Excitation of Nitrogen Gas by Fission Fragments along the Entire Track

Abstract

Luminescence produced in nitrogen in small segments of the tracks of fission fragments was studied with a pulse technique. The amount of formation of the C3πu state of nitrogen per unit distance, L*, was measured over the entire path length of the low-mass fragment group as a function of track length. The energy loss per unit distance dE/dr can be approximated by L* over the entire fission fragment path length. The observance of light produced from the second positive group (C3πu→B3πg) near the end of the track, despite a major change in the primary mode of energy deposition by the fission fragments, indicates that a more detailed theory of chemical production from the deposition of energy by a heavy charged particle needs to be formulated in the regime of nuclear elastic collisions which exists at the end of the particle's range.