LINAC2022 - List of Authors (Bousonville, M.)

Paper	Title	Page
TUPOPA17	Solving the USB Communication Problem of the High-Voltage Modulator Control System in the European XFEL	451
	M. Bousonville, S. Choroba, T. Grevsmühl, S. Göller, A. Hauberg, T. Weinhausen DESY, Hamburg, Germany
	Since the commissioning of the modulators in the European XFEL in 2016, it happened from time to time that the modulator control system hung up. The reason for the problem was unknown at that time. Initially, the MTBF (Mean Time Between Failure) was 10⁴ days, which was so rare that other problems with the RF system clearly dominated and were addressed first. Over the next 2 years, the error became more frequent and occurred on average every 18 days. After the winter shutdown of the XFEL in 2020, the problem became absolutely dominant, with an MTBF of 2 days. Therefore, the fault was investigated with top priority and was finally identified. Two units of the control electronics communicate via USB 2.0 with the main server. Using special measurement technology, it was possible to prove that weak signal levels in the USB signal led to bit errors and thus to the crash of the control electronics. This article describes the troubleshooting process, how to measure the signal quality of USB signals and how the problem was solved in the end.
	Poster TUPOPA17 [6.650 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TUPOPA17
About •	Received ※ 22 August 2022 — Revised ※ 19 August 2022 — Accepted ※ 29 August 2022 — Issue date ※ 15 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOJO03	RF Performance of a Next-Generation L-Band RF Gun at PITZ	699
	M. Krasilnikov, Z. Aboulbanine, G.D. Adhikari, N. Aftab, P. Boonpornprasert, M.E. Castro Carballo, G.Z. Georgiev, J. Good, M. Groß, A. Hoffmann, C. Koschitzki, X.-K. Li, A. Lueangaramwong, D. Melkumyan, R. Niemczyk, A. Oppelt, B. Petrosyan, S. Philipp, M. Pohl, H.J. Qian, C.J. Richard, J. Schultze, F. Stephan, G. Vashchenko, T. Weilbach DESY Zeuthen, Zeuthen, Germany M. Bousonville, F. Brinker, M. Hoffmann, K. Knebel, D. Kostin, S. Lederer, L. Lilje, S. Pfeiffer, R. Ritter, S. Schreiber, H. Weise, J. Ziegler DESY, Hamburg, Germany G. Shu IHEP, Beijing, People’s Republic of China M. Wenskat University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
	A new generation of normal conducting 1.3GHz RF gun was developed to provide a high-quality electron source for superconducting linac driven free-electron lasers like FLASH and European XFEL. Compared to the Gun4 series, Gun5 aims for a 50% increase of the duration of the RF pulse (up to 1 ms at 10 Hz repetition rate) combined with high gradients (up to ~60 MV/m at the cathode). In addition to the improved impedance, the new cavity is equipped with an RF probe to measure and control the amplitude and phase of the RF field inside the gun. The first prototype of the new RF gun was manufactured at DESY and installed at the Photo Injector Test facility at DESY in Zeuthen (PITZ) in October 2021. In mid-October 2021 the RF conditioning began, aiming for achieving the aforementioned RF parameters. The conditioning procedure involves a slow gradual increase in repetition rate, RF pulse duration and peak power while carefully monitoring vacuum conditions and signals from interlock sensors. The results of RF conditioning will be reported.
	Poster THPOJO03 [2.241 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOJO03
About •	Received ※ 26 August 2022 — Revised ※ 31 August 2022 — Accepted ※ 03 September 2022 — Issue date ※ 15 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Solving the USB Communication Problem of the High-Voltage Modulator Control System in the European XFEL

451

M. Bousonville, S. Choroba, T. Grevsmühl, S. Göller, A. Hauberg, T. Weinhausen
DESY, Hamburg, Germany

Since the commissioning of the modulators in the European XFEL in 2016, it happened from time to time that the modulator control system hung up. The reason for the problem was unknown at that time. Initially, the MTBF (Mean Time Between Failure) was 10⁴ days, which was so rare that other problems with the RF system clearly dominated and were addressed first. Over the next 2 years, the error became more frequent and occurred on average every 18 days. After the winter shutdown of the XFEL in 2020, the problem became absolutely dominant, with an MTBF of 2 days. Therefore, the fault was investigated with top priority and was finally identified. Two units of the control electronics communicate via USB 2.0 with the main server. Using special measurement technology, it was possible to prove that weak signal levels in the USB signal led to bit errors and thus to the crash of the control electronics. This article describes the troubleshooting process, how to measure the signal quality of USB signals and how the problem was solved in the end.

Poster TUPOPA17 [6.650 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TUPOPA17

About •

Received ※ 22 August 2022 — Revised ※ 19 August 2022 — Accepted ※ 29 August 2022 — Issue date ※ 15 September 2022

Cite •

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

THPOJO03

RF Performance of a Next-Generation L-Band RF Gun at PITZ

699

M. Krasilnikov, Z. Aboulbanine, G.D. Adhikari, N. Aftab, P. Boonpornprasert, M.E. Castro Carballo, G.Z. Georgiev, J. Good, M. Groß, A. Hoffmann, C. Koschitzki, X.-K. Li, A. Lueangaramwong, D. Melkumyan, R. Niemczyk, A. Oppelt, B. Petrosyan, S. Philipp, M. Pohl, H.J. Qian, C.J. Richard, J. Schultze, F. Stephan, G. Vashchenko, T. Weilbach
DESY Zeuthen, Zeuthen, Germany
M. Bousonville, F. Brinker, M. Hoffmann, K. Knebel, D. Kostin, S. Lederer, L. Lilje, S. Pfeiffer, R. Ritter, S. Schreiber, H. Weise, J. Ziegler
DESY, Hamburg, Germany
G. Shu
IHEP, Beijing, People’s Republic of China
M. Wenskat
University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany

A new generation of normal conducting 1.3GHz RF gun was developed to provide a high-quality electron source for superconducting linac driven free-electron lasers like FLASH and European XFEL. Compared to the Gun4 series, Gun5 aims for a 50% increase of the duration of the RF pulse (up to 1 ms at 10 Hz repetition rate) combined with high gradients (up to ~60 MV/m at the cathode). In addition to the improved impedance, the new cavity is equipped with an RF probe to measure and control the amplitude and phase of the RF field inside the gun. The first prototype of the new RF gun was manufactured at DESY and installed at the Photo Injector Test facility at DESY in Zeuthen (PITZ) in October 2021. In mid-October 2021 the RF conditioning began, aiming for achieving the aforementioned RF parameters. The conditioning procedure involves a slow gradual increase in repetition rate, RF pulse duration and peak power while carefully monitoring vacuum conditions and signals from interlock sensors. The results of RF conditioning will be reported.

Poster THPOJO03 [2.241 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOJO03

About •

Received ※ 26 August 2022 — Revised ※ 31 August 2022 — Accepted ※ 03 September 2022 — Issue date ※ 15 September 2022

Cite •

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