Figure 1: TDCC wavefunctions obtained with the constrained damped relaxation method. (a) 1s²; (b) 2s²; (c) 2s3s, (d) 2p².

Figure 2: TDCC amplitudes $C_{\Phi}(t)=C_{2s^2}(t)$ at resonance energy (E_i= 31.6 eV). The incoming wavepacket have different spatial widths w from 5 a.u. to 30 a.u.. The thin dashed line is the (scaled) $A_{2s^2}$. The inset shows the oscillations of the amplitudes around the asymptotic exponential decay (notice the different scale).

Figure 3: TDCC amplitudes for $C_{\Phi}(t)=C_{2s^2}(t)$ at different incident energies. Thin dashed lines: perturbative calculations.

Figure: 4 Snapshots of the total wavefunction probability $\vert\Psi(r_1,r_2,t)\vert^2$ at different times during the $e^- + 1s$ collision. a) E_i= 25.0 eV (below the 2s² resonance energy); b) E_i= 31.6 eV (close to the 2s² resonance energy); b) E_i= 36.1 eV (close to the 2s3s resonance energy).