Abstract
There is described a simple photoelectric spectrophotometer, developed to determine the precipitable water in a vertical column of the atmosphere. A transmission replica grating is used as the dispersing element and an infra-red-sensitive photo-tube as the energy receiver. The photo-tube current is amplified by a negative feed-back d.c. amplifier and is read either by means of a 500 microampere ammeter or recorded by a high speed potentiometer recorder. Measurements are obtained by comparing the radiant flux in the 0.94μ water vapor absorption band with that at 1.01μ where no absorption occurs. A single-mirror heliostat is utilized to keep the spectrophotometer focused on the sun. An approximate calibration was obtained by plotting the spectrophotometer ratios against the total precipitable water values in a vertical column of the atmosphere as calculated from radiosonde moisture data.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
