At the heart of the IR facility FELIX is a free-electron laser that provides widely tunable radiation of high brightness in the mid- and far-infrared. The primary application of the facility is in studies of the vibrational dynamics of molecules, liquids and solids, but other applications requiring a very intense source in the spectral range covered, such as photo-ablation of tissue, near-field microscopy or linear spectroscopy of small-size samples, are equally appropriate. The wavelength range covered extends from 100 cm-1 to 2000 cm-1. Continuous tuning over an octave is possible in less than a minute. Optical pulses of only 6 cycles, corresponding to a pulse duration of 200 fs at 1000 cm-1, and with peak intensities in excess of 100 MW, can be produced. The maximum micropulse duration is about 100 cycles, which results in a minimum bandwidth of 0.4% (fwhm). The peripheral equipment includes a 40 T pulsed-field flow cryostat and a synchronized Ti sapphire laser pumped OPG/OPA, covering the range from 220 nm to 16 mm, that can be used either as 'second colour' or stand-alone.
Main Results: Under the contract a total number of 18 projects have been approved, two of which have been withdrawn after approval. The number of users involved in these projects is 22, whereof 15 are first time users to the facility. The total access delivered amounts to 1057 beamtime hours (1st year: 224 h, 2nd year: 422, 3rd year: 411 h).
Alexander van der Meer, FOM-Instituut voor Plasmafysica "Rijnhuizen", Edisonbaan, 14, Nieuwegein 3430BE, P.O. BOX 1207, The Netherlands