title: Absolute Doubly Differential Cross Section for Bremsstrahlung Spectra Produced in 7.0 keV e<formula>^-</formula>--Ag and Au Collisions.
abstract: The first experimental data are presented for the absolute doubly differential cross section (DDCS) for non-characteristics (bremsstrahlung) X-ray spectra produced by 7.0 keV electron bombardment of (semi-thick) targets of silver and gold at a photon detection angle of 90 degree. The bremsstrahlung spectra are corrected for detector's efficiency as well as for target effects; namely, electron energy loss, backscattering and photon-attenuation in the target. The DDCS values so obtained are compared with the predictions of a thin target bremsstrahlung theory. The agreement between experiment and theory for DDCS both in magnitude and shape is found to be satisfactory within the systematic experimental uncertainty of about 27%. penetrating electrons into the thick targets and the depth distribution of photons generated inside the targets are expected to be also present in the interaction. However, the contributions of these effects to the DDCS have not been taken into consideration. Various possible reasons for the existing discrepancy between experiment and theory are pointed out.
authors.affiliation: Atomic Physics Laboratory, Physics Department, Banaras Hindu University, Varanasi  221 005, India.
authors.forename: S K
authors.initials: SK
authors.lastname: Goel
authors.forename: R
authors.initials: R
authors.lastname: Shanker