Solar Radiation and Atmospheric Attenuation at 6-Millimeter Wavelength
- 1 March 1957
- journal article
- conference paper
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 28 (3) , 295-298
- https://doi.org/10.1063/1.1722733
Abstract
A microwave radiometer of the Dicke type for the 6‐mm wavelength range has been built and operated to measure radiation from the sun and attenuation in the earth's atmosphere. The total vertical attenuation in the earth's atmosphere on four clear summer days averages 1.2 db. It is presumably due principally to oxygen, since the 6‐mm wavelength is well up on one wing of the 5‐mm absorption line. The quoted values are in agreement with a line‐width constant of 0.02 cm−1. Attenuation in clouds is highly variable. An additional 1 db above the fair‐weather value is typical for a thin overcast. Measurements during the summer of 1956 indicate an effective solar temperature of about 4500°K. This value is appreciably lower than temperatures reported at 7.5 and 8.5 mm, and it favors a model of the lower chromosphere which assumes temperatures well below the optical surface value of 5700°K.This publication has 6 references indexed in Scilit:
- A Dicke-type radiometer for the 7-8 MM wavelength range.The Astronomical Journal, 1956
- Observations of Solar and Lunar Radiation at 15 MillimetersJournal of the Optical Society of America, 1955
- Temperature Gradient in the Sun's Atmosphere Measured at Radio Frequencies.The Astrophysical Journal, 1951
- The Absorption of Microwaves by OxygenPhysical Review B, 1947
- Atmospheric Absorption Measurements with a Microwave RadiometerPhysical Review B, 1946
- The Measurement of Thermal Radiation at Microwave FrequenciesReview of Scientific Instruments, 1946