FLS2023 - List of Keywords (storage-ring)

Paper	Title	Other Keywords	Page
MO2L2	Storage Ring Based Steady State Microbunching	radiation, laser, electron, bunching	1
	A. Chao TUB, Beijing, People’s Republic of China
	Powerful light sources are highly desired tools for scientific research and for industrial applications. Electrons are the objects that most readily and easily radiate photons. A natural conclusion follows that one should pursue electron accelerators as the choice tools towards powerful light sources. How to manipulate the electron beam in the accelerator so that it radiates light most efficiently, however, remains to be studied and its physical principle and technical limits be explored and optimized for the purpose. One such proposed concepts is based on the steady state microbunching (SSMB) mechanism in an electron storage ring. We make a brief introduction of the SSMB mechanism and its recent status in this presentation.
	Slides MO2L2 [1.156 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO2L2
About •	Received ※ 25 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MO2L3	Review of Harmonic Cavities in Fourth-generation Storage Rings	cavity, synchrotron, electron, survey	8
	F.J. Cullinan, Å. Andersson, P. Tavares MAX IV Laboratory, Lund University, Lund, Sweden
	Several third generation light-source storage rings have used harmonic cavities to lengthen the electron bunches. With the advent of the fourth generation however, they have become an almost universal feature as the small transverse electron beam sizes make long bunches essential for increasing Touschek lifetime and reducing emittance blow-up from intrabeam scattering. Multiple technological solutions exist for the implementation of harmonic cavities and which to use remains an open question for many facilities. This is therefore a very active area of study in which there is strong collaboration within the community. Avoiding coherent collective beam instabilities is of particular concern. In this talk, I will summarise the results obtained so far. I will also give an overview of the observations made at the MAX IV 3 GeV ring, the first fourth generation storage ring which was commissioned with normal-conducting passive harmonic cavities already installed. Finally, I will discuss potential future directions.
	Slides MO2L3 [3.035 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO2L3
About •	Received ※ 24 August 2023 — Revised ※ 25 August 2023 — Accepted ※ 27 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MO3B4	Generating High Repetition Rate X-ray Attosecond Pulses in SAPS	radiation, laser, electron, dipole	22
	W. Liu, X. Liu, Y. Zhao IHEP CSNS, Guangdong Province, People’s Republic of China Y. Jiao, X. Li, S. Wang IHEP, Beijing, People’s Republic of China
	Attosecond, which refers to 10^-18 seconds, is the timescale of electron motion within an atom. Accurate observation of electron motion helps deepen the understanding of microscopic quantum processes such as charge transfer in molecules, wave packet dynamics, and charge transfer in organic photovoltaic materials. To meet the needs of relevant research, the South Advanced Photon Source (SAPS), currently in the design phase, is considering the construction of an attosecond beamline. This paper presents relevant research on achieving high-repetition-rate coherent attosecond pulses on the fourth-generation storage ring at SAPS. Realizing attosecond pulses in a storage ring requires femtosecond to sub-femtosecond-level longitudinal modulation of the beam, and the modulation scheme needs to consider multiple factors to avoid a significant impact on other users. The study shows that with high-power, few-cycle lasers, and advanced beam modulation techniques, the photon flux of attosecond pulses can be significantly enhanced with a minimal impact on the brightness of synchrotron radiation. Adopting high-repetition-rate lasers and precise time delay control, the repetition rate of attosecond pulses at SAPS can reach the megahertz level. Currently, the design wavelength range for attosecond pulses covers the water window (2.3-4.4 nm), which is "transparent" to water but strongly absorbed by elements constituting living organisms. This wavelength range has significant application value in fields such as biology and chemistry.
	Slides MO3B4 [3.400 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO3B4
About •	Received ※ 23 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MO4B3	Development of a Pulsed Injection Stripline for Diamond-II	injection, simulation, impedance, kicker	38
	R.T. Fielder, A. Lueangaramwong, A.F.D. Morgan DLS, Oxfordshire, United Kingdom
	Diamond-II will use a single bunch aperture sharing injection scheme. This applies a strong kick to both the injected and the targeted stored bunch with a very short duration (ideally <3 ns, if disturbance to the adjacent bunches is to be avoided). We have developed a design for the stripline kickers that can meet these requirements while minimising internal reflections and beam impedance. We show an analysis of the electric and magnetic fields produced by the stripline and simulations of the effects on injected and stored beam, and analysis of the wakefields and impedance of the structure.
	Slides MO4B3 [2.164 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO4B3
About •	Received ※ 21 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TU1B3	Nonlinear Optics From Hybrid Dispersive Orbits	sextupole, optics, quadrupole, lattice	62
	Y. Li, R.S. Rainer, V.V. Smaluk, D. Xu BNL, Upton, New York, USA
	Funding: Supported by US DoE under Contract No. DE-SC0012704 In this paper we present an expansion of the technique of characterizing nonlinear optics from off-energy orbits (NOECO) to cover harmonic sextupoles in storage rings. The existing NOECO technique has been successfully used to correct the chromatic sextupole errors on the MAX-IV machine, however, it did not account for harmonic sextupoles, which are widely used on many other machines. Through generating vertical dispersion with chromatic skew quadrupoles, a measurable dependence of nonlinear optics on harmonic sextupoles can be observed from hybrid horizontal and vertical dispersive orbits. Proof of concept of our expanded technique was accomplished by simulations and beam measurements on the National Synchrotron Light Source II (NSLS-II) storage ring.
	Slides TU1B3 [1.428 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU1B3
About •	Received ※ 18 August 2023 — Revised ※ 20 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TU4P18	Nonlinear Dynamics Measurements at the EBS Storage Ring	octupole, simulation, kicker, injection	116
	N. Carmignani, L.R. Carver, L. Hoummi, S.M. Liuzzo, T.P. Perron, S.M. White ESRF, Grenoble, France
	The EBS is a 4th generation synchrotron light source and it has been in user operation since August 2020 at the ESRF. Several measurements to characterise the nonlinear dynamics have been performed in 2023: nonlinear chromaticity, second order dispersion and detuning with amplitude. The results of the measurements are shown and compared with simulations.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P18
About •	Received ※ 23 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TU4P27	Progress of the HEPS Accelerator Construction and Linac Commissioning	linac, booster, MMI, photon	131
	C. Meng, J.S. Cao, Z. Duan, D.Y. He, P. He, H.F. Ji, Y. Jiao, W. Kang, J. Li, J.Y. Li, W.M. Pan, Y.M. Peng, H. Qu, S.K. Tian, G. Xu, H.S. Xu, J. Zhang, J.R. Zhang IHEP, Beijing, People’s Republic of China X.H. Lu IHEP CSNS, Guangdong Province, People’s Republic of China
	The High Energy Photon Source (HEPS) is the first fourth-generation synchrotron radiation source in China that has been on the track for construction. The accelerator complex of the light source is composed of a 7BA storage ring, a booster injector, a Linac pre-injector, and three transfer lines. In order to provide high-bunch-charge beams for the storage ring, the booster was designed to be capable of both beam acceleration from low injection energy to extraction energy and charge accumulation at the extraction energy by means of accepting electron bunches from the storage ring. The Linac was built using S-band normal conducting structures, and can provide electron beam with pulse charge up to 7 nC. This paper reports the progress of the construction of the accelerators, including the installation of the storage ring, the pre-commissioning tests of the booster, and commissioning of the Linac. In particular, the beam commissioning of the Linac will be introduced in detail.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P27
About •	Received ※ 29 August 2023 — Revised ※ 29 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TU4P28	Useful Formulas and Example Parameters Set for the Design of SSMB Storage Rings	radiation, laser, bunching, undulator	135
	X.J. Deng, A. Chao, W.-H. Huang, Z.Z. Li, Z. Pan, C.-X. Tang TUB, Beijing, People’s Republic of China
	A promising accelerator light source mechanism called steady-state microbunching (SSMB) has been actively studied in recent years. Here we summarize some important formulas for the design of SSMB storage rings. Generally we group our formulas into two categories, i.e., a longitudinal weak focusing storage ring for a desired radiation wavelength larger than 100 nm, and a transverse-longitudinal coupling, or a generalized longitudinal strong focusing, storage ring for a desired radiation wavelength between 1 nm and 100 nm. In each category, we have presented an example parameters set for the corresponding SSMB storage ring, to generate kW-level infrared, EUV and soft X-ray radiation, respectively.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P28
About •	Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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TU4P30	Optical Stochastic Cooling in a General Coupled Lattice	damping, undulator, pick-up, radiation	143
	X.J. Deng TUB, Beijing, People’s Republic of China
	Here we present a formalism of optical stochastic cooling in a 3D general coupled lattice. The formalism is general, and can treat a variety of damping and diffusion mechanisms within a single framework. We expect the work to be of value for the development of future light source.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P30
About •	Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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TU4P31	A Recursive Model for Laser-Electron-Radiation Interaction in Insertion Section of SSMB Storage Ring Based on Transverse-Longitudinal Coupling Scheme	laser, radiation, FEL, bunching	147
	C.-Y. Tsai HUST, Wuhan, People’s Republic of China X.J. Deng TUB, Beijing, People’s Republic of China
	Funding: This work is supported by the Fundamental Research Funds for the Central Universities (HUST) under Project No. 2021GCRC006 and National Natural Science Foundation of China under project No. 12275094. Recently a mechanism of the steady-state microbunching (SSMB) in a storage ring has been proposed and investigated. The SSMB aims to maintain the same excellent high repetition rate, close to continuous-wave operation, as the storage ring. Moreover, replacing the conventional RF cavity with a laser modulator for longitudinal focusing, the individual electron bunches can be microbunched in a steady state. The microbunched electron bunch train, with individual bunch length comparable to or shorter than the radiation wavelength, can not only produce coherent powerful synchrotron radiations but may also be subject to FEL-like collective instabilities. Our previous analysis was based on the wake-impedance model. In this paper, we have developed a recursive model for the laser modulator in the SSMB storage ring. In particular, the transverse-longitudinal coupling scheme is assumed. Equipped with the above matrix formalism, we can construct a recursive model to account for turn-by-turn evolution, including single-particle and second moments. It is possible to obtain a simplified analytical expression to identify the stability regime or tolerance range for non-perfect cancellation. C.-Y. Tsai, PRAB 25, 064401 (2022). C.-Y. Tsai, NIMA 1042 (2022) 167454. **X.J. Deng et al., NIMA 1019 (2021) 165859.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P31
About •	Received ※ 23 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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TU4P34	Recent Developments of the cSTART Project	injection, electron, lattice, cavity	155
	M. Schwarz, A. Bernhard, E. Bründermann, D. El Khechen, B. Härer, A. Malygin, A.-S. Müller, M.J. Nasse, G. Niehues, A.I. Papash, R. Ruprecht, J. Schäfer, M. Schuh, N.J. Smale, P. Wesolowski, C. Widmann KIT, Karlsruhe, Germany
	The combination of a compact storage ring and a laser-plasma accelerator (LPA) can serve as the basis for future compact light sources. One challenge is the large momentum spread (~ 2%) of the electron beams delivered by the LPA. To overcome this challenge, a very large acceptance compact storage ring (VLA-cSR) was designed as part of the compact STorage ring for Accelerator Research and Technology (cSTART) project. The project will be realized at the Karlsruhe Institute of Technology (KIT, Germany). Initially, the Ferninfrarot Linac- Und Test-Experiment (FLUTE), a source of ultra-short bunches, will serve as an injector for the VLA-cSR to benchmark and emulate LPA-like beams. In a second stage, a laser-plasma accelerator will be used as an injector, which is being developed as part of the ATHENA project in collaboration with DESY and the Helmholtz Institute Jena (HIJ). The small facility footprint, the large-momentum spread bunches with charges from 1 pC to 1 nC and lengths from few fs to few ps pose challenges for the lattice design, RF system and beam diagnostics. This contribution summarizes the latest results on these challenges.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P34
About •	Received ※ 21 August 2023 — Revised ※ 22 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
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WE4P18	Preliminary Design of Higher-order Achromat Lattice for the Upgrade of the Taiwan Photon Source	lattice, emittance, dipole, radiation	184
	N.Y. Huang, M.-S. Chiu, P.J. Chou, G.-H. Luo, H.W. Luo, H.-J. Tsai, F.H. Tseng NSRRC, Hsinchu, Taiwan
	We study the upgrade of Taiwan Photon Source (TPS) with energy saving as the prime objective. The upgrade design is dubbed TPS-II. To accommodate the constraints imposed by the existing TPS tunnel, we choose the higher-order achromat (HOA) lattice configuration which is composed of the 5BA and 4BA cells. This HOA lattice produces a natural beam emittance about 131 pm-rad for a 3 GeV, 518.4 m storage ring. The on-momentum dynamic aperture is about 8 mm and the estimated Touschek life time reaches around 5.7 hours at total beam current of 500 mA. As a result of the ultralow beam emittance, the brightness and coherence fraction (CF) of the photon beam are improved with a factor of several tens especially in the photon wavelength around 0.1 nm. The challenges and preliminary results of this HOA lattice design will be presented.
	Poster WE4P18 [5.398 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P18
About •	Received ※ 21 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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WE4P19	Simulation Study of Orbit Correction by Neural Network in Taiwan Photon Source	network, lattice, synchrotron, photon	188
	M.-S. Chiu, Y.-S. Cheng, G.-H. Luo, H.-J. Tsai, F.H. Tseng NSRRC, Hsinchu, Taiwan C.P. Felix MCL/ITRI, Hsinchu, Taiwan
	Machine learning has been applied in many fields in re-cent decades. Many research articles also presented re-markable achievements in either operation or designing of the particle accelerator. This paper focuses on the simulated orbit correction by neural networks, a subset of machine learning, in Taiwan Photon Source. The training data for the neural network is generated by accelerator toolbox (AT).
	Poster WE4P19 [0.843 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P19
About •	Received ※ 23 August 2023 — Revised ※ 29 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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WE4P21	Some Beam Dynamic Issues in the HALF Storage Ring	collimation, injection, scattering, operation	196
	J.Y. Tang USTC, SNST, Anhui, People’s Republic of China Z.H. Bai, T.L. He, G. Liu, Y. Mo, A.X. Wang, P.H. Yang, Z. Zhao USTC/NSRL, Hefei, Anhui, People’s Republic of China
	HALF (Hefei Advanced Light Facility) is a fourth-generation synchrotron light source that just started construction in 2023. With 2.2 GeV in energy, 350 mA in beam current and 86 pm.rad in emittance, the HALF storage ring faces several beam dynamics challenges. This presentation gives the recent study on some of these issues, in particular the beam collimation and the influence and compensation of the insertion devices. For beam collimation, different beam loss mechanisms have been studied, and the Touschek scattering and beam dumping are considered the two major effects in designing the collimation system. Then two collimators with movable horizontal blades and fixed passive vertical blades are being designed, with the main focus on the collimation efficiency and impedance. For the influence of the insertion devices, it is found that some of the long-period undulators have a high impact on the beam dynamic aperture due to low beam energy and originally small dynamic aperture. The local compensation methods for both linear and non-linear effects have been studied. Instead of the traditional compensation method by electrical wires, the method of using two combined magnets with quadrupole and octupole fields at the two ID ends in restoring the dynamic aperture is also studied and compared.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P21
About •	Received ※ 23 August 2023 — Revised ※ 30 August 2023 — Accepted ※ 01 September 2023 — Issued ※ 02 December 2023
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TH1D4	Bi-periodic Undulator: Innovative Insertion Device for SOLEIL II	undulator, synchrotron, electron, radiation	228
	A. Potet, F. Blache, P. Brunelle, M.-E. Couprie, O. Marcouillé, A. Mary, T. Mutin, A. Nadji, K. Tavakoli, C. de Oliveira SOLEIL, Gif-sur-Yvette, France
	SOLEIL II project will lead to optimize the production of photons by a modification of the present facility. The storage ring will be redesigned to reduce electron beam emittance, increase photon beam flux and brightness, and improve beamline resolution. The number of magnetic elements will be increased and the space reserved for insertion devices will be decreased by 30%. SOLEIL magnetic group searches for solutions to generate different magnetic periods in a smaller space to maintain the full spectral domain. Bi-Periodic undulator is an innovative and compact device allowing the use of two selectable magnetic periodicities by superimposition of magnets. The magnetic period can be switched from one value to its triple value by mechanical shift of magnetic arrays. A magnetic design has been performed and the construction of a prototype, including magnetic measurements and corrections, is under progress. The prototype will be installed in the storage ring with the goal to verify the feasibility of the model and to characterize the system. The magnetic fields, the radiation produced and the electron beam dynamics will be considered to have a complete knowledge on this undulator.
	Slides TH1D4 [2.442 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TH1D4
About •	Received ※ 23 August 2023 — Revised ※ 26 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MO2L2

Storage Ring Based Steady State Microbunching

radiation, laser, electron, bunching

1

A. Chao
TUB, Beijing, People’s Republic of China

Powerful light sources are highly desired tools for scientific research and for industrial applications. Electrons are the objects that most readily and easily radiate photons. A natural conclusion follows that one should pursue electron accelerators as the choice tools towards powerful light sources. How to manipulate the electron beam in the accelerator so that it radiates light most efficiently, however, remains to be studied and its physical principle and technical limits be explored and optimized for the purpose. One such proposed concepts is based on the steady state microbunching (SSMB) mechanism in an electron storage ring. We make a brief introduction of the SSMB mechanism and its recent status in this presentation.

Slides MO2L2 [1.156 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO2L2

About •

Received ※ 25 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

Cite •

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

MO2L3

Review of Harmonic Cavities in Fourth-generation Storage Rings

cavity, synchrotron, electron, survey

8

F.J. Cullinan, Å. Andersson, P. Tavares
MAX IV Laboratory, Lund University, Lund, Sweden

Several third generation light-source storage rings have used harmonic cavities to lengthen the electron bunches. With the advent of the fourth generation however, they have become an almost universal feature as the small transverse electron beam sizes make long bunches essential for increasing Touschek lifetime and reducing emittance blow-up from intrabeam scattering. Multiple technological solutions exist for the implementation of harmonic cavities and which to use remains an open question for many facilities. This is therefore a very active area of study in which there is strong collaboration within the community. Avoiding coherent collective beam instabilities is of particular concern. In this talk, I will summarise the results obtained so far. I will also give an overview of the observations made at the MAX IV 3 GeV ring, the first fourth generation storage ring which was commissioned with normal-conducting passive harmonic cavities already installed. Finally, I will discuss potential future directions.

Slides MO2L3 [3.035 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO2L3

About •

Received ※ 24 August 2023 — Revised ※ 25 August 2023 — Accepted ※ 27 August 2023 — Issued ※ 02 December 2023

Cite •

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

MO3B4

Generating High Repetition Rate X-ray Attosecond Pulses in SAPS

radiation, laser, electron, dipole

22

W. Liu, X. Liu, Y. Zhao
IHEP CSNS, Guangdong Province, People’s Republic of China
Y. Jiao, X. Li, S. Wang
IHEP, Beijing, People’s Republic of China

Attosecond, which refers to 10^-18 seconds, is the timescale of electron motion within an atom. Accurate observation of electron motion helps deepen the understanding of microscopic quantum processes such as charge transfer in molecules, wave packet dynamics, and charge transfer in organic photovoltaic materials. To meet the needs of relevant research, the South Advanced Photon Source (SAPS), currently in the design phase, is considering the construction of an attosecond beamline. This paper presents relevant research on achieving high-repetition-rate coherent attosecond pulses on the fourth-generation storage ring at SAPS. Realizing attosecond pulses in a storage ring requires femtosecond to sub-femtosecond-level longitudinal modulation of the beam, and the modulation scheme needs to consider multiple factors to avoid a significant impact on other users. The study shows that with high-power, few-cycle lasers, and advanced beam modulation techniques, the photon flux of attosecond pulses can be significantly enhanced with a minimal impact on the brightness of synchrotron radiation. Adopting high-repetition-rate lasers and precise time delay control, the repetition rate of attosecond pulses at SAPS can reach the megahertz level. Currently, the design wavelength range for attosecond pulses covers the water window (2.3-4.4 nm), which is "transparent" to water but strongly absorbed by elements constituting living organisms. This wavelength range has significant application value in fields such as biology and chemistry.

Slides MO3B4 [3.400 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO3B4

About •

Received ※ 23 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

Cite •

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

MO4B3

Development of a Pulsed Injection Stripline for Diamond-II

injection, simulation, impedance, kicker

38

R.T. Fielder, A. Lueangaramwong, A.F.D. Morgan
DLS, Oxfordshire, United Kingdom

Diamond-II will use a single bunch aperture sharing injection scheme. This applies a strong kick to both the injected and the targeted stored bunch with a very short duration (ideally <3 ns, if disturbance to the adjacent bunches is to be avoided). We have developed a design for the stripline kickers that can meet these requirements while minimising internal reflections and beam impedance. We show an analysis of the electric and magnetic fields produced by the stripline and simulations of the effects on injected and stored beam, and analysis of the wakefields and impedance of the structure.

Slides MO4B3 [2.164 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-MO4B3

About •

Received ※ 21 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

Cite •

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

TU1B3

Nonlinear Optics From Hybrid Dispersive Orbits

sextupole, optics, quadrupole, lattice

62

Y. Li, R.S. Rainer, V.V. Smaluk, D. Xu
BNL, Upton, New York, USA

Funding: Supported by US DoE under Contract No. DE-SC0012704
In this paper we present an expansion of the technique of characterizing nonlinear optics from off-energy orbits (NOECO) to cover harmonic sextupoles in storage rings. The existing NOECO technique has been successfully used to correct the chromatic sextupole errors on the MAX-IV machine, however, it did not account for harmonic sextupoles, which are widely used on many other machines. Through generating vertical dispersion with chromatic skew quadrupoles, a measurable dependence of nonlinear optics on harmonic sextupoles can be observed from hybrid horizontal and vertical dispersive orbits. Proof of concept of our expanded technique was accomplished by simulations and beam measurements on the National Synchrotron Light Source II (NSLS-II) storage ring.

Slides TU1B3 [1.428 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU1B3

About •

Received ※ 18 August 2023 — Revised ※ 20 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

Cite •

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

TU4P18

Nonlinear Dynamics Measurements at the EBS Storage Ring

octupole, simulation, kicker, injection

116

N. Carmignani, L.R. Carver, L. Hoummi, S.M. Liuzzo, T.P. Perron, S.M. White
ESRF, Grenoble, France

The EBS is a 4th generation synchrotron light source and it has been in user operation since August 2020 at the ESRF. Several measurements to characterise the nonlinear dynamics have been performed in 2023: nonlinear chromaticity, second order dispersion and detuning with amplitude. The results of the measurements are shown and compared with simulations.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P18

About •

Received ※ 23 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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TU4P27

Progress of the HEPS Accelerator Construction and Linac Commissioning

linac, booster, MMI, photon

131

C. Meng, J.S. Cao, Z. Duan, D.Y. He, P. He, H.F. Ji, Y. Jiao, W. Kang, J. Li, J.Y. Li, W.M. Pan, Y.M. Peng, H. Qu, S.K. Tian, G. Xu, H.S. Xu, J. Zhang, J.R. Zhang
IHEP, Beijing, People’s Republic of China
X.H. Lu
IHEP CSNS, Guangdong Province, People’s Republic of China

The High Energy Photon Source (HEPS) is the first fourth-generation synchrotron radiation source in China that has been on the track for construction. The accelerator complex of the light source is composed of a 7BA storage ring, a booster injector, a Linac pre-injector, and three transfer lines. In order to provide high-bunch-charge beams for the storage ring, the booster was designed to be capable of both beam acceleration from low injection energy to extraction energy and charge accumulation at the extraction energy by means of accepting electron bunches from the storage ring. The Linac was built using S-band normal conducting structures, and can provide electron beam with pulse charge up to 7 nC. This paper reports the progress of the construction of the accelerators, including the installation of the storage ring, the pre-commissioning tests of the booster, and commissioning of the Linac. In particular, the beam commissioning of the Linac will be introduced in detail.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P27

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Received ※ 29 August 2023 — Revised ※ 29 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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TU4P28

Useful Formulas and Example Parameters Set for the Design of SSMB Storage Rings

radiation, laser, bunching, undulator

135

X.J. Deng, A. Chao, W.-H. Huang, Z.Z. Li, Z. Pan, C.-X. Tang
TUB, Beijing, People’s Republic of China

A promising accelerator light source mechanism called steady-state microbunching (SSMB) has been actively studied in recent years. Here we summarize some important formulas for the design of SSMB storage rings. Generally we group our formulas into two categories, i.e., a longitudinal weak focusing storage ring for a desired radiation wavelength larger than 100 nm, and a transverse-longitudinal coupling, or a generalized longitudinal strong focusing, storage ring for a desired radiation wavelength between 1 nm and 100 nm. In each category, we have presented an example parameters set for the corresponding SSMB storage ring, to generate kW-level infrared, EUV and soft X-ray radiation, respectively.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P28

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Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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TU4P30

Optical Stochastic Cooling in a General Coupled Lattice

damping, undulator, pick-up, radiation

143

X.J. Deng
TUB, Beijing, People’s Republic of China

Here we present a formalism of optical stochastic cooling in a 3D general coupled lattice. The formalism is general, and can treat a variety of damping and diffusion mechanisms within a single framework. We expect the work to be of value for the development of future light source.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P30

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Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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TU4P31

A Recursive Model for Laser-Electron-Radiation Interaction in Insertion Section of SSMB Storage Ring Based on Transverse-Longitudinal Coupling Scheme

laser, radiation, FEL, bunching

147

C.-Y. Tsai
HUST, Wuhan, People’s Republic of China
X.J. Deng
TUB, Beijing, People’s Republic of China

Funding: This work is supported by the Fundamental Research Funds for the Central Universities (HUST) under Project No. 2021GCRC006 and National Natural Science Foundation of China under project No. 12275094.
Recently a mechanism of the steady-state microbunching (SSMB) in a storage ring has been proposed and investigated. The SSMB aims to maintain the same excellent high repetition rate, close to continuous-wave operation, as the storage ring. Moreover, replacing the conventional RF cavity with a laser modulator for longitudinal focusing, the individual electron bunches can be microbunched in a steady state. The microbunched electron bunch train, with individual bunch length comparable to or shorter than the radiation wavelength, can not only produce coherent powerful synchrotron radiations but may also be subject to FEL-like collective instabilities. Our previous analysis was based on the wake-impedance model*. In this paper, we have developed a recursive model for the laser modulator in the SSMB storage ring. In particular, the transverse-longitudinal coupling scheme is assumed**. Equipped with the above matrix formalism, we can construct a recursive model to account for turn-by-turn evolution, including single-particle and second moments. It is possible to obtain a simplified analytical expression to identify the stability regime or tolerance range for non-perfect cancellation.
*C.-Y. Tsai, PRAB 25, 064401 (2022). C.-Y. Tsai, NIMA 1042 (2022) 167454.
**X.J. Deng et al., NIMA 1019 (2021) 165859.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P31

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Received ※ 23 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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TU4P34

Recent Developments of the cSTART Project

injection, electron, lattice, cavity

155

M. Schwarz, A. Bernhard, E. Bründermann, D. El Khechen, B. Härer, A. Malygin, A.-S. Müller, M.J. Nasse, G. Niehues, A.I. Papash, R. Ruprecht, J. Schäfer, M. Schuh, N.J. Smale, P. Wesolowski, C. Widmann
KIT, Karlsruhe, Germany

The combination of a compact storage ring and a laser-plasma accelerator (LPA) can serve as the basis for future compact light sources. One challenge is the large momentum spread (~ 2%) of the electron beams delivered by the LPA. To overcome this challenge, a very large acceptance compact storage ring (VLA-cSR) was designed as part of the compact STorage ring for Accelerator Research and Technology (cSTART) project. The project will be realized at the Karlsruhe Institute of Technology (KIT, Germany). Initially, the Ferninfrarot Linac- Und Test-Experiment (FLUTE), a source of ultra-short bunches, will serve as an injector for the VLA-cSR to benchmark and emulate LPA-like beams. In a second stage, a laser-plasma accelerator will be used as an injector, which is being developed as part of the ATHENA project in collaboration with DESY and the Helmholtz Institute Jena (HIJ). The small facility footprint, the large-momentum spread bunches with charges from 1 pC to 1 nC and lengths from few fs to few ps pose challenges for the lattice design, RF system and beam diagnostics. This contribution summarizes the latest results on these challenges.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P34

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Received ※ 21 August 2023 — Revised ※ 22 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

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WE4P18

Preliminary Design of Higher-order Achromat Lattice for the Upgrade of the Taiwan Photon Source

lattice, emittance, dipole, radiation

184

N.Y. Huang, M.-S. Chiu, P.J. Chou, G.-H. Luo, H.W. Luo, H.-J. Tsai, F.H. Tseng
NSRRC, Hsinchu, Taiwan

We study the upgrade of Taiwan Photon Source (TPS) with energy saving as the prime objective. The upgrade design is dubbed TPS-II. To accommodate the constraints imposed by the existing TPS tunnel, we choose the higher-order achromat (HOA) lattice configuration which is composed of the 5BA and 4BA cells. This HOA lattice produces a natural beam emittance about 131 pm-rad for a 3 GeV, 518.4 m storage ring. The on-momentum dynamic aperture is about 8 mm and the estimated Touschek life time reaches around 5.7 hours at total beam current of 500 mA. As a result of the ultralow beam emittance, the brightness and coherence fraction (CF) of the photon beam are improved with a factor of several tens especially in the photon wavelength around 0.1 nm. The challenges and preliminary results of this HOA lattice design will be presented.

Poster WE4P18 [5.398 MB]

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reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P18

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Received ※ 21 August 2023 — Revised ※ 28 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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WE4P19

Simulation Study of Orbit Correction by Neural Network in Taiwan Photon Source

network, lattice, synchrotron, photon

188

M.-S. Chiu, Y.-S. Cheng, G.-H. Luo, H.-J. Tsai, F.H. Tseng
NSRRC, Hsinchu, Taiwan
C.P. Felix
MCL/ITRI, Hsinchu, Taiwan

Machine learning has been applied in many fields in re-cent decades. Many research articles also presented re-markable achievements in either operation or designing of the particle accelerator. This paper focuses on the simulated orbit correction by neural networks, a subset of machine learning, in Taiwan Photon Source. The training data for the neural network is generated by accelerator toolbox (AT).

Poster WE4P19 [0.843 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P19

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Received ※ 23 August 2023 — Revised ※ 29 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

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WE4P21

Some Beam Dynamic Issues in the HALF Storage Ring

collimation, injection, scattering, operation

196

J.Y. Tang
USTC, SNST, Anhui, People’s Republic of China
Z.H. Bai, T.L. He, G. Liu, Y. Mo, A.X. Wang, P.H. Yang, Z. Zhao
USTC/NSRL, Hefei, Anhui, People’s Republic of China

HALF (Hefei Advanced Light Facility) is a fourth-generation synchrotron light source that just started construction in 2023. With 2.2 GeV in energy, 350 mA in beam current and 86 pm.rad in emittance, the HALF storage ring faces several beam dynamics challenges. This presentation gives the recent study on some of these issues, in particular the beam collimation and the influence and compensation of the insertion devices. For beam collimation, different beam loss mechanisms have been studied, and the Touschek scattering and beam dumping are considered the two major effects in designing the collimation system. Then two collimators with movable horizontal blades and fixed passive vertical blades are being designed, with the main focus on the collimation efficiency and impedance. For the influence of the insertion devices, it is found that some of the long-period undulators have a high impact on the beam dynamic aperture due to low beam energy and originally small dynamic aperture. The local compensation methods for both linear and non-linear effects have been studied. Instead of the traditional compensation method by electrical wires, the method of using two combined magnets with quadrupole and octupole fields at the two ID ends in restoring the dynamic aperture is also studied and compared.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-WE4P21

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Received ※ 23 August 2023 — Revised ※ 30 August 2023 — Accepted ※ 01 September 2023 — Issued ※ 02 December 2023

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TH1D4

Bi-periodic Undulator: Innovative Insertion Device for SOLEIL II

undulator, synchrotron, electron, radiation

228

A. Potet, F. Blache, P. Brunelle, M.-E. Couprie, O. Marcouillé, A. Mary, T. Mutin, A. Nadji, K. Tavakoli, C. de Oliveira
SOLEIL, Gif-sur-Yvette, France

SOLEIL II project will lead to optimize the production of photons by a modification of the present facility. The storage ring will be redesigned to reduce electron beam emittance, increase photon beam flux and brightness, and improve beamline resolution. The number of magnetic elements will be increased and the space reserved for insertion devices will be decreased by 30%. SOLEIL magnetic group searches for solutions to generate different magnetic periods in a smaller space to maintain the full spectral domain. Bi-Periodic undulator is an innovative and compact device allowing the use of two selectable magnetic periodicities by superimposition of magnets. The magnetic period can be switched from one value to its triple value by mechanical shift of magnetic arrays. A magnetic design has been performed and the construction of a prototype, including magnetic measurements and corrections, is under progress. The prototype will be installed in the storage ring with the goal to verify the feasibility of the model and to characterize the system. The magnetic fields, the radiation produced and the electron beam dynamics will be considered to have a complete knowledge on this undulator.

Slides TH1D4 [2.442 MB]

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reference for this paper ※ doi:10.18429/JACoW-FLS2023-TH1D4

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Received ※ 23 August 2023 — Revised ※ 26 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

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