DELTA, Dortmund, Germany
A light source facility employing the coherent harmonic generation (CHG) principle is being commissioned and operated since 2011 at DELTA, a 1.5-GeV electron storage ring at the TU Dortmund University, with the purpose of providing ultrashort coherent VUV radiation for time-resolved experiments. CHG is based on the interaction of ultrashort laser pulses with electrons in an undulator to generate coherent harmonics of the laser wavelength. Different methods have been used to optimize, detect and characterize the CHG radiation. One example is the study of transverse and longitudinal coherence properties in double-slit and Michelson experiments. Moreover, final steps towards performing pump-probe experiments to study ultrafast magnetic phenomena have been taken.
DELTA, Dortmund, Germany
PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France
KIT, Karlsruhe, Germany
At DELTA, a 1.5-GeV electron storage ring operated as a light source by the Center for Synchrotron Radiation at the TU Dortmund University, coherent ultrashort THz pulses are routinely generated by density-modulated electron bunches. Tracking simulations as well as experimental studies using ultrafast THz detectors and an FT-IR spectrometer aim at understanding the turn-by-turn evolution of the density modulation after an initial laser-electron interaction. Furthermore, intensity-modulated laser pulses are applied to create narrow-band THz radiation. This setup is part of the new short-pulse facility based on coherent harmonic generation.
DELTA, Dortmund, Germany
At the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University as a synchrotron radiation user facility, bunch-by-bunch feedback systems are in use for electron beam diagnostics and for the suppression of multibunch instabilities. An automatic readout of bunch position data allows a real-time modal analysis during machine operation. An excitation of particular multibunch modes enables the determination of growth and damping times for all modes independently. Further investigations of beam stability and natural damping times of all modes even below the instability threshold have been performed. In addition, first bunch-by-bunch data taken from the booster synchrotron are shown.