Absolute measurements of absorption at the iodine-laser frequency in atmospheric gases.
The absorption cross sections at the chemical-iodine-laser frequency for methane and carbon dioxide in an atmosphere of dry air were determined with a photoacoustic cell to be (8 +/- 2) x 10(-24) and (5.4 +/- 0.4) x 10(-25) cm(2), respectively. A multipass absorption cell and a Fourier-transform spectrometer were used to obtain a cyclopropane absorption cross section of (3.47 +/- 0.02) x 10(-24) cm(2) at 14 076 cm(-1) for the photoacoustic-cell calibration.
Bragg
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McDonnell Douglas Research Laboratories, PO Box. 516, St. Louis, Missouri 63166, USA.
Lawton
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Wiswall
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