6533b856fe1ef96bd12b2554

RESEARCH PRODUCT

High Resolution Coherent Anti-Stokes Raman Spectroscopy (CARS) Of O 2 And CO 2

subject

description

With the help of high spectral quality (linewidth , 6 MHz) injection-locked flashlamp-pumped dye lasers, high resolution Coherent Anti-Stokes Raman Spectroscopy (CARS) has been applied to the study of the Q-branches of 0 2 and CO 2 . The Q-branch linewidths of 02 were obtained from the first nine transitions (J 2 = 1 to 17) recorded at pressures from 0.094 to 1 atm at room temperature. A least squares program was employed to fit calculated spectra to experimental spectra by adjusting different parameters. The collisional broadening coefficients we have obtained are consistent with available Raman data. We have also studied the Q-branch of the fundamental v1 band of CO 2 in the Fermi resonance region near 1285.5 cm -1 . The spectrum was recorded at a pressure of 5 kPa (37.5Torr) at room temperature and it was possible to resolve this band for the first time. We measured the line positions and collisional widths for the transitions with J values from 8 to 38. Our experimental line positions are in excellent agreement with those derived from molecular constants given in the literature. The observed linewidths agree for most of the lines within 5 % with the values calculated from a recently developed model.