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MOA2PL03 Review of New Developments in Superconducting Undulator Technology at the APS undulator, FEL, storage-ring, vacuum 1
 
  • J.D. Fuerst, E. Gluskin, Q.B. Hasse, Y. Ivanyushenkov, M. Kasa, I. Kesgin, Y. Shiroyanagi
    ANL, Argonne, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
Superconducting undulator (SCU) technology offers the possibility of enhancing the magnetic field of undulators compared to other undulator technologies. It also allows for the fabrication of circular polarizing devices in addition to the planar undulators. Work on SCUs therefore continues in the light source community. Recent developments in SCU technology will be presented. 		 
slides icon Slides MOA2PL03 [1.669 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-MOA2PL03  
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MOP1WA02 The LCLS-II-HE, A High Energy Upgrade of the LCLS-II FEL, linac, SRF, cryomodule 6
 
  • T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  
  The LCLS-II XFEL will be based on a 4 GeV CW SRF linac and will produce x-ray pulses at 1 MHz over the spectral range of 200 to 5,00 eV. The rf gun will be installed and tested in early 2018; cryomodules are being produced at Fermilab and Jefferson lab and shipped to SLAC; undulator segments are being fabricated at LBNL and measured at SLAC. In parallel, a High Energy upgrade will be described which would extend the linac to 8 GeV and increase the spectral range to 12.8 keV.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-MOP1WA02  
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MOP1WB01 Lattice Design for PETRA IV: Towards a Diffraction-Limited Storage Ring lattice, emittance, undulator, dynamic-aperture 12
 
  • I.V. Agapov, R. Brinkmann, Y.-C. Chae, X.N. Gavaldà, J. Keil, R. Wanzenberg
    DESY, Hamburg, Germany
  
  Machine design for the PETRA III storage ring upgrade – PETRA IV – aiming at a 10-30 pm emittance range has been ongoing at DESY. We present the design challenges and approaches for this machine, the baseline lattice and the alternative lattice concepts currently under consideration.  
slides icon Slides MOP1WB01 [3.259 MB]  
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MOP1WB03 Current and Future of Storage Ring Based Light Sources in KEK emittance, lattice, dynamic-aperture, photon 17
 
  • N. Higashi, K. Harada, T. Honda, Y. Kobayashi, N. Nakamura
    KEK, Ibaraki, Japan
  • K. Hirano
    Hiroshima University, Graduate School of Science, Higashi-Hiroshima, Japan
  
  KEK has two storage-ring light sources. One is Photon Factory (PF). This is the first storage-ring light source in X-ray region in Japan, and the user-run started in 1983. The ring energy is 2.5 GeV, and the emittance has been reduced to 36 nm·rad from 460 nm·rad through some improvements. Another is Photon Factory Advanced Ring (PF-AR). The ring energy is 6.5 GeV, and the single-bunch operation and hard X-ray are featured. The user-run started in 1987, and the emittance is 293 nm·rad. The magnetic lattice is almost the same as the original one. Now we consider the future plans of KEK light sources. One is the fully new facility applying DQBA lattice, named KEK-LS. The circumstance is 571 m, and the emittance is 315 pm·rad @ 3 GeV and 500 mA. In parallel with that, two plans of the only replacements of the lattices reusing existing tunnels of PF and PF-AR are considered. For the PF upgrade, only the arc lattice will be replaced with a new lattice employing combined bends, and the emittance will be improved to 8 nm·rad from 35 nm·rad. For the PF-AR update, fully replacement will be carried out with a new HMBA lattice, and the expected emittance is 520 pm·rad @ 3 GeV and 500 mA.  
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MOP2WB01 Accelerator Physics Studies for the High Energy Photon Source (HEPS) in Beijing lattice, emittance, storage-ring, booster 22
 
  • Y. Jiao, X. Cui, Z. Duan, Y.Y. Guo, D. Ji, J.Y. Li, X.Y. Li, Y.M. Peng, Q. Qin, S.K. Tian, J.Q. Wang, N. Wang, Y. Wei, G. Xu, H.S. Xu, F. Yan, C.H. Yu, Y.L. Zhao
    IHEP, Beijing, People's Republic of China
  
  The High Energy Photon Source (HEPS) is the next ring-based light source with an emittance of tens of picometers, and a circumference of about 1.3 km to be built in China soon in a few years. After 10 years' evolution, the design for the High Energy Photon Source is recently bascially determined. We will report the lattice design and physics studies on HEPS, covering issues of storage lattice design and optimization, booster design, injection design, collective effects, error study, insertion device effects, longitudinal dynamics, etc.  
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MOP2WB04 Study of Multi-bend Achromat Lattices for the HALS Diffraction-limited Storage Ring lattice, storage-ring, sextupole, emittance 25
 
  • Z.H. Bai, L. Wang
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  
  In this paper, two multi-bend achromat (MBA) lattice concepts, the locally symmetric MBA and MBA with interleaved dispersion bumps, are described, which have been used to design the Hefei Advanced Light Source (HALS), a soft X-ray diffraction-limited storage ring proposed at NSRL. In these two MBA concepts, most of the nonlinear effects caused by sextupoles can be cancelled out within one lattice cell as in the hybrid MBA proposed by ESRF EBS, but the available family number of sextupoles in one cell can be more than that in the hybrid MBA so that, for example, the tune shift with momentum can be better controlled to increase the dynamic momentum aperture (MA). Using the two MBA concepts, three kinds of lattices, 8BA, 6BA and 7BA, have been studied for the HALS, showing large on- and off-momentum dynamic apertures and large enough dynamic MA.  
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TUA2WB02 Multi-Bend Lattice Analysis Towards a Diffraction Limited Ring Based Light Source lattice, dipole, emittance, insertion 28
 
  • E. Karantzoulis
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  
  An analysis of lattice configurations up to 10 bend achromat is presented aiming towards diffraction limited ring based light source. The described analysis can apply to any type of a ring based light source however for practical reasons we consider Elettra that has been operating for users for 24 years; to stay competitive for world-class photon science in the future a massive upgrade of the storage ring is needed. The optimum solution is based on certain design criteria, constraints regarding certain accelerator components and their implications on beam dynamics and user requirements. The space available for insertion devices as well as the impact of anti-bends on the design is also addressed. Two proposed realistic lattices are further discussed taking into account different criteria and user requirements. Those lattices reduce the emittance of the present machine by more than one order of magnitude but at the same time respect many other criteria such as realistic magnet gradients, magnets with magnetic length equal to the physical length, drift space enough for radiation extraction, large available space for insertion devices, minimal shift of the beam lines etc.  
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TUA2WB04 Ion Instability in the HEPS Storage Ring electron, simulation, storage-ring, emittance 34
 
  • S.K. Tian, N. Wang
    IHEP, Beijing, People's Republic of China
  
  The High Energy Photon Source (HEPS), a kilometre scale storage ring light source, with a beam energy of 6 GeV and transverse emittances of a few tens of pm.rad, is to be built in Beijing and now is under design. We investigate the ion instability in the storage ring with high beam intensity and low-emittance. We performe a weak-strong simulation to show characteristic phenomena of the instability in the storage ring.  
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TUP1WD02 A Study on the Improved Cavity Bunch Length Monitor for FEL cavity, simulation, FEL, electron 39
 
  • Q. Wang, X.Y. Liu, P. Lu, Q. Luo, B.G. Sun, L.L. Tang, J.H. Wei, F.F. Wu, Y.L. Yang, T.Y. Zhou, Z.R. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  
  Funding: Supported by The National Key Research and Development Program of China (2016YFA0401900), NSFC (11375178, 11575181) and the Fundamental Research Funds for the Central Universities (WK2310000046)
Bunch length monitors based on cavities have great potential especially for future high quality beam sources because of many advantages such as simple structure, wide application rage, and high signal-to-noise ratio (SNR). The traditional way to measure bunch length needs two cavities at least. One is reference cavity, whose function is to get the beam intensity. The other one is defined as main cavity, which is used to calculate the bunch length. There are some drawbacks. To improve performance, the mode and the cavity shape are changed. At the same time, the position and orientation of coaxial probe are designed to avoid interference modes which come from the cavity and beam tube according to the analytic formula of the electromagnetic field distribution. A series simulation based on CST is performed to verify the feasibility, and the simulation results reveal that the improved monitor shows good performance in bunch length measurement. 		 
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TUP1WD03 The Development and Applications of the Digital BPM Signal Processor at SINAP cavity, FEL, SRF, brilliance 43
 
  • L.W. Lai, S.S. Cao, F.Z. Chen, Y.B. Leng, Y.B. Yan, W.M. Zhou
    SSRF, Shanghai, People's Republic of China
  • J. Chen, Y.B. Leng, Y.B. Yan, W.M. Zhou
    SINAP, Shanghai, People's Republic of China
  
  BPM signal processor is one of key beam diagnostics instruments. It has been progressing from analog to digital. The current major processors are digital BPM signal processor (DBPM). Except for some commercial products on-the-shelf, several laboratories developed in-house DBPMs for their own facilities. SINAP started the DBPM development since 2009, when the SSRF phase-I has been completed. After years of optimization, the DBPM has been used in large-scale on some facilities, including SSRF, DCLS and SXFEL. At the same time, some extended functions have been developed to meet special applications on accelerator based on the hardware platform. This topic will introduce the development and applications of the DBPM at SINAP, also the future DBPM development for next generation light source will be discussed here.  
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TUP2WD03 Turn-by-Turn Measurements for Systematic Investigations of the Micro-Bunching Instability detector, radiation, synchrotron, diagnostics 46
 
  • J.L. Steinmann, M. Brosi, E. Bründermann, M. Caselle, S. Funkner, B. Kehrer, A.-S. Müller, M.J. Nasse, G. Niehues, L. Rota, M. Schuh, P. Schönfeldt, M. Siegel, M. Weber
    KIT, Karlsruhe, Germany
  
  Funding: Funded by the German Federal Ministry of Education and Research (Grant No. 05K16VKA) & Initiative and Networking Fund of the Helmholtz Association (contract number: VH-NG-320).
While recent diffraction-limited storage rings provide bunches with transverse dimensions smaller than the wavelength of the observed synchrotron radiation, the bunch compression in the longitudinal plane is still challenging. The benefit would be single cycle pulses of coherent radiation with many orders of magnitude higher intensity. However, the self-interaction of a short electron bunch with its emitted coherent radiation can lead to micro-bunching instabilities. This effect limits the bunch compression in storage rings currently to the picosecond range. In that range, the bunches emit coherent THz radiation corresponding to their bunch length. In this paper, new measurement setups developed at the Karlsruhe Institute of Technology are described for systematic turn-by-turn investigations of the micro-bunching instability. They lead to a better understanding thereof and enable appropriate observation methods in future efforts of controlling and mastering the instability. Furthermore, the described setups might also be used as high repetition rate bunch compression monitors for bunches of picosecond length and below. 		 
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TUP2WD04 Preliminary Design of HEPS Storge Ring Vacuum Chambers and Components vacuum, storage-ring, radiation, photon 52
 
  • P. He, B. Deng, D.Z. Guo, Q. Li, B.Q. Liu, Y. Ma, Y.C. Yang, L. Zhang
    IHEP, Beijing, People's Republic of China
  • X.J. Wang
    Institute of High Energy Physics (IHEP), People's Republic of China
  
  In the design process of HEPS vacuum system, we meet the following limitations. Vacuum chamber must fit inside multipole magnet bore diameter of 25mm (without touching). Water channels and x-ray extraction ports must pass through a 11mm vertical pole gap. Provide an average pressure of 1nTorr during operations with 200mA beam current. Control thermal drift of BPM to ~μm and vibration amplitude ~nm level. Minimize impedance effects. This paper introduces the design of various vacuum chambers, including material selection, mechanical simulation analysis, welding test and so on.  
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TUA2WC01 Transportation and Manipulation of a Laser Plasma Acceleration Beam electron, laser, undulator, plasma 56
 
  • A. Ghaith, T. André, I.A. Andriyash, F. Blache, F. Bouvet, F. Briquez, M.-E. Couprie, Y. Dietrich, J.P. Duval, C. Herbeaux, N. Hubert, C.A. Kitegi, M. Labat, N. Leclercq, A. Lestrade, A. Loulergue, O. Marcouillé, F. Marteau, D. Oumbarek, P. Rommeluère, E. Roussel, M. Sebdaoui, K.T. Tavakoli, M. Valléau
    SOLEIL, Gif-sur-Yvette, France
  • S. Bielawski, C. Evain, C. Szwaj
    PhLAM/CERLA, Villeneuve d'Ascq, France
  • S. Corde, J. Gautier, G. Lambert, B. Mahieu, V. Malka, K.T. Phuoc, C. Thaury
    LOA, Palaiseau, France
  
  Funding: European Research Council advanced grant COXINEL - 340015
The ERC Advanced Grant COXINEL aims at demonstrating free electron laser amplification, at a resonant wavelength of 200 nm, based on a laser plasma acceleration source. To achieve the amplification, a 10 m long dedicated transport line was designed to manipulate the beam qualities. It starts with a triplet of permanent magnet with tunable gradient quadrupoles (QUAPEVA) that handles the highly divergent electron beam, a demixing chicane with a slit to reduce the energy spread per slice, and a set of electromagnetic quadrupoles to provide a chromatic focusing in a 2 m long cryogenic undulator. Electrons of energy 176 MeV were successfully transported throughout the line, where the beam positioning and dispersion were controlled efficiently thanks to a specific beam based alignment method, as well as the energy range by varying the slit width. Observations of undulator radiation for different undulator gaps are reported. 		 
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TUA2WC02 "LWFA-driven" Free Electron Laser for ELI-Beamlines electron, FEL, undulator, photon 62
 
  • A.Y. Molodozhentsev, G. Korn, L. Pribyl
    Czech Republic Academy of Sciences, Institute of Physics, Prague, Czech Republic
  • A.R. Maier
    University of Hamburg, Hamburg, Germany
  
  Free-electron lasers (FEL) are unique light source for different applications on the femto-second scale, including for instance the most basic reaction mechanisms in chemistry, structural biology and condense physics. Laser wake field acceleration (LWFA) mechanism allow to produce extremely short electron bunches of a few fs length with the energy up to a few GeV providing peak current of many kA in extremely compact geometries. This novel acceleration method therefore opens a new way to develop compact "laser-based" FELs. ELI beamlines is an international user facility for fundamental and applied research using ultra-intense lasers and ultra-short high-energy electron beams. In frame of this report we present conceptual solutions for an compact "LFWA" based soft X-ray FEL, which can deliver a photon peak brightness of 1031 ph/sec/mm2/mrad2/0.1%bw. A combination of this achievement with novel laser technologies will open a new perspective for the development of extremely compact FELs with few or even sub-femtosecond photon bunches for a very wide user community.  
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TUP2WA03 Harmonic Lasing in X-Ray FELs: Theory and Experiment FEL, undulator, electron, radiation 68
 
  • E. Schneidmiller, B. Faatz, M. Kuhlmann, J. Rönsch-Schulenburg, S. Schreiber, M. Tischer, M.V. Yurkov
    DESY, Hamburg, Germany
  
  Harmonic lasing in XFELs is an opportunity to extend operating range of existing and planned X-ray FEL user facilities*. Contrary to nonlinear harmonic generation, harmonic lasing can provide much more intense, stable, and narrow-band FEL beam which is easier to handle due to the suppressed fundamental. Another interesting application of harmonic lasing is Harmonic Lasing Self-Seeded (HLSS) FEL*,** that allows to improve longitudinal coherence and spectral power of a SASE FEL. Recently*** this concept was successfully tested at FLASH2 in the range 4.5 - 15 nm. That was also the first experimental demonstration of harmonic lasing in a high-gain FEL and at a short wavelength (before it worked only in infrared FEL oscillators). In this contribution we describe the concepts of harmonic lasing and of HLSS FEL, and present the experimental results from FLASH2.
* E.Schneidmiller and M.Yurkov, Phys. Rev. ST-AB 15(2012)080702
** E.Schneidmiller and M.Yurkov, Proc. of FEL2013, p.700
*** E.Schneidmiller et al., Phys. Rev. Accel. Beams 20(2017)020705 		 
slides icon Slides TUP2WA03 [3.378 MB]  
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WEA1PL02 Dielectric Accelerators and Other Non-Plasma Accelerator Based Compact Light Sources laser, undulator, electron, radiation 74
 
  • R.J. England, Z. Huang
    SLAC, Menlo Park, California, USA
  
  Funding: U.S. Department of Energy DE-AC02-76SF00515; Gordon and Betty Moore Foundation GBMF4744
We review recent experimental progress in developing nanofabricated dielectric laser-driven accelerators and discuss the possibility of utilizing the unique sub-femtosecond electron pulse format these accelerators would provide to create ultra-compact EUV and X-ray radiation sources. 		 
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WEA1PL03 Attosecond Timing laser, timing, FEL, electron 79
 
  • F.X. Kärtner
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • K. Shafak
    CFEL, Hamburg, Germany
  • K. Shafak
    Cycle GmbH, Hamburg, Germany
  • M. Xin
    DESY, Hamburg, Germany
  
  Funding: This work was supported by DESY and the European Research Council under the European Union's Seventh Framework Program (FP/2007-2013) / ERC Grant Agreement No. 609920.
Photon-science facilities such as X-ray free-electron lasers (XFELs) and intense-laser facilities are emerging world-wide with some of them producing sub-fs X-ray pulses. These facilities are in need of a high-precision timing distribution system, which can synchronize various microwave and optical sub-sources across multi-km distances with attosecond precision. Here, we report on a synchronous laser-microwave network that permits attosecond precision across km-scale distances. This was achieved by developing new ultrafast timing metrology devices and carefully balancing the fiber nonlinearities and fundamental noise contributions in the system. New polarization-noise-suppressed balanced optical crosscorrelators and free-space-coupled balanced optical-microwave phase detectors for improved noise performance have been implemented. Residual second- and third-order dispersion in the fiber links are carefully compensated with additional dispersion-compensating fiber to suppress link-induced Gordon-Haus jitter and to minimize output pulse duration; the link power is stabilized to minimize the nonlinearity-induced jitter as well as to maximize the signal to noise ratio for locking. 		 
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WEP1WC02 CompactLight Design Study undulator, electron, FEL, gun 85
 
  • A. Latina, D. Schulte, S. Stapnes, W. Wuensch
    CERN, Geneva, Switzerland
  • M. Aicheler
    HIP, University of Helsinki, Finland
  • A.A. Aksoy
    Ankara University Institute of Accelerator Technologies, Golbasi, Turkey
  • A. Bernhard
    KIT, Karlsruhe, Germany
  • J.A. Clarke
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • A.W. Cross
    USTRAT/SUPA, Glasgow, United Kingdom
  • G. D'Auria, R. Geometrante
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • R.T. Dowd
    AS - ANSTO, Clayton, Australia
  • D. Esperante Pereira
    IFIC, Valencia, Spain
  • W. Fang
    SINAP, Shanghai, People's Republic of China
  • A. Faus-Golfe
    LAL, Orsay, France
  • M. Ferrario
    INFN/LNF, Frascati (Roma), Italy
  • E.N. Gazis
    National Technical University of Athens, Athens, Greece
  • R. Geometrante
    KYMA, Trieste, Italy
  • M. Jacewicz
    Uppsala University, Uppsala, Sweden
  • A. Mostacci
    Sapienza University of Rome, Rome, Italy
  • F. Nguyen
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • F. Pérez
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  • J.M.A. Priem
    VDL ETG, Eindhoven, The Netherlands
  • T. Schmidt
    PSI, Villigen PSI, Switzerland
  
  H2020 CompactLight Project aims at designing the next generation of compact hard X-Rays Free-Electron Lasers, relying on very high accelerating gradients and on novel undulator concepts. CompactLight intends to design a compact Hard X-ray FEL facility based on very high-gradient acceleration in the X band of frequencies, on a very bright photo injector, and on short-period/superconductive undulators to enable smaller electron beam energy. If compared to existing facilities, the proposed facility will benefit from a lower electron beam energy, due to the enhanced undulators performance, be significantly more compact, as a consequence both of the lower energy and of the high-gradient X-band structures, have lower electrical power demand and a smaller footprint. CompactLight is a consortium of 24 institutes (21 European + 3 extra Europeans), gathering the world-leading experts both in the domains of X-band acceleration and undulator design.  
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WEA2WD01 QUAPEVA: Variable High Gradient Permanent Magnet Quadrupole quadrupole, laser, electron, multipole 89
 
  • C.A. Kitegi, T. André, M.-E. Couprie, A. Ghaith, J. Idam, A. Loulergue, F. Marteau, D. Oumbarek, M. Sebdaoui, M. Valléau, J. Vétéran
    SOLEIL, Gif-sur-Yvette, France
  • C. Benabderrahmane, J. Chavanne, G. Le Bec
    ESRF, Grenoble, France
  • O. Cosson, F. Forest, P. Jivkov, J.L. Lancelot
    Sigmaphi, Vannes, France
  • P. N'gotta
    MAX IV Laboratory, Lund University, Lund, Sweden
  • C. Vallerand
    LAL, Orsay, France
  
  We present the magnetic and the mechanical design of tunable high gradient permanent magnet (PM) quadrupoles. The tunable gradient of the so-called QUAPEVAS extends from 100T/m up to 200T/m. Seven of them with various lengths, ranging from 26mm up to 100mm, for different integrated quadrupole strengths were manufactured. The measured magnetic performance of these devices is also reported. These devices were successfully developed to transport laser plasma accelerated electron beam. Such applications have however less stringent multipole harmonic content constraints than diffraction limited Light sources. Trails for lowering the multipole harmonics will be discussed.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEA2WD01  
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WEA2WD03 Analysis of Electron Trajectories in Harmonic Undulator with SCILAB's Model Based Design Codes undulator, simulation, electron, FEL 93
 
  • H. Jeevakhan, S. Kumar
    NITTTR, Bhopal, India
  • G. Mishra
    Devi Ahilya University, Indore, India
  
  Scilab's X-cos model-based simulation blocks has been used to simulate the trajectories of an electron traversing through an Harmonic undulator. The trajectory of electron along X and Y directions has been simulated from Numerical and analytical methods. Analysis given in the present paper is compared with the other codes. Parallel simulation of Harmonic undulator magnetic field along with trajectories of electron is given in the present analysis.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEA2WD03  
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WEA2WD04 Harmonic Undulator Radiation with Dual Non Periodic Magnetic Components undulator, electron, radiation, FEL 98
 
  • H. Jeevakhan
    NITTTR, Bhopal, India
  • G. Mishra
    Devi Ahilya University, Indore, India
  
  Undulator radiation at third harmonics generated by harmonic undulator in the presence dual non periodic constant magnetic field. Electron trajectories along the x and y direction has been determined analytical and numerical methods. Generalized Bessel function is used to determine the intensity of radiation and Simpson's numerical method of integration is used to find the effect of constant magnetic fields. Comparison with previous analysis has also been presented.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEA2WD04  
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WEP2PT003 Undulator Phase Matching for the the European XFEL undulator, FEL, electron, radiation 103
 
  • Y. Li, J. Pflüger
    XFEL. EU, Hamburg, Germany
  
  The undulator system in the European XFEL is mainly comprised 5-m long undulator segments and 1.1 m long intersections in between. In intersections the electron velocity is faster than it inside an undulator and the optical phase is detuned. The detune effect is also from the undulator fringe field where electron longitudinal speed also deviates from the oscillation condition. The total detune effect is compensated by a magnetic device called phase shifter, which is correspondingly set for a specific undulator gap. In this paper we introduce the method to set the phase shifter gap for each K parameter according to the measured magnetic field.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT003  
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WEP2PT008 Microbunching Instability Study in the Linac-Driven FERMI FEL Spreader Beam Line linac, laser, FEL, electron 108
 
  • S. Di Mitri, S. Spampinati
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  
  Suppression of microbunching instability (MBI) along high brightness electron beam delivery systems is a priority for Free Electron lasers (FELs) aiming at very narrow bandwidth. The impact of MBI on FEL spectral brilliance is aggravated by the growing demand for multi-user FEL facilities, which adopt multi-bend switchyard lines traversed by high charge density electron beams. This study provides practical guidelines to switchyards design largely immune to MBI, by focusing on the FERMI FEL Spreader line. First, two MBI analytical models [1, 2] are successfully benchmarked along the accelerator. Being the second model flexible enough to describe an arbitrary multi-bend line, and found it in agreement with particle tracking and experimental results, it was used to demonstrate that a newly proposed Spreader optics provides unitary MBI gain while preserving the electron beam brightness.
[1] Z. Huang and K.-J. Kim, Phys. Rev. Special Topics - Accel. Beams 5, 074401 (2002)
[2] R.A. Bosch, K.J. Kleman, and J. Wu, Phys. Rev. Special Topics - Accel. Beams 11, 090702 (2008) 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT008  
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WEP2PT014 Strong Focusing Lattice Design for SSMB lattice, photon, dipole, electron 113
 
  • T. Rui, X.J. Deng, W.-H. Huang, C.-X. Tang
    TUB, Beijing, People's Republic of China
  • A. Chao
    SLAC, Menlo Park, California, USA
  
  A storage ring applicable for SSMB operation is a critical part of a high average power SSMB EUV light source. A lattice for SSMB based on longitudinal strong focusing is under design in Tsinghua University. To generate and maintain micro-bunching in a storage ring in this scenario, the momentum compaction has to be small. A lattice with low momentum compaction factor is presented in this work. The lattice of the current design consists of two MBA cells with isochronous unit cells to minimize local and global momentum compaction, and two straight sections for insertion devices. The design energy of the ring is 400MeV and the circumference is 94 meters. Nonlinear effects such as higher order momentum compactions will continue to be optimized.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT014  
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WEP2PT021 The Design and Test of a Stripline Kicker for HEPS kicker, simulation, impedance, injection 117
 
  • H. Shi, J. Chen, L. Huo, P. Liu, X.L. Shi, G. Wang, L. Wang, N. Wang
    IHEP, Beijing, People's Republic of China
  
  A fast stripline kicker is adopted for High Energy Photon Source (HEPS) on-axis injection. The optimization of a prototype 750 mm long kicker has been finished. The 3D simulation results show the final design of wide vane with end cover lowers the beam loss about 31% than the original design does. We develop a feedthrough model with machinable glass ceramic and achieve a VSWR under 1.3 in 0~2 GHz. The assembly of kicker and commercial feedthroughs has been tested with Keysight E5071C. The testing results of S parameters and TDR value show a good agreement with simulation ones.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT021  
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WEP2PT022 PHASE SHIFTER APPLICATION IN DOUBLE UNDULATOR CONFIGURATION OF HEPS undulator, brilliance, radiation, electron 120
 
  • X.Y. Li, Y. Jiao, S.K. Tian
    IHEP, Beijing, People's Republic of China
  
  For over 6 meters long straight-section of HEPS, collinear double-cryogenic permanent magnet undulator(CPMU) is designed for high energy photon users to achieve higher brightness. Angular and spatial profiles of radiation produced by the double undulator configuration have been derived analytically. The efficiency of phase shifter on improving the brightness of double-CPMU is therefore evaluated with the beam energy spread and emittance are taken into account. Optimized beta-functions of electron beam are obtained.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT022  
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WEP2PT023 Preparation and Characterization of Non-Evaporable Ti-Zr-V Getter Films for HEPS vacuum, site, experiment, radiation 125
 
  • Y. Ma, D.Z. Guo, P. He, B. Liu, Y.C. Yang
    IHEP, Beijing, People's Republic of China
  
  For the low activation temperature and high pumping speed, surface pumping capacity, the TiZrV coatings were chosen to high energy photo source (HEPS). Films of TiZrV alloy have been deposited on 1.5 meter long, cylindrical vacuum chambers of 22mm diameter copper substrates in krypton ambient using DC magnetron sputtering system. Film composition, the activation temperature and pumping properties have been investigated in order to optimize the deposition parameters for vacuum applications. The films were also studied using the X-ray photo-emission electron spectroscopy (XPS) after annealing them at different temperatures ranging from 120°C to 300°C for two hours in ultra-high vacuum environment. Pumping speed and surface pumping capacity testing facilities were also being constructed to investigate the characterization of TiZrV.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT023  
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WEP2PT024 Influences of Harmonic Cavities on the Single-Bunch Instabilities in Electron Storage Rings cavity, impedance, operation, 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  
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WEP2PT030 Undulator Development Activities at DAVV-Indore undulator, radiation, synchrotron, synchrotron-radiation 133
 
  • M. Gehlot, R. Khullar, G. Mishra
    Devi Ahilya University, Indore, India
  • H. Jeevakhan
    NITTTR, Bhopal, India
  • G. Sharma
    RI Research Instruments GmbH, Bergisch Gladbach, Germany
  
  Insertion Device Design Laboratory, DAVV has development activities on in-house design, fabrication and measurement of prototype undulators for synchrotron radiation and free electron laser application. The first prototype U50 was built with six periods, 50mm each period. It was PPM type. The next prototype U20 hybrid device based on NdFeB-Cobalt steel was built with aim to produce 0.24T to 0.05T in 10-20mm gap. The undulator is a 20mm period and there are 25 periods. The next one is U50-II PPM structure with 20 periods. In this paper we review the designs of all these undulators and briefly outline the user facilities of Hall probe bench, Pulsed wire bench and stretched wire magnetic measurement systems at IDDL.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT030  
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WEP2PT032 Feasibility Study of High Energy X-Ray Source at PLS-II wiggler, insertion, insertion-device, quadrupole 138
 
  • J.H. Han, J. Lee, S.B. Lee, S.J. Lee, T.-Y. Lee
    PAL, Pohang, Kyungbuk, Republic of Korea
  
  PLS-II operates for user service with the 34 beamlines since 2012. For engineering applications, especially for thick metal samples, a high energy X-ray beamline is under consideration to cover a photon energy up to §I{100}{keV} or beyond. By comparing the radiation spectra from various insertion devices types, superconducting wiggler was found to be a most promising candidate. A feasibility study to install the high field wiggler in the PLS-II ring is presented in this paper. Electron beam dynamics studies for a minimum impact on the electron beam parameters and engineering consideration to add more magnets are carried out.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT032  
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WEP2PT033 Conceptual Design of Superconducting Transverse Gradient Undulator for PAL-XFEL Beamline FEL, undulator, operation, 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. 		 
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WEP2PT034 Beyond Uniform Ellipsoidal Laser Shaping for Beam Brightness Improvements at PITZ laser, emittance, flattop, simulation 146
 
  • H.J. Qian, J.D. Good, C. Koschitzki, M. Krasilnikov, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  
  In the last decades, photoinjector brightness has improved significantly, driven by the needs of free electron lasers and many other applications. One of the key elements is photocathode laser shaping for reducing emittance growth from nonlinear space charge forces. At the photoinjector test facility at DESY in Zeuthen (PITZ), a uniform flattop laser was used to achieve record low emittance for a bunch charge from 20 pC to 1 nC. Due to the ideal 3D space charge force linearization in ellipsoidal electron bunches, uniform ellipsoidal photocathode laser shaping were proposed to improve beam emittance up to 33% for 1 nC beam at PITZ. In this paper, we will show even further transverse emittance improvements in simulations for both flattop and ellipsoidal laser pulses with parabolic radial distribution, versus uniform distributions. The laser shaping effects on longitudinal phase space are also discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT034  
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WEP2PT038 Conceptual Design for SLS-2 lattice, vacuum, quadrupole, emittance 150
 
  • M.M. Dehler, A. Citterio, T. Garvey, M. Hahn, M. Negrazus, L. Schulz, A. Streun, V. Vranković
    PSI, Villigen PSI, Switzerland
  
  After 17 years of user operation, we plan to do an upgrade of the Swiss Light Source (SLS) for the period of 2021-2024. The entire storage ring will be replaced with a new layout allowing operation at emittances lowered by factors of 40-50. This is made possible to one part by small aperture magnets allowing for a multi bend achromat design and to the other - a special feature for SLS-2 - reverse bends combined with longitudinal gradient bends (LGB) leading to zero dispersion at the maximum magnetic field, thus minimizing the quantum excitation of the beam due to synchrotron radiation. The compact magnet layout makes use of offset quadrupoles, combined function magnets and longitudinal gradient bends. The chamber with a cross section of 20 mm will be fully NEG coated to ensure good pumping and a quick vacuum conditioning. Numerical simulation of instability thresholds has been performed, we expect values in the order of 2 mA for the single bunch current.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT038  
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WEP2PT050 Status of CAEP THz Free Electron Laser Oscillator FEL, electron, laser, free-electron-laser 154
 
  • M. Li, T.H. He, C.L. Lao, P. Li, S.F. Lin, X. Luo, Q. Pan, L.J. Shan, X. Shen, H. Wang, J. Wang, D. Wu, D.X. Xiao, Y. Xu, X. Yang, P. Zhang, K. Zhou
    CAEP/IAE, Mianyang, Sichuan, People's Republic of China
  
  China Academy of Engineering Physics tera-hertz free electron laser (CAEP THz FEL, CTFEL) is the first THz FEL oscillator in China, which was jointly built by CAEP, Peking university and Tsinghua university. The stimulated saturation of the CTFEL was reached in August, 2017. This THz FEL facility consists of a GaAs photocathode high-voltage DC gun, a superconducting RF linac, a planar undulator and a quasi-concentric optical resonator. The terahertz laser's frequency is continuous adjustable from 2 THz to 3 THz. The average power is more than 10 W and the micro-pulse power is more than 0.1 MW.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-WEP2PT050  
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THA1WA03 GPT-CSR: A New Simulation Code for CSR Effects simulation, radiation, bunching, electron 157
 
  • S.B. van der Geer, M.J. de Loos
    Pulsar Physics, Eindhoven, The Netherlands
  • I. Setija, P.W. Smorenburg
    ASML Netherlands B.V., Veldhoven, The Netherlands
  • P.H. Williams
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  
  For future applications of high-brightness electron beams, including the design of next generation FEL's, correct correct simulation of Coherent Synchrotron Radiation (CSR) is essential as it potentially degrades beam quality to unacceptable levels. However, the long interaction lengths compared to the bunch length, numerical cancellation, and difficult 3D retardation conditions make accurate simulation of CSR effects notoriously difficult. To ease the computational burden, CSR codes often make severe simplifications such as an ultra relativistic bunch travelling on a prescribed reference trajectory. Here we report on a new CSR model, implemented in the General Particle Tracer (GPT) code, that avoids most of the usual assumptions: It directly evaluates the Lienard-Wiechert potentials based on the stored history of the beam, it makes no assumptions about reference trajectories, while also taking into account the transverse size of the beam. First results demonstrating microbunching gain in a chicane are presented.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THA1WA03  
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THP1WB02 Impedance Evaluation of PF In-Vacuum Undulator (IVU) with Theories and Simulations and Experimental Confirmation of them by the Tune Measurement impedance, simulation, undulator, vacuum 160
 
  • O. Tanaka, N. Nakamura, T. Obina, K. Tsuchiya
    KEK, Ibaraki, Japan
  
  Four In-Vacuum Undulators (IVU) were recently installed to Photon Factory (PF) at KEK. The estimate of their impedance and kick factors is a very important issue, because they could considerably increase the total impedance of PF. Moreover, the coupling impedance of the IVUs could lead to the beam energy loss, changes in the bunch shape, betatron tune shifts and, finally, to the various beam instabilities. Using the simulation tool (CST Particle Studio), longitudinal and transverse impedances of the IVUs were evaluated and compared to analytical formulas and measurement results. The study provides guidelines for mitigation of unwanted impedance, for an accurate estimate of its effects on the beam quality and beam instabilities and for the impedance budget of a newly designed next-generation machine which has many IVUs and small-aperture beam pipes.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THP1WB02  
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THP2WB02 An Overview of the Progress on SSMB radiation, lattice, storage-ring, focusing 166
 
  • C.-X. Tang, X.J. Deng, W.-H. Huang, T. Rui
    TUB, Beijing, People's Republic of China
  • A. Chao, D.F. Ratner
    SLAC, Menlo Park, California, USA
  • J. Feikes, J. Li, M. Ries
    HZB, Berlin, Germany
  • C. Feng, B.C. Jiang, X.F. Wang
    SINAP, Shanghai, People's Republic of China
  • E. Granados
    MIT, Cambridge, Massachusetts, USA
  • A. Hoehl
    PTB, Berlin, Germany
  
  Steady State Microbunching (SSMB) is an electron stor- age ring based scheme proposed by Ratner and Chao to generate high average power coherent radiation and is one of the promising candidates to address the need of kW level EUV source for lithography. After the idea of SSMB was put forward, it has attracted much attention. Recently, with the promote of Chao, in collaboration with colleagues from other institutes, a SSMB task force has been established in Tsinghua University. The experimental proof of the SSMB principle and a feasible lattice design for EUV SSMB are the two main tasks at this moment. SSMB related physics for the formation and maintenance of microbunches will be explored in the first optical proof-of-principle experiment at the MLS storage ring in Berlin. For EUV SSMB lattice design, longitudinal strong focusing and reversible seeding are the two schemes on which the team focuses. The pro- gresses made as well as some challenges from physical and technological aspects for EUV SSMB will be presented in this paper.
on behalf of the SSMB team: C. Tang, Alex Chao, X. Deng, W. Huang, and T. Rui of THU; D. Ratner of SLAC; J. Feikes and M. Ries of Helmholtz-Zentrum Berlin; C. Feng, B. Jiang, and X. Wang of SINAP 		 
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THP2WB03 Transparent Lattice Characterization with Gated Turn-by-Turn Data of Diagnostic Bunch-Train lattice, operation, 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. 		 
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THP2WB04 Laser Seeding of Electron Bunches for Future Ring-Based Light Sources laser, electron, radiation, storage-ring 177
 
  • S. Khan, B. Büsing, N.M. Lockmann, C. Mai, A. Meyer auf der Heide, B. Riemann, B. Sawadski, M. Schmutzler, P. Ungelenk
    DELTA, Dortmund, Germany
  
  Funding: Funded by BMBF (05K16PEA, 05K16PEB), MERCUR (Pr-2014-0047), DFG (INST 212/236-1 FUGG) and the Land NRW.
In contrast to free-electron lasers (FELs), ring-based light sources are limited in intensity by incoherent emission and in pulse duration by the bunch length. However, FEL seeding schemes can be adopted to generate intense and ultrashort radiation pulses in storage rings by creating laser-induced microbunches within a short slice of the electron bunch. Microbunching gives rise to coherent emission at harmonics of the seed wavelength. In addition, terahertz (THz) radiation is coherently emitted over many turns. At DELTA, a storage ring operated by the TU Dortmund University, coherent harmonic generation (CHG) with single and double 40-fs pulses is routinely performed at seed wavelengths of 800 and 400 nm. Seeding with intensity-modulated pulses to generate tunable narrowband THz radiation is also studied. As a preparation for echo-enabled harmonic generation (EEHG), simultaneous seeding with 800/400-nm pulses in two undulators has been demonstrated. The DELTA storage ring is an excellent testbed to study many aspects of laser seeding and related diagnostics. In addition to short-pulse generation, steady-state microbunching at ring-based light sources will be discussed in the paper. 		 
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THA1WC01 Compact Arc Compressor for FEL-Driven Compton Light Source and ERL-Driven UV FEL FEL, emittance, electron, dipole 183
 
  • S. Di Mitri
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • J.A.G. Akkermans, I. Setija
    ASML Netherlands B.V., Veldhoven, The Netherlands
  • D. Douglas
    JLab, Newport News, Virginia, USA
  • C. Pellegrini
    SLAC, Menlo Park, California, USA
  • G. Penn, M. Placidi
    LBNL, Berkeley, California, USA
  
  Many research and applications areas require photon sources capable of producing extreme ultra-violet (EUV) to gamma-ray beams with reasonably high fluxes and compact footprints. We explore the feasibility of a compact energy-recovery linac EUV free electron laser (FEL)*, and of a multi-MeV gamma-rays source based on inverse Compton scattering from a high intensity UV FEL emitted by the electron beam itself. In the latter scenario, the same electron beam is used to produce gamma-rays in the 10-20 MeV range and UV radiation in the 1015 eV range, in a ~4x22 m2 footprint system.**
* J.Akkermans, S.Di Mitri, D.Douglas, I.Setija, PRAB 20, 080705 (2017).
** M. Placidi, S. Di Mitri,⁎, C. Pellegrini, G. Penn, NIM A 855 (2017) 55-60. 		 
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THA1WC01  
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THP1WD02 LCLS-II Beam Containment System for Radiation Safety electron, cavity, FEL, radiation 187
 
  • C.I. Clarke, J. Bauer, M. Boyes, Y. Feng, A.S. Fisher, R.A. Kadyrov, J.C. Liu, E. Rodriguez, M. Rowen, M. Santana-Leitner, F. Tao, J.J. Welch, S. Xiao
    SLAC, Menlo Park, California, USA
  • T.L. Allison, J. Musson
    JLab, Newport News, Virginia, USA
  
  Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515 and DE-AC05-06OR23177.
LCLS-II is a new xFEL facility under construction at SLAC National Accelerator Laboratory with a superconducting electron linac designed to operate up to §I{1.2}{MW} of beam power. This generates more serious beam hazards than the typical sub-kW linac operation of the existing xFEL facility, Linac Coherent Light Source (LCLS). SLAC uses a set of safety controls termed the Beam Containment System (BCS) to limit beam power and losses to prevent excessive radiation in occupied areas. The high beam power hazards of LCLS-II necessitate the development of new BCS devices and a larger scale deployment than previously done at LCLS. We present the new radiation hazards introduced by LCLS-II and the design development for the BCS. 		 
slides icon Slides THP1WD02 [2.244 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THP1WD02  
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THP2WD01 Construction and Optimization of Cryogenic Undulators at SOLEIL undulator, cryogenics, vacuum, electron 193
 
  • M. Valléau, P. Berteaud, F. Briquez, P. Brunelle, N. Béchu, M.-E. Couprie, J. Da Silva Castro, J.M. Dubuisson, A. Ghaith, C. Herbeaux, J. Idam, C.A. Kitegi, F. Lepage, A. Lestrade, M. Louvet, O. Marcouillé, F. Marteau, A. Mary, A. Nadji, L.S. Nadolski, P. Rommeluère, M. Sebdaoui, A. Somogyi, K.T. Tavakoli, M. Tilmont, T. Weitkamp
    SOLEIL, Gif-sur-Yvette, France
  
  Funding: Synchrotron SOLEIL, L'Orme des Merisiers, 91 192 BP 34 Gif-sur-Yvette, France,
With permanent magnets undulator operation at cryogenic temperature, the magnetic field and the coercivity can be enhanced, enabling shorter periods with high magnetic fields. The first full scale (2 m long, 18 mm period) hybrid cryogenic undulator [1] using PrFeB [2] magnets operating at 77 K was installed at SOLEIL in 2011. Photon spectra measurements, in good agreement with the ex-pectations from magnetic measurements, were used for precise alignment and taper optimization. The second and third 18 mm PrFeB cryogenic undulators, modified to a half-pole/magnet/half-pole structure, were optimized without any magnet or pole shimming after assembly but mechanical sortings and some geometrical corrections had been done before assembly. A systematic error on individual magnets on the third U18 was also compensated. In-situ measurement benches, including a Hall probe and a stretched wire to optimize the undulator field at room and cryogenic temperature are presented. An upgrade of these in-situ benches will be detailed with the fabrication of a 15 mm 3 m long PrFeB cryogenic undulator at SOLEIL.
[1] C. Benabderrahmane, M. Valléau, M. E. Couprie, Phys. Rev. Accel. Beams 20, 033201(2017)
[2] C. Benabderrahmane, M. Valléau, M. E. Couprie, NIMA 669, 1-6, (2012) 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-THP2WD01  
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FRA1PL01 Summary Report: Linac-Based Light Sources FEL, experiment, simulation, linac 199
 
  • T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  • W. Decking
    DESY, Hamburg, Germany
  • L. Giannessi
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • L. Giannessi
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • H.-S. Kang
    PAL, Pohang, Kyungbuk, Republic of Korea
  
  This is the summary report of the linac-based light sources working group.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-FRA1PL01  
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FRA1PL02 Summary of Working Group B: Ring-Based Light Sources emittance, lattice, impedance, injection 202
 
  • R.P. Walker
    DLS, Oxfordshire, United Kingdom
  • Y. Li
    BNL, Upton, Long Island, New York, USA
  • Q. Qin
    IHEP, Beijing, People's Republic of China
  
  This is the summary report of the ring-based light sources working group.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-FLS2018-FRA1PL02  
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