HR: 1330h
AN: SA43A-02 [Abstracts]
TI: The O(1S - 1D,3P) Line Intensity Ratio
AU: * Slanger, T G
EM: tom.slanger@sri.com
AF: SRI International,
Molecular Physics Laboratory, 333 Ravenswood Ave., Menlo Park, CA 94025 United States
AU: Sharpee, B D
EM: brian.sharpee@sri.com
AF: SRI International,
Molecular Physics Laboratory, 333 Ravenswood Ave., Menlo Park, CA 94025 United States
AU: Cosby, P C
EM: philip.cosby@sri.com
AF: SRI International,
Molecular Physics Laboratory, 333 Ravenswood Ave., Menlo Park, CA 94025 United States
AU: Minschwaner, K R
EM: krm@kestrel.nmt.edu
AF: New Mexico Inst. Mining & Tech., Physics Dept., Socorro, NM 87801 United States
AU: Siskind, D E
EM: siskind@uap2.nrl.navy.mil
AF: Naval Research Laboratory,
Code 7641, 4555 Overlook Ave. SW, Washington, DC, 20375 United States
AB:
The line intensity ratio of the two optically-forbidden atmospheric emissions, O(1S-1D) at 557.7 nm and O(1S-3P)
at 297.2 nm, must be a single-valued number in the upper atmosphere because the upper level is common to both lines. The
calculated transition probability ratio A(557.7)/A(297.2) is 16, by several authors, and the ratio found in the laboratory is significantly larger. Field observations require space-based instruments, in which case calibration between the two
wavelengths is the critical issue. We circumvent this problem by using the O2 Herzberg I emission system as a bridge
between the UV region below 310 nm and the ground-accessible region above that wavelength. These two spectral regions can be separately calibrated in terms of intensity, and the results of a disparate set of observations (satellite, rocket,
ground-based) lead to A(557.7)/A(297.2) ratios that are consistently much smaller than the calculated value. These results
have consequences for auroral and dayglow processes, and it is particularly important to ascertain the cause of the
substantial difference between theory and observation.
DE: 0310 Airglow and aurora
DE: 0317 Chemical kinetic and photochemical properties
DE: 2407 Auroral ionosphere (2704)
DE: 3359 Radiative processes
SC: SPA-Aeronomy [SA]
MN: 2005 Joint Assembly