FEL2011 - List of Authors (Ischebeck, R.)

Paper

Title

Page

sFLASH - Present Status and Commisioning Results

194

V. Miltchev, S. Ackermann, A. Azima, J. Bödewadt, F. Curbis, M. Drescher, E. Hass, Th. Maltezopoulos, M. Mittenzwey, J. Rönsch-Schulenburg, J. Roßbach, R. Tarkeshian
Uni HH, Hamburg, Germany
H. Delsim-Hashemi, K. Honkavaara, T. Laarmann, H. Schlarb, S. Schreiber, M. Tischer
DESY, Hamburg, Germany
R. Ischebeck
Paul Scherrer Institut, Villigen, Switzerland

The free-electron laser in Hamburg (FLASH) was previously being operated in the self-amplified spontaneous emission (SASE) mode, producing photons in the XUV wavelength range. Due to the start-up from noise the SASE-radiation consists of a number of uncorrelated modes, which results in a reduced coherence. One option to simultaneously improve both the coherence and the synchronisation between the FEL-pulse and an external laser is to operate FLASH as an amplifier of a seed produced using high harmonics generation (HHG). An experimental set-up - sFLASH, has been installed to test this concept for the wavelengths below 40 nm. The sFLASH installation took place during the planed FLASH shutdown in the winter of 2009/2010. The technical commissioning, which began in the spring of 2010, has been followed by FEL-characterization and seeded-FEL commissioning in 2011. In this contribution the present status and the sFLASH commissioning results will be discussed.

THPB06

Coherent Terahertz Radiation Monitors for Multiple Spectral Bands

572

R. Ischebeck, G.L. Orlandi, P. Peier, V. Schlott, B. Smit, C. Vicario, C. Zimmerli
Paul Scherrer Institut, Villigen, Switzerland
C. Gerth
DESY, Hamburg, Germany

The SwissFEL Injector Test Facility is destined for demonstrating electron beam parameters that are suitable for FEL operation. Of particular interest is the on-line measurement of longitudinal phase space properties, as this provides insight into the bunch compression process. The spectral distribution of diffraction radiation offers a robust way to assess bunch length and longitudinal profile. The bunch length at the SwissFEL Injector Test Facility can be varied by changing the photocathode laser. Diffraction radiation is emitted as the electron bunches pass through a hole in a titanium foil. The emitted Terahertz radiation has been simulated by the code THz Transport, and the propagation to the detectors has been modeled.

THPB30

SwissFEL Injector Test Facility – Test and Plans

625

M. Pedrozzi, M. Aiba, S. Bettoni, B. Beutner, A. Falone, R. Ganter, R. Ischebeck, F. Le Pimpec, G.L. Orlandi, E. Prat, S. Reiche, T. Schietinger, A. Trisorio, C. Vicario
Paul Scherrer Institut, Villigen, Switzerland

In August 2010 the Paul Scherrer Institute inaugurated the SwissFEL Injector test facility as a first step toward the Swiss hard X-ray FEL planned at PSI. The main purpose of the facility is to demonstrate and consolidate the generation of high-brightness beam as required to drive the 6 GeV SwissFEL accelerator. Additionally the injector serves as a platform supporting development and test of accelerator components/systems and optimization procedures foreseen for SwissFEL. In this paper we report on the present status of the commissioning with some emphasis on emittance measurements and component performances. The scientific program and long-term plans will be discussed as well.

FROA4

Response Matrix of Longitudinal Instrumentation in SwissFEL

652

R. Ischebeck, B. Beutner, R. Kalt, P. Peier, S. Reiche, T. Schilcher, V. Schlott
Paul Scherrer Institut, Villigen, Switzerland

Several sources of jitter and drift affect the longitudinal phase space dynamics of SwissFEL. To evaluate how drifts can be identified and corrected through appropriate diagnostics and beam-based feedbacks, the response matrix of possible longitudinal diagnostics on laser and RF stability is modeled. To this intent, photocathode laser intensity, laser arrival time, RF phases and RF amplitudes are individually varied in an ELEGANT model, and the expected response of on-line diagnostics on the simulated bunches is evaluated. By comparing the slope of the response to the expected resolution of the instrumentation, suitable monitors can be selected for a feedback.

Slides FROA4 [2.837 MB]

Paper	Title	Page
TUPA04	sFLASH - Present Status and Commisioning Results	194
	V. Miltchev, S. Ackermann, A. Azima, J. Bödewadt, F. Curbis, M. Drescher, E. Hass, Th. Maltezopoulos, M. Mittenzwey, J. Rönsch-Schulenburg, J. Roßbach, R. Tarkeshian Uni HH, Hamburg, Germany H. Delsim-Hashemi, K. Honkavaara, T. Laarmann, H. Schlarb, S. Schreiber, M. Tischer DESY, Hamburg, Germany R. Ischebeck Paul Scherrer Institut, Villigen, Switzerland
	The free-electron laser in Hamburg (FLASH) was previously being operated in the self-amplified spontaneous emission (SASE) mode, producing photons in the XUV wavelength range. Due to the start-up from noise the SASE-radiation consists of a number of uncorrelated modes, which results in a reduced coherence. One option to simultaneously improve both the coherence and the synchronisation between the FEL-pulse and an external laser is to operate FLASH as an amplifier of a seed produced using high harmonics generation (HHG). An experimental set-up - sFLASH, has been installed to test this concept for the wavelengths below 40 nm. The sFLASH installation took place during the planed FLASH shutdown in the winter of 2009/2010. The technical commissioning, which began in the spring of 2010, has been followed by FEL-characterization and seeded-FEL commissioning in 2011. In this contribution the present status and the sFLASH commissioning results will be discussed.

THPB06	Coherent Terahertz Radiation Monitors for Multiple Spectral Bands	572
	R. Ischebeck, G.L. Orlandi, P. Peier, V. Schlott, B. Smit, C. Vicario, C. Zimmerli Paul Scherrer Institut, Villigen, Switzerland C. Gerth DESY, Hamburg, Germany
	The SwissFEL Injector Test Facility is destined for demonstrating electron beam parameters that are suitable for FEL operation. Of particular interest is the on-line measurement of longitudinal phase space properties, as this provides insight into the bunch compression process. The spectral distribution of diffraction radiation offers a robust way to assess bunch length and longitudinal profile. The bunch length at the SwissFEL Injector Test Facility can be varied by changing the photocathode laser. Diffraction radiation is emitted as the electron bunches pass through a hole in a titanium foil. The emitted Terahertz radiation has been simulated by the code THz Transport, and the propagation to the detectors has been modeled.

THPB30	SwissFEL Injector Test Facility – Test and Plans	625
	M. Pedrozzi, M. Aiba, S. Bettoni, B. Beutner, A. Falone, R. Ganter, R. Ischebeck, F. Le Pimpec, G.L. Orlandi, E. Prat, S. Reiche, T. Schietinger, A. Trisorio, C. Vicario Paul Scherrer Institut, Villigen, Switzerland
	In August 2010 the Paul Scherrer Institute inaugurated the SwissFEL Injector test facility as a first step toward the Swiss hard X-ray FEL planned at PSI. The main purpose of the facility is to demonstrate and consolidate the generation of high-brightness beam as required to drive the 6 GeV SwissFEL accelerator. Additionally the injector serves as a platform supporting development and test of accelerator components/systems and optimization procedures foreseen for SwissFEL. In this paper we report on the present status of the commissioning with some emphasis on emittance measurements and component performances. The scientific program and long-term plans will be discussed as well.

FROA4	Response Matrix of Longitudinal Instrumentation in SwissFEL	652
	R. Ischebeck, B. Beutner, R. Kalt, P. Peier, S. Reiche, T. Schilcher, V. Schlott Paul Scherrer Institut, Villigen, Switzerland
	Several sources of jitter and drift affect the longitudinal phase space dynamics of SwissFEL. To evaluate how drifts can be identified and corrected through appropriate diagnostics and beam-based feedbacks, the response matrix of possible longitudinal diagnostics on laser and RF stability is modeled. To this intent, photocathode laser intensity, laser arrival time, RF phases and RF amplitudes are individually varied in an ELEGANT model, and the expected response of on-line diagnostics on the simulated bunches is evaluated. By comparing the slope of the response to the expected resolution of the instrumentation, suitable monitors can be selected for a feedback.
	Slides FROA4 [2.837 MB]