The time-dependent changes in the MS, PES, and a typical ion momentum distribution map of the C 4 H + x ion are shown in Figure . The momentum map illustrates the evolution of the momentum of the ion extracted from the ion VMI (as in Figure ) as a function of pump-probe delay t. In the pump-probe-dependent MS, we see similar trends for the fragmentation dynamics of PAHs as were observed with the XUV-pumped experiments. In the t < 0 region, we see more of the parent species than in the t > 0 region. For the fragments, this trend is inverse: for t < 0, we see fewer ions than for t > 0. Such behavior indicates that the pump pulse produces an excited state ensemble, and the probe pulse destroys it by pumping even more energy to overcome fragmentation thresholds. This is observed for the PAH in both XUV-excited regimes probed with IR and VIS pulses as well as for benzene and toluene excited by a strong-field laser. Near the temporal overlap of the two laser pulses (t = 0), there is a strong increase in the ion production of all kinds of ions, as well as an increase in the yields of the ATI peaks. The PES (Figure ) shows qualitatively the same ATI spectrum given by Equation ATI band order k Lifetime, fs Parent species Lifetime, fs ) and the monodehydrogenated FLU monocation (C 13 H + 9 ). The uncertainties of the lifetimes are the 1σ values obtained from the Monte-Carlo sampling.