Atomic-field bremsstrahlung for electron energy 50 to 100 keV for Z from 6 to 92

Abstract

The absolute doubly differential cross sections, differential in photon emission angle and energy have been measured for 50, 75, and 100 keV incident electrons, for target elements C, Al, Cu, Y, Ag, Te, Tb, Au, Bi, and U for photons radiated at 90 degrees. Comparisons are made with the numerical calculations of Tseng and Pratt. As the absolute cross section measurements had an uncertainty of 22%, due mainly to a 20% uncertainty in target thickness, the relative cross sections are measured to test the photon energy dependent shape of the bremsstrahlung spectrum with an accuracy of 3%. The comparison between theory and experiment has also been made at a forward photon emission angle of zero degree for 100 keV incident electrons for the target elements Cu, Y, Ag, Te, Tb, Au, and U by the measurement of absolute cross sections. It is concluded that Pratt's theory is generally adequate to explain the bremsstrahlung process in this range of electron energies and atomic numbers, even though a few discrepancies have also been noted. An improved method of measuring the efficiency of the solid state detector has been developed by using bremsstrahlung. This method gives the efficiency curve for the entire range of energy under study.