L-SHELL X-RAY-PRODUCTION CROSS-SECTIONS IN FE-26, NI-28, CU-29, ZN-30, GA-31, AND GE-32 BY 0.5-MEV TO 5.0-MEV PROTONS

L-shell x-ray production cross sections by protons are reported for elements with x-ray energy between 704 and 1188 eV. The x rays were measured with a windowless Si(Li) detector. The efficiency of this detector, which is one of the major experimental problems for very-low-energy x-ray measurements, was determined by comparing spectra of atomic-field bremsstrahlung induced by 66.5-keV electrons on aluminum, silver, and gold with the theoretically known distributions. The x-ray production cross sections are compared with the first-order Born and perturbed-stationary-state theory with energy-loss, Coulomb deflection, and relativistic corrections of inner-shell ionization. Except for systematic but slight overpredictions of the data at the lowest proton velocities, both theories fit the measured data well.