Quantitative measurements of O-2 b <- X(2,1,0 <- 0) bands by using cavity ring-down spectroscopy

Quantitative measurements of individual rotational line intensities of mole cular oxygen are made for the (0 <-- 0), (1 <-- 0), (2 <-- 0) bands of the b(1)Sigma(g)(+) <-- X(3)Sigma(g)(-) transition using highly sensitive cavit y ring-down spectroscopy (CRDS). The absorption profiles of six rotational lines of the three bands of O-2 are measured under pressures up to 1 atm. C orrections have been made to eliminate the effect of laser bandwidth on the absorption intensity measurements. The gas detection limits in our measure ment for the three bands are 0.04, 0.80 and 7.00 Torr, respectively. The li ne strengths in the three bands of O-2 have been determined by CRDS and are in good agreement with previous results using a multiple pass absorption c ell. (C) 1999 Elsevier Science B.V. All rights reserved.