisher, R.T. Herbst, P. Krejcik, L. Sapozhnikov
SLAC, Menlo Park, California, USA

Beam power at the LCLS-II linac and FEL can be as high as several hundered kW with CW beam rates up to 1 MHz. The new MPS has a latency of less than 100 µs to prevent damage when a fault or beam loss is detected. The MPS architecture encompasses the multiple FEL beamlines served by the SC linac and can mitigate a fault in one beamline without impacting the beam rate in a neighboring beamline. The MPS receives inputs from various devices including loss monitors and charge monitors as well as magnet power supplies and BPMs to pre-emptively turn of the beam if a fault condition is detected. Link nodes distributed around the facility gather the input data and stream it back to a central processor that signals other link nodes connected to beam rate control devices. Commmissioning and experience with the new system will be described.

Slides TU3I01 [4.239 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TU3I01

About •

Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 12 September 2023 — Issue date ※ 25 September 2023

Cite •

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

TUP005

Commissioning the Beam-Loss Monitoring System of the LCLS Superconducting Linac

187

A.S. Fisher, N. Balakrishnan, G.W. Brown, E.P. Chin, W.G. Cobau, J.E. Dusatko, B.T. Jacobson, S. Kwon, J.A. Mock, J. Park, J. Pigula, E. Rodriguez, J.I.D. Rudolph, D. Sanchez, L. Sapozhnikov, J.J. Welch
SLAC, Menlo Park, California, USA

A 4-GeV superconducting linac has been added to the LCLS x-ray FEL facility at SLAC. Its 120-kW, 1-MHz beam requires new beam-loss monitors (BLMs) for radiation protection, machine protection, and diagnostics. Long radiation-hard optical fibres span the full 4 km from the electron gun of the SC linac to the final beam dump. Diamond detectors at anticipated loss points provide local protection. Detector signals are continuously integrated with a 500-ms time constant and compared to a loss threshold. If crossed, the beam is halted within 0.1 ms. Commissioning began in March 2022 with the 100-MeV injector and with RF processing of the cryomodules. At IBIC 2022 last September, we presented commissioning results from the injector BLMs. In October, the beam passed through the full linac and the bypass transport line above the LCLS copper linac, stopping at an intermediate dump. In August it continued through the soft x-ray undulator and achieved first lasing. Here we present BLM commissioning at energies up to 4 GeV and rates up to 100 kHz. We discuss measurements and software using the fast diagnostic-waveform output to localize beam losses and to detect wire-scanner signals.

Poster TUP005 [2.620 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TUP005

About •

Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 13 September 2023 — Issue date ※ 27 September 2023

Cite •

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