LINAC2016 - Classification: 1 Electron Accelerators and Applications / 1D FELs

Paper	Title	Page
MOOP10	FERMI FEL Linac Achievements and Upgrade
MOPLR002	use link to see paper's listing under its alternate paper code
	S. Di Mitri, G. D'Auria, M.B. Danailov, A. Fabris, M. Ferianis, L. Giannessi, C. Masciovecchio, C. Serpico, M. Svandrlik, D. Zangrando Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	FERMI is the Italian externally seeded free electron laser in the UV and soft x-rays, driven by a high brightness electron beam S-band plus X-band linac. In recent times, the linac has been upgraded, leading the final beam energy from the design value of 1.2 GeV to 1.5 GeV. Together with proper management of the electron beam quality, fundamental wavelengths down to 4 nm become therefore accessible to users. Additional upgrades concerning laser systems, diagnostics and RF structures are on the path. We present the FERMI FEL linac status, and provide an overview of running and future capabilities of the facility.
	Slides MOOP10 [1.714 MB]
	Poster MOOP10 [1.158 MB]
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MOP106006	Electro-Mechanical Modeling of the LCLS-II Superconducting Cavities	310
	O. Kononenko, C. Adolphsen, Z. Li, T.O. Raubenheimer, C.H. Rivetta SLAC, Menlo Park, California, USA
	Funding: Work supported by the Department of Energy, Office of Science, Office of Basic Energy Science, under Contract No. DEAC0276SF00515 The 4 GeV LCLS-II superconducting linac will contain 280, 1.3 GHz TESLA-style cavities operated CW at 16 MV/m. Because of the low beam current, the cavity bandwidth will be fairly small, about 32 Hz, which makes the field stability sensitive to detuning from external vibrations and He pressure fluctuations. Piezo-electric actuators will be used to compensate for the detuning, which historically has been difficult at frequencies above a few Hz due to excitation of cavity mechanical resonances. To understand this interaction better, we have been doing extensive modeling of the cavities including mapping out the mechanical modes and computing their coupling to pressure changes, Lorentz forces and piezo actuator motion. One goal is to reproduce the measured detuning response of the piezo actuators up to 1 kHz, which is sensitive to how the cavities are constrained within a cryomodule. In this paper, we summarize these results and their implications for suppressing higher frequency detuning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOP106006
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TU3A02	Linac-Based Free Electron Laser in China
	Z.T. Zhao SINAP, Shanghai, People's Republic of China
	The high gain free electron lasers (FEL) based on electron linacs can offer unprecedented performances for many science fields. There are several FEL facilities in China that have been built at different wavelength regimes. This talk will describe the latest development of three major FEL facilities in China including Shanghai Deep UV FEL at SINAP, DCLS VUV FEL at DICP and Shanghai X-ray FEL at SINAP.
	Slides TU3A02 [9.337 MB]
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TUOP01	Applying Transverse Gradient Undulators to Suppression of Microbunching Instability	380
TUPLR001	use link to see paper's listing under its alternate paper code
	D. Huang, H.X. Deng, C. Feng, D. Gu, Q. Gu, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	Funding: Major State Basic Research Development Program of China (2011CB808300). National Natural Science Foundation of China (NSFC), grant No. 11275253. The microbunching instability developed during the beam compression process in the linear accelerator (LIN-AC) of a free-electron laser (FEL) facility has always been a problem that degrades the lasing performance, and even no FEL is able to be produced if the beam quality is destroyed too much by the instability. A common way to suppress the microbunching instability is to introduce extra uncorrelated energy spread by the laser heater that heats the beam through the interaction between the electron and laser beam, as what has been successfully implemented in the Linac Coherent Light Source and Fermi@Elettra. In this paper, a simple and effective scheme is proposed to suppress the microbunching instability by adding two transverse gradient undulators (TGU) before and after the magnetic bunch compressor. The additional uncorrelated energy spread and the density mixing from the transverse spread brought up by the first TGU results in significant suppression of the instability. Meanwhile, the extra slice energy spread and the transverse emittance can also be effectively recovered by the second TGU. The magnitude of the suppression can be easily controlled by varying the strength of the magnetic fields of the TGUs. Theoretical analysis and numerical simulations demonstrate the capability of the proposed technique in the LINAC of an x-ray free-electron laser facility.
	Slides TUOP01 [1.148 MB]
	Poster TUOP01 [0.447 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUOP01
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TUPLR017	Summary of the Test and Installation of 10 MW MBKs for the XFEL Project	506
	V. Vogel (Fogel), Ł. Butkowski, A. Cherepenko, S. Choroba, J. Hartung, V.V. Kachaev, R. Wagner, S. Wiesenberg DESY, Hamburg, Germany
	For the European XFEL project, horizontal multi-beam klystrons (MBK) which produce RF power up to 10 MW, at an RF frequency of 1.3 GHz, 1.5 ms pulse length and 10 Hz repetition rate, were chosen as RF power sources. All MBKs have been manufactured by two companies, 22 tubes from Thales Electron Devices and 7 tubes from Toshiba Electron Tubes & Devices. In this article we will give a summary of the tube testing, conditioning and installation in the underground linear accelerator tunnel.
	Poster TUPLR017 [1.975 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR017
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TUPLR020	Commissioning of the Compact 14MeV LINAC for an FEL-Based THz Source	509
	Y.J. Pei, G. Feng, X.Y. He, Y. Hong, G. Huang, D. Jia, K. Jin, J. Liu, P. Lu, L. Shang, B.G. Sun, Zh. X. Tang, W. Wei, Z. Zhao USTC/NSRL, Hefei, Anhui, People's Republic of China L. Cao, Q.S. Chen, S. Hu, T. Hu, J. Li, Y.J. Liang, B. Qin, B. Tang, T. Tang, Y.Q. Xiong, Q. Zhang HUST, Wuhan, People's Republic of China W. Chen, Y.B. Wang, J. Zha Huazhong University of Science and Technology, State Key Laboratory of Advanced Electromagnetic Engineering and Technology,, Hubei, People's Republic of China G. Feng DESY, Hamburg, Germany Zh. X. Tang DICP, Dalian, People's Republic of China
	Commissioning the compact LINAC of 14Mev for a THz source based on FEL Y.J.Pei National Synchrotron Radiation laboratory, University of Science & Technology of China Abstract The compact LINAC of 14MeV is designed for a FEL which will produce a THz radiation through 30μm to 300μm. The LINAC was composed of a novel EC-ITC-RF gun, constant gradient travelling wave accelerator with a collinear absorbing load, focusing system, RF power system, beam diagnostic system, vacuum system, control system and so on. The LINAC was installed on November of 2014. Last year, we finished the install of the undulator and the optical resonance cavities. Now the LINAC has been testing and commissioning for THz radiation test. So far, the running beam parameters of the LINAC are as the following: Energy is of 13.58MeV macro pulse current is of 655mA macro pulse length of 1.2μsμpulse beam current is of 59A beam length of theμpulse is of 4ps energy spread of 0.33% normal beam emmitance is of 24.1mm.mrad.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR020
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FR2A01	Status of the PAL-XFEL	1042
	H.-S. Kang, D.E. Kim, K.W. Kim, I.S. Ko, T.-Y. Koo, H.-S. Lee, K.-H. Park PAL, Pohang, Kyungbuk, Republic of Korea
	The construction of the PAL-XFEL was completed at the end of 2015 and the FEL commissioning started from the beginning of 2016. The commissioning aims for the lasing of 0.5 nm FEL in the first campaign by July 2016, and for the lasing of 0.1 nm hard X-ray FEL in the second campaign by December 2016. The commissioning results of the 0.5 nm FEL lasing will be presented.
	Slides FR2A01 [92.474 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR2A01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOOP10

FERMI FEL Linac Achievements and Upgrade

use link to see paper's listing under its alternate paper code

S. Di Mitri, G. D'Auria, M.B. Danailov, A. Fabris, M. Ferianis, L. Giannessi, C. Masciovecchio, C. Serpico, M. Svandrlik, D. Zangrando
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

FERMI is the Italian externally seeded free electron laser in the UV and soft x-rays, driven by a high brightness electron beam S-band plus X-band linac. In recent times, the linac has been upgraded, leading the final beam energy from the design value of 1.2 GeV to 1.5 GeV. Together with proper management of the electron beam quality, fundamental wavelengths down to 4 nm become therefore accessible to users. Additional upgrades concerning laser systems, diagnostics and RF structures are on the path. We present the FERMI FEL linac status, and provide an overview of running and future capabilities of the facility.

Slides MOOP10 [1.714 MB]

Poster MOOP10 [1.158 MB]

Export •

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

MOP106006

Electro-Mechanical Modeling of the LCLS-II Superconducting Cavities

310

O. Kononenko, C. Adolphsen, Z. Li, T.O. Raubenheimer, C.H. Rivetta
SLAC, Menlo Park, California, USA

Funding: Work supported by the Department of Energy, Office of Science, Office of Basic Energy Science, under Contract No. DEAC0276SF00515
The 4 GeV LCLS-II superconducting linac will contain 280, 1.3 GHz TESLA-style cavities operated CW at 16 MV/m. Because of the low beam current, the cavity bandwidth will be fairly small, about 32 Hz, which makes the field stability sensitive to detuning from external vibrations and He pressure fluctuations. Piezo-electric actuators will be used to compensate for the detuning, which historically has been difficult at frequencies above a few Hz due to excitation of cavity mechanical resonances. To understand this interaction better, we have been doing extensive modeling of the cavities including mapping out the mechanical modes and computing their coupling to pressure changes, Lorentz forces and piezo actuator motion. One goal is to reproduce the measured detuning response of the piezo actuators up to 1 kHz, which is sensitive to how the cavities are constrained within a cryomodule. In this paper, we summarize these results and their implications for suppressing higher frequency detuning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOP106006

Export •

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TU3A02

Linac-Based Free Electron Laser in China

Z.T. Zhao
SINAP, Shanghai, People's Republic of China

The high gain free electron lasers (FEL) based on electron linacs can offer unprecedented performances for many science fields. There are several FEL facilities in China that have been built at different wavelength regimes. This talk will describe the latest development of three major FEL facilities in China including Shanghai Deep UV FEL at SINAP, DCLS VUV FEL at DICP and Shanghai X-ray FEL at SINAP.

Slides TU3A02 [9.337 MB]

Export •

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

TUOP01

Applying Transverse Gradient Undulators to Suppression of Microbunching Instability

380

TUPLR001

use link to see paper's listing under its alternate paper code

D. Huang, H.X. Deng, C. Feng, D. Gu, Q. Gu, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

Funding: Major State Basic Research Development Program of China (2011CB808300). National Natural Science Foundation of China (NSFC), grant No. 11275253.
The microbunching instability developed during the beam compression process in the linear accelerator (LIN-AC) of a free-electron laser (FEL) facility has always been a problem that degrades the lasing performance, and even no FEL is able to be produced if the beam quality is destroyed too much by the instability. A common way to suppress the microbunching instability is to introduce extra uncorrelated energy spread by the laser heater that heats the beam through the interaction between the electron and laser beam, as what has been successfully implemented in the Linac Coherent Light Source and Fermi@Elettra. In this paper, a simple and effective scheme is proposed to suppress the microbunching instability by adding two transverse gradient undulators (TGU) before and after the magnetic bunch compressor. The additional uncorrelated energy spread and the density mixing from the transverse spread brought up by the first TGU results in significant suppression of the instability. Meanwhile, the extra slice energy spread and the transverse emittance can also be effectively recovered by the second TGU. The magnitude of the suppression can be easily controlled by varying the strength of the magnetic fields of the TGUs. Theoretical analysis and numerical simulations demonstrate the capability of the proposed technique in the LINAC of an x-ray free-electron laser facility.

Slides TUOP01 [1.148 MB]

Poster TUOP01 [0.447 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUOP01

Export •

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

TUPLR017

Summary of the Test and Installation of 10 MW MBKs for the XFEL Project

506

V. Vogel (Fogel), Ł. Butkowski, A. Cherepenko, S. Choroba, J. Hartung, V.V. Kachaev, R. Wagner, S. Wiesenberg
DESY, Hamburg, Germany

For the European XFEL project, horizontal multi-beam klystrons (MBK) which produce RF power up to 10 MW, at an RF frequency of 1.3 GHz, 1.5 ms pulse length and 10 Hz repetition rate, were chosen as RF power sources. All MBKs have been manufactured by two companies, 22 tubes from Thales Electron Devices and 7 tubes from Toshiba Electron Tubes & Devices. In this article we will give a summary of the tube testing, conditioning and installation in the underground linear accelerator tunnel.

Poster TUPLR017 [1.975 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR017

Export •

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

TUPLR020

Commissioning of the Compact 14MeV LINAC for an FEL-Based THz Source

509

Y.J. Pei, G. Feng, X.Y. He, Y. Hong, G. Huang, D. Jia, K. Jin, J. Liu, P. Lu, L. Shang, B.G. Sun, Zh. X. Tang, W. Wei, Z. Zhao
USTC/NSRL, Hefei, Anhui, People's Republic of China
L. Cao, Q.S. Chen, S. Hu, T. Hu, J. Li, Y.J. Liang, B. Qin, B. Tang, T. Tang, Y.Q. Xiong, Q. Zhang
HUST, Wuhan, People's Republic of China
W. Chen, Y.B. Wang, J. Zha
Huazhong University of Science and Technology, State Key Laboratory of Advanced Electromagnetic Engineering and Technology,, Hubei, People's Republic of China
G. Feng
DESY, Hamburg, Germany
Zh. X. Tang
DICP, Dalian, People's Republic of China

Commissioning the compact LINAC of 14Mev for a THz source based on FEL Y.J.Pei National Synchrotron Radiation laboratory, University of Science & Technology of China Abstract The compact LINAC of 14MeV is designed for a FEL which will produce a THz radiation through 30μm to 300μm. The LINAC was composed of a novel EC-ITC-RF gun, constant gradient travelling wave accelerator with a collinear absorbing load, focusing system, RF power system, beam diagnostic system, vacuum system, control system and so on. The LINAC was installed on November of 2014. Last year, we finished the install of the undulator and the optical resonance cavities. Now the LINAC has been testing and commissioning for THz radiation test. So far, the running beam parameters of the LINAC are as the following: Energy is of 13.58MeV macro pulse current is of 655mA macro pulse length of 1.2μsμpulse beam current is of 59A beam length of theμpulse is of 4ps energy spread of 0.33% normal beam emmitance is of 24.1mm.mrad.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR020

Export •

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

FR2A01

Status of the PAL-XFEL

1042

H.-S. Kang, D.E. Kim, K.W. Kim, I.S. Ko, T.-Y. Koo, H.-S. Lee, K.-H. Park
PAL, Pohang, Kyungbuk, Republic of Korea

The construction of the PAL-XFEL was completed at the end of 2015 and the FEL commissioning started from the beginning of 2016. The commissioning aims for the lasing of 0.5 nm FEL in the first campaign by July 2016, and for the lasing of 0.1 nm hard X-ray FEL in the second campaign by December 2016. The commissioning results of the 0.5 nm FEL lasing will be presented.

Slides FR2A01 [92.474 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR2A01

Export •

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