Dicke-narrowed spectral line shapes of CO in Ar: Experimental results and a revised interpretation

Collisional line shifting and broadening in the fundamental P-branch of CO in Ar between 214 and 324K

“…Fig. 2 of [17] further shows that the fitted values exhibit the correct linear behaviour with pressure in the P0.2 atm regime. In this paper, we restrict our consideration of the broadening to that regime.…”

“…We fitted m as part of our investigation of Dicke narrowing, the results of which are reported in [17]. However, above 0.2 atm, the line shape is insensitive to m, so that the fitting of m has no significant effect on the fitted values of C 0 reported here.…”

“…However, C 0 is not necessarily the half width at half maximum of the line even in the hydrodynamic limit: when speed dependence is significant, speed-changing collisions (accounted for by S f VC ) also influence the shape and width of the line. This point is discussed further in [17] and references therein.…”

“…Our method includes speed-dependent collisional broadening, Doppler broadening, and Dicke narrowing. The latter effect (and the approach in general) is considered in detail in the preceding paper [17]. In the current paper, we are concerned primarily with the broadening and shifting.…”

“…In the current paper, we are concerned primarily with the broadening and shifting. The results presented here are derived from the same set of measurements as used in [17], and we refer the reader to that paper for the experimental details. However, for the readerÕs convenience, we do repeat here selected points related to the calculation of the line shape, focussing on the determination of the collisional broadening.…”