  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$^{14}$ W 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 modelled
using RMT theory is found to be in good agreement with available experimental
data.
