STUDIES OF DOUBLY EXCITED STATES AND PHOTODETACHMENT 
IN NEGATIVE IONS
E. Lindroth and N. Brandefelt
Department of Atomic Physics, 
Stockholm University, Frescativ. 24, S-104 05 Stockholm, Sweden

We present a new ab initio approach to three-electron systems. 
Complex rotation combined with $B$-spline basis functions are 
used to construct and diagonalize the three-particle matrix.
All three electrons are treated on equal footing.
The method has been applied to 4^S -symmetry states of
He- above the single  ionization threshold, the same region where
accurate experiments are available. Several resonances observed in the
experiments, but previously not calculated, have been found.