FEL2011 - List of Keywords (klystron)

Paper	Title	Other Keywords	Page
TUOBI2	First Lasing in the Water Window with 4.1nm at FLASH	FEL, radiation, electron, undulator	164
	S. Schreiber DESY, Hamburg, Germany
	The free-electron laser facility FLASH at DESY, Germany has been upgraded. The electron beam energy has been increased from 1 to 1.25 GeV by adding a 7th superconducting accelerating module. In September 2010, for the first time, lasing in the water window at a fundamental wavelength of 4.1 nm has been achieved. The water window is a wavelength region between 2.3 and 4.4 nm in which water is transparent for light. This remarkable achievement opens the possibility for new class of experiments, especially for biological samples in aqueous solution.
	Slides TUOBI2 [6.481 MB]

TUPA20	Third Harmonic Lasing in the NIJI-IV Storage Ring Free-Electron Lasers	FEL, cavity, electron, storage-ring	239
	N. Sei, H. Ogawa, K. Yamada AIST, Tsukuba, Ibaraki, Japan
	Funding: This study was financially supported by the Budget for Nuclear Research of the Ministry of Education, Culture, Sports, Science and Technology. Studies of the storage ring free electron lasers (SRFELs) and their application experiments have progressed with the compact storage ring NIJI-IV at the National Institute of Advanced Industrial Science and Technology. We achieved SRFEL oscillations on the third harmonic in the near-infrared region. The measured gain and power of the third-harmonic FEL were consistent with those obtained by the storage ring FEL theory. The measured linewidth of the third-harmonic FEL was less than that of the fundamental FEL, and its pulse width was wider than that of the fundamental FEL. Our studies would be useful for a study of x-ray FEL oscillations with a resonator. In this presentation, characteristics of the higher-harmonic FELs with the NIJI-IV will be discussed in detail. : N. Sei et al., J. Phys. Soc. Jpn. 79 (2010) 093501.

TUPB18	Preliminary Studies of a Possible Normal-conducting Linac Option for the UK's New Light Sourc	linac, FEL, gun, electron	295
	R.P. Walker, C. Christou, J.H. Han Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	A Conceptual Design Report for a major new soft-Xray light source facility for the UK, the New Light Source (NLS), based on high repetition rate free-electron lasers driven by a cw superconducting L-band linac was completed in May 2010. While the science case for such a facility was considered very strong, due to funding restrictions the NLS design project, supported by STFC and Diamond Light Source, was terminated after completion of the CDR. Since then we have been giving some preliminary considerations to a possible alternative option for the NLS which could provide similar performance but at reduced repetition rate, and potentially reduced cost, based on normal conducting technology. In this report we summarise the work done so far, including possible operating parameters and performance, as well as an assessment of relative costs of different frequency options.

WEPA15	S-band High Gradient Linac for a Compact XFEL	linac, acceleration, FEL, LLRF	356
	F. Wang SLAC, Menlo Park, California, USA
	With the successful operation of the first hard X-ray FEl, LCLS, other XFEL facilities are being developed worldwide. Due to the limited site size, many proposed XFELs are based on C-band technology. Switching from S-band to C-band enables a higher acceleration gradient (>35 MV/m) that is nearly double that of the SLAC S-band Linac. Based on the high gradient research, it found that the actually operational gradient is scaled as 1/6 power of the required rf pulse length at constant rf breakdown rate. Therefore, it is possible to have a S-band linac at higher gradient (>35MV/m) operated at very short rf pulse length, such like the single/two bunch operating XFEL.

WEPA16	Quasi-cw Normal Conducting Linac for Soft XFEL	linac, wakefield, dipole, factory	359
	F. Wang, C. Adolphsen SLAC, Menlo Park, California, USA
	The CW operating soft XFELs have been proposed worldwide to serve large user community simultaneous. In principle, the superconducting linac technology is the only solution to realize such a cw light source. However, large amount of R&D efforts are still needed to build such a linac, which could delay such facility for a significant long period. Therefore, it will be very important to explore the other technology based such XFEL, like the normal conducting based quasi-cw (10s kHz) linac. With the initial study, it turns out that such a quasi-cw linac could be built with L-band (1.3 GHz) or X-band (11.4 GHz) technology. And the L-band devices for such a linac have been developed in the frame work of ILC.

FROAI1	State-of-the-Art RF Distribution and Synchronization Techniques	laser, controls, cavity, electron	633
	Y. Otake RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	In a recent FEL accelerator, the temporal stability of an accelerated electron beam is the most crucial problem to achieve stable lasing. The demanded temporal stability is less than several ten fs (rms) to stably keep an extremely high peak current formed at a bunch compressor, as well as attaining required temporal resolution of a pump-probe experiment. To realize this stability, elaborate rf distribution and synchronization system for the accelerator are strongly needed. One of the most promising methods to realize the system is unified instruments of laser technology and electrical technology. Because the system can control an rf phase based on optical wavelength resolution and reduce effects of environmental perturbations arising from temperature variation, vibration and electrical noise. Many institutes already employed the unified system comprising instruments, such as optical fiber signal transmission and in-phase and quadrature rf vector manipulation. We recently obtained less than 30 fs (rms) temporal fluctuation of electron beams at XFEL/SPring-8 “SACLA” by using this kind system. This paper reviews state of the art timing systems using the unified technology for FEL.

FROAI2	All-optical Femtosecond Timing System for the Fermi@Elettra FEL	laser, FEL, linac, electron	641
	M. Ferianis, A.O. Borga, A. Bucconi, M. Predonzani, F. Rossi ELETTRA, Basovizza, Italy L. Pavlovič University of Ljubljana, Faculty of Electrical Engineering, Ljubljana, Slovenia
	FERMI@Elettra, a 4th generation light source under commissioning at Sincrotrone Trieste, is the first FEL facility to use an all-optical system for femtosecond timing and synchronization over the entire facility ranging from the photoinjector, linac, FEL and beamline endstations. The system is a unique combination of state-of-the-art femtosecond timing distribution based on pulsed and CW stabilized optical fiber links. We describe the details of this unique system and present the performance to date.
	Slides FROAI2 [4.210 MB]

Paper

Title

Other Keywords

Page

TUOBI2

First Lasing in the Water Window with 4.1nm at FLASH

FEL, radiation, electron, undulator

164

S. Schreiber
DESY, Hamburg, Germany

The free-electron laser facility FLASH at DESY, Germany has been upgraded. The electron beam energy has been increased from 1 to 1.25 GeV by adding a 7th superconducting accelerating module. In September 2010, for the first time, lasing in the water window at a fundamental wavelength of 4.1 nm has been achieved. The water window is a wavelength region between 2.3 and 4.4 nm in which water is transparent for light. This remarkable achievement opens the possibility for new class of experiments, especially for biological samples in aqueous solution.

Slides TUOBI2 [6.481 MB]

TUPA20

Third Harmonic Lasing in the NIJI-IV Storage Ring Free-Electron Lasers

FEL, cavity, electron, storage-ring

239

N. Sei, H. Ogawa, K. Yamada
AIST, Tsukuba, Ibaraki, Japan

Funding: This study was financially supported by the Budget for Nuclear Research of the Ministry of Education, Culture, Sports, Science and Technology.
Studies of the storage ring free electron lasers (SRFELs) and their application experiments have progressed with the compact storage ring NIJI-IV at the National Institute of Advanced Industrial Science and Technology. We achieved SRFEL oscillations on the third harmonic in the near-infrared region*. The measured gain and power of the third-harmonic FEL were consistent with those obtained by the storage ring FEL theory. The measured linewidth of the third-harmonic FEL was less than that of the fundamental FEL, and its pulse width was wider than that of the fundamental FEL. Our studies would be useful for a study of x-ray FEL oscillations with a resonator. In this presentation, characteristics of the higher-harmonic FELs with the NIJI-IV will be discussed in detail.
*: N. Sei et al., J. Phys. Soc. Jpn. 79 (2010) 093501.

TUPB18

Preliminary Studies of a Possible Normal-conducting Linac Option for the UK's New Light Sourc

linac, FEL, gun, electron

295

R.P. Walker, C. Christou, J.H. Han
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

A Conceptual Design Report for a major new soft-Xray light source facility for the UK, the New Light Source (NLS), based on high repetition rate free-electron lasers driven by a cw superconducting L-band linac was completed in May 2010. While the science case for such a facility was considered very strong, due to funding restrictions the NLS design project, supported by STFC and Diamond Light Source, was terminated after completion of the CDR. Since then we have been giving some preliminary considerations to a possible alternative option for the NLS which could provide similar performance but at reduced repetition rate, and potentially reduced cost, based on normal conducting technology. In this report we summarise the work done so far, including possible operating parameters and performance, as well as an assessment of relative costs of different frequency options.

WEPA15

S-band High Gradient Linac for a Compact XFEL

linac, acceleration, FEL, LLRF

356

F. Wang
SLAC, Menlo Park, California, USA

With the successful operation of the first hard X-ray FEl, LCLS, other XFEL facilities are being developed worldwide. Due to the limited site size, many proposed XFELs are based on C-band technology. Switching from S-band to C-band enables a higher acceleration gradient (>35 MV/m) that is nearly double that of the SLAC S-band Linac. Based on the high gradient research, it found that the actually operational gradient is scaled as 1/6 power of the required rf pulse length at constant rf breakdown rate. Therefore, it is possible to have a S-band linac at higher gradient (>35MV/m) operated at very short rf pulse length, such like the single/two bunch operating XFEL.

WEPA16

Quasi-cw Normal Conducting Linac for Soft XFEL

linac, wakefield, dipole, factory

359

F. Wang, C. Adolphsen
SLAC, Menlo Park, California, USA

The CW operating soft XFELs have been proposed worldwide to serve large user community simultaneous. In principle, the superconducting linac technology is the only solution to realize such a cw light source. However, large amount of R&D efforts are still needed to build such a linac, which could delay such facility for a significant long period. Therefore, it will be very important to explore the other technology based such XFEL, like the normal conducting based quasi-cw (10s kHz) linac. With the initial study, it turns out that such a quasi-cw linac could be built with L-band (1.3 GHz) or X-band (11.4 GHz) technology. And the L-band devices for such a linac have been developed in the frame work of ILC.

FROAI1

State-of-the-Art RF Distribution and Synchronization Techniques

laser, controls, cavity, electron

633

Y. Otake
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan

In a recent FEL accelerator, the temporal stability of an accelerated electron beam is the most crucial problem to achieve stable lasing. The demanded temporal stability is less than several ten fs (rms) to stably keep an extremely high peak current formed at a bunch compressor, as well as attaining required temporal resolution of a pump-probe experiment. To realize this stability, elaborate rf distribution and synchronization system for the accelerator are strongly needed. One of the most promising methods to realize the system is unified instruments of laser technology and electrical technology. Because the system can control an rf phase based on optical wavelength resolution and reduce effects of environmental perturbations arising from temperature variation, vibration and electrical noise. Many institutes already employed the unified system comprising instruments, such as optical fiber signal transmission and in-phase and quadrature rf vector manipulation. We recently obtained less than 30 fs (rms) temporal fluctuation of electron beams at XFEL/SPring-8 “SACLA” by using this kind system. This paper reviews state of the art timing systems using the unified technology for FEL.

FROAI2

All-optical Femtosecond Timing System for the Fermi@Elettra FEL

laser, FEL, linac, electron

641

M. Ferianis, A.O. Borga, A. Bucconi, M. Predonzani, F. Rossi
ELETTRA, Basovizza, Italy
L. Pavlovič
University of Ljubljana, Faculty of Electrical Engineering, Ljubljana, Slovenia

FERMI@Elettra, a 4th generation light source under commissioning at Sincrotrone Trieste, is the first FEL facility to use an all-optical system for femtosecond timing and synchronization over the entire facility ranging from the photoinjector, linac, FEL and beamline endstations. The system is a unique combination of state-of-the-art femtosecond timing distribution based on pulsed and CW stabilized optical fiber links. We describe the details of this unique system and present the performance to date.

Slides FROAI2 [4.210 MB]