TEMPERATURE DEPENDENCE OF $N_{2}$-BROADENED HALFWIDTHS OF OZONE

$^{1}$R. R. Gamache and R. W. Davies, J. Mol. Spec. $109$, 283--299 (1985). $^{2}$J. M. Colmont and N. Monnanteuil, J. Mol. Spec. $104$, 122--128 (1984). $^{3}$B. J. Connor and H. E. Radford, Center for Astrophysics, Smithsonian Astrophysical Observatory, Cambridge, MA, private communications. $^{4}$G. D. T. Tejwani and E. S. Yeung, J. Chem. Phys. $63$, 1513--1517 (1975). $^{5}$J.-Y. Mandin, J.-M. Flaud and C. Camy-Peyret, Laboratoire de Physique Mol\'eculaire d'Optique Atmosph\'erique, CNRS, Orsay, France, private communications. This work was supported by the Air Force Office of Scientific Research through AFGI Task 2310G1.Author Institution: University of Lowell Center for Atmospheric Research; Air Force Geophysics Laboratory, Optical Physics DivisionWe have calculated nitrogen-broadened halfwidths of ozone over a temperature range from 200 to 350 K. The calculations were done using the QFT-ID $method^{1}$ which has been shown to give halfwidths to better than 10%. The temperature dependence of the broadening coefficient has been evaluated for a wide range of transitions that cover J from 1 to 35, the full manifold of Ka for particular J values and for some transitions of stratospheric importance. The temperature dependence is given in terms of the temperature exponent, n, from the expression $\gamma(T)/\gamma(T_{0}) = (T_{0}/T)^{n}$, for the 126 transitions studied. The results indicate an average temperature exponent of n = 0.77 for $N_{2}$-broadening of ozone. The results are not strongly dependent on the rotational quantum number J but do show some dependence on Ka. Comparison is made with experimentally determined temperature $coefficients^{2,3}$ and other theoretical $calculations.^{4,5}