FEL2019 - List of Keywords (gun)

Paper	Title	Other Keywords	Page
TUP012	Smith-Purcell Radiation Emitted by Pico-second Electron Bunches from a 30 keV Photo-Electron Gun	electron, radiation, experiment, laser	66
	M.R. Asakawa, S. Yamaguchi Kansai University, Osaka, Japan
	In this paper, an experiment to generate Smith-Purcell radiation using pico-second electron bunches is reported. The electron bunch was produced by a DC 30 keV photo-electron electron gun driven by a 100 fs Ti:sapphire laser. The charge of the bunch varied from 1 pC to 300 pC by changing the laser power. Smith-Purcell radiation experiment was performed with the central part of the entire electron bunch. Estimation of pulsewidth of the bunch based on the envelope equation showed that the pulsewidth of the bunch at the anode electrode increased from 0.8 ps to 3.2 ps as the bunch charge increase from 0.1 pC to 11 pC. Such electron bunch was traveled along the surface of the metallic grating with a period of 2 mm. The radiation wavelength was estimated to be 4 mm at an obserbation angle of 10 degree. The radiation power was measured by a bolometer and quadraticallly increased with the bunch charge. Numerical simulation of this experiment indicated the enhancement of the harmonic components of the radiation. We are now constructing a THz-TDS system to measure the time-trace of the electric field of the radiation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-TUP012
About •	paper received ※ 14 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEA01	Overview of CW RF Guns for Short Wavelength FELs	cathode, FEL, SRF, electron	290
	H.J. Qian DESY Zeuthen, Zeuthen, Germany E. Vogel DESY, Hamburg, Germany
	Hard X-ray FELs (XFELs) operating with pulsed RF provide unprecedented peak brilliance for scientific research. Operating the accelerators with CW RF improves the flexibility w.r.t. the available time structure for experiments and opens the next frontier of average brilliance. One of the challenges of CW XFELs is the electron source, which requires both CW operation and highest possible beam quality allowing lasing at shortest wavelengths. The CW mode technically constraints the gun acceleration gradient, which is one of the keys to electron source brightness, so R&D is devoted to CW gun improvements since decades. In this contribution, the worldwide development status of CW RF guns, both normal conducting and superconducting, is reviewed.
	Slides WEA01 [16.329 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEA01
About •	paper received ※ 25 August 2019 paper accepted ※ 07 November 2019 issue date ※ 05 November 2019
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WEA04	Growing and Characterization of Cs2Te Photocatodes with Different Thicknesses at INFN LASA	cathode, electron, diagnostics, FEL	297
	L. Monaco, P. Michelato, D. Sertore INFN/LASA, Segrate (MI), Italy G. Guerini Rocco, C. Pagani Università degli Studi di Milano & INFN, Segrate, Italy
	The INFN LASA group has a long standing experience in the production of cesium telluride photocathodes for high brightness photoinjectors. The well-established recipe relies on the deposition of a typical amount of 10 nm of Te, followed by the Cs deposition until reaching the maximum QE. Nevertheless, for improving the understanding of photocathode properties, we are investigating the effect of Te thickness on the growing process, evaluating photocathode optical properties and quantum efficiency during the growing process and on the final film. These photocathodes will be then operated and analyzed in the real environment of the RF Gun at the PITZ facility in DESY Zeuthen, to estimate their impact on the electron beam properties.
	Slides WEA04 [15.703 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEA04
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP026	Preliminary Geometry Optimization of a 3.5-Cell SRF Gun Cavity at ELBE Based on Beam Dynamics	SRF, cavity, emittance, electron	374
	K. Zhou, P. Li CAEP/IAE, Mianyang, Sichuan, People’s Republic of China A. Arnold, S. Ma, J. Schaber, J. Teichert, R. Xiang HZDR, Dresden, Germany
	At present, ELBE radiation source at HZDR is optimizing the SRF cavity for the next generation ELBE SRF GUN. This paper presents a preliminary study on the geometry optimization of a 3.5-cell SRF gun cavity based on beam dynamics. By changing the lengths of the half cell and the first TESLA like cell, two new cavity models with higher electric field in the half cell are built and their RF fields are compared with SRF GUN I and SRF GUN II. Through the scanning of the RF phases and the electric fields, the simulation results indicate that new models have smaller transverse emittance at relatively lower electric field gradients and better performance on longitudinal emittance than SRF GUN I and SRF GUN II.
	Poster WEP026 [1.345 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP026
About •	paper received ※ 19 August 2019 paper accepted ※ 29 August 2019 issue date ※ 05 November 2019
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WEP031	Timing Synchronization Activities for Drift-Free Operation of Ultrafast Electron Diffraction System at KAERI	electron, timing, laser, detector	385
	J. Shin, J. Kim KAIST, Daejeon, Republic of Korea I.H. Baek, Y.U. Jeong, H.W. Kim, K. Oang, S. Park KAERI, Daejon, Republic of Korea
	Funding: This work is funded by KAERI (Grant number: 525350-19) Precise timing synchronization of an ultrafast electron diffraction facility is essential requirement for femtosecond resolution structure analysis. Recent studies of THz-based electron deflectors have enabled the timing drift measurement between ultrafast electrons and an optical pump beam with few femtosecond resolution [1]. In this work, we will introduce timing synchronization activities to suppress the drift of an electron beam. As timing drift of the electron beam originates from every sub-element, each timing drift contribution from RF transfer, RF-to-optical synchronization, and optical amplification is measured. Timing drift of RF transfer through coaxial cable, which exposed to temperature fluctuation, is actively stabilized from 2 ps to 50 fs by active feedback loop. Further additive drift from RF-to-optical synchronization is maintained below 100 fs. Also optical drift due to the regenerative amplifier, measured by optical correlator, is maintained below 20 fs over an hour. This work allows ultrafast electron diffraction system to operate with less drift correction procedure and increased user availability. [1] H. Yang et al., "10-fs-level synchronization of photocathode laser with RF-oscillator for ultrafast electron and X-ray sources", Sci. Rep. 7, 39966 (2017).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP031
About •	paper received ※ 24 August 2019 paper accepted ※ 25 August 2019 issue date ※ 05 November 2019
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WEP047	Update on the Photocathode Lifetime at FLASH and European XFEL	cathode, FEL, laser, operation	427
	S. Lederer, F. Brinker, S. Schreiber DESY, Hamburg, Germany L. Monaco, D. Sertore INFN/LASA, Segrate (MI), Italy
	The photoinjectors of FLASH and the European XFEL at DESY (Hamburg, Germany) are operated by laser driven RF-guns. In both facilities Cs2Te photocathodes are successfully used. In this paper we give an update on the lifetime, quantum efficiency (QE) and dark current of the photocathodes used over the last years. At FLASH cathode #73.3 was operated for a record lifetime of 1413 days and was replaced December 2018 by cathode #10⁵.2. At the European XFEL cathode #680.1 is in operation since December 2015, for 1356 days up to now.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP047
About •	paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019
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WEP049	RF Power Waveguide Distribution for the RF Gun of the European XFEL at DESY	GUI, FEL, klystron, cryomodule	434
	B. Yildirim, S. Choroba, V.V. Katalev, P. Morozov, Y. Nachtigal DESY, Hamburg, Germany E.M. Apostolov Technical University of Sofia, Sofia, Bulgaria
	The first section of the European XFEL provides the 43 m long injector. The injector consists of a 1.3 GHz RF gun, a 1.3 GHz cryomodule, a 3.9 GHz cryomodule and an extensive diagnostic section. The RF gun operates with a maximum RF peak power up to 6.5 MW, 10 Hz repetition rate and up to 650 µs pulse length. The starting point in the 1.5 cell normal conducting L-Band cavity of the RF gun is a Cs2Te photocathode, which produces electron bunches, which are injected into the superconducting accelerating section of the European XFEL. The RF power is generated by a 10 MW multi beam klystron and distributed to the RF gun through a RF power waveguide distribution system. In order to enhance the reliability of the distribution system, the peak power is minimized in every section of the system by splitting the power in different branches. The RF power reaches its maximum just in front of the RF gun after combination of all branches. An additional air pressure system decreases the break down level in the waveguides of the distribution. We present the layout of the waveguide distribution system for the XFEL RF gun at DESY and report on first operation experience.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP049
About •	paper received ※ 19 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP051	PITZ Experimental Optimization for the Aimed Cathode Gradient of a Superconducting CW RF Gun	emittance, laser, cathode, SRF	440
	M. Krasilnikov, P. Boonpornprasert, Y. Chen, G.Z. Georgiev, J.D. Good, M. Groß, P.W. Huang, I.I. Isaev, C. Koschitzki, S. Lal, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko DESY Zeuthen, Zeuthen, Germany M. Dohlus, E. Vogel DESY, Hamburg, Germany
	A continuous wave (CW) mode operation of the European X-ray Free-Electron Laser (XFEL) is under considerations for a future upgrade. Therefore, a superconducting radio frequency (SRF) CW gun is under experimental development at DESY in Hamburg. Beam dynamics simulations for this setup have been done assuming 100 pC bunch charge and a maximum electric field at the photocathode of 40 MV/m. Experimental studies for these parameters using a normal conducting RF photogun have been performed at the Photo Injector Test facility at DESY in Zeuthen (PITZ). The beam transverse emittance was minimized by optimizing the main photo injector parameters in order to demonstrate the feasibility of generating electron beams with a beam quality required for successful CW operation of the European XFEL for conditions similar to the SRF gun setup.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP051
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP052	Simulation Studies on the Saturated Emission at PITZ	laser, space-charge, simulation, cathode	444
	X. Li, P. Boonpornprasert, Y. Chen, J.D. Good, M. Groß, I.I. Isaev, C. Koschitzki, M. Krasilnikov, S. Lal, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko DESY Zeuthen, Zeuthen, Germany
	In this paper we report our consideration and simulation on the space charge dominated emission in the L-band photocathode RF gun at the Photo Injector Test facility at DESY in Zeuthen (PITZ). It has been found that the emission curve, which relates the extracted and accelerated bunch charge after the gun to the laser energy, doesn’t agree very well with Astra simulations when the emission is nearly or fully saturated. Previous studies with a core-halo model for a better fit of the experimentally measured laser transverse profile as well as with an improved transient emission model have resulted in a better agreement between experimental data and simulation. A 3D FFT space charge solver including mirror charge and binned energy/momentum has been built, which also allows more emission mechanisms to be included in the future. In this paper, the energy spread during emission was preliminarily analyzed. Experimentally measured emission curves were compared with simulation, showing the effect of the inhomogeneity of the laser on the emission and beam parameters.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP052
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP053	Development of a Multialkali Antimonide Photocathode at INFN LASA	cathode, laser, site, electron	448
	S.K. Mohanty DESY Zeuthen, Zeuthen, Germany G. Guerini Rocco, C. Pagani Università degli Studi di Milano & INFN, Segrate, Italy P. Michelato, L. Monaco, D. Sertore INFN/LASA, Segrate (MI), Italy
	Owing to their excellent properties including high quantum efficiency (QE), low emittance, good lifetime and fast response, alkali antimonides photocathodes has been considered as one of the eminent candidates for the electron source of energy recovery linacs (ERL) and free electron lasers (FEL). Nevertheless, their sensitivity to vacuum condition requires specific R&D before they can operate in a RF Gun. For this reason, we have started to develop specifically K-Cs-Sb based multialkali photocathodes at INFN LASA. The primary goal is to develop a stable and reproducible alkali antimonide films on INFN plugs and test them in the photoinjector test facility PITZ at DESY Zeuthen. In this report, we present and discuss about the results so far obtained on KCsSb material and the status of the new preparation system specifically designed for these sensitive materials.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP053
About •	paper received ※ 08 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP054	Beam Dynamics Optimization of a Normal-Conducting Gun Based CW Injector for the European XFEL	cavity, cathode, FEL, cryomodule	452
	H. Shaker, S. Lal, H.J. Qian, G. Shu, F. Stephan DESY Zeuthen, Zeuthen, Germany
	The European XFEL is operating up to 17.5 GeV electron energy with maximum 0.65% duty cycle. There is a prospect for continuous wave and long pulse mode (CW/LP) operation of the European XFEL, which enables more flexible bunch pattern time structure for experiments, higher average brightness and better stability. Due to engineering limitations, the maximum electron beam energy in the CW/LP mode is about 8.6/12.8 GeV, which puts more pressure on the injector beam quality for lasing at the shortest wavelength. This paper optimizes the beam dynamics of an injector based on a normal-conducting VHF gun.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP054
About •	paper received ※ 20 August 2019 paper accepted ※ 26 August 2019 issue date ※ 05 November 2019
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WEP055	Multiphysics Analysis of a CW VHF Gun for European XFEL	cavity, simulation, FEL, vacuum	456
	G. Shu, Y. Chen, S. Lal, H.J. Qian, H. Shaker, F. Stephan DESY Zeuthen, Zeuthen, Germany
	R&D for a possible future CW mode operation of European XFEL started after the successful commissioning of the pulse mode operation. For the CW electron source upgrade, a fully superconducting CW gun is under experimental development at DESY in Hamburg, and a normal conducting (NC) CW gun is under physics design at the Photo Injector Test facility at DESY in Zeuthen (PITZ) as a backup option. Based on the experience of the LBNL on a 187 MHz gun, the DESY 217 MHz gun increased the cathode gradient and RF power to 28 MV/m and 100 kW, respectively, to further improve the beam brightness. In this paper, the multiphysics analysis investigating the RF, thermal and mechanical properties of the 217 MHz NC CW gun are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP055
About •	paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019
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WEP062	Test of Cs2Te Thickness on Cathode Performance at PITZ	cathode, emittance, laser, FEL	473
	P.W. Huang TUB, Beijing, People’s Republic of China Y. Chen, M. Groß, I.I. Isaev, P. Kitisri, C. Koschitzki, M. Krasilnikov, S. Lal, X. Li, O. Lishilin, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko, T. Weilbach DESY Zeuthen, Zeuthen, Germany A. Grigoryan CANDLE, Yerevan, Armenia S. Lederer DESY, Hamburg, Germany P. Michelato, L. Monaco, D. Sertore INFN/LASA, Segrate (MI), Italy
	Cesium telluride is a widely used cathode in photo injectors, and its performance is one of the keys for not only emittance but also reliable operation. Over the years lots of experiences with Cs2Te photocathodes produced with the same recipe and thickness were gained at the DESY photo injectors, but cathode performance dependence on the cathode layer thickness were not investigated. In this paper, we test fresh Cs2Te cathodes with different thickness at the Photo Injector Test Facility at DESY in Zeuthen (PITZ). The QE and thermal emittance of these cathodes inside the high gradient RF gun will be compared. Besides, the injector emittance under the operation conditions of the XFEL will also be measured with these cathodes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP062
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP064	Performance of S-Band Photocathode RF Gun With Coaxial Coupler	electron, laser, FEL, cathode	481
	J.H. Hong, J.H. Han, C.-K. Min PAL, Pohang, Kyungbuk, Republic of Korea
	To improve the characteristics of electron beams, new S-band photocathode RF gun with a coaxial coupler has been developed and fabricated at the Pohang Accelerator Laboratory (PAL). This new RF gun is improved the field symmetry inside the cavity cell by applying the coaxial coupler, and the cooling performance by improving the cooling lines. The RF gun is installed in the injector test facility (ITF) for high power RF test. This paper reports the recent results on the RF conditioning process and the beam tests of the RF gun with high power RF at ITF. We present and discuss the measurement results of the basic beam parameters.
	Poster WEP064 [0.784 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP064
About •	paper received ※ 24 August 2019 paper accepted ※ 26 August 2019 issue date ※ 05 November 2019
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THP007	Frequency-Detuning Dependent Transient Coaxial RF Coupler Kick	cavity, focusing, simulation, electron	599
	Y. Chen, J.D. Good, M. Groß, P.W. Huang, I.I. Isaev, C. Koschitzki, M. Krasilnikov, S. Lal, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko DESY Zeuthen, Zeuthen, Germany F. Brinker, W. Decking DESY, Hamburg, Germany
	We model and characterize a transverse kick which results from the coaxial RF coupler in the L-band RF gun at the Photo Injector Test Facility at DESY in Zeuthen (PITZ). The RF pulse is typically 600 µs long and used to produce a train of up to 2700 electron bunches. The kick is transient and found to be dependent on the detuning of the resonance frequency of the gun cavity. The frequency detuning within the RF macro-pulse results in a variation in the kick strength along the pulse. This leads to a downstream orbit and size change of individual bunches within the train. Using 3D RF field distributions calculated at detuned frequencies of the cavity, particle tracking simulations are performed to simulate the transient kick onto the bunch train. Given a drift distance, the orbit and size change along a train of fixed length is estimated. Systematic measurements of the kick have meanwhile been carried out. The temperature of the cooling water for the gun is tuned allowing detailed characterization of the frequency detuning within the RF pulse, and thereby measurements of the kick under conditions of practical interest. Experimental findings and simulation results will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP007
About •	paper received ※ 13 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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THP027	Simulation and Optimization of the Transport Beamline for the NovoFEL RF Gun	simulation, electron, solenoid, emittance	647
	A.S. Matveev, I.V. Davidyuk, O.A. Shevchenko, V.G. Tcheskidov, N.A. Vinokurov, V. Volkov BINP SB RAS, Novosibirsk, Russia I.V. Davidyuk, A.S. Matveev, N.A. Vinokurov NSU, Novosibirsk, Russia
	A new low-frequency CW RF gun was developed and tested at Budker Institute of Nuclear Physics recently. We plan to use it to upgrade the ERL of the Novosibirsk FEL facility. It will allow increasing the average beam current (due to higher beam repetition rate) and thus increasing the average radiation power. The transport beamline for the RF gun uses the ninety-degree achromatic bend. It is designed in a way that keeps an option to operate with the old electrostatic gun as well. Due to the low beam energy (290 keV) the beam dynamics is strongly influenced by space-charge forces. The paper describes results of simulation and optimization of the RF gun transport beamline. Space-charge forces were taken into account with the code ASTRA. Main sources of emittance degradation were considered in order to decrease their influence during the optimization. In addition, the RF gun output beam parameters were measured for various RF gun emission phases. These experiments were simulated and the results were compared. The resulting beam parameters meets requirements of the Novosibirsk FEL facility ERL.
	Poster THP027 [3.158 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP027
About •	paper received ※ 16 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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THP031	Simulation and Optimization of Injector System for the Pre-bunched THz FEL	electron, linac, radiation, simulation	654
	N. Chaisueb, S. Rimjaem Chiang Mai University, Chiang Mai, Thailand S. Rimjaem ThEP Center, Commission on Higher Education, Bangkok, Thailand
	A linac-based light source for generation of infrared free-electron laser is under the development at Chiang Mai University, Thailand. The injector system of the facility consists mainly of an S-band thermionic cathode RF electron gun, a pre-bunch compressor in a form of an alpha magnet and a travelling-wave linac structure. Two 180-degree magnetic bunch compressors are installed downstream the injector system. Two separate radiation beamlines for mid-infrared (MIR) and terahertz (THz) free-electron laser (FEL) are located following the bunch compressor systems. In this contribution, we focus only on the coherent and high-power pre-bunch THz FEL that is generated from electron bunches with a femtosecond length. Electron beam dynamic simulations with program ASTRA were performed to obtain optimal electron beam properties. Optimization of the injector system for the THz FEL is thus presented. The simulated results show that the beam at the linac exit has a bunch length of 282 fs with a charge of 200 pC when the linac RF phase is 90° and the alpha gradient is 300 G/cm. This optimal condition will be used as an input for simulation in the 180-degree bunch compressor system and in the THz undulator magnet.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP031
About •	paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019
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THP078	Status of the CompactLight Design Study	FEL, linac, electron, undulator	738
	G. D’Auria, S. Di Mitri, R.A. Rochow Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy M. Aicheler HIP, University of Helsinki, Finland A. Aksoy Ankara University Institute of Accelerator Technologies, Golbasi, Turkey D. Alesini, M. Bellaveglia, B. Buonomo, F. Cardelli, M. Croia, M. Diomede, M. Ferrario, A. Gallo, A. Giribono, L. Piersanti, J. Scifo, B. Spataro, C. Vaccarezza INFN/LNF, Frascati, Italy R. Apsimon, G. Burt, A. Castilla Cockcroft Institute, Lancaster University, Lancaster, United Kingdom J.M. Arnesano, F. Bosco, L. Ficcadenti, A. Mostacci, L. Palumbo Sapienza University of Rome, Rome, Italy A. Bernhard, J. Gethmann KIT, Karlsruhe, Germany M. Calvi, T. Schmidt, K. Zhang PSI, Villigen PSI, Switzerland H.M. Castañeda Cortés, J.A. Clarke, D.J. Dunning, N. Thompson STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom A.W. Cross, L. Zhang USTRAT/SUPA, Glasgow, United Kingdom G. Dattoli, F. Nguyen, A. Petralia ENEA C.R. Frascati, Frascati (Roma), Italy R.T. Dowd, D. Zhu AS - ANSTO, Clayton, Australia D. Esperante Pereira, J. Fuster, D. Gonzalez-Iglesias IFIC, Valencia, Spain W. Fang SINAP, Shanghai, People’s Republic of China A. Faus-Golfe, Y. Han LAL, Orsay, France E.N. Gazis, N. Gazis National Technical University of Athens, Athens, Greece R. Geometrante, M. Kokole KYMA, Trieste, Italy B. Gimeno UVEG, Burjasot (Valencia), Spain V.A. Goryashko, M. Jacewicz, R.J.M.Y. Ruber Uppsala University, Uppsala, Sweden R. Hoekstra ARCNL, Amsterdam, The Netherlands X.J.A. Janssen, J.M.A. Priem VDL ETG, Eindhoven, The Netherlands A. Latina, X. Liu, C. Rossi, D. Schulte, S. Stapnes, X.W. Wu, W. Wuensch CERN, Geneva, Switzerland O.J. Luiten, P.H.A. Mutsaers, X.F.D. Stragier TUE, Eindhoven, The Netherlands J. Marcos, E. Marín, R. Muñoz Horta, F. Pérez ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain Z. Nergiz Ankara University, Faculty of Sciences, Ankara, Turkey L.J.R. Nix University of Strathclyde, Glasgow, United Kingdom E. Tanke, E. Trachnas ESS, Lund, Sweden G. Taylor The University of Melbourne, Melbourne, Victoria, Australia
	Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 777431. CompactLight (XLS) is an International Collaboration of 24 partners and 5 third parties, funded by the European Union through the Horizon 2020 Research and Innovation Programme. The main goal of the project, which started in January 2018 with a duration of 36 months, is the design of an hard X-ray FEL facility beyond today’s state of the art, using the latest concepts for bright electron photo-injectors, high-gradient accelerating structures, and innovative short-period undulators. The specifications of the facility and the parameters of the future FEL are driven by the demands of potential users and the associated science cases. In this paper we will give an overview on the ongoing activities and the major results achieved until now.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP078
About •	paper received ※ 19 August 2019 paper accepted ※ 29 August 2019 issue date ※ 05 November 2019
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Paper

Title

Other Keywords

Page

TUP012

Smith-Purcell Radiation Emitted by Pico-second Electron Bunches from a 30 keV Photo-Electron Gun

electron, radiation, experiment, laser

66

M.R. Asakawa, S. Yamaguchi
Kansai University, Osaka, Japan

In this paper, an experiment to generate Smith-Purcell radiation using pico-second electron bunches is reported. The electron bunch was produced by a DC 30 keV photo-electron electron gun driven by a 100 fs Ti:sapphire laser. The charge of the bunch varied from 1 pC to 300 pC by changing the laser power. Smith-Purcell radiation experiment was performed with the central part of the entire electron bunch. Estimation of pulsewidth of the bunch based on the envelope equation showed that the pulsewidth of the bunch at the anode electrode increased from 0.8 ps to 3.2 ps as the bunch charge increase from 0.1 pC to 11 pC. Such electron bunch was traveled along the surface of the metallic grating with a period of 2 mm. The radiation wavelength was estimated to be 4 mm at an obserbation angle of 10 degree. The radiation power was measured by a bolometer and quadraticallly increased with the bunch charge. Numerical simulation of this experiment indicated the enhancement of the harmonic components of the radiation. We are now constructing a THz-TDS system to measure the time-trace of the electric field of the radiation.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-TUP012

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paper received ※ 14 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEA01

Overview of CW RF Guns for Short Wavelength FELs

cathode, FEL, SRF, electron

290

H.J. Qian
DESY Zeuthen, Zeuthen, Germany
E. Vogel
DESY, Hamburg, Germany

Hard X-ray FELs (XFELs) operating with pulsed RF provide unprecedented peak brilliance for scientific research. Operating the accelerators with CW RF improves the flexibility w.r.t. the available time structure for experiments and opens the next frontier of average brilliance. One of the challenges of CW XFELs is the electron source, which requires both CW operation and highest possible beam quality allowing lasing at shortest wavelengths. The CW mode technically constraints the gun acceleration gradient, which is one of the keys to electron source brightness, so R&D is devoted to CW gun improvements since decades. In this contribution, the worldwide development status of CW RF guns, both normal conducting and superconducting, is reviewed.

Slides WEA01 [16.329 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEA01

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paper received ※ 25 August 2019 paper accepted ※ 07 November 2019 issue date ※ 05 November 2019

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WEA04

Growing and Characterization of Cs2Te Photocatodes with Different Thicknesses at INFN LASA

cathode, electron, diagnostics, FEL

297

L. Monaco, P. Michelato, D. Sertore
INFN/LASA, Segrate (MI), Italy
G. Guerini Rocco, C. Pagani
Università degli Studi di Milano & INFN, Segrate, Italy

The INFN LASA group has a long standing experience in the production of cesium telluride photocathodes for high brightness photoinjectors. The well-established recipe relies on the deposition of a typical amount of 10 nm of Te, followed by the Cs deposition until reaching the maximum QE. Nevertheless, for improving the understanding of photocathode properties, we are investigating the effect of Te thickness on the growing process, evaluating photocathode optical properties and quantum efficiency during the growing process and on the final film. These photocathodes will be then operated and analyzed in the real environment of the RF Gun at the PITZ facility in DESY Zeuthen, to estimate their impact on the electron beam properties.

Slides WEA04 [15.703 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEA04

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paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP026

Preliminary Geometry Optimization of a 3.5-Cell SRF Gun Cavity at ELBE Based on Beam Dynamics

SRF, cavity, emittance, electron

374

K. Zhou, P. Li
CAEP/IAE, Mianyang, Sichuan, People’s Republic of China
A. Arnold, S. Ma, J. Schaber, J. Teichert, R. Xiang
HZDR, Dresden, Germany

At present, ELBE radiation source at HZDR is optimizing the SRF cavity for the next generation ELBE SRF GUN. This paper presents a preliminary study on the geometry optimization of a 3.5-cell SRF gun cavity based on beam dynamics. By changing the lengths of the half cell and the first TESLA like cell, two new cavity models with higher electric field in the half cell are built and their RF fields are compared with SRF GUN I and SRF GUN II. Through the scanning of the RF phases and the electric fields, the simulation results indicate that new models have smaller transverse emittance at relatively lower electric field gradients and better performance on longitudinal emittance than SRF GUN I and SRF GUN II.

Poster WEP026 [1.345 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP026

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paper received ※ 19 August 2019 paper accepted ※ 29 August 2019 issue date ※ 05 November 2019

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WEP031

Timing Synchronization Activities for Drift-Free Operation of Ultrafast Electron Diffraction System at KAERI

electron, timing, laser, detector

385

J. Shin, J. Kim
KAIST, Daejeon, Republic of Korea
I.H. Baek, Y.U. Jeong, H.W. Kim, K. Oang, S. Park
KAERI, Daejon, Republic of Korea

Funding: This work is funded by KAERI (Grant number: 525350-19)
Precise timing synchronization of an ultrafast electron diffraction facility is essential requirement for femtosecond resolution structure analysis. Recent studies of THz-based electron deflectors have enabled the timing drift measurement between ultrafast electrons and an optical pump beam with few femtosecond resolution [1]. In this work, we will introduce timing synchronization activities to suppress the drift of an electron beam. As timing drift of the electron beam originates from every sub-element, each timing drift contribution from RF transfer, RF-to-optical synchronization, and optical amplification is measured. Timing drift of RF transfer through coaxial cable, which exposed to temperature fluctuation, is actively stabilized from 2 ps to 50 fs by active feedback loop. Further additive drift from RF-to-optical synchronization is maintained below 100 fs. Also optical drift due to the regenerative amplifier, measured by optical correlator, is maintained below 20 fs over an hour. This work allows ultrafast electron diffraction system to operate with less drift correction procedure and increased user availability.
[1] H. Yang et al., "10-fs-level synchronization of photocathode laser with RF-oscillator for ultrafast electron and X-ray sources", Sci. Rep. 7, 39966 (2017).

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP031

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paper received ※ 24 August 2019 paper accepted ※ 25 August 2019 issue date ※ 05 November 2019

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WEP047

Update on the Photocathode Lifetime at FLASH and European XFEL

cathode, FEL, laser, operation

427

S. Lederer, F. Brinker, S. Schreiber
DESY, Hamburg, Germany
L. Monaco, D. Sertore
INFN/LASA, Segrate (MI), Italy

The photoinjectors of FLASH and the European XFEL at DESY (Hamburg, Germany) are operated by laser driven RF-guns. In both facilities Cs2Te photocathodes are successfully used. In this paper we give an update on the lifetime, quantum efficiency (QE) and dark current of the photocathodes used over the last years. At FLASH cathode #73.3 was operated for a record lifetime of 1413 days and was replaced December 2018 by cathode #10⁵.2. At the European XFEL cathode #680.1 is in operation since December 2015, for 1356 days up to now.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP047

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paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019

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WEP049

RF Power Waveguide Distribution for the RF Gun of the European XFEL at DESY

GUI, FEL, klystron, cryomodule

434

B. Yildirim, S. Choroba, V.V. Katalev, P. Morozov, Y. Nachtigal
DESY, Hamburg, Germany
E.M. Apostolov
Technical University of Sofia, Sofia, Bulgaria

The first section of the European XFEL provides the 43 m long injector. The injector consists of a 1.3 GHz RF gun, a 1.3 GHz cryomodule, a 3.9 GHz cryomodule and an extensive diagnostic section. The RF gun operates with a maximum RF peak power up to 6.5 MW, 10 Hz repetition rate and up to 650 µs pulse length. The starting point in the 1.5 cell normal conducting L-Band cavity of the RF gun is a Cs2Te photocathode, which produces electron bunches, which are injected into the superconducting accelerating section of the European XFEL. The RF power is generated by a 10 MW multi beam klystron and distributed to the RF gun through a RF power waveguide distribution system. In order to enhance the reliability of the distribution system, the peak power is minimized in every section of the system by splitting the power in different branches. The RF power reaches its maximum just in front of the RF gun after combination of all branches. An additional air pressure system decreases the break down level in the waveguides of the distribution. We present the layout of the waveguide distribution system for the XFEL RF gun at DESY and report on first operation experience.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP049

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paper received ※ 19 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP051

PITZ Experimental Optimization for the Aimed Cathode Gradient of a Superconducting CW RF Gun

emittance, laser, cathode, SRF

440

M. Krasilnikov, P. Boonpornprasert, Y. Chen, G.Z. Georgiev, J.D. Good, M. Groß, P.W. Huang, I.I. Isaev, C. Koschitzki, S. Lal, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko
DESY Zeuthen, Zeuthen, Germany
M. Dohlus, E. Vogel
DESY, Hamburg, Germany

A continuous wave (CW) mode operation of the European X-ray Free-Electron Laser (XFEL) is under considerations for a future upgrade. Therefore, a superconducting radio frequency (SRF) CW gun is under experimental development at DESY in Hamburg. Beam dynamics simulations for this setup have been done assuming 100 pC bunch charge and a maximum electric field at the photocathode of 40 MV/m. Experimental studies for these parameters using a normal conducting RF photogun have been performed at the Photo Injector Test facility at DESY in Zeuthen (PITZ). The beam transverse emittance was minimized by optimizing the main photo injector parameters in order to demonstrate the feasibility of generating electron beams with a beam quality required for successful CW operation of the European XFEL for conditions similar to the SRF gun setup.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP051

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paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP052

Simulation Studies on the Saturated Emission at PITZ

laser, space-charge, simulation, cathode

444

X. Li, P. Boonpornprasert, Y. Chen, J.D. Good, M. Groß, I.I. Isaev, C. Koschitzki, M. Krasilnikov, S. Lal, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko
DESY Zeuthen, Zeuthen, Germany

In this paper we report our consideration and simulation on the space charge dominated emission in the L-band photocathode RF gun at the Photo Injector Test facility at DESY in Zeuthen (PITZ). It has been found that the emission curve, which relates the extracted and accelerated bunch charge after the gun to the laser energy, doesn’t agree very well with Astra simulations when the emission is nearly or fully saturated. Previous studies with a core-halo model for a better fit of the experimentally measured laser transverse profile as well as with an improved transient emission model have resulted in a better agreement between experimental data and simulation. A 3D FFT space charge solver including mirror charge and binned energy/momentum has been built, which also allows more emission mechanisms to be included in the future. In this paper, the energy spread during emission was preliminarily analyzed. Experimentally measured emission curves were compared with simulation, showing the effect of the inhomogeneity of the laser on the emission and beam parameters.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP052

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paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP053

Development of a Multialkali Antimonide Photocathode at INFN LASA

cathode, laser, site, electron

448

S.K. Mohanty
DESY Zeuthen, Zeuthen, Germany
G. Guerini Rocco, C. Pagani
Università degli Studi di Milano & INFN, Segrate, Italy
P. Michelato, L. Monaco, D. Sertore
INFN/LASA, Segrate (MI), Italy

Owing to their excellent properties including high quantum efficiency (QE), low emittance, good lifetime and fast response, alkali antimonides photocathodes has been considered as one of the eminent candidates for the electron source of energy recovery linacs (ERL) and free electron lasers (FEL). Nevertheless, their sensitivity to vacuum condition requires specific R&D before they can operate in a RF Gun. For this reason, we have started to develop specifically K-Cs-Sb based multialkali photocathodes at INFN LASA. The primary goal is to develop a stable and reproducible alkali antimonide films on INFN plugs and test them in the photoinjector test facility PITZ at DESY Zeuthen. In this report, we present and discuss about the results so far obtained on KCsSb material and the status of the new preparation system specifically designed for these sensitive materials.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP053

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paper received ※ 08 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP054

Beam Dynamics Optimization of a Normal-Conducting Gun Based CW Injector for the European XFEL

cavity, cathode, FEL, cryomodule

452

H. Shaker, S. Lal, H.J. Qian, G. Shu, F. Stephan
DESY Zeuthen, Zeuthen, Germany

The European XFEL is operating up to 17.5 GeV electron energy with maximum 0.65% duty cycle. There is a prospect for continuous wave and long pulse mode (CW/LP) operation of the European XFEL, which enables more flexible bunch pattern time structure for experiments, higher average brightness and better stability. Due to engineering limitations, the maximum electron beam energy in the CW/LP mode is about 8.6/12.8 GeV, which puts more pressure on the injector beam quality for lasing at the shortest wavelength. This paper optimizes the beam dynamics of an injector based on a normal-conducting VHF gun.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP054

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paper received ※ 20 August 2019 paper accepted ※ 26 August 2019 issue date ※ 05 November 2019

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WEP055

Multiphysics Analysis of a CW VHF Gun for European XFEL

cavity, simulation, FEL, vacuum

456

G. Shu, Y. Chen, S. Lal, H.J. Qian, H. Shaker, F. Stephan
DESY Zeuthen, Zeuthen, Germany

R&D for a possible future CW mode operation of European XFEL started after the successful commissioning of the pulse mode operation. For the CW electron source upgrade, a fully superconducting CW gun is under experimental development at DESY in Hamburg, and a normal conducting (NC) CW gun is under physics design at the Photo Injector Test facility at DESY in Zeuthen (PITZ) as a backup option. Based on the experience of the LBNL on a 187 MHz gun, the DESY 217 MHz gun increased the cathode gradient and RF power to 28 MV/m and 100 kW, respectively, to further improve the beam brightness. In this paper, the multiphysics analysis investigating the RF, thermal and mechanical properties of the 217 MHz NC CW gun are presented.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP055

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paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019

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WEP062

Test of Cs2Te Thickness on Cathode Performance at PITZ

cathode, emittance, laser, FEL

473

P.W. Huang
TUB, Beijing, People’s Republic of China
Y. Chen, M. Groß, I.I. Isaev, P. Kitisri, C. Koschitzki, M. Krasilnikov, S. Lal, X. Li, O. Lishilin, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko, T. Weilbach
DESY Zeuthen, Zeuthen, Germany
A. Grigoryan
CANDLE, Yerevan, Armenia
S. Lederer
DESY, Hamburg, Germany
P. Michelato, L. Monaco, D. Sertore
INFN/LASA, Segrate (MI), Italy

Cesium telluride is a widely used cathode in photo injectors, and its performance is one of the keys for not only emittance but also reliable operation. Over the years lots of experiences with Cs2Te photocathodes produced with the same recipe and thickness were gained at the DESY photo injectors, but cathode performance dependence on the cathode layer thickness were not investigated. In this paper, we test fresh Cs2Te cathodes with different thickness at the Photo Injector Test Facility at DESY in Zeuthen (PITZ). The QE and thermal emittance of these cathodes inside the high gradient RF gun will be compared. Besides, the injector emittance under the operation conditions of the XFEL will also be measured with these cathodes.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP062

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paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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WEP064

Performance of S-Band Photocathode RF Gun With Coaxial Coupler

electron, laser, FEL, cathode

481

J.H. Hong, J.H. Han, C.-K. Min
PAL, Pohang, Kyungbuk, Republic of Korea

To improve the characteristics of electron beams, new S-band photocathode RF gun with a coaxial coupler has been developed and fabricated at the Pohang Accelerator Laboratory (PAL). This new RF gun is improved the field symmetry inside the cavity cell by applying the coaxial coupler, and the cooling performance by improving the cooling lines. The RF gun is installed in the injector test facility (ITF) for high power RF test. This paper reports the recent results on the RF conditioning process and the beam tests of the RF gun with high power RF at ITF. We present and discuss the measurement results of the basic beam parameters.

Poster WEP064 [0.784 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP064

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paper received ※ 24 August 2019 paper accepted ※ 26 August 2019 issue date ※ 05 November 2019

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THP007

Frequency-Detuning Dependent Transient Coaxial RF Coupler Kick

cavity, focusing, simulation, electron

599

Y. Chen, J.D. Good, M. Groß, P.W. Huang, I.I. Isaev, C. Koschitzki, M. Krasilnikov, S. Lal, X. Li, O. Lishilin, G. Loisch, D. Melkumyan, R. Niemczyk, A. Oppelt, H.J. Qian, H. Shaker, G. Shu, F. Stephan, G. Vashchenko
DESY Zeuthen, Zeuthen, Germany
F. Brinker, W. Decking
DESY, Hamburg, Germany

We model and characterize a transverse kick which results from the coaxial RF coupler in the L-band RF gun at the Photo Injector Test Facility at DESY in Zeuthen (PITZ). The RF pulse is typically 600 µs long and used to produce a train of up to 2700 electron bunches. The kick is transient and found to be dependent on the detuning of the resonance frequency of the gun cavity. The frequency detuning within the RF macro-pulse results in a variation in the kick strength along the pulse. This leads to a downstream orbit and size change of individual bunches within the train. Using 3D RF field distributions calculated at detuned frequencies of the cavity, particle tracking simulations are performed to simulate the transient kick onto the bunch train. Given a drift distance, the orbit and size change along a train of fixed length is estimated. Systematic measurements of the kick have meanwhile been carried out. The temperature of the cooling water for the gun is tuned allowing detailed characterization of the frequency detuning within the RF pulse, and thereby measurements of the kick under conditions of practical interest. Experimental findings and simulation results will be presented.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP007

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paper received ※ 13 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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THP027

Simulation and Optimization of the Transport Beamline for the NovoFEL RF Gun

simulation, electron, solenoid, emittance

647

A.S. Matveev, I.V. Davidyuk, O.A. Shevchenko, V.G. Tcheskidov, N.A. Vinokurov, V. Volkov
BINP SB RAS, Novosibirsk, Russia
I.V. Davidyuk, A.S. Matveev, N.A. Vinokurov
NSU, Novosibirsk, Russia

A new low-frequency CW RF gun was developed and tested at Budker Institute of Nuclear Physics recently. We plan to use it to upgrade the ERL of the Novosibirsk FEL facility. It will allow increasing the average beam current (due to higher beam repetition rate) and thus increasing the average radiation power. The transport beamline for the RF gun uses the ninety-degree achromatic bend. It is designed in a way that keeps an option to operate with the old electrostatic gun as well. Due to the low beam energy (290 keV) the beam dynamics is strongly influenced by space-charge forces. The paper describes results of simulation and optimization of the RF gun transport beamline. Space-charge forces were taken into account with the code ASTRA. Main sources of emittance degradation were considered in order to decrease their influence during the optimization. In addition, the RF gun output beam parameters were measured for various RF gun emission phases. These experiments were simulated and the results were compared. The resulting beam parameters meets requirements of the Novosibirsk FEL facility ERL.

Poster THP027 [3.158 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP027

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paper received ※ 16 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

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THP031

Simulation and Optimization of Injector System for the Pre-bunched THz FEL

electron, linac, radiation, simulation

654

N. Chaisueb, S. Rimjaem
Chiang Mai University, Chiang Mai, Thailand
S. Rimjaem
ThEP Center, Commission on Higher Education, Bangkok, Thailand

A linac-based light source for generation of infrared free-electron laser is under the development at Chiang Mai University, Thailand. The injector system of the facility consists mainly of an S-band thermionic cathode RF electron gun, a pre-bunch compressor in a form of an alpha magnet and a travelling-wave linac structure. Two 180-degree magnetic bunch compressors are installed downstream the injector system. Two separate radiation beamlines for mid-infrared (MIR) and terahertz (THz) free-electron laser (FEL) are located following the bunch compressor systems. In this contribution, we focus only on the coherent and high-power pre-bunch THz FEL that is generated from electron bunches with a femtosecond length. Electron beam dynamic simulations with program ASTRA were performed to obtain optimal electron beam properties. Optimization of the injector system for the THz FEL is thus presented. The simulated results show that the beam at the linac exit has a bunch length of 282 fs with a charge of 200 pC when the linac RF phase is 90° and the alpha gradient is 300 G/cm. This optimal condition will be used as an input for simulation in the 180-degree bunch compressor system and in the THz undulator magnet.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP031

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paper received ※ 20 August 2019 paper accepted ※ 28 August 2019 issue date ※ 05 November 2019

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THP078

Status of the CompactLight Design Study

FEL, linac, electron, undulator

738

G. D’Auria, S. Di Mitri, R.A. Rochow
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
M. Aicheler
HIP, University of Helsinki, Finland
A. Aksoy
Ankara University Institute of Accelerator Technologies, Golbasi, Turkey
D. Alesini, M. Bellaveglia, B. Buonomo, F. Cardelli, M. Croia, M. Diomede, M. Ferrario, A. Gallo, A. Giribono, L. Piersanti, J. Scifo, B. Spataro, C. Vaccarezza
INFN/LNF, Frascati, Italy
R. Apsimon, G. Burt, A. Castilla
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
J.M. Arnesano, F. Bosco, L. Ficcadenti, A. Mostacci, L. Palumbo
Sapienza University of Rome, Rome, Italy
A. Bernhard, J. Gethmann
KIT, Karlsruhe, Germany
M. Calvi, T. Schmidt, K. Zhang
PSI, Villigen PSI, Switzerland
H.M. Castañeda Cortés, J.A. Clarke, D.J. Dunning, N. Thompson
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
A.W. Cross, L. Zhang
USTRAT/SUPA, Glasgow, United Kingdom
G. Dattoli, F. Nguyen, A. Petralia
ENEA C.R. Frascati, Frascati (Roma), Italy
R.T. Dowd, D. Zhu
AS - ANSTO, Clayton, Australia
D. Esperante Pereira, J. Fuster, D. Gonzalez-Iglesias
IFIC, Valencia, Spain
W. Fang
SINAP, Shanghai, People’s Republic of China
A. Faus-Golfe, Y. Han
LAL, Orsay, France
E.N. Gazis, N. Gazis
National Technical University of Athens, Athens, Greece
R. Geometrante, M. Kokole
KYMA, Trieste, Italy
B. Gimeno
UVEG, Burjasot (Valencia), Spain
V.A. Goryashko, M. Jacewicz, R.J.M.Y. Ruber
Uppsala University, Uppsala, Sweden
R. Hoekstra
ARCNL, Amsterdam, The Netherlands
X.J.A. Janssen, J.M.A. Priem
VDL ETG, Eindhoven, The Netherlands
A. Latina, X. Liu, C. Rossi, D. Schulte, S. Stapnes, X.W. Wu, W. Wuensch
CERN, Geneva, Switzerland
O.J. Luiten, P.H.A. Mutsaers, X.F.D. Stragier
TUE, Eindhoven, The Netherlands
J. Marcos, E. Marín, R. Muñoz Horta, F. Pérez
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
Z. Nergiz
Ankara University, Faculty of Sciences, Ankara, Turkey
L.J.R. Nix
University of Strathclyde, Glasgow, United Kingdom
E. Tanke, E. Trachnas
ESS, Lund, Sweden
G. Taylor
The University of Melbourne, Melbourne, Victoria, Australia

Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 777431.
CompactLight (XLS) is an International Collaboration of 24 partners and 5 third parties, funded by the European Union through the Horizon 2020 Research and Innovation Programme. The main goal of the project, which started in January 2018 with a duration of 36 months, is the design of an hard X-ray FEL facility beyond today’s state of the art, using the latest concepts for bright electron photo-injectors, high-gradient accelerating structures, and innovative short-period undulators. The specifications of the facility and the parameters of the future FEL are driven by the demands of potential users and the associated science cases. In this paper we will give an overview on the ongoing activities and the major results achieved until now.

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reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP078

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paper received ※ 19 August 2019 paper accepted ※ 29 August 2019 issue date ※ 05 November 2019

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