IPAC2011 - List of Authors (Gensch, M.)

Paper	Title	Page
MOPO037	Concept of Femtosecond Timing and Synchronization Scheme at ELBE	565
	M. Kuntzsch, A. Büchner, M. Gensch, A. Jochmann, T. Kirschke, U. Lehnert, F. Röser HZDR, Dresden, Germany M.K. Bock, M. Bousonville, M. Felber, T. Lamb, H. Schlarb, S. Schulz DESY, Hamburg, Germany
	The Radiation Source ELBE at Helmholtz-Zentrum Dresden-Rossendorf is undergoing an extension to offer capacity for various applications. The extension includes the setup of a THz-beamline with a dedicated laboratory and a beamline for electron-beam - high-power laser interaction. The current synchronization scheme offers stability on the picoseconds level. For pump-probe experiments using optical lasers, the desired synchronization between the pump and the probe pulse should be on the femtosecond scale. In the future there will be an optical synchronization system with a pulsed fiber laser as an optical reference. The laser pulses will be distributed over stabilized fiber links to the remote stations. It is planned to install EOM-based beam arrival time monitors (BAMs) in order to monitor the bunch jitter and to establish a beam-based feedback to reduce the jitter. Besides that, the timing system has to be revised to generate triggers for experiments with low repetition rate, two electron guns (thermionic DC, superconducting RF) and several lasers. The Poster will show the possible layout of the future Timing and Synchronization System at ELBE.

THPC084	Optical Afterburner for a SASE FEL: First Results from FLASH	3089
	M. Foerst CFEL, Hamburg, Germany M. Gensch HZDR, Dresden, Germany R. Riedel, E. Schneidmiller, N. Stojanovic, F. Tavella, M.V. Yurkov DESY, Hamburg, Germany
	Radiation Pulse from a Self-Amplified Spontaneous Emission Free Electron Laser (SASE FEL) consists out of spikes (wavepackets). Energy loss in the electron beam (averaged over radiation wavelength) also exhibits spiky behaviour on a typical scale of coherence length, and follows the radiation pulse envelope. These modulations of the electron beam energy are converted into large density (current) modulations on the same temporal scale with the help of a dispersion section, installed behind the x-ray undulator. Powerful optical radiation is then generated with the help of a dedicated radiator (afterburner). Envelope of the optical afterburner pulse is closely resembles the envelope of the x-ray pulse. We have recently demonstrated this principle at the Free Electron Laser in Hamburg (FLASH). We use THz undulator that is installed after the main X-ray as both dispersive element and radiator simultaneously. We characterize properties of the optical pulse using standard laser diagnostics techniques (i.e. FROG). Main result comes from the pulse duration measurement that we use to derive envelope of the x-ray radiation pulse duration which is in sub-100 fs range.

Paper

Title

Page

Concept of Femtosecond Timing and Synchronization Scheme at ELBE

565

M. Kuntzsch, A. Büchner, M. Gensch, A. Jochmann, T. Kirschke, U. Lehnert, F. Röser
HZDR, Dresden, Germany
M.K. Bock, M. Bousonville, M. Felber, T. Lamb, H. Schlarb, S. Schulz
DESY, Hamburg, Germany

The Radiation Source ELBE at Helmholtz-Zentrum Dresden-Rossendorf is undergoing an extension to offer capacity for various applications. The extension includes the setup of a THz-beamline with a dedicated laboratory and a beamline for electron-beam - high-power laser interaction. The current synchronization scheme offers stability on the picoseconds level. For pump-probe experiments using optical lasers, the desired synchronization between the pump and the probe pulse should be on the femtosecond scale. In the future there will be an optical synchronization system with a pulsed fiber laser as an optical reference. The laser pulses will be distributed over stabilized fiber links to the remote stations. It is planned to install EOM-based beam arrival time monitors (BAMs) in order to monitor the bunch jitter and to establish a beam-based feedback to reduce the jitter. Besides that, the timing system has to be revised to generate triggers for experiments with low repetition rate, two electron guns (thermionic DC, superconducting RF) and several lasers. The Poster will show the possible layout of the future Timing and Synchronization System at ELBE.

THPC084

Optical Afterburner for a SASE FEL: First Results from FLASH

3089

M. Foerst
CFEL, Hamburg, Germany
M. Gensch
HZDR, Dresden, Germany
R. Riedel, E. Schneidmiller, N. Stojanovic, F. Tavella, M.V. Yurkov
DESY, Hamburg, Germany

Radiation Pulse from a Self-Amplified Spontaneous Emission Free Electron Laser (SASE FEL) consists out of spikes (wavepackets). Energy loss in the electron beam (averaged over radiation wavelength) also exhibits spiky behaviour on a typical scale of coherence length, and follows the radiation pulse envelope. These modulations of the electron beam energy are converted into large density (current) modulations on the same temporal scale with the help of a dispersion section, installed behind the x-ray undulator. Powerful optical radiation is then generated with the help of a dedicated radiator (afterburner). Envelope of the optical afterburner pulse is closely resembles the envelope of the x-ray pulse. We have recently demonstrated this principle at the Free Electron Laser in Hamburg (FLASH). We use THz undulator that is installed after the main X-ray as both dispersive element and radiator simultaneously. We characterize properties of the optical pulse using standard laser diagnostics techniques (i.e. FROG). Main result comes from the pulse duration measurement that we use to derive envelope of the x-ray radiation pulse duration which is in sub-100 fs range.