O3ABSTR84.INF 4/1/93 HIGH RESOLUTION ABSORPTION CROSS SECTION MEASUREMENTS OF OZONE AT 195 K IN THE WAVELENGTH REGION 240-350 nm Planetary Space Science, 32(2): 239-248, 1984 D.E. FREEMAN, K. YOSHINO, J.R. ESMOND AND W.H. PARKINSON Harvard-Smithsonian Center for Astrophysics Cambridge, MA, U.S.A., 02138 ABSTRACT Cross sections of the Hartley-Huggins bands of O3 at the temperature 195 K have been obtained from photoabsorption measurements at column densities in the range 2 x 10^17 - 1 x 10^21 cm-2 throughout the wavelength region 240-350 nm with a 6.65 m photoelectric scanning spectrometer equipped with a 2400 lines mm-1 grating and operated at an instrumental width (FWHM) of 0.003 nm. The assumptions made in putting measured relative cross sections on an absolute basis are discussed. Fine structure in the cross section observed in the Huggins bands is illustrated in the region 323-327 nm where shallow features of width 0.01-0.02 nm occur superposed on a stronger apparent continuum exhibiting broader wavy structure. --------------------------------------------------------------- The cross sections were later put on a different absolute basis reflecting the absolute cross section measurements at dicrete points of ozone at three different temperatures, published in 1988 (Planetary Space Science, 36(4): 395-398). The files available here reflect this recalibration. ABSOLUTE ABSORPTION CROSS-SECTION MEASUREMENTS OF OZONE IN THE WAVELENGTH REGION 238-335 nm AND THE TEMPERATURE DEPENDENCE K. YOSHINO, D.E. FREEMAN, J.R. ESMOND AND W.H. PARKINSON Harvard-Smithsonian Center for Astrophysics Cambridge, MA 02138, U.S.A. ABSTRACT Laboratory measurements of the absolute absorption cross- section of ozone at the temperatures 195, 228 and 295 K have been made at several discrete wavelengths in the region 238-335 nm. Our results for ozone at 295 K are in excellent agreement with those of Hearn (1961, Proc. phys. Soc. Lond., 78, 932), who used a different technique. Our absolute cross- section measurements of ozone at 195 K have been used to put our recent relative cross-section measurements at that temperature (Freeman et al., 1984, Planet. Space Sci., 32, 239) on a firm absolute basis throughout the region 240-335 nm; these recalibratied cross-sections are available as numerical compilations on magnetic tape from the National Space Science Data Center, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A.