Atomic data are needed for the quantitative interpretation of experimental spectroscopic data in laser ablation devices. They include cross sections and rate coefficients for various processes such as ionization, excitation, recombination, charge exchange, and also transition probabilities for line emission. This work presents results on electron impact excitation and ionization per photon coefficients as related to the interpretation of plume emissions accompanying 248 nm laser ablation of graphite in vacuum. We used the Atomic Data and Analysis Structure (ADAS) computer package and the generalized collisional-radiative model to simulate experimental line brightness and emissivities from plasma.