Experimental study of electron transfer in multiply charged iron-ion collisions with atomic hydrogen

The measurement of electron-transfer cross sections $\sigma$ in ion collisions with atomic hydrogen has been extended to iron ions with mass number $A=56\mathrm{}$, charges $q$ between +4 and +13, and specific energies $\frac{E}{A}$ between 27 and 290 keV/amu. The charge-state dependences of $\sigma$ range from $q^{1.5}$ at lower values of $q$ and $E$ to $q^3$ for higher values of these quantities. An empirical scaling relationship is found for converting ${\mathrm{H}}^{+}$ +H cross sections into those for ${\mathrm{Fe}}^{q+}$ + H. Several effects correlated with shell structure in the incident ion are observed. Our results are not explained by presently available theoretical calculations.