Francis X. Kneizys

Coriolis Interaction in the ν1 and ν3 Fundamentals of Ozone

The v1 and v3 vibration rotation spectrum of 16O3 in the 9.0‐μ region has been analyzed. The two vibrational states are coupled through a Coriolis term, iY13Py, and a second‐order distortion term, −X13(PxPz+PzPx), in the Hamiltonian. The interaction has been treated by numerically diagonalizing the secular determinant for the two states with the coupling included. The effect of the interaction on the intensities has been considered and absorption contours calculated in satisfactory agreement with experiment. With the distortion parameters fixed to the ground‐state values the following constants have been obtained: ν1=1103.157, A1=3.5569, B1=0.44272, C1*=0.39262, ν3=1042.096, A3=3.5004, B3=0.44125, C3*=0.39097, Y13=−0.466, and X13=−0.0098 cm−1. The value of the dipole‐moment ratio, (∂Mz∂Q3|0Q3)⧸(∂Mx∂Q1|0Q1), is 10.0±1.5.

Convolution algorithm for the Lorentz function

An algorithm for the accelerated convolution of the Lorentz function with spectral line data has been developed. The method involves the decomposition of the Lorentz function into subfunctions spanning finite domains. The subfunctions are convolved independently with line data at appropriate sampling intervals. The spectral absorption is obtained by superposition of the independent convolutions. A criterion for the specification of the sampling interval is described.

Validated band model for the NO fundamental

A previously reported transmission model for the 5.3-microm band of NO, whose defining parameters had been developed with line-by-line calculated spectra, is now presented in validated and upgraded form through the use of measured transmittance data. The model consists of a double-exponential function, which approximates homogeneous-path transmittance at 5-cm(-1) intervals with a sepctral resolution of 20 cm(-1). The use of the proposed model parameters in transmittance calculations yielded an average standard deviation of 0.28% and an overall maximum deviation of 1.48% from the measured transmittance data. This compares favorably with the results obtained with the use of the previous parameters to predict the measurements, which resulted in an average deviation of 1.05% and overall maximum transmittance deviation of 4.94%.

Complex susceptibility for collisional broadening

A unified approximate expression for the real part of the susceptibility for collisionally broadened transitions, including line coupling, has been developed. The Hilbert transform has been applied to the impact approximation line shape (Kramers-Kronig relationship) to obtain a result that is applicable from the microwave to the infrared. The approximate function has been compared numerically with the exact result using a newly developed algorithm. The results are applicable to spectral computations of the index of refraction and propagation delays.

Effects of Atmospheric Obscurants on the Propagation of Optical/IR Radiation

Every optical remote sensor, whether looking at the natural atmospheric constituents or other obscurants or pollutants, has to be able to look through the atmosphere. It is therefore important that one understands and can reliably predict the propagation properties of the ambient atmosphere for these remote sensing systems.