Modeling of the processes of ionization and excitation of nitrogen molecules by short and intense laser pulses

We present a model describing ionization and excitation of nitrogen molecules by a strong and short laser pulse. Different from previous publications, both processes are considered within the same formalism of the density matrix. We account for the dependence of the dipole moment on the vibrational quantum number and for a large number of excited levels. Populations of the excited levels depend significantly on the laser intensity, wavelength, polarization, and pulse duration.