M-shell x-ray production by C, N and O ions

M-shell X-ray production cross sections for Os, Au and Th targets were measured for C, N and O ions at incident energies from 1.2 MeV to about 36 MeV. Experimental M-shell ionization cross sections, derived by using the effective M-shell fluorescence yields, are compared with the prediction of the SCA calculations with relativistic hydrogenic wave functions. The calculations were performed both in the separated-atom (SA) and united-atom (UA) limits to simulate the binding effect. Generally, the data show better agreement with the SCA-UA cross sections for lower energies and with the SCA-SA predictions for higher energies. For C and O impact on the Au target at about 2 MeV/amu the present data are compared with available experimental results and theoretical predictions of the ECPSSR theory.