K-shell x-ray production of Na, Mg, Al, P, S, and Cl by 0.4-2.4 MeV11 H and 42He ions

K-shell x-ray cross sections for thin solid targets of llNa, 12Mg, 13A1, 15P, 16S, and 17C1 have been measured for 0.4-2.4 MeV H and He ions. Ratios of α(He)/4α(H) are determined as a function of energy/mass to reduce the experimental uncertainties. The absolute cross sections and the cross section ratios are compared to theoretical predictions of the binary encounter approximation, the plane wave Born approximation, and the perturbed stationary state theory with Coulomb deflection (CPSS). It is shown that the CPSS theory with an approximate correction for relativistic effects gives good estimates of the experimental data.