Attosecond time delays in the body frame for photodetachment from molecular anions

Attosecond time delays in molecular photoionization at low energies are dominated by the contribution from the Coulomb phase, which diverges as the energy of the photoelectron decreases towards zero. With calculations on the core ionization of CN^- and C₂^- we demonstrate that in photodetachment of molecular anions the absence of the long-range Coulomb interaction in the final state can reveal the delays of narrow low-energy shape resonances that do not generally occur in photoionization. Delays of several femtoseconds are found for such resonances in these systems. Core-electron detachment experiments with coincidence detection of the emitted photoelectron and ion fragments open the possibility of detecting the time delays in the body frame due to the rapid Auger decay and subsequent fragmentation of the excited molecule. We show that the angular dependence of photodetachment time delays in the body frame is highly sensitive to short-range anisotropies in the electron-molecule interaction.