Measurements on the index of refraction of air for wave lengths from 2218 A to 9000 A

Abstract

Astronomical observations 2 . Prism method 3. Interferometer methods 4. Diffraction grating method 5. Summary of previous work II. Purpose 1. Wave length corrections for temperature and pressure of air 2. Wave length corrections to vacuum III. Experimental method 1. Fabry and Perot interferometer for measurement of n IV. Description of apparatus 1 . General plan 2. Sources 3 . Interferometers 4. Air chamber 5. Pressure gages 6. Constitution of the air 7. Photographic V. Experimental procedure 1. Optical adjustments 2. Temperature regulations 3. Pressure observations 4. Photographic exposures 5. Measurement of ring diameters VI. Reduction of observations 718 1 . Correction to 760 mm 7 2 . Final values of n -1 3. Cauchy dispersion formula 4. Sources of error VII. Applications 724 1. Correction of wave-length measurements made in air at other than normal temperatures and pressures 2 . Corrections for water vapor in the air 3. Corrections to convert to vacuum values 4. Astronomical refraction 5. Optical temperature coefficient 6. Dispersion formulas VIII.