Extreme-Wing Line Broadening and Cs-Inert-Gas Potentials

The emission profiles of the cesium resonance lines broadened by collisions with inert gases have been measured from about 50-1000 cm^-1 from line center. The emission is observed from optically excited Cs in a cell whose temperature is varied from about 300-800^. By measuring the wing intensity relative to the entire line intensity from optically thin Cs, the profiles can be related to theoretical models without knowledge of the cesium density. The quasistatic theory of line broadening, extended to include the distribution of perturber positions about the Cs*, is used to analyze the data. The observed temperature dependence of the emission profiles is associated with the temperature dependence of the perturber distribution in the Cs*-inert-gas adiabatic potential. The quasistatic spectrum depends on the difference between excited- and ground-state adiabatic potentials, so each potential is thereby separately determined from the data. The X, A, and B potentials for the 3. 5-5- region are given.