Temperature Dependences of the Quantum-Mechanical and Semi-Classical Spectral-Line Widths and the Separation n0 of the Impact and Non-Impact Regions for an Ar-PerturbedK-Radiator System

Abstract EN

Quantum-mechanical and semi-classical spectral-line shapes are computed at T=400, 800, and 1000 K for the line core of the 5802 Å line of the Ar-Perturbed/K-Radiator system.

HWHMs (w's) are measured from computed full spectral-line shapes.

The final-state pseudopotential is for the 7s2S1/2 state, and the initial-state potential is for the 4p2P3/2,3/2 state.

Three high-pressure (P) log(w)—versus—log(P) curves, corresponding to the non-impact region, intersect a similar set of low-P, impact-region curves at intersections, P0's.

Similarly, for two sets of log(w)—versus—log(n) curves, which yield intersections, n0's, where n is the perturber density.

These n0's and p0's separate the two regions and represent the upper limits of the impact regions.

A specific validity condition for the impact region is given by the equation n≤n0.

From an earlier spectroscopic, Fabry-Perot paper, wexpt=0.021 cm−1 at T=400 K and P=10 torr.

Two theoretical values, wtheor=0.025 and 0.062 cm−1 corresponding to two different pseudo-potentials, are reported.

Two T-dependent figures are given, in which the first shows an increase in the impact region with T, based on P as the basic parameter, and the second which shows a decrease in the impact region with T, based on n as the basic parameter.