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The Refractivity of Air
1National Bureau of Standards, Washington, DC 20234.
Abstract:
The air density equation of Jones, Edlén's dispersion formula for standard air, and Edlén's empirically-derived expressions for the effects of Co2 abundance and water vapor partial pressure on refractivity have been combined into a simplified equation for the refractivity of air, and estimates have been made of uncertainties in calculated refractivity. Under ambient conditions typical of metrology laboratories, the agreement between the simplified equation and Edlén's formulation is well within the uncertainty in each. The simplified equation is valid in the visible region.
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