Structured photo-absorption spectra of ArHCl: fingerprints of overlapping broad resonances

Thousands of complex-scaled, square-integrable overlapping diffraction resonances of ArHCl were calculated. About 300 of them were found to be sufficient to describe the photo-absorption spectra, σtot(E), of ArHCl. It is first shown that their fingerprints may be seen in σtot(E), even as structures which can not be explained by the reflection principle. It is shown here that the rate of decay of a single ArHCl resonance which has the largest overlap with the initial ground electronic state can be obtained through the extrapolation of the survival probability to t=0.