Channel Competition in Single Ionization of CS$^+$ by Intense Laser Pulses*

Employing a coincidence three-dimensional momentum imaging technique, we investigate the ultrafast, intense laser-induced ionization of CS$^+$. The analysis presented here focuses on the intensity-dependent branching ratio from 3$\times$10$^{14}$ to 3$\times$10$^{16}$ W/cm$^2$. The charge-symmetric C$^+$ + S$^+$ channel is dominant at all measured intensities, followed by CS$^{2+}$ and then C + S$^{2+}$, while C$^{2+}$ + S is not observed. The branching ratio measurement is assisted by {\it in situ} determination of the detection efficiency of all the product channels.