Excitation of H2O+ in e-H2O collisions

Inelastic collisions, between electrons of low and medium energies and H2O molecules, that give rise to the appearance of optical radiation were studied. An experiment was performed with a gas-filled cell using an extended beam of monokinetic electrons to excite the molecules. A spectrum appearing in the visible region was identified as belonging to H2O+. About 430 excitation cross sections attributed to 10 subbands of the <(A)over tilde (2)A(1)> - <(X)over tilde B-2(1)> system were measured. For a number of lines, measurements were made of the optical excitation functions in the range of energies from the excitation threshold to 200 eV.