Stopping Cross Section in Carbon of 0.2-1.5-MeV Atoms with21≤Z1≤39

The stopping cross section $S=\frac{\mathrm{dE}}{\mathrm{NdR}}$ in thin carbon foils has been measured for ions with $21\le Z_1\le 39$ and with energies from 200 to 1500 keV. The experimental data have been corrected numerically for nuclear stopping, and the electronic stopping obtained is compared with theory. At constant projectile velocity, the periodic dependence of the electronic stopping cross section on the atomic number $Z_1$ of the incoming ions, previously reported for $Z_1\le 20$, is seen also in the present extended $Z_1$ range. The data show that the amplitude of the successive oscillations is approximately constant over the whole $Z_1$ range. The relative amplitude, however, tends to decrease with increasing velocity. The relative accuracy of the results is about 3%.