Figure 4
Responses of photoions vs input laser fluence in the J = 2–1–1–0 scheme: (a) The first excited-state intermediate (\({z}^{3}{{\bf{D}}}_{1}^{^\circ }\leftarrow {a}^{3}{{\bf{F}}}_{2}\)), (b) the second excited-state intermediate (\({e}^{5}{{\bf{F}}}_{1}\leftarrow {z}^{3}{{\bf{D}}}_{1}^{^\circ }\)), and (c) the third excited-state intermediate (J′ = 0 ← e5F1). The black dots and red curves depict the observed and the fitted, respectively, by Eq. 3, and the dashed lines denote its asymptotes and tangents at each zero fluence. The arrows indicate the nominal saturation fluence, and the obtained cross-sections σ are listed in Table 2.
