FLS2018 - List of Keywords (operation)

Paper	Title	Other Keywords	Page
WEP2PT024	Influences of Harmonic Cavities on the Single-Bunch Instabilities in Electron Storage Rings	ion, cavity, impedance, storage-ring	128
	H.S. Xu, N. Wang IHEP, Beijing, People's Republic of China
	Single-bunch instabilities usually determine the bunch performance at high charges as well as the highest single- bunch currents in storage rings. It has been demonstrated that the passive harmonic cavities, which have been widely used in electron storage rings of the third-generation synchrotron light sources, can generally make the beam more stable. However, the influences of the harmonic cavities on the single-bunch instabilities are still not fully understood. We hereby present our study of both longitudinal and transverse single-bunch instabilities when using different settings of the harmonic cavities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT024
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PT033	Conceptual Design of Superconducting Transverse Gradient Undulator for PAL-XFEL Beamline	ion, FEL, undulator, electron	142
	S.J. Lee, J.H. Han PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT \& Future Planning(2017R1C1B1012852) Recently, the transverse gradient undulator (TGU) applications are suggested from the laser plasma wake-field accelerator (LPWA) to ultimate storage ring (USR). Especially for X-ray FEL, TGU can be used to generate the large bandwidth radiation (up to §I10{\percent}). In this proceeding, the review of PAL-XFEL beam parameters and TGU requirements was done to apply a variable large bandwidth operation to the PAL-XFEL beamlines. Also, the conceptual design of TGU, based on superconducting undulator (SCU) was proposed, and B-field calculation results were introduced for PAL-XFEL large bandwidth operation mode.
	Poster WEP2PT033 [0.927 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT033
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP2WB03	Transparent Lattice Characterization with Gated Turn-by-Turn Data of Diagnostic Bunch-Train	ion, lattice, wakefield, storage-ring	171
	Y. Li, W.X. Cheng, K. Ha, R.S. Rainer BNL, Upton, Long Island, New York, USA
	Funding: This work was supported by Depart- ment of Energy Contract No. DE-SC0012704. Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate Diagnostic Bunch-Train (DBT). Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT, from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. This approach allows us to localize the distributed quadrupolar wake fields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta-beat and phase-beat, and unobtrusively optimize performance of National Synchrotron Light Source-II accelerator during routine operations.
	Slides THP2WB03 [0.711 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THP2WB03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

WEP2PT024

Influences of Harmonic Cavities on the Single-Bunch Instabilities in Electron Storage Rings

ion, cavity, impedance, storage-ring

128

H.S. Xu, N. Wang
IHEP, Beijing, People's Republic of China

Single-bunch instabilities usually determine the bunch performance at high charges as well as the highest single- bunch currents in storage rings. It has been demonstrated that the passive harmonic cavities, which have been widely used in electron storage rings of the third-generation synchrotron light sources, can generally make the beam more stable. However, the influences of the harmonic cavities on the single-bunch instabilities are still not fully understood. We hereby present our study of both longitudinal and transverse single-bunch instabilities when using different settings of the harmonic cavities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT024

Export •

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

WEP2PT033

Conceptual Design of Superconducting Transverse Gradient Undulator for PAL-XFEL Beamline

ion, FEL, undulator, electron

142

S.J. Lee, J.H. Han
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT \& Future Planning(2017R1C1B1012852)
Recently, the transverse gradient undulator (TGU) applications are suggested from the laser plasma wake-field accelerator (LPWA) to ultimate storage ring (USR). Especially for X-ray FEL, TGU can be used to generate the large bandwidth radiation (up to §I10{\percent}). In this proceeding, the review of PAL-XFEL beam parameters and TGU requirements was done to apply a variable large bandwidth operation to the PAL-XFEL beamlines. Also, the conceptual design of TGU, based on superconducting undulator (SCU) was proposed, and B-field calculation results were introduced for PAL-XFEL large bandwidth operation mode.

Poster WEP2PT033 [0.927 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT033

Export •

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

THP2WB03

Transparent Lattice Characterization with Gated Turn-by-Turn Data of Diagnostic Bunch-Train

ion, lattice, wakefield, storage-ring

171

Y. Li, W.X. Cheng, K. Ha, R.S. Rainer
BNL, Upton, Long Island, New York, USA

Funding: This work was supported by Depart- ment of Energy Contract No. DE-SC0012704.
Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate Diagnostic Bunch-Train (DBT). Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT, from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. This approach allows us to localize the distributed quadrupolar wake fields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta-beat and phase-beat, and unobtrusively optimize performance of National Synchrotron Light Source-II accelerator during routine operations.

Slides THP2WB03 [0.711 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THP2WB03

Export •

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