X-RAY-EMISSION BY MULTIPLE PASSES OF ELECTRONS THROUGH PERIODIC AND CRYSTALLINE TARGETS MOUNTED INSIDE A SYNCHROTRON

The number of passes of high-energy electrons through multiple foil an d crystal radiators mounted inside of the Tomsk ''Sirius'' synchrotron , and the resulting increase in x-ray production efficiencies from the se radiators, have been measured. The influence of electron transmissi on on the spectral and spatial distributions of parametric x radiation and on the spatial distribution of transition radiation has also been observed. We find that multiple passes increase the yields of these s ources without destroying their angular distributions and spectra. Thu s, multiple passes of electrons through these novel radiators may make them useful as x-ray sources for scientific and industrial purposes. (C) 1998 American Institute of Physics.