RELATIVISTIC EFFECTS ON THE H- RESONANCES CONVERGING TO THE H(N = 2) THRESHOLD

The series of H- resonances of P-1(o) symmetry predicted to converge e xponentially to all thresholds has been investigated below the H(n=2) threshold. It is shown that the series will be terminated already afte r the third resonance when the relativistic and radiative splitting of the H(n=2) states is considered. Resonance parameters of this third r esonance have been calculated with highly correlated wave functions. T he resonance is predicted to be situated 19 mu eV below H(2p(1/2)) wit h a width of 0.06 mu eV. Accurate resonance parameters are also given for the first two resonances and the photoabsorption cross section is calculated for the threshold region.