This award will support a group of U.S. researchers under the direction of Professor John E. Walsh of Dartmouth College, New Hampshire, to collaborate with a group of Italian scientists headed by Dr. Gian-Piero Gallerano of the ENEA Research Center in Frascati, Italy. The investigators intend to produce a moderate (10-100KW) source of tunable, short-pulse (10-30ps) coherent radiation at FIR and IR wavelengths with the Frascati Cerenkov Free-Electron Laser (C-FEL). Such a source should find ample application to a wide range of research topics, including excitations in thin films, biophysics plasma diagnostics, and the study of transient excitations in large molecules. For this collaboration, which has been ongoing for the last four years, Dartmouth researchers provided the original design concept, the basic theory for the device, and construction of a C-FEL resonator. The ENEA (Frascati) laboratory has provided laboratory space, a 5-Mev microtron accelerator, a beam transport channel and beam-focussing monitoring and diagnostic equipment. A particular advantage of the C-FEL schemes is that in comparison with other FEL schemes, the beam energy required for operation at shorter FIR and IR wavelengths is modest. This results in a source that is compact and thus ultimately practical for a wider range of applications.
