FEL2011 - List of Authors (Novikov, D.)

Paper	Title	Page
TUPA07	Study of a Silicon Based XFELO for the European XFEL	202
	J. Zemella, D. Novikov, M. Tolkiehn DESY, Hamburg, Germany J. Roßbach Uni HH, Hamburg, Germany H. Sinn European XFEL GmbH, Hamburg, Germany
	For the European XFEL in Hamburg three different SASE undulators are planed whose radiation output have a high peak brilliance up to 5.4·10³³ photon/s/mm²/mrad²/0.1% BW at wavelengths down to below 5·10^-11 m. The radiation pulses are nearly fully coherent in transverse direction but have a poor longitudinal coherence of about 0.3 fs. Several schemes were developed to get a better longitudinal coherence. In this paper an X-ray Free Electron Laser Oscillator is presented whose radiation output is nearly fully coherent in all directions. In contrast to previous schemes it is based on Silicon crystals rather than Diamond. The use of Silicon has the advantage of the availability of perfect crystals in nearly any size and crystal geometry but with a lower reflectivity and heat conduction than Diamond. To overcome the lower round-trip reflectivity of a Silicon cavity a longer undulator has to be used to get a sufficiently large gain. To reduce the heat load an extremely asymmetric crystal geometry has to be used to enlarge the beam spot on the crystal.

Paper

Title

Page

Study of a Silicon Based XFELO for the European XFEL

202

J. Zemella, D. Novikov, M. Tolkiehn
DESY, Hamburg, Germany
J. Roßbach
Uni HH, Hamburg, Germany
H. Sinn
European XFEL GmbH, Hamburg, Germany

For the European XFEL in Hamburg three different SASE undulators are planed whose radiation output have a high peak brilliance up to 5.4·10³³ photon/s/mm²/mrad²/0.1% BW at wavelengths down to below 5·10^-11 m. The radiation pulses are nearly fully coherent in transverse direction but have a poor longitudinal coherence of about 0.3 fs. Several schemes were developed to get a better longitudinal coherence. In this paper an X-ray Free Electron Laser Oscillator is presented whose radiation output is nearly fully coherent in all directions. In contrast to previous schemes it is based on Silicon crystals rather than Diamond. The use of Silicon has the advantage of the availability of perfect crystals in nearly any size and crystal geometry but with a lower reflectivity and heat conduction than Diamond. To overcome the lower round-trip reflectivity of a Silicon cavity a longer undulator has to be used to get a sufficiently large gain. To reduce the heat load an extremely asymmetric crystal geometry has to be used to enlarge the beam spot on the crystal.