Fourier transform spectroscopy and cross section measurements of the Herzberg III bands of O-2 at 295 K

Fourier transform spectroscopic measurements of the absorption bands of the Herzberg III (A' (3)Delta(u)-X (3)Sigma(g)(-)) of O-2 at 295 K have been m ade with a resolution of 0.06 cm(-1) in the wavelength region 240 to 275 nm . Rotational line positions are determined with an accuracy of 0.005 cm(-1) , and rotational term values are presented for the vibrational levels, v'=4 -11. Precise band oscillator strengths of the (4,0)-(11,0) bands are obtain ed for the first time by direct measurement by summing the cross sections o f individual rotational lines of the bands. The rotational line strengths a nd the branching ratios are also presented for the same bands. The continui ty relationship for the band oscillator strengths to photodissociation cont inuum cross sections has been applied to the three-band systems. (C) 2000 A merican Institute of Physics. [S0021-9606(00)01221-6].