Dissociative attachment of low energy electrons to vibrationally excited Na2<\sub> molecules
M.Keil*, C.Gebauer-Rochholz*, O.Kaufmann*,  W.Meyer#, and K.Bergmann*
* Fachbereich Physik der Universitaet, 67653 Kaiserslautern, Germany
# Fachbereich Chemie der Universitaet, 67653 Kaiserslautern, Germany
The formation of negative ions after attachment of low energy free electrons (Ee<\sub><40meV) 
from a novel photoelectron source with an energy spread of DeltaE<3meV to selectively 
vibrationally excited molecules Na2<\sub>(v") is studied. For v">12 the negative ion yield 
Nv"<\sub>(Ee<\sub>) decreases monotonically with increasing Ee<\sub>, while for v"=12 a broad 
maximum around Ee<\sub>=15meV is observed. Good agreement with theoretical results is found.