Knowledge Bank

For $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}O3$, accurate $H2$-broadened halfwidths are difficult to obtain for a large number of transitions. Recent $measurements1$ have allowed assigning average air-broadened halfwidths of ozone for A-type bands, $\alpha$ = $0.083cm-1$/atm, and for B-type bands, $\alpha$ = $0.077cm-1$/atm at 296K. These measurements, however, were not extensive enough to give J-dependence of the halfwidths. Theoretical $N2$-broadened halfwidths have been determined for a number of $\nu 3$ (A-type) and $\nu L$ (B-type) transitions of ozone. The halfwidths have been evaluated using the Anderson-Tsao-Ournutte theory of collisional-broadening and by the more rigorous Quantum Fourier Transform theory due to $Davies.2$ In the calculations, contributions to the halfwidth from dipole-quadrupole interaction and quadrupole-quadrupole interaction are considered. Both methods are compared with experiment. From the study, air-broadened halfwidths will be calculated for an extensive list of transitions for ozone, and these will appear on a future AFGL Main Gas Compilation. 1. J. M. Hoell, C. N. Harward, C. H. Bair, and B. S. Williams, opt. Eng. 21, 548(1982); J. S. Margolis, Appl. Opt. 21, 3109 (1982). 2. R. W. Davies, Phys. Rev. A12, 927 (1975). This work was supported by the Air Force Office of Scientific Research, through AFGL task 2310G1.