Low energy channeling radiation experiments in a germanium crystal

Channeling radiation from relativistic electrons has been measured in germa nium at low electron energies (6.00, 9.00 and 10.18 MeV) using a 20 mu m th ick germanium crystal at the Darmstadt superconducting linear accelerator S -DALINAC. The results of the theoretical calculations (planar case) were co mpared with experimental data and are in reasonable agreement with the obse rved results. The channeling radiation energies scale as gamma(5/3) (gamma is the ratio of the electron total energy and its rest mass) for the deeply bound states (states localized in the vicinity of the atomic plane) and ga mma(2) for states localized between the channeling planes. We have also mea sured the intensity of the 1-0 transition along the (110) plane as a functi on of the tilt angle (angle between electron beam and plane) and found that channeling radiation occurs even when the tilt angle is larger than the cr itical angle, due to multiple scattering. (C) 1999 Elsevier Science B.V. Al l rights reserved.