The populations of some excited states of singly ionized argon in an argon laser discharge

Abstract

The population densities of the 3d ⁴F_{5/2, 7/2, 9/2}, 3d ⁴D_{5/2, 7/2} and 4s ⁴P_{1/2, 3/2, 5/2} levels of ionized argon in an argon ion laser discharge have been measured by a line absorption technique. The populations of these levels show a linear increase with discharge current. An estimate of the pumping rate of the upper laser configuration (4p) by electron collision with these 3d and 4s levels indicates that this may be an important, perhaps a dominant process in populating the 4p configuration.