in both spectra, between the 70th and 80th harmonics, which are discussed below. Due to the logarithmic scale on which all of these HHG spectra are plotted, differences between the TDHF and TDKS results above the 30 harmonic order are generally < 10 -6 on an absolute intensity scale, which is small considering that the major peaks at low harmonic orders are ∼ 10 +10 -10 +15 on the same scale. Figure shows HHG spectra computed at the HF/5aug-cc-pVTZ level using four different CAPs, defined by different choices of the parameters r 0 and η in Eq. ( ). Unlike the previous simulations, each of which used an impulsive field and were propagated for 1,500 a.u., these simulations used a continuous-wave field and were propagated for 5,000 a.u. Figure uses the same set of CAP parameters as in Fig. and we will use this spectrum as a reference in examining the effects of the CAP parameters. As compared to the simulation using an impulsive field (Fig. ), the corresponding simulation with a continuous wave (Fig. ) provides a much better resolved set of peaks all the way up to the anticipated harmonic cutoff, because the system experience more cycles of the laser field. Beyond the 30th harmonic the intensity drops dramatically and the baseline is reduced by several orders of magnitude as compared to the corresponding simulation using an impulsive field. Fictitious peaks around the 60th, 75th, and 93rd harmonic orders can be observed in both simulations, but their intensity is reduced in the continuous-wave calculation.