Measurements of collisional broadening and the shift of argon spectral lines using a tunable diode laser

Abstract

Absorption line profiles of neutral argon spectral lines have been investigated using a GaAlAs diode laser as a light source. The broadening and the shift coefficients for the 811.5 nm line, which terminates on the lowest metastable state 1s₅, have the values (1.42+or-0.14)*10^-20 and (4.4+or-0.4)*10^-21 cm^-1 cm³, respectively. From the broadening coefficients for the 810.4 and 840.8 nm lines, which terminate on the resonance states 1s₄ and 1s₂, the oscillator strengths for the resonance transitions at 106.7 and 104.8 nm have been determined to be (49+or-5)*10^-3 and (207+or-20)*10^-3, respectively. The shift coefficient for the 810.4 nm line was about a half of the value for the 811.5 nm line and no shift was observed for the 840.8 nm line in accordance with the theory of Lewis (1967).