Aachen PK 2003 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

PV: Plenarvorträge

PV XII

PV XII: Plenary Talk

Thursday, March 20, 2003, 14:00–14:45, FO1

X-Ray Free-Electron Lasers : A new tool for plasma physics ? — •Thomas Tschentscher — HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg, GER

Short-wavelength free-electron lasers (FEL) pave the way for high-intensity X-ray beams with laser-like properties. Based on the principle of self-amplification of spontaneous emission (SASE) they employ high quality electron beams and long undulator sections. The radiation properties of X-ray FELs approach these of high-power laser facilities at the much shorter wavelength range of 0.1 to few nm. Peak values of several GW power and 10¹⁴ to 10¹⁸ W/cm² power density are anticipated, corresponding to 10¹² to 10¹⁴ photons per pulse at pulse duration around 100 fs. Scientific applications of X-ray FELs range from atomic physics via chemistry to biology. In plasma physics short-wavelength FELs, like the TTF2-FEL at DESY, Hamburg, or the proposed TESLA XFEL, will allow to apply new experimental techniques, thereby gaining new access to the understanding of plasmas. On the one hand, FEL radiation can be used as a short-wavelength probe in plasma diagnosis. On the other hand, focussing X-ray FEL radiation will allow to obtain power densities that can create solid-density plasmas by direct interaction of the X-rays with matter. Initial cluster beam experiments with 100 nm FEL radiation at the TTF-FEL indicate the existance of new mechanisms, different to these at optical wavelength, that allow electrons and ions to absorb high quantities of energy before leading to Coulomb explosion.