IBIC2019 - List of Authors (Tobiyama, M.)

Paper	Title	Page
MOPP028	Longitudinal Bunch-by-Bunch Feedback Systems for SuperKEKB LER	159
	M. Tobiyama, J.W. Flanagan, T. Kobayashi, S. Terui KEK, Ibaraki, Japan J.D. Fox Stanford University, Stanford, California, USA
	Longitudinal bunch-by-bunch feedback systems to suppress coupled bunch instabilities with minimum bunch spacing of 2 ns have been constructed in SuperKEKB LER. Through the grow-damp and excite-damp experiments with several filling patterns and the transient-domain analysis of unstable modes, the behaviors of possible impedance sources have been evaluated. The measured performance of the system, together with the performance of the related systems such as slow phase feedback to the reference RF clock are reported.
	Poster MOPP028 [0.519 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP028
About •	paper received ※ 03 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPP018	Synchrotron Radiation Monitor for SuperKEKB Damping Ring in Phase-III Operation	336
	H. Ikeda, J.W. Flanagan, H. Fukuma, H. Sugimoto, M. Tobiyama KEK, Ibaraki, Japan
	The SuperKEKB damping ring (DR) commissioned in March 2019, before main ring (MR) Phase-III operation. The design luminosity of SuperKEKB is 40 times that of KEKB with high current and low emittance. We constructed the DR in order to deliver a low-emittance positron beam. A synchrotron radiation monitor (SRM) was installed for beam diagnostics at the DR. Streak camera and gated camera were used for measurement of the damping time and the beam size. This paper shows the design of DR SRM and the result of the measurement.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP018
About •	paper received ※ 04 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPP030	Betatron Phase Advance Measurements Using the Gated Turn-by-turn Monitors at SuperKEKB	591
	G. Mitsuka, K. Mori, M. Tobiyama KEK, Ibaraki, Japan
	In the SuperKEKB commissioning Phases 2 (Feb.-Jul., 2018) and 3 (from Mar. 2019), the betatron phase advances between adjacent beam position monitors have been measured using a total of 138 gated turn-by-turn monitors. A fast RF gating of the monitors enables turn-by-turn beam position detections by focusing only on an artificially-excited non-colliding bunch, while leaving colliding bunches unaffected. Betatron phase advances measured by the gated turn-by-turn monitors and accordingly obtained betatron functions were consistent with the closed orbit measurements. High signal-to-noise ratio were achieved by advanced signal extraction methods such as NAFF, SVD, and independent component analysis.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP030
About •	paper received ※ 03 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Longitudinal Bunch-by-Bunch Feedback Systems for SuperKEKB LER

159

M. Tobiyama, J.W. Flanagan, T. Kobayashi, S. Terui
KEK, Ibaraki, Japan
J.D. Fox
Stanford University, Stanford, California, USA

Longitudinal bunch-by-bunch feedback systems to suppress coupled bunch instabilities with minimum bunch spacing of 2 ns have been constructed in SuperKEKB LER. Through the grow-damp and excite-damp experiments with several filling patterns and the transient-domain analysis of unstable modes, the behaviors of possible impedance sources have been evaluated. The measured performance of the system, together with the performance of the related systems such as slow phase feedback to the reference RF clock are reported.

Poster MOPP028 [0.519 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP028

About •

paper received ※ 03 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019

Export •

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

TUPP018

Synchrotron Radiation Monitor for SuperKEKB Damping Ring in Phase-III Operation

336

H. Ikeda, J.W. Flanagan, H. Fukuma, H. Sugimoto, M. Tobiyama
KEK, Ibaraki, Japan

The SuperKEKB damping ring (DR) commissioned in March 2019, before main ring (MR) Phase-III operation. The design luminosity of SuperKEKB is 40 times that of KEKB with high current and low emittance. We constructed the DR in order to deliver a low-emittance positron beam. A synchrotron radiation monitor (SRM) was installed for beam diagnostics at the DR. Streak camera and gated camera were used for measurement of the damping time and the beam size. This paper shows the design of DR SRM and the result of the measurement.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP018

About •

paper received ※ 04 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019

Export •

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

WEPP030

Betatron Phase Advance Measurements Using the Gated Turn-by-turn Monitors at SuperKEKB

591

G. Mitsuka, K. Mori, M. Tobiyama
KEK, Ibaraki, Japan

In the SuperKEKB commissioning Phases 2 (Feb.-Jul., 2018) and 3 (from Mar. 2019), the betatron phase advances between adjacent beam position monitors have been measured using a total of 138 gated turn-by-turn monitors. A fast RF gating of the monitors enables turn-by-turn beam position detections by focusing only on an artificially-excited non-colliding bunch, while leaving colliding bunches unaffected. Betatron phase advances measured by the gated turn-by-turn monitors and accordingly obtained betatron functions were consistent with the closed orbit measurements. High signal-to-noise ratio were achieved by advanced signal extraction methods such as NAFF, SVD, and independent component analysis.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP030

About •

paper received ※ 03 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019

Export •

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