On the Discovery of Coherent Bremsstrahlung in a Single Crystal at the Frascati National Laboratories

Since the end of 1950s the Frascati National Laboratories have started intense research program devoted to studying the coherent phenomena of relativistic electron interactions in crystals. First results were impressive: Frascati's Spectrometer has first detected coherent radiation by electrons in crystals, i.e. coherent bremsstrahlung. The discovery not only proved the Ferretti-Uberall prediction, but also has corrected the theory of coherent bremstrahlung. Carrying out intensive studies on coherent radiation phenomena in crystals a number of innovative techniques to measure fine features of radiation, such as polarization measurents, was developed. The Frascati's group was even close for the first time to observe channeling radiation discovered about two decades later the pioneering work on coherent bremsstrahlung.