MEASUREMENTS OF THE EARTH'S STRATOSPHERE USING BALLOON-BORNE FAR INFRARED SPECTROSCOPY: SIMULTANEOUS MEASUREMENTS OF $HO_{X}, NO_{X}$, AND $CL_{X}$

Author Institution: Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138.The Smithsonian Astrophysical Observatory far-infrared spectrometer (FIRS-2) measures vertical mixing ratio profiles in the stratosphere from a ballon platform. The FIRS-2 is a high-resolution $(0.004 cm^{-1} unapodized)$ two-beam Fourier transform spectrometer which measures thermal emission in the regions $80-210 cm^{-1}$ and $350-700 cm^{-1}$. Observations are made at various elevation angles, with absolute pointing referenced to a gyroscope and accelerometer-stabilized single-axis platform. Molecules currently measured include $OH, HO_{2}, H_{2}O, H_{2}O_{2}, O^{3}P, O_{2}, O_{3}, HCl, HF, HBr, HOCl, HOBr, CO, CO_{2}, N_{2}O, NO_{2}, HNO_{3}, and HCN$. The measurements, the development of the relevant spectroscopy, and the application of the measurments to improving models of the photochemistry of the ozone layer are discussed