Cross sections for the production of positive ions by electron impact on F2

First measurements on the ionization cross sections for the production of F2+ and (F+ + F22+) ions from F2 by electron impact are reported for an electron impact energy range of threshold energies to 1 keV and for F2+ at 100eV. These measurements were carried out in a crossed-beam apparatus using the pulsed technique and the partial pressure method to determine the absolute cross sections. Total ionization cross sections at each electron impact energy were obtained by numerical summation of the respective partial ionization cross sections. (Author)