Ionisation cross sections of Cd, Sn, Te, I and Ba for protons and alpha particles

K-shell x-ray production cross sections of 48Cd, 50Sn, 52Te, 53I and 56Ba have been measured for alpha particles with energies between 2.2 and 2.8 MeV. In addition, production cross sections for 52Te have been measured for protons between 1.6 and 3 MeV. The values have been compared with the earlier experiments and with the theoretical predictions given by four different approaches: the perturbed stationary state model corrected for relativistic, projectile Coulomb deflection, and energy-loss effects, the plane-wave Born approximation (PWBA) with corrections for relativistic effects, effective binding and Coulomb deflection, the semiclassical approximation corrected for the same effects as the PWBA in its most recent formulation and, lastly, the binary model corrected for effective energy and relativistic effects. The different degrees of agreement for each theory in the cases examined are discussed. (author)