IPAC2018 - List of Keywords (free-electron-laser)

Paper	Title	Other Keywords	Page
TUPMF044	First Lasing of the CAEP THz FEL Facility Driven by a Superconducting Accelerator	FEL, laser, electron, undulator	1349
	D. Wu, W. Bai, D.R. Deng, C.L. Lao, M. Li, S.F. Lin, X. Luo, L.J. Shan, X. Shen, H. Wang, J. Wang, Y. Xu, L.G. Yan, X. Yang, K. Zhou CAEP/IAE, Mianyang, Sichuan, People's Republic of China Y.H. Dou, X.J. Shu Institute of Applied Physics and Computational Mathematics, People's Republic of China W.-H. Huang TUB, Beijing, People's Republic of China X.Y. Lu PKU, Beijing, People's Republic of China
	Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190) The stimulated saturation of the terahertz free electron laser at China Academy of Engineering Physics 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 wave 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 0.3 MW.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF044
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TUPMF045	Performance Optimization of a Prototype Undulator U38 Using Multi-Objective Genetic Algorithm	undulator, MMI, electron, laser	1353
	L.G. Yan, D.R. Deng, P. Li, D. Wu CAEP/IAE, Mianyang, Sichuan, People's Republic of China
	Funding: The project of the national large-scale instrument development: 2011YQ130018; National Natural Science Foundation of China: 11505174, 11505173 and 11605190. Genetic Algorithm (GA) is one of the most excellent method to search the optimal solution of a problem, which has been applied to solve various problems. It is hard to estimate shim applied on raw undulator precisely. There are many methods have been developed to solve the problem. In this proceeding, we measured the magnetic field distribution of prototype undulator U38 and concluded the shim using multi-objective GA. The code was written with the language of Python and based on the package pyevolve. A multi-objective fitness function was setup to implement the multi-objective optimization. Experimentally，performances satisfied the requirements by shimming U38 three times. The trajectory center deviation, peak-to-peak error and phase error are reduced to 0.15 mm, 0.49% and 1°.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF045
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TUPMF081	Microphonic Detuning Induced Coupler Kick Variation at LCLS-II	cavity, linac, laser, beam-loading	1456
	T. Hellert DESY, Hamburg, Germany W. Ackermann, H. De Gersem TEMF, TU Darmstadt, Darmstadt, Germany C. Adolphsen, Z. Li, C.E. Mayes SLAC, Menlo Park, California, USA
	The LCLS-II free-electron laser will be an upgrade of the existing Linac Coherent Light Source (LCLS), including a 4 GeV CW superconducting linac based on the TESLA technology. The high quality factor of the cavity makes it very sensitive to vibrations. The shift of its eigenfrequency (i.e., detuning) will be compensated by the power source in order to assure a constant accelerating voltage. Significant variations of the forward power are expected which result in coupler kick variations induced by the fundamental power coupler. In this work we estimate the magnitude of trajectory jitter caused by these variations. High precision 3D field maps including standing and traveling-wave components for a cavity with the LCLS-II coupler design are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF081
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THPMK026	Mobile Free-Electron Laser for Remote Atmospheric Survey	laser, FEL, electron, survey	4351
	S. Johnson, G.A. Krafft, B. Terzić ODU, Norfolk, Virginia, USA G.A. Krafft JLab, Newport News, Virginia, USA
	Funding: This paper is authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05- 06OR23177. E.J. was supported by the Virginia Space Grant Consortium, grant number 16-589. Reliable atmospheric surveys for carbon distributions will be essential to building an understanding of the Earth's carbon cycle and the role it plays in climate change. One of the core needs of NASA 's Active Sensing of CO2 Over Nights, Days and Seasons (ASCENDS) Mission is to advance the range and precision of current remote atmospheric survey techniques. The feasibility of using accelerator-based sources of infrared light to improve current airborne lidar systems has been explored. A literary review has been conducted to asses the needs of ASCENDS versus the current capabilities of modern atmospheric survey technology, and the parameters of a free electron laser (FEL) source were calculated for a lidar system that will meet these needs. By using the "Next Linear Collider" from the Stanford Linear Accelerator Center (SLAC), a mobile FEL-based lidar may be constructed for airborne surveillance. The calculated energy of the lidar pulse is 0.1 joule: this output is a two orders of magnitude gain over current lidar systems, so in principle, the mobile FEL will exceed the needs of ASCENDS. Further research will be required to asses other challenges to mobilizing the FEL technology.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK026
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THPMK028	Inverse Free Electron Laser Separatrix Crossing for Energy Gain and Stability	FEL, laser, undulator, electron	4354
	N.S. Sudar, P. Musumeci UCLA, Los Angeles, USA D. Garzella CEA, Gif-sur-Yvette, France
	The laser wakefield accelerator (LWFA) has been proposed as a driver for next generation compact light sources. However, the beams produced by LWFA's typically exhibit correlated energy spread and energy jitter too large to drive the Free Electron Laser instability. We present here a novel scheme whereby using a highly non-linear strongly tapered undulator interaction directly after the LWFA we are able to trap and accelerate a large fraction of charge in the moving Inverse Free Electron Laser ponderomotive bucket. The final correlated energy spread and output energy are determined by the final bucket height and central energy of the ponderomotive bucket which are both determined by the stagnant undulator parameters, resulting in a significant decrease in the normalized energy spread (< 1%) and output energy jitter (< 1%). This interaction is treated both analytically and numerically.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK028
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THPMK045	Generation of High Power, High Intensity, Ultra Short X-Ray FEL Pulses	electron, laser, photon, emittance	4384
	M.W. Guetg, Y. Ding, Z. Huang, A.A. Lutman SLAC, Menlo Park, California, USA
	X-ray Free Electron Lasers combine high pulse power, short pulse length, narrow bandwidth and a high degree of transverse coherence. Any increase in the photon pulse power, while shortening the pulse length, will further push the frontier on several key XFEL applications including single molecule imaging and novel nonlinear X-ray methods. We will present experimental results at the Linac Coherent Light Source raising its maximum power to more than 300% of the current limit, while reducing the photon pulse length to 10 fs. This was achieved by minimizing residual transverse-longitudinal centroid beam offsets and beam yaw, and by correcting the dispersion when operating over 6 kA peak current with a longitudinally shaped beam.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK045
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THPMK046	Advanced Fresh-Slice Beam Manipulations for FEL X-Ray Applications	electron, laser, undulator, controls	4387
	A.A. Lutman, Y. Ding, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell SLAC, Menlo Park, California, USA C. Emma UCLA, Los Angeles, USA
	The recent development of the Fresh-slice technique granted control on which temporal slice lases in each undulator section in an X-ray Free-electron laser. Fresh-slice has been used for several experiments at the Linac Coherent Light Source for the generation of customizable high power two-color beams, and increased the performance of self-seeding schemes. As a novel development of the technique we present the demonstration of multistage self-amplified spontaneous-emission amplification schemes for the production of high-power ultra short pulses and improved control of the temporal duration of each pulse in multi-pulse schemes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK046
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THPMK061	Isolated Few-Cycle Pulse Generation in X-Ray Free-Electron Lasers	electron, bunching, FEL, laser	4434
	D.J. Dunning, L.T. Campbell, N. Thompson STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom L.T. Campbell, B.W.J. MᶜNeil USTRAT/SUPA, Glasgow, United Kingdom D.J. Dunning, B.W.J. MᶜNeil, N. Thompson Cockcroft Institute, Warrington, Cheshire, United Kingdom J.D.A. Smith TXUK, Warrington, United Kingdom
	X-ray free-electron lasers are promising candidates to deliver high-brightness radiation pulses with duration significantly shorter than the present leading technique, high harmonic generation (HHG). This would extend attosecond science to probe ultrafast dynamics with even finer resolution. To do so requires breaking below a characteristic FEL timescale of typically a few hundred optical cycles, dictated by the relative slippage of the radiation and electrons during amplification. The concept of mode-locking enables this, with the mode-locked afterburner configuration predicted to deliver few-cycle pulses (~ 1 attosecond at hard X-ray). However such techniques would produce a train of closely separated pulses, while an isolated pulse would be preferable for some types of experiment. Building on previous techniques, a new concept has been developed for isolated few-cycle pulse generation and it is presented alongside simulation studies.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK061
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THPMK072	X-Band RF System as Linearizer for SXFEL	FEL, laser, electron, cavity	4467
	J.H. Tan, W. Fang, Q. Gu, X.X. Huang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	High gradient accelerating structure is the core technology of compact linear collider facilities and compact free electron laser facilities. Meanwhile the important limitation of improving brightness in free electron laser facility is the non-linear energy spread, and the X-band accelerating structure can provide harmonic compensation in linac to linearize the bunch compression process. In this paper, a special X-band traveling-wave accelerating structure is primary designed for compact hard x-ray free electron laser facility. Then the structure is processed manufacturing, and realize high power experiment and linear bunch compression at Shanghai soft x-ray free electron laser facility.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK072
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THPMK083	Self-Modulation of a Relativistic Electron Beam in a Wiggler	electron, wiggler, laser, radiation	4492
	J.P. MacArthur Stanford University, Stanford, California, USA J.P. Duris, Z. Huang, A. Marinelli, Z. Zhang SLAC, Menlo Park, California, USA
	Users at x-ray free-electron laser (FEL) facilities have shown strong interest in using single spike, coherent x-ray pulses to probe attosceond dynamics in atoms and molecules. Sub-femtosecond soft x-ray pulses may be obtained from an electron beam that has been modulated in a wiggler resonant with an external laser, the enhanced-SASE technique. We discuss a new way to produce this energy modulation, wherein the external laser is replaced by coherent radiation from the current spike on the tail of the electron beam. We calculate the modulation expected in a wiggler from both a single frequency perspective and a coherent synchrotron radiation (CSR) perspective.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK083
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THPML033	Towards a Free Electron Laser Using Laser Plasma Acceleration	electron, laser, plasma, FEL	4723
	A. Loulergue, T. André, I.A. Andriyash, C. Benabderrahmane, P. Berteaud, F. Blache, C. Bourassin-Bouchet, F. Bouvet, F. Briquez, L. Chapuis, M.-E. Couprie, D. Dennetière, Y. Dietrich, J.P. Duval, M. El Ajjouri, T.K. El Ajjouri, A. Ghaith, C. Herbeaux, N. Hubert, M. Khojoyan, C.A. Kitegi, M. Labat, N. Leclercq, A. Lestrade, O. Marcouillé, F. Marteau, P. N'gotta, D. Oumbarek, F. Polack, P. Rommeluère, M. Sebdaoui, K.T. Tavakoli, M. Valléau, J. Vétéran, C. de Oliveira SOLEIL, Gif-sur-Yvette, France S. Bielawski, C. Evain, E. Roussel, C. Szwaj PhLAM/CERLA, Villeneuve d'Ascq, France S. Corde, J. Gautier, J.-P. Goddet, G. Lambert, B. Mahieu, V. Malka, J.P. Rousseau, S. Sebban, K. Ta Phuoc, A. Tafzi, C. Thaury LOA, Palaiseau, France O. S. Kononenko DESY, Hamburg, Germany S. Smartzev Weizmann Institute of Science, Physics, Rehovot, Israel
	Since the laser invention, the advent of X-ray Free Electron Lasers (FEL) half a century later, opens new areas for matter investigation. In parallel, the spectacular development of laser plasma acceleration (LPA) with several GeV beam acceleration in an extremely short distance appears very promising. As a first step, the qualification of the LPA with a FEL application sets a first challenge. Still, energy spread and beam divergence do not meet the state-of-the-art performance of the conventional accelerators and have to be manipulated to fulfill the FEL requirement. We report here on the undulator spontaneous emission measured after a transport manipulation electron beam line, using variable permanent magnet quadrupoles of variable strength for emittance handing and a demixing chicane equipped with a slit for the energy spread. Strategies of control electron beam position and dispersion have been elaborated. The measured undulator radiation provides an insight on the electron beam properties.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML033
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Paper

Title

Other Keywords

Page

TUPMF044

First Lasing of the CAEP THz FEL Facility Driven by a Superconducting Accelerator

FEL, laser, electron, undulator

1349

D. Wu, W. Bai, D.R. Deng, C.L. Lao, M. Li, S.F. Lin, X. Luo, L.J. Shan, X. Shen, H. Wang, J. Wang, Y. Xu, L.G. Yan, X. Yang, K. Zhou
CAEP/IAE, Mianyang, Sichuan, People's Republic of China
Y.H. Dou, X.J. Shu
Institute of Applied Physics and Computational Mathematics, People's Republic of China
W.-H. Huang
TUB, Beijing, People's Republic of China
X.Y. Lu
PKU, Beijing, People's Republic of China

Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190)
The stimulated saturation of the terahertz free electron laser at China Academy of Engineering Physics 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 wave 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 0.3 MW.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF044

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TUPMF045

Performance Optimization of a Prototype Undulator U38 Using Multi-Objective Genetic Algorithm

undulator, MMI, electron, laser

1353

L.G. Yan, D.R. Deng, P. Li, D. Wu
CAEP/IAE, Mianyang, Sichuan, People's Republic of China

Funding: The project of the national large-scale instrument development: 2011YQ130018; National Natural Science Foundation of China: 11505174, 11505173 and 11605190.
Genetic Algorithm (GA) is one of the most excellent method to search the optimal solution of a problem, which has been applied to solve various problems. It is hard to estimate shim applied on raw undulator precisely. There are many methods have been developed to solve the problem. In this proceeding, we measured the magnetic field distribution of prototype undulator U38 and concluded the shim using multi-objective GA. The code was written with the language of Python and based on the package pyevolve. A multi-objective fitness function was setup to implement the multi-objective optimization. Experimentally，performances satisfied the requirements by shimming U38 three times. The trajectory center deviation, peak-to-peak error and phase error are reduced to 0.15 mm, 0.49% and 1°.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF045

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TUPMF081

Microphonic Detuning Induced Coupler Kick Variation at LCLS-II

cavity, linac, laser, beam-loading

1456

T. Hellert
DESY, Hamburg, Germany
W. Ackermann, H. De Gersem
TEMF, TU Darmstadt, Darmstadt, Germany
C. Adolphsen, Z. Li, C.E. Mayes
SLAC, Menlo Park, California, USA

The LCLS-II free-electron laser will be an upgrade of the existing Linac Coherent Light Source (LCLS), including a 4 GeV CW superconducting linac based on the TESLA technology. The high quality factor of the cavity makes it very sensitive to vibrations. The shift of its eigenfrequency (i.e., detuning) will be compensated by the power source in order to assure a constant accelerating voltage. Significant variations of the forward power are expected which result in coupler kick variations induced by the fundamental power coupler. In this work we estimate the magnitude of trajectory jitter caused by these variations. High precision 3D field maps including standing and traveling-wave components for a cavity with the LCLS-II coupler design are presented.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF081

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THPMK026

Mobile Free-Electron Laser for Remote Atmospheric Survey

laser, FEL, electron, survey

4351

S. Johnson, G.A. Krafft, B. Terzić
ODU, Norfolk, Virginia, USA
G.A. Krafft
JLab, Newport News, Virginia, USA

Funding: This paper is authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05- 06OR23177. E.J. was supported by the Virginia Space Grant Consortium, grant number 16-589.
Reliable atmospheric surveys for carbon distributions will be essential to building an understanding of the Earth's carbon cycle and the role it plays in climate change. One of the core needs of NASA 's Active Sensing of CO2 Over Nights, Days and Seasons (ASCENDS) Mission is to advance the range and precision of current remote atmospheric survey techniques. The feasibility of using accelerator-based sources of infrared light to improve current airborne lidar systems has been explored. A literary review has been conducted to asses the needs of ASCENDS versus the current capabilities of modern atmospheric survey technology, and the parameters of a free electron laser (FEL) source were calculated for a lidar system that will meet these needs. By using the "Next Linear Collider" from the Stanford Linear Accelerator Center (SLAC), a mobile FEL-based lidar may be constructed for airborne surveillance. The calculated energy of the lidar pulse is 0.1 joule: this output is a two orders of magnitude gain over current lidar systems, so in principle, the mobile FEL will exceed the needs of ASCENDS. Further research will be required to asses other challenges to mobilizing the FEL technology.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK026

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THPMK028

Inverse Free Electron Laser Separatrix Crossing for Energy Gain and Stability

FEL, laser, undulator, electron

4354

N.S. Sudar, P. Musumeci
UCLA, Los Angeles, USA
D. Garzella
CEA, Gif-sur-Yvette, France

The laser wakefield accelerator (LWFA) has been proposed as a driver for next generation compact light sources. However, the beams produced by LWFA's typically exhibit correlated energy spread and energy jitter too large to drive the Free Electron Laser instability. We present here a novel scheme whereby using a highly non-linear strongly tapered undulator interaction directly after the LWFA we are able to trap and accelerate a large fraction of charge in the moving Inverse Free Electron Laser ponderomotive bucket. The final correlated energy spread and output energy are determined by the final bucket height and central energy of the ponderomotive bucket which are both determined by the stagnant undulator parameters, resulting in a significant decrease in the normalized energy spread (< 1%) and output energy jitter (< 1%). This interaction is treated both analytically and numerically.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK028

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THPMK045

Generation of High Power, High Intensity, Ultra Short X-Ray FEL Pulses

electron, laser, photon, emittance

4384

M.W. Guetg, Y. Ding, Z. Huang, A.A. Lutman
SLAC, Menlo Park, California, USA

X-ray Free Electron Lasers combine high pulse power, short pulse length, narrow bandwidth and a high degree of transverse coherence. Any increase in the photon pulse power, while shortening the pulse length, will further push the frontier on several key XFEL applications including single molecule imaging and novel nonlinear X-ray methods. We will present experimental results at the Linac Coherent Light Source raising its maximum power to more than 300% of the current limit, while reducing the photon pulse length to 10 fs. This was achieved by minimizing residual transverse-longitudinal centroid beam offsets and beam yaw, and by correcting the dispersion when operating over 6 kA peak current with a longitudinally shaped beam.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK045

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THPMK046

Advanced Fresh-Slice Beam Manipulations for FEL X-Ray Applications

electron, laser, undulator, controls

4387

A.A. Lutman, Y. Ding, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell
SLAC, Menlo Park, California, USA
C. Emma
UCLA, Los Angeles, USA

The recent development of the Fresh-slice technique granted control on which temporal slice lases in each undulator section in an X-ray Free-electron laser. Fresh-slice has been used for several experiments at the Linac Coherent Light Source for the generation of customizable high power two-color beams, and increased the performance of self-seeding schemes. As a novel development of the technique we present the demonstration of multistage self-amplified spontaneous-emission amplification schemes for the production of high-power ultra short pulses and improved control of the temporal duration of each pulse in multi-pulse schemes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK046

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THPMK061

Isolated Few-Cycle Pulse Generation in X-Ray Free-Electron Lasers

electron, bunching, FEL, laser

4434

D.J. Dunning, L.T. Campbell, N. Thompson
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
L.T. Campbell, B.W.J. MᶜNeil
USTRAT/SUPA, Glasgow, United Kingdom
D.J. Dunning, B.W.J. MᶜNeil, N. Thompson
Cockcroft Institute, Warrington, Cheshire, United Kingdom
J.D.A. Smith
TXUK, Warrington, United Kingdom

X-ray free-electron lasers are promising candidates to deliver high-brightness radiation pulses with duration significantly shorter than the present leading technique, high harmonic generation (HHG). This would extend attosecond science to probe ultrafast dynamics with even finer resolution. To do so requires breaking below a characteristic FEL timescale of typically a few hundred optical cycles, dictated by the relative slippage of the radiation and electrons during amplification. The concept of mode-locking enables this, with the mode-locked afterburner configuration predicted to deliver few-cycle pulses (~ 1 attosecond at hard X-ray). However such techniques would produce a train of closely separated pulses, while an isolated pulse would be preferable for some types of experiment. Building on previous techniques, a new concept has been developed for isolated few-cycle pulse generation and it is presented alongside simulation studies.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK061

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THPMK072

X-Band RF System as Linearizer for SXFEL

FEL, laser, electron, cavity

4467

J.H. Tan, W. Fang, Q. Gu, X.X. Huang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

High gradient accelerating structure is the core technology of compact linear collider facilities and compact free electron laser facilities. Meanwhile the important limitation of improving brightness in free electron laser facility is the non-linear energy spread, and the X-band accelerating structure can provide harmonic compensation in linac to linearize the bunch compression process. In this paper, a special X-band traveling-wave accelerating structure is primary designed for compact hard x-ray free electron laser facility. Then the structure is processed manufacturing, and realize high power experiment and linear bunch compression at Shanghai soft x-ray free electron laser facility.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK072

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THPMK083

Self-Modulation of a Relativistic Electron Beam in a Wiggler

electron, wiggler, laser, radiation

4492

J.P. MacArthur
Stanford University, Stanford, California, USA
J.P. Duris, Z. Huang, A. Marinelli, Z. Zhang
SLAC, Menlo Park, California, USA

Users at x-ray free-electron laser (FEL) facilities have shown strong interest in using single spike, coherent x-ray pulses to probe attosceond dynamics in atoms and molecules. Sub-femtosecond soft x-ray pulses may be obtained from an electron beam that has been modulated in a wiggler resonant with an external laser, the enhanced-SASE technique. We discuss a new way to produce this energy modulation, wherein the external laser is replaced by coherent radiation from the current spike on the tail of the electron beam. We calculate the modulation expected in a wiggler from both a single frequency perspective and a coherent synchrotron radiation (CSR) perspective.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK083

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THPML033

Towards a Free Electron Laser Using Laser Plasma Acceleration

electron, laser, plasma, FEL

4723

A. Loulergue, T. André, I.A. Andriyash, C. Benabderrahmane, P. Berteaud, F. Blache, C. Bourassin-Bouchet, F. Bouvet, F. Briquez, L. Chapuis, M.-E. Couprie, D. Dennetière, Y. Dietrich, J.P. Duval, M. El Ajjouri, T.K. El Ajjouri, A. Ghaith, C. Herbeaux, N. Hubert, M. Khojoyan, C.A. Kitegi, M. Labat, N. Leclercq, A. Lestrade, O. Marcouillé, F. Marteau, P. N'gotta, D. Oumbarek, F. Polack, P. Rommeluère, M. Sebdaoui, K.T. Tavakoli, M. Valléau, J. Vétéran, C. de Oliveira
SOLEIL, Gif-sur-Yvette, France
S. Bielawski, C. Evain, E. Roussel, C. Szwaj
PhLAM/CERLA, Villeneuve d'Ascq, France
S. Corde, J. Gautier, J.-P. Goddet, G. Lambert, B. Mahieu, V. Malka, J.P. Rousseau, S. Sebban, K. Ta Phuoc, A. Tafzi, C. Thaury
LOA, Palaiseau, France
O. S. Kononenko
DESY, Hamburg, Germany
S. Smartzev
Weizmann Institute of Science, Physics, Rehovot, Israel

Since the laser invention, the advent of X-ray Free Electron Lasers (FEL) half a century later, opens new areas for matter investigation. In parallel, the spectacular development of laser plasma acceleration (LPA) with several GeV beam acceleration in an extremely short distance appears very promising. As a first step, the qualification of the LPA with a FEL application sets a first challenge. Still, energy spread and beam divergence do not meet the state-of-the-art performance of the conventional accelerators and have to be manipulated to fulfill the FEL requirement. We report here on the undulator spontaneous emission measured after a transport manipulation electron beam line, using variable permanent magnet quadrupoles of variable strength for emittance handing and a demixing chicane equipped with a slit for the energy spread. Strategies of control electron beam position and dispersion have been elaborated. The measured undulator radiation provides an insight on the electron beam properties.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML033

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