Semiprecision Calculations of Electron-Hydrogen Resonances

Abstract

Reliable calculations of the shift ($\Delta$) and width ($\Gamma$) are combined with precision calculations of the unshifted energy ($\mathcal{E}$) to obtain the position and width of the lowest ${}_{}{}^1{}_{}{}^{}S$ resonance in $e-\mathrm{H}$ scattering. These values together with our previous results for the two higher, ${}_{}{}^3{}_{}{}^{}P$ and ${}_{}{}^1{}_{}{}^{}D$, resonances are compared with the previous most-accurate calculations and some differences are noted. Comparison with experiment is also made.