Destruction of the $3s$ State in Atomic Hydrogen by Fast-Atom Impact on ${\mathrm{N}}_2$, Ar, and ${\mathrm{H}}_2$

Cross sections have been determined for the destruction of the $3s$ state in atomic hydrogen by 10-, 25-, and 35-keV hydrogen-atom impact on ${\mathrm{N}}_2$, Ar, and ${\mathrm{H}}_2$. The experimental values support the concept of two destruction mechanisms. One mechanism involves the collisional ionization of the excited atom, which has been treated quantitatively by Bates and Walker. The other mechanism involves electron capture by the fast-atom nucleus.