IPAC2014 - List of Authors (Baboi, N.)

Paper	Title	Page
WEPRI029	Simulations and Measurements of Beam Pipe Modes excited in 9-cell Superconducting Cavities	2540
	A. Kuramoto Sokendai, Ibaraki, Japan N. Baboi DESY, Hamburg, Germany H. Hayano KEK, Ibaraki, Japan
	Higher order modes (HOM) excited in 9-cell superconducting cavities have been studied to detect cavity alignment. Dipole modes have been monitored, since their magnitude is proportional to beam offsets from their electrical centers. Detection of cavity alignment is important for the ILC to confirm alignment accuracy and furthermore possible source of emittance growth. We are particularly interested in beam pipe modes because they are localized in both ends of the cavity. We measured beam-induced HOM in the STF accelerator at KEK in 2012 – 2013. From the results of the measurement, we found some modes whose behaviors are like dipole mode at around 2.1 GHz instead of 2.28 GHz as calculated by R. Wanzenberg for an ideal cavity [TESLA 2001-33, September 2001]. We also measured beam induced HOM in the TESLA superconducting cavities in FLASH at DESY. In order to identify beam pipe modes and to compare the measurement with the calculation, we calculate beam pipe modes of 9-cell superconducting cavity by CST MICROWAVE STUDIO 2012 and HFSS 12. We will discuss about these calculations and the measurement.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI029
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THPME117	First Tests with the Self-triggered Mode of the New MicroTCA-based Low-charge Electronics for Button and Stripline BPMs at FLASH	3509
	F. Schmidt-Föhre, N. Baboi, G. Kuehn, B. Lorbeer, D. Nölle, K. Wittenburg DESY, Hamburg, Germany
	The FLASH facility at DESY is currently enhanced by a second beamline (FLASH2) to extend the capacity for user experiments. In addition, certain support systems like the timing system and the BPM system at the existing FLASH accelerator have been partly renewed and are now under commissioning. New button BPM electronics based on the MTCA.4 for physics standard is provided for the FLASH2 beamline and is foreseen as a replacement of the old BPM electronics at FLASH. Compared to the predecessor of the FLASH button BPM electronics, the new system has been specifically designed for low charge operation exceeding a wide dynamical charge range between 100pC and 3nC. Special provisions have been made to enable single bunch measurements in a self-triggered mode, enabling timing-system-independent measurements during commissioning and at fallback during normal operation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME117
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Simulations and Measurements of Beam Pipe Modes excited in 9-cell Superconducting Cavities

2540

A. Kuramoto
Sokendai, Ibaraki, Japan
N. Baboi
DESY, Hamburg, Germany
H. Hayano
KEK, Ibaraki, Japan

Higher order modes (HOM) excited in 9-cell superconducting cavities have been studied to detect cavity alignment. Dipole modes have been monitored, since their magnitude is proportional to beam offsets from their electrical centers. Detection of cavity alignment is important for the ILC to confirm alignment accuracy and furthermore possible source of emittance growth. We are particularly interested in beam pipe modes because they are localized in both ends of the cavity. We measured beam-induced HOM in the STF accelerator at KEK in 2012 – 2013. From the results of the measurement, we found some modes whose behaviors are like dipole mode at around 2.1 GHz instead of 2.28 GHz as calculated by R. Wanzenberg for an ideal cavity [TESLA 2001-33, September 2001]. We also measured beam induced HOM in the TESLA superconducting cavities in FLASH at DESY. In order to identify beam pipe modes and to compare the measurement with the calculation, we calculate beam pipe modes of 9-cell superconducting cavity by CST MICROWAVE STUDIO 2012 and HFSS 12. We will discuss about these calculations and the measurement.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI029

Export •

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

THPME117

First Tests with the Self-triggered Mode of the New MicroTCA-based Low-charge Electronics for Button and Stripline BPMs at FLASH

3509

F. Schmidt-Föhre, N. Baboi, G. Kuehn, B. Lorbeer, D. Nölle, K. Wittenburg
DESY, Hamburg, Germany

The FLASH facility at DESY is currently enhanced by a second beamline (FLASH2) to extend the capacity for user experiments. In addition, certain support systems like the timing system and the BPM system at the existing FLASH accelerator have been partly renewed and are now under commissioning. New button BPM electronics based on the MTCA.4 for physics standard is provided for the FLASH2 beamline and is foreseen as a replacement of the old BPM electronics at FLASH. Compared to the predecessor of the FLASH button BPM electronics, the new system has been specifically designed for low charge operation exceeding a wide dynamical charge range between 100pC and 3nC. Special provisions have been made to enable single bunch measurements in a self-triggered mode, enabling timing-system-independent measurements during commissioning and at fallback during normal operation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME117

Export •

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