L x-ray production in 57La, 58Ce, 60Nd and 62Sm by 35-60Â MeV carbon and oxygen ions

L x-ray production cross sections have been measured for thin solid targets (∼50 μg/cm2) of 57La, 58Ce, 60Nd and 62Sm for 35-60 MeV C4+ and O5+ ions. There is an increase in these cross sections with the increasing projectile energy and the ratio of its atomic number to the atomic number of the target nucleus (Z1/Z2). The measured L x-ray production cross sections have been compared with the predicted values of the first Born approximation (FBA) and of the ECPSSR theory that accounts for the projectile energy loss and Coulomb deflection and the perturbed stationary-state and relativistic nature of the L-shell. For C4+ ions, there is a reasonable agreement with the ECPSSR predicted values for the higher Z elements (Nd and Sm), while for the lower Z elements (La and Ce), the FBA is in a better accord with the data. For O5+ ions, the FBA gives a better agreement for all the elements than the ECPSSR theory.