We use $R$-matrix theory with time dependence (RMT) to investigate multiphoton ionization of ground-state atomic carbon with initial orbital magnetic quantum number $M_L=0$ and $M_L=1$ at a laser wavelength of 390 nm and peak intensity of ${10}^{14}{\mathrm{W}/\mathrm{cm}}^2$. Significant differences in ionization yield and ejected-electron momentum distribution are observed between the two values for $M_L$. We use our theoretical results to model how the spin-orbit interaction affects electron emission along the laser polarization axis. Under the assumption that an initial C atom is prepared at zero time delay with $M_L=0$, the dynamics with respect to time delay of an ionizing probe pulse modeled by using RMT theory is found to be in good agreement with available experimental data.

• Received 16 May 2014

DOI:https://doi.org/10.1103/PhysRevA.90.033402