Production of ground state OH following electron impact on H2O

Laser-induced fluorescence (LIF) measurements of OH(X (2)Pi) production fol lowing electron impact on water have been carried out over an energy range from threshold to 300 eV. Data have been made absolute using existing measu rements of OH(X) production via dissociative attachment. The cross section reaches a maximum value of 2.1 X 10(-16) cm(2) at an energy of 75 eV. Dipol e-allowed processes are shown to dominate the production of OH(X) particula rly via the A(B-1(1)) repulsive state, though significant population of hig her rotational levels is demonstrated, indicating the relevance of other ch annels as in photodissociation. (C) 2001 American Institute of Physics.