Doubly differential cross sections of secondary electrons ejected from gases by electron impact: 50-400 eV onN2

Doubly differential cross sections of secondary electrons ejected from ${\mathrm{N}}_2$ by electron impact have been measured by a crossed-beam method. The incident energies used were 50, 70, 100, 200, and 400 eV. The energy and angular range of secondary electrons measured were from 1.0 eV to one-half of the difference between the incident energy and ionization potential and 12° to 156°, respectively. The present results have been compared with two previous measurements and considerable discrepancies were found.