Simultaneous excitation and ionization of Ar by electron impact

Absolute cross sections for the simultaneous excitation and ionization of Ar by electron impact have been measured by the optical method. In particular we report the measurements of eighteen levels belonging to the 3 p 4 4 p and 3 p 4 4 d configurations of Ar II. The dependence on electron energy of the excitation functions of some 3 p 4 4 p levels was studied in the range 0-6000 eV.