ICALEPCS2021 - List of Authors (Kaji, H.)

Paper	Title	Page
THPV027	Application of the White Rabbit System at SuperKEKB	919
	H. Kaji KEK, Ibaraki, Japan Y. Iitsuka EJIT, Hitachi, Ibaraki, Japan
	We employ the White Rabbit system to satisfy the increasing requests from the SuperKEKB operations. The SuperKEKB-type slave node was developed based on the SPEC board and FMC-DIO card. The firmware was customized slightly to realize the SuperKEKB needs. The device/driver for EPICS was developed. The five slave nodes have been operated since the 2021 autumn run. The delivery of the beam permission signal from the central control building to the injector linac is taken care of by new slave nodes. The timing of the abort request signal and the trigger for the abort kicker magnet are recorded with the distributed TDC system. More slave nodes will be installed in the next year to enhance the role of the distributed TDC system.
	Poster THPV027 [1.186 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2021-THPV027
About •	Received ※ 10 October 2021 Revised ※ 25 October 2021 Accepted ※ 21 November 2021 Issue date ※ 08 January 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPV028	Analysis of AC Line Fluctuation for Timing System at KEK	923
	D. Wang Sokendai, Ibaraki, Japan Y. Enomoto, K. Furukawa, H. Kaji, F. Miyahara, M. Sato, H. Sugimura KEK, Ibaraki, Japan
	The timing system controls the injection procedure of the accelerator by performing signal synchronization and trigger delivery to the devices all over the installations at KEK. The trigger signals is usually generated at the same phase of an AC power line to reduce the unwanted variation of the beam quality. This requirement originates from the power supply systems. However, the AC line synchronization conflicts with the bucket selection process of SuperKEKB low energy ring (LER) which stores the positron beam. The positron beam is firstly injected into a damping ring (DR) to lower the emittance before entering desired RF bucket in LER. A long bucket selection cycle for DR and LER makes it difficult to coincide with AC line every injection pulse. This trouble is solved by grouping several injection pulses into various of injection sequences and manipulating the length of sequences to adjust the AC line arrival timing. Therefore, the timing system is sensitive to drastically AC line fluctuation. The failure of timing system caused by strong AC line fluctuation and solutions are introduced in this work.
	Poster THPV028 [1.010 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2021-THPV028
About •	Received ※ 17 October 2021 Revised ※ 28 October 2021 Accepted ※ 21 November 2021 Issue date ※ 09 December 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Application of the White Rabbit System at SuperKEKB

919

H. Kaji
KEK, Ibaraki, Japan
Y. Iitsuka
EJIT, Hitachi, Ibaraki, Japan

We employ the White Rabbit system to satisfy the increasing requests from the SuperKEKB operations. The SuperKEKB-type slave node was developed based on the SPEC board and FMC-DIO card. The firmware was customized slightly to realize the SuperKEKB needs. The device/driver for EPICS was developed. The five slave nodes have been operated since the 2021 autumn run. The delivery of the beam permission signal from the central control building to the injector linac is taken care of by new slave nodes. The timing of the abort request signal and the trigger for the abort kicker magnet are recorded with the distributed TDC system. More slave nodes will be installed in the next year to enhance the role of the distributed TDC system.

Poster THPV027 [1.186 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2021-THPV027

About •

Received ※ 10 October 2021 Revised ※ 25 October 2021 Accepted ※ 21 November 2021 Issue date ※ 08 January 2022

Cite •

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

THPV028

Analysis of AC Line Fluctuation for Timing System at KEK

923

D. Wang
Sokendai, Ibaraki, Japan
Y. Enomoto, K. Furukawa, H. Kaji, F. Miyahara, M. Sato, H. Sugimura
KEK, Ibaraki, Japan

The timing system controls the injection procedure of the accelerator by performing signal synchronization and trigger delivery to the devices all over the installations at KEK. The trigger signals is usually generated at the same phase of an AC power line to reduce the unwanted variation of the beam quality. This requirement originates from the power supply systems. However, the AC line synchronization conflicts with the bucket selection process of SuperKEKB low energy ring (LER) which stores the positron beam. The positron beam is firstly injected into a damping ring (DR) to lower the emittance before entering desired RF bucket in LER. A long bucket selection cycle for DR and LER makes it difficult to coincide with AC line every injection pulse. This trouble is solved by grouping several injection pulses into various of injection sequences and manipulating the length of sequences to adjust the AC line arrival timing. Therefore, the timing system is sensitive to drastically AC line fluctuation. The failure of timing system caused by strong AC line fluctuation and solutions are introduced in this work.

Poster THPV028 [1.010 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICALEPCS2021-THPV028

About •

Received ※ 17 October 2021 Revised ※ 28 October 2021 Accepted ※ 21 November 2021 Issue date ※ 09 December 2021

Cite •

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